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The aim of the research was to improve detection accuracy of the blood spots and meat spots in eggs, which can provide consumers with high-quality eggs. Spectroscopy technology and multiple classifier fusion for abnormal egg detection were investigated. Micro fiber spectrometer (Ocean Optics company, USB2000+) was used to collect the transmittance spectroscopy of both normal and abnormal eggs, which were from Hubei Shendan Healthy Food Co., Ltd. After outliers detection and elimination, there were 336 eggs in all, which were randomly assigned to training set and test set; among the 336 eggs, 224 (about two-thirds of the total) were assigned to the training set, and the remaining 112 (about one-third of the total) were assigned to the test set. Before multiple classifier fusion, all data collected from micro fiber spectrometer was preprocessed including the methods of SNV (standard normal variate), smoothing and MSC (multiplicative scatter correction). usion of multiple classifiers was used to detect the foreign bodies of eggs on the basis of single-classifier. Firstly, five single-classifiers which was inclusive of Naive Bayes classifier, Mahalanobis distance classifier, PLS-DA (partial least squares-discriminate analysis) classifier, AdaBoost (adaptive boosting) classifier and SVM (support vector machine) classifier were all trained, and five groups of classification results were attained. In order to choose suitable one from these five single-classifiers, according to diversity measure, output disagreement measure and error agreement measure were introduced and used, and Naive Bayes, AdaBoost and SVM classifiers were selected as the single-classifiers; then, on the basis of these three selected single-classifiers, through feature level fusion, 21 base-classifiers were obtained. In order to get the final base-classifiers which were used to accomplish the multiple classifier fusion, in a similar way, through output disagreement measure and error agreement measure again, 5 base-classifiers were chosen from these 21 base-classifiers. Finally, 5 basic-classifiers were fused by weight vote strategy on the decision level. The weight vote strategy was that each base-classifier was allocated a weight value according to its accuracy rate, and the higher accuracy rate a base-classifier had, the larger weight value it would be allocated, because it was more trusted. Detection accuracy rate of ensemble classifier, which was formed after multiple classifier fusion, was 92.86% and 91.07%, respectively for normal eggs and abnormal eggs. As a contrast, among all the single-classifiers and base-classifiers, the highest detection accuracy of normal eggs in the test set was 91.07%, which came from AdaBoost (500-600 nm), and the highest detection accuracy of abnormal eggs in the test set was 89.29%, which came from SVM (550-600 nm). The experiment results showed that the model established by multiple classifier fusion could take full advantage of the information which came from each single-classifier or base-classifier, and in the aspect of the detection accuracy of either normal eggs or abnormal eggs, the model established by multiple classifier fusion was indeed superior to the model established by each single-classifier or base-classifier. Even though the detection accuracy was enhanced by a small margin, considering that a large number of either normal eggs or abnormal eggs were being produced and being detected in lots of companies that were involved in eggs, in this meaning, the slight promotion of detection accuracy was of great significance. [ABSTRACT FROM AUTHOR]

Breathing is an important physiological activity of egg as a living organism, and it has a great influence on its storage, conveyance and incubation. Therefore, it is of great significance to study egg's breathing regularity and respiration intensity in a day and during its storage time in a month. In this paper, non-invasive micro-test technique (NMT) was used to real-time monitor O2 flux passing in and out the eggs through the eggshell and study the breathing regularity and the respiration intensity of the eggs. With this method, gas exchange (O2) was measured and it was confirmed that breathing indeed exists. In order to study egg's respiration in a day, a customized micro-testing examination platform was constructed for the real-time monitoring of the intensity and rate of oxygen exchange between an egg and its external environment at 4 time points (6:00, 12:00, 18:00, and 24:00). On the other hand, egg's O2 flux was measured at the same time in a day during a month as to seeking for breathing regularity in its storage time. It was indicated that the optimal distance of probe towards the egg surface was 50 μm and the blunt end of the egg was selected as the optimum measurement location via the pre-experiment. The results show that there are three breathing patterns of eggs, consuming O2, exhaust O2, and both including consuming and exhausting O2. After group A testing, it is concluded that both fertilized and non-fertilized eggs breathe strong at dawn and weak at noon regularly in a day and the respiration intensity of the two types of eggs perform difference at different time points. Fertilized eggs have more active physical activity and the process of metabolism than those of non-fertilized ones. Fertilized egg respiration shows significant difference (P<0.05) at noon and dawn in a day, but non-fertilized egg does not. In addition, after group B testing, it is intended that during storage time in a month, there exists two breathing peaks in its storage period in a month, and each peak appears at the eggs quality changing time. The second peak value exceeds the first peak value. It reveals that there's a unique breathing pattern of eggs that O2 respiration rate is high when life metabolism is active, and low when life metabolism is negative. Eggs laid lately are breathing relatively positive. This study can provide a reference for optimizing storage conditions, improving the hatchability of fertilized eggs and hatching egg embryo in further research. [ABSTRACT FROM AUTHOR]

This study aims to enhance the color and microbiological qualities of a raw beef using natural ingredients. Nitroso-hemoglobin (NO-Hb) integrated with vitamin C (VC), calcium lactate, and ginger complexation were used as natural inhibitors against the growth of aerobic and pathogenic bacteria, namely (Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Salmonella. NO-Hb inhibited E. coli , S. aureus , and Salmonella , and enhanced the color stability more than nitrite in the minced beef model. After the multiexponential analysis of relaxation decays, the water component (T 2b) was analyzed using the low-field NMR. The results indicated that, at the 7th d of cold-storage the third component (T 2) was detected. Significant correlations were observed between T 21 and T 22 relaxation times and water-holding capacity in minced beef, implying that the LF-NMR measurements could be an efficient method for the determination and prediction of beef freshness. NO-Hb- ginger mixture, as a novel ingredient, could be used instead of nitrite in terms of meat safety. • NO-Hb, from fresh beef blood and use as a nitrate substitute • NO-Hb, VC, Ca, and ginger addition improve color and inhibit of bacteria. • NO-Hb, used as a novel ingredient used in term of safely • LF-NMR has been clearly established the changes in T2 of water. [ABSTRACT FROM AUTHOR]

Preserved eggs are a type of egg products made from duck eggs and have anti-inflammatory activity. The purpose of this study was to investigate the effects of preserved egg simulated gastrointestinal digests on the apoptosis of HT29 and HepG2 cells. The cells morphology, apoptosis and apoptosis associated genes (Bcl-2, Bax, COX-2) and proteins (caspase-3 and caspase-9) were evaluated. The results showed that preserved egg digests significantly up regulated the expression of genes Bax, caspase-3 and caspase-9, which are involved in cell apoptosis, and up regulated the expression of the pro-apoptotic factors Bcl-2 and COX-2 both in HT29 and HepG2 cells, leading to a reduction in the ratio of Bcl-2:Bax proteins. The results also showed that the apoptosis of HT29 and HepG2 cells was promoted by the PED in a dose-dependent manner. Thus, PED may serve as a potential functional food for cancer treatment. • The anticancer activity of preserved eggs was explored. • Preserved eggs digests promoted HT29 and HepG2 cells apoptosis in a dose dependent manner. • Preserved eggs significantly up regulated the expression of genes Bax, caspase-3 and caspase-9. [ABSTRACT FROM AUTHOR]

As two major proteins of egg white, the interaction between lysozyme (LYZ) and ovalbumin (OVA) has been studied. In the present research, the mechanism and kinetics of the interaction between LYZ and OVA were studied using several methods, including cyclic voltammetry (CV), dual polarization interferometry (DPI) and surface plasmon resonance (SPR), and the effect of their interaction on the activity of LYZ was investigated using a bacteriolytic activity assay. Cyclic voltammograms showed that there was an interaction between these two proteins. DPI results indicated that the interaction is a type of chimeric mode, and the K A and K D of the interaction were 498 and 2.01 × 10−3 mol/L, respectively, calculated from the fitting of the surface plasmon resonance curve. The bacteriolytic activity assay showed that the interaction between these two proteins reduced the bacteriolytic activity of LYZ. [ABSTRACT FROM AUTHOR]

This study investigated the impact of ultrasound pretreatment and phenolic binding on the structure characteristic and foaming properties of egg white (EW). EW treated without ultrasound (NEW) and with ultrasound (UEW) (power for 28% and time for 25 min: on-time 3 s and off-time 2 s) were incubated separately at 25 °C for 2 h with gallic acid (GA) and epigallocatechin gallate (EGCG) at pH 7.0. Phenolic treatment caused a significant loss of sulfhydryl content, with a more remarkable effect observed in UEW, especially at 120 μmol/g concentration. Both phenolics significantly decreased the surface hydrophobicity and slightly increased the disordered secondary structure of protein. Additionally, the microenvironment polarity of protein molecules was increased by phenolic treatment corroborated by UV absorption blue shift, especially for 240 μmol/g GA-UEW. After ultrasound pretreatment, low EGCG concentration (20 μmol/g) significantly increased the foaming ability. The 240 μmol/g EGCG treatment notably increased the reduced foaming stability by ultrasound from 81.00 to 95.10% (p < 0.05), which was due to high absolute ξ-potential value. This study has shed light on the mechanisms underlying the influence of unfolding structure by ultrasound treatment on phenolic binding. Image 1 • Phenolic treatment especially EGCG significantly decreased sulfhydryl content. • Protein surface hydrophobicity was obviously decreased by phenolic treatment. • EGCG treatment increased the foaming stability of egg white. • EGCG was stronger than GA in binding affinity with egg white. • Ultrasound pretreatment contributed to the binding of phenolic to protein. [ABSTRACT FROM AUTHOR]

Obesity induced by consuming a high-fat diet (HFD) is a major risk for nonalcoholic fatty liver disease, which has become a worldwide health problem. To study the effects of high-density lipoproteins of egg yolk (EYHDL) on mice with HFD induced obesity, lipidomic analyses using ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) was done with serum and liver samples on 60 and 100 days. The results showed that EYHDL significantly alleviated mouse obesity by decreasing adipose tissue accumulation, serum low-density lipoproteins cholesterol, total cholesterol, hepatic triglycerides and development of hepatic steatosis. The EYHDL group was separated from HFD on the orthogonal partial least squares-discriminant analysis score plots, suggesting the beneficial effect of EYHDL on dyslipidemia in obese mice. Volcano plots combined with S-plots showed that the potential biomarkers contributing to these differences were diglycerides, phosphatidylcholines, phosphatidylinositols and lysophosphatidylcholines. On the basis of these biomarkers, glycerophospholipid metabolism is probably the main pathway regulated by EYHDL in obese mice. In summary, EYHDL alleviated hyperlipidemia in obese mice by regulating the phosphatidylcholines and neutral glycerolipids composition, and the lipid biomarkers can be used to better assess the mechanism and therapy for HFD-induced obesity. Image 1 [ABSTRACT FROM AUTHOR]

• Phosphorylation improved the calcium chelating ability of collagen peptide. • Both PCP and PCP-Ca could promote MC3T3-E1 cell the mRNA level of ALP, Runx2, OCN, OPN and Col 1. • PCP-Ca had significant effect on mineralization of MC3T3-E1 cellt. In this study, porcine bone collagen peptide (CP) was phosphorylated with sodium tripoly phosphate (STP) in order to improve its calcium binding capacity and osteogenic activity. Firstly, the phosphorylation process were optimized by an orthogonal experiment. Then, the effects of CP, phosphorylated CP (PCP), CP-calcium chelate (CP-Ca) and PCP-Ca on proliferation, differentiation and mineralization of MC3T3-E1 cells were investigated. The results showed that all of the CP, PCP, CP-Ca and PCP-Ca could enhance the proliferation, differentiation and mineralization of MC3T3-E1 cells by increasing the mRNA expression levels of alkaline phosphatase (ALP), Runt-related transcription factor-2 (Runx2), osteocalcin (OCN), osteopontin (OPN) and collagen type I (Col I), as well as the protein expression levels of Runx2 and β-Catenin. Especially, PCP-Ca had the greatest and significant effect on mineralization of MC3T3-E1 cells (P < 0.05). These results suggested that phosphorylation is a promising method to improve the calcium binding capacity and osteogenic activity of collagen peptides. [ABSTRACT FROM AUTHOR]

This study was focused on the differences between three concentrations of four safe bio-active volatile terpenes and natural compounds (trans-cinnamaldehyde, thymol, menthol, and vanillin) on the egg yolk volatile components. In which, Headspace Solid phase Micro Extraction (HS-SPME) followed by GC/MS were used for volatiles analysis, and electronic nose (E-Nose) with 18 sensors was used for the aroma pattern. In the results, a total of 111 different volatile compounds were identified by using GC/MS. Some ketones, amines, nitro and organic acid compounds such as hexanone were significantly reduced after using these compounds. On the other hand, first principal components (PC1) of trans-cinnamaldehyde (0.1%) was decreased significantly (p <.05) to −4.8 ± 0.8, compared to the control with 4.3 ± 2.1. And, it increased benzaldehyde and nonanal peaks area significantly to 46.56 ± 14.46 and 9.22 ± 4.81 MPA. In menthol (0.1%), the content of d-limonene was decreased to 4.65 ± 0.49 MPA, compared to the control with 14.16 ± 4.95 MPA. On the other hand, by E-Nose, vanillin (0.1%) PC1 was decreased significantly to −4.48 ± 0.43. Moreover, thymol (0.1%) decreased hydrocarbon sensation to 0.448 ± 0.005. And, vanillin (0.1%) decreased hydrogen sulfide and ketones sensation to 0.169 ± 0.01 and 0.344 ± 0.01, respectively. In conclusion, this study is providing novel information to understand the effects of bio-active molecules on the biological fatty media volatility. Also, it explains how terpenes can protect egg yolk media from the unacceptable odor formation which results from the degradation of its lipids and proteins. Unlabelled Image • One hundred eleven different volatile compounds were found by HS-SPME-GC/MS. • Hexanal, nonanal, and benzaldehyde showed positive volatiles PC1 and negative PC2. • Trans-cinnamaldehyde and thymol significantly decreased yolk ketones. • Azulene was formed in trans-cinnamaldehyde and thymol (0.1%). • A significant negative correlation was found between PC1 of volatiles and E-nose. [ABSTRACT FROM AUTHOR]

Studies on the association between egg yolk (EY) consumption and obesity are limited and the involved mechanism still needs to be further explored. In this study, the effects of EY consumption under normal and high fat diets on mice based on lipidomics approach is compared. A total of 893 and 925 individual lipid species are determined in serum and liver, respectively. The results reveal that EY can alleviate the hyperlipidemia in HFD‐induced obese mice by increasing serum high‐density lipoprotein cholesterol (HDL‐C) and neutral glycerolipid, hepatic fatty acids (FAs), and the size of adipose tissue cells. OPLS‐DA and S‐plots show that 29 lipid biomarkers in serum, mainly including phosphatidylcholine (PC), triglyceride (TG), and phosphatidylinositol (PI), and 44 lipid biomarkers in liver including TG, lysophosphatidylcholine (lysoPC), and lysophosphatidylethanolamine (lysoPE) are related to obesity caused by HFD. In addition, the regulation of EY on lipid disorders is mainly related to the decreases in serum TG and PC, and hepatic fatty acids (FAs), TG and diacylglycerol (DG), which is closely associated with glycerophospholipid metabolism. These findings suggest that long‐term treatment of EY consumption may not increase NAFLD risk factors in normal diet‐fed mice, further improving the hyperlipidemia in HFD‐induced mice. Practical Applications: This study investigates the overall effects of EY on normal and high‐fat diet by lipidomic analysis. It is concluded that the intake of EY can improve the hyperlipidemia in HFD‐induced obese mice by improving glycerophospholipid metabolism. These results facilitate to comprehensively evaluate the nutrition of EY and help elucidate the favorable effect of eggs. The flow chart of the egg yolk nutritional evaluation based on 100‐d mice experiment. The lipid profiles in serum and liver are further investigated using UPLC‐MS/MS method to elucidate its favorable effect on lipid metabolism. [ABSTRACT FROM AUTHOR]

Background: Fatty acids have been shown to modulate intestinal cholesterol absorption in cells and animals, a process that is mediated by several transporter proteins. Of these proteins, Niemann-Pick C1-Like 1 (NPC1L1) is a major contributor to this process. The current study investigates the unknown mechanism by which fatty acids modulate cholesterol absorption. Methods: We evaluated the effects of six fatty acids palmitic acid (PAM), oleic acid (OLA), linoleic acid (LNA), arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on cholesterol uptake and transport in human enterocytes Caco-2 cells, and on the mRNA expression levels of NPC1L1, others proteins (ABCG5, ABCG8, ABCA1, ACAT2, MTP, Caveolin 1, Annexin-2) involved in cholesterol absorption, and SREBP-1 and SREBP-2 that are responsible for lipid metabolism. Results: The polyunsaturated fatty acids (PUFAs), especially for EPA and DHA, dose-dependently inhibited cholesterol uptake and transport in Caco-2 monolayer, while saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) had no inhibitory effects. EPA and DHA inhibited cholesterol absorption in Caco-2 monolayer might be caused by down-regulating NPC1L1 mRNA and protein levels, which were associated with inhibition of SREBP-1/− 2 mRNA expression levels. Conclusion: Results from this study indicate that functional food containing high PUFAs may have potential therapeutic benefit to reduce cholesterol absorption. Further studies on this topic may provide approaches to control lipid metabolism and to promote health. [ABSTRACT FROM AUTHOR]

In this study, a proteome analysis of Tibetan chicken egg yolk as well as the comparison to that of lowland chicken were performed by label-free quantitative proteomics. A total of 135 proteins were identified and abundances of 19 of these proteins were significantly different between these two groups. These differential proteins were mainly associated with oxidative stress, defense, energy metabolism and tissue development through bioinformatics analysis. To further verify the species-specific diversity of the antioxidant capacity, the antioxidative activities of egg yolk proteins were further invested in vitro and in Caco-2 cells. It was observed that both Tibetan and lowland chicken egg yolk proteins showed antioxidant activities, but the former exerted a much stronger effect. PIT54 and glutathione peroxidase 3 were considered to be antioxidant-related candidate proteins. These results provide substantial evidence for the molecular mechanisms of enhancing physical activity levels of egg yolk proteins, especially with regard to the cross-species protective mechanisms against oxidative stress. [ABSTRACT FROM AUTHOR]

This experiment was conducted to explore the differences of serum steroid hormones with age and sex in hen eggs during incubation periods for identification of males and females. The concentrations of estrone (E1), estradiol (E2), estriol (E3), testosterone (T), androstenedione (A4), and dihydrotestosterone (DHT) in serum were measured by enzyme-linked immunosorbent assays in chicken embryos on 8, 10, 12, 14, and 16 D, respectively. During the development of chicken embryo, egg weight loss was closely related to age but no sex. However, it was found that both age and sex significantly affected hormones and had obviously more effect on androgens levels. Besides E2 and T, other steroids such as E1, A4, and DHT were also significantly correlated with sex (P < 0.05). Notably, the level of T and the ratio of T to E2 were significantly higher in males than females (P < 0.05). The ratio of E1 to E2 displayed different trends in different sexes, which increased in males but decreased in females. The distribution proportions of androgens and estrogens kept stable level during the late hatching periods of 12 to 16 D. The sex differences of steroids were more obvious at the late hatching stage through PCA. These suggested that the serum hormones differences in male and female embryos played a vital role in sexual differentiation. These findings not only provided the theoretical basis for sex determination of fertilized eggs in egg-laying hen strains, but also contributed to develop a non-invasive way to sex determination of fertilized eggs to meet the modern commercial application. [ABSTRACT FROM AUTHOR]

Maintaining homeostasis is of utmost importance regarding human health. Several factors could protect human body's internal environment from harms and fluctuations from external environment. Regulation of physiological pH has a considerable role in maintaining human health and its metabolic functions. Several studies have shown that the interstitial body fluid pH around metabolic tissues is easily reduced due to weaker pH buffering capacity than that in the cytosol and blood circulation. Therefore, pH reduction in the interstitial fluid may cause the onset of metabolic dysfunctions. However, several dietary food components have potential benefits in maintaining the interstitial fluid pH to the normal range by improving buffering capacities, suppressing proton production, and activating proton transporters, which strengthen the effect of appropriate diet on metabolic health. Keeping deep insights about this aspect, we have summed up several facts and figures for maintaining human body homeostasis via regulation of physiological pH. Furthermore, we have discussed about different food categories and their potential renal acid load and its relation with maintaining homeostasis. Afterwards we have deeply discussed the potential beneficial role of healthy food components in different pathological conditions of human body. [ABSTRACT FROM AUTHOR]

Preserved eggs are traditional alkali‐pickled food in China and have been enjoyed by consumers and extensively studied by researchers for their nutritional tastes and their anti‐tumor, anti‐inflammatory, antioxidant, lipid‐lowering, and blood pressure‐lowering properties. To study the anti‐tumor effects of preserved eggs, this project observed the health on rats, and anti‐tumor effects and separated anti‐tumor active components on HT‐29 cells. SD rats fed for 80 days showed that preserved eggs had no significant effect on weight, food intake, blood pH, liver tissues, or organ indices. Preserved eggs significantly increased blood levels of oxidative stress markers SOD and CAT, decreased MDA levels by 0.46, 0.23, and 0.25 times. Moreover, they also increased the level of IL‐2 from 1233 to 1340 pg/mL. Two water‐soluble bioactive peptide fractions, B1 and B2, with molecular weights ≥10 kDa were further obtained from preserved eggs by ultrafiltration and Superdex Peptide 10/300 GL. The potential mechanism of B1 and B2 is to activate the internal mitochondrial apoptotic pathway and induce apoptosis by up‐regulating the expression of the pro‐apoptotic factors cytochrome C, caspase‐3, and caspase‐9 mRNA in HT‐29 cells. [ABSTRACT FROM AUTHOR]

One unresolved challenge in the egg industry is how to efficiently and non-invasively detect unfertilized eggs prior to incubation. This detection ability would not only significantly improve hatching rates and reduce costs but also conserve incubator space and prevent poor-quality embryos from contributing to the spread of infections. This study demonstrates a procedure for distinguishing between fertilized and unfertilized eggs prior to incubation by studying the respiratory differences between fertilized and unfertilized eggs using the Non-invasive Micro-test Technique (NMT). A customized micro-testing examination platform, NMT Egg Testing System (NMT-ETS) was constructed for the real-time monitoring of the intensity and rate of oxygen exchange between the egg and its external environment. The results from this study revealed that at room temperature, there is a significant difference in gas exchange rates between fertilized and unfertilized eggs. The results indicate that the oxygen flux of fertilized eggs exceed 20 pmol/(cm2·s), whereas unfertilized eggs show a much lower oxygen flux. Based on the results, the NMT method can be used to effectively distinguish between fertilized and unfertilized chicken eggs. [ABSTRACT FROM AUTHOR]

Chitin is the most abundant natural amino polysaccharide, showing various practical applications owing to its functional properties. However, there are barriers in the development due to the difficulty of chitin extraction and purification, regarding its high crystallinity and low solubility. In recent years, some novel technologies such as microbial fermentation, ionic liquid, electrochemical extraction have emerged for the green extraction of chitin from new sources. Furthermore, nanotechnology, dissolution systems and chemical modification were applied to develop a variety of chitin-based biomaterials. Remarkably, chitin was used in delivering active ingredients and developing functional foods for weight loss, lipid reduction, gastrointestinal health, and anti-aging. Moreover, the application of chitin-based materials was expanded into medicine, energy and the environment. This review outlined the emerging extraction methods and processing routes of different chitin sources and advances in applying chitin-based materials. We aimed to provide some direction for the multi-disciplinary production and application of chitin. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, ovalbumin (OVA) was phosphorylated by dry-heating at three different pH values (5.0, 7.0 and 9.0) and 45 °C for 12 h in the presence of sodium tripolyphosphate (STP). The results indicated that, when compared with native OVA (N-OVA), the zeta potential absolute value of phosphorylated OVA (PP-OVA) increased from 2.13 mv (N-OVA) to 13.57(PP-OVA-pH5.0), 16.00(PP-OVA-pH 7.0) and 11.20 mv (PP-OVA-pH 9.0); the volume-weighted mean diameter (D [4,3])of emulsions stabilized by the N- and PP-OVA decreased from 70.22 μm (N-OVA) to 37.16(PP-OVA-pH 5.0), 16.21(PP-OVA-pH 7.0) and 43.52 μm (PP-OVA-pH 9.0); and PP-OVA emulsions exhibited a more narrow monomodal size distribution and a smaller particle size than those of N-OVA, with the corresponding emulsifying activities index (EAI) increased from 92.71(N-OVA) to 142.51(PP-OVA-pH5.0), 224.88(PP-OVA-pH 7.0), and 150.97(PP-OVA-pH 9.0), respectively. The microscopic observation showed that the emulsion droplets of PP-OVA were more densely and uniformly distributed than those of N-OVA. Furthermore, characterization of PP-OVA by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and 31 P nuclear magnetic resonance ( 31 P NMR) revealed that phosphate groups were bound to the -OH on serine and threonine and the -NH 2 on lysine and arginine, with covalent interactions (C–O–P and C-N-P bounds) formed between OVA and STP. This study demonstrated that the introduction of phosphate groups could increase the amount of negative charge and intermolecular repulsion, decrease the particle size of droplets and improve the emulsifying ability of PP-OVA. [ABSTRACT FROM AUTHOR]

[Display omitted] • SEW improved the texture properties of steamed bread. • SEW is utilised as a sustainable ingredient in steamed bread formulations. • Micromorphology showed a compact and smooth structure after adding SEW. • Enrichment of steamed bread with 15% SEW shows significant acceptability. Steamed bread has long been an important part of Chinese cuisine. This study investigated the effects of salted egg white (SEW) (5, 10, 15, and 20% w/w) on the quality of steamed breads. Findings revealed that SEW notably enhanced the bread's volume and texture, with a 20% inclusion significantly boosting water retention and rheological properties, albeit reducing bread's lightness. In addition, the H-bond absorption band intensity in the Fourier transform infrared spectroscopy (FTIR) analysis showed increased peak intensities with higher SEW levels, indicative of protein structure alterations. X-ray diffraction confirmed the presence of an amylose–lipid complex. Scanning electron microscope (SEM) and Confocal laser scanning microscope (CLSM) imaging depicted a smooth, consistent protein network with SEW addition. Consumer sensory evaluation responded favourably to the SEW15 steamed bread, suggesting its potential for food industry application. Overall, the study considers SEW an effective ingredient for improving steamed bread quality. [ABSTRACT FROM AUTHOR]

This study prepared emulsion gels by modifying ovalbumin (OVA)-flaxseed oil (FSO) emulsions with transglutaminase (TGase) and investigated their properties, structure and oxidative stability under different enzyme reaction times. Here, we found prolonged reaction times led to the transformation of α-helix and β-turn into β-sheet and random coil. The elasticity, hardness and water retention of the emulsion gels increased significantly, but the water-holding capacity decreased when the reaction time exceeded 4 h. Confocal laser scanning microscope (CLSM) indicated extended enzyme reaction time fostered oil droplet aggregation with proteins. Emulsion gel reduced FSO oxidation, especially after 4 h of the enzyme reaction, the peroxide value (PV) of the emulsion gel was reduced by 29.16% compared to the control. In summary, the enzyme reaction time of 4 h resulted in the formation of a dense gel structure and enhanced oxidative stability. This study provides the potential applications in functional foods and biomedical fields. [Display omitted] • A novel FSO - encapsulated emulsion gel was constructed by inducing OVA with TGase. • Extended enzymatic reaction time improved emulsion gel properties and structure. • TGase - treated OVA aggregated more on the surface of the oil droplets. • Emulsion gel enhanced the oxidative stability of FSO during storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel chitinase EaChi40 was isolated from Exiguobacterium sp., and its gene was expressed in E. coli BL21 (DE3). • Recombinant chitinase EaChi40 showed good cold-adapted catalysis and thermal stability. • Crayfish shell was treated with ball milling and ultrasonic-assisted decolorization to promote enzymatic hydrolysis. • EaChi40 effectively bio-transformed crayfish shell chitin by producing chitin oligosaccharides. Crayfish have become a heavily consumed food and its chitin-rich shell is of great value in terms of waste conversion. This study found a novel chitinase (EaChi40) from a marine bacterium Exiguobacterium antarcticum. The gene was cloned and expressed as a soluble protein of 40 kDa, having optimal activity at pH 6.0 and 30 °C. EaChi40 showed good stability and high specific activity, and kinetic studies found K m and V max were 0.86 mg/mL and 13.66 μmol/min/mg. For conversion crayfish shell into oligosaccharides, ball milling and ultrasound-assisted hydrogen peroxide decolorization were applied to pretreat crayfish shell to facilitate its hydrolysis. After the enzymatic conversion, the hydrolysis products of chitobiose and N-acetyl-D-glucosamine were 9.09 mg/mL and 9.21 mg/mL, respectively. EaChi40 efficiently degraded crayfish with a high hydrolysis rate of 76.1%. It is expected to be a good candidate for the production of chitin oligosaccharides in the food and biological fields. [ABSTRACT FROM AUTHOR]

Phosvitin (PV) is the main phosphoprotein in egg yolk, with the highest degree of phosphorylation known in nature. The PV and resveratrol (Res) can form a complex, thus effectively improve the solubility of Res. In this work, the interaction between Res and PV was investigated by the fluorescence spectroscopy and molecular docking. The fluorescence emission intensity of PV became weak along with a red shift when it interacted with Res and the antioxidant activity was enhanced. The quenching constants of the interaction systems were 1.12×104 M–1 and 9.40×103 M–1 at 25°C and 35°C, respectively, which indicated the presence of static quenching phenomena between them. The binding constant was 1.80×104 M–1, and the number of corresponding binding sites was approximately equal to one. The thermodynamic results revealed the combination was spontaneous, and the change of enthalpy and entropy was ∆H = 53.50 kJ/mol, ∆S = 261.00 J/mol·K, respectively. It indicated that the interaction forces between Res and PV were mainly hydrophobic interaction and hydrogen bonding. Molecular docking showed the binding mode, which was consistent with the experiment results. The research on the interaction between Res and PV provided theoretical guidance for the application of Res in food. Practical Application: PV is the most highly phosphorylated protein in nature and has pro‐calcium absorption effects. Res is a polyphenol with strong antioxidant and anti‐inflammatory activity, but its poor solubility limits its application. In this study, the solubility of Res was considerably enhanced by compounding Res and PV, and the antioxidant activity of Res was well retained. It increases the value of Res in food and other applications and opens up new possibilities for processing and utilization of PV. [ABSTRACT FROM AUTHOR]

BACKGROUND: Respiration is an important physiological activity of eggs and is closely related to their freshness. To further observe the diffusion of carbon dioxide released by egg respiration, we used a respirometer to measure the respiration parameters of eggs stored at room temperature and performed a respiration simulation using Fluent software. This paper also explores the relationship between respiratory intensity, freshness, and storage period. RESULTS: The results demonstrate that the diffusion of carbon dioxide released from the respiration of eggs is related to the characteristics of heavy gas diffusion. By comparison, the simulated value (0.0199 m s−1) is close to the experimental value (0.0208 m s−1), which indicates that the simulation and analysis results are valid. In addition, the logarithmic model was used to assess the relationship between respiration intensity, Haugh unit, and the yolk index (R2 values 0.89 and 0.87). The R2 of the relationship between the real and the predicted Haugh unit value and the yolk index are 0.9 and 0.84 respectively, indicating that the model is a good fit. The equivalent egg age model was established using nonlinear regression, where the correlation coefficient R was 0.888 and P < 0.01, indicating it was both stable and reliable. CONCLUSION: The standard k–ε model is suitable for egg respiration simulation analysis. Respiratory intensity can be used as a potential index for nondestructive testing of egg freshness, which is a new method for nondestructive testing of egg freshness and storage period. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Summary: Heat treatment will affect the nutritional properties and potential bioactivity of food materials. The aim of this work was to evaluate the effect of different thermal treatment (4, 56, 65 and 100 ℃) and invitro gastrointestinal digestion on the antioxidant activity of egg white hydrolysate. The results demonstrated that egg white hydrolysate treated at 65 ℃ exhibited the highest antioxidant. Remarkably, the simulated digestion significantly increased antioxidant activity of egg white hydrolysate. Furthermore, we identified twenty‐four potential antioxidant peptides by performing mass spectrometry and bioinformatic analysis. Six peptides were selected based on the activity prediction score of the online tool. The results showed that P6 (ACPECPK) possessed the most outstanding antioxidant properties and had low cytotoxicity and allergenicity. Bioinformatics technology combined with biochemical assays may offer a way for discovering novel antioxidant peptides from different kinds of food under various heat treatment conditions. [ABSTRACT FROM AUTHOR]

Abstract: The avidin–biotin interaction was evaluated systematically by fluorescence spectroscopy under different conditions of temperature, pressure, pH, metal ions, incubation time and initial avidin concentration. The binding constant was calculated according to the modified Stern–Volmer equation, which deduced the existence of static quenching mechanism. The data obtained revealed that avidin–biotin interaction exhibited temperature, pH, metal ions, incubation time and initial avidin concentration sensitivity. The binding constants decreased with increase in temperature, while the binding sites were independent of temperature. The values of thermodynamic parameter ΔH (−149.85kJmol−1) and ΔS (−284.26Jmol−1 K−1) suggested hydrogen bonds and van der Waals played a major role in the reaction. The binding constants between avidin and biotin increased firstly and then decreased gradually with the increase of pH values. Metal ions can also affected the binding constants between avidin and biotin. The association kinetics firstly acquired by the combination of the change in fluorescence per unit time and the modified Stern–Volmer equation indicated that the reaction time required to reach equilibrium was 2200s, and the average reaction rate for the binding process was very high in the first 180s. Reaction of the avidin in the first 180s was more than 40% of the total avidin involved in the whole process. [Copyright &y& Elsevier]

Abstract: A new method for determination of lysozyme with high sensitivity based on Resonance Rayleigh scattering (RRS) by using Au nanoparticles as a probe was proposed in this experiment. The RRS spectrum, nonlinear scattering (second-order scattering (SOS), frequency doubling scattering (FDS)) spectra and absorption spectrum of the Au nanoparticles–lysozyme system have been analyzed. In addition, the effects of several factors on scattering intensities were investigated, including pH value of solution, amount of Au nanoparticles, mixing sequence of each reagent and the coexisting substances. The results showed that the coexisting substances have little influence on the RRS intensities of the systems. Moreover, the possible mechanism for the RRS enhancement of Au nanoparticles–lysozyme system was preliminary discussed. The RRS method for determination of lysozyme has good sensitivity and selectivity with the detection limits 30.1ng/ml. The contents of lysozyme were determined with recoveries of 98.2–105.4% and relativity relative standard deviation (RSD) of 0.3–3.7%, respectively. It proved that the method established in our study is suitable for the determination of lysozyme in synthetic sample and natural chicken egg white sample. [Copyright &y& Elsevier]

The foaming property of egg white (EW) is essential in food processing. In this study, we investigated the effect of ultrasound combined with adding different concentrations (0, 0.4, 0.5, 0.6, 0.7, and 0.8 %, m/v) of flaxseed gum (FG) on EW foaming. The results showed that the cooperation of ultrasound treatment and FG significantly improved the foaming stability. Regarding details, FG reduced the sulfhydryl content and surface hydrophobicity of EW proteins while increasing the average particle size and PDI value. Despite the ultrasound treatment, FG significantly improved the foaming stability from 62.83% to 99.82% (p < 0.05). Based on the analysis of ξ-potential, surface tension, rheology, etc., FG improved the EW microenvironment, which is conducive to foaming stability. As a new type of polysaccharide, FG combined with ultrasound can significantly improve the foaming properties. This research could solve the problem of reduced foaming stability of EW treated by ultrasound alone, making promising applications in the food industry. [Display omitted] • Ultrasound combined with flaxseed gum improved the foaming of egg white. • Flaxseed gum overcame the problem that ultrasound reducing the foaming stability. • Flaxseed gum formed a viscoelastic interfacial film to increase surface tension. • Egg white protein's structure was more compact and increased foaming stability. [ABSTRACT FROM AUTHOR]

Respiration plays a crucial role in the physiological development of embryos throughout the entire incubation process and serves as a vital indicator for discerning unfertilized eggs and embryos that have stopped development. This article explores the relationship between egg respiration, fertilization status, and chicken embryo viability. First, it studied the changes in respiration of fertilized and unfertilized eggs during the early stages of incubation (Day 1–3) and found that the CO 2 production of fertilized eggs gradually increased, while those of unfertilized eggs gradually decreased. Moreover, significant differences in respiration between fertilized and unfertilized eggs were observed on the second day of incubation. Next, we employed Random Forest (RF), Logistic Regression (LR), and Support Vector Machine (SVM) models to differentiate between fertilized and unfertilized eggs. Notably, the SVM algorithm exhibited exceptional performance in discriminating between fertilized and unfertilized eggs, achieving a remarkable test set accuracy of 98.41 %. Finally, a Bayesian algorithm was applied to classify embryos as either dead, weak, or viable in middle and later stages of incubation. Bayesian discriminant analysis yielded compelling results, achieving a 100 % detection rate for deceased embryo eggs. The outcomes of this study provide a robust theoretical foundation and empirical data to advance non-destructive testing methodologies for poultry eggs. Graphic abstract. [Display omitted] • Identification of weak and dead embryo based on respiration. • Respiration analysis of fertilized and unfertilized eggs. [ABSTRACT FROM AUTHOR]

• HPCD process affect liquid whole egg quality as well as disposal of sterilization. • HPCD process promoted interfacial properties of liquid whole egg. • The physicochemical properties of protein were changed by HPCD. • The apparent viscosity of LWE declined after HPCD treatment. In this research, the impact of High Pressure Carbon Dioxide (HPCD) on the physicochemical, interfacial and rheological properties of liquid whole egg (LWE) was investigated. HPCD treatment increased the solubility, free sulfhydryl groups and surface hydrophobicity of LWE. The highest foaming ability (186%) and foaming stability (72%) were obtained at 60 min of HPCD treatment, which were 1.3-fold and 1.4-fold those of the control group (147% and 51%, respectively). Compared with the control group, the LWE emulsion had a minimum particle size (16.3 μm) when the treatment time was 75 min, and the highest absolute value of zeta potential reached 7.66 mV when the processing time was 60 min. HPCD treatment decreased the apparent viscosity of LWE at a low shear rate. Dynamic viscoelastic characteristics indicated that both the G' and G" moduli of LWE under the HPCD process were lower than those of the control group at any frequency. [ABSTRACT FROM AUTHOR]

• The chitosan and eggshell membrane powder composite macroparticles were prepared. • The eggshell membrane powder increased the porosity of chitosan macroparticle. • The eggshell membrane powder improved the activity sites for enzyme immobilization. • The increase in pore size could improve the activity of immobilized protease. Chitosan-based macroparticle is a common carrier for enzyme immobilization applied in food industry. Driven by the requirement of large carrier pores for the biomacromolecular substrates such as protein, the eggshell membrane powder (ESMP) was employed as multifunctional porogen to improve the physicochemical structure of chitosan-based macroparticles. The prepared macroparticles were characterized by SEM, XRD, FTIR, Raman spectroscopy, nitrogen adsorption-desorption isotherms, and thermogravimetric analysis. The results showed that an increase of ESMP percentage could improve the porosity of macro holes in macroparticles, and it also enlarged the size of mesopores. Moreover, the ESMP significantly increased (P < 0.05) the amount of papain immobilization, whereas the specific activity of immobilized papain achieved a maximum value of 871.95 U/mg at CSESM2 and then declined with the increase of ESMP. Therefore, the inclusion of 20 % ESMP in chitosan-based macroparticles gave the highest activity of its immobilized protease. [ABSTRACT FROM AUTHOR]

Camel meat is presented as a primary source of nutritional supplement for fulfil human's nutritional needs in Arabian, African, and in some Asian countries, particularly in areas where weather is hot. In this study, the proximate compositions and microbial property of camel meat was compared with beef, mutton and chicken by analyzing the contents of moisture, total fat, crude protein, minerals, vitamins, amino acids and fatty acids. The results revealed that camel meat has higher (P < 0.05) moisture, minerals, vitamins and amino acids content but lower total fat, cholesterol, and ash content than other meats. The results also found that camel meat has lowest total microbial count (TBC) and it was free from pathogenic bacteria as compared to other meats. Moreover, camel meat was better in all the examined samples and healthier for human consumption. These results suggested that camel is a low-fat, nutritious and safe meat. • Camel meat has high moisture, minerals, vitamins, and amino acids than other meats. • Camel meat has less cholesterol, lowe TBC , and free from pathogenic bacteria. • Camel meat is better in all the examined samples and healthier for a human. • Meat quality maintained at a constant low temperature to avoid freeze-thaw cycles. • The nutritional value of camel meat is much better than other animal's meats. [ABSTRACT FROM AUTHOR]

Hydrogels could be used as wound dressings, but most protein-based hydrogels lack anti-bacterial effects. Here, we successfully prepared a silver ion cross-linked thiolated protein hydrogel (thiolated Ovalbumin and Gelatin, O3G7). The wound photographs showed that the healing rate (96.23 %) of hydrogel-treated mice was higher than the control group. Meanwhile, the hydrogel increased the granulation tissue's total protein content. Furthermore, it significantly increased the collagen content, consistent with the results of Masson's trichrome (MT) staining and immunohistochemical analysis of type I collagen (Col I). The results of hematoxylin and eosin (H&E) staining showed the growth and proliferation of inflammatory cells, granulation tissue, fibroblasts, blood vessels and hair follicles in acute wounds. O3G7 hydrogel had fewer inflammatory cells and more neovascularization, and hair follicle tissue and intact epidermis could be observed. The results of immunofluorescence and immunohistochemistry showed that the O3G7 group reduced the expression of tumor necrosis factor (TNF)-α (56.87 % of the control group) and upregulated the expression of transforming growth factor (TGF)-β (1.29 times of the control group). These results suggest that O3G7 hydrogel significantly affects the healing of acute wounds. This study demonstrates that hydrogels prepared from food-derived proteins will be promising and bio-safe candidates in bioengineering. [Display omitted] • Silver icon brought the general protein-based hydrogel with antibacterial activity. • The thiolated protein hydrogel has both a dense structure and excellent biocompatibility. • The tOVA/tGel@Ag hydrogels accelerate the healing of acute wounds in mice observably. [ABSTRACT FROM AUTHOR]

Preserved egg, a traditional Chinese egg product, is regarded as an anti-inflammatory food in traditional Chinese medicine. This study was aimed to examine anti-inflammatory effect of the simulated gastrointestinal digestive products of whole preserved egg (DWPE), preserved egg white (DPEW), and preserved egg yolk (DPEY) on lipopolysaccharide (LPS)-stimulated RAW264.7 cells. The results demonstrated that DWPE, DPEW, or DPEY inhibited the LPS-induced secretion of Nitric oxide (NO), without marked cytotoxicity. The DWPE, DPEW, and DPEY significantly suppressed the secretion of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6. Particularly, the inhibition rate of DPEW on NO, IL-6, and TNF-α could reach 25 to 27%, 31 to 42%, and 26 to 38%, respectively (P < 0.05). Furthermore, the DPEW and DPEY downregulated the gene expression of Cyclooxygenase-2 and inducible nitric oxide synthase in a dose-dependent manner. Taken together, this study indicated that DWPE, DPEW, and DPEY, especially DPEW, might serve as functional food for anti-inflammatory therapy. [ABSTRACT FROM AUTHOR]

• Nano-TiO 2 has enhanced properties of the pullulan film. • The WVP value of film was obtained minimally at 6.6 × 10−4 g m/m2 h KPa. • The TS value of film was obtained maximally at 15.99 MPa. • The ability of the blend film to block UV has been significantly improved. In this study, effects of nano-TiO 2 on the microstructural, physical, mechanical and optical properties of pullulan films were investigated. The results showed that the addition of nano-TiO 2 improved the water vapor barrier properties of the film due to the tortuous path formed by nano-TiO 2. When the concentration of nano-TiO 2 was 0.04 g/100 mL, the tensile strength of the film showed a maximum value (15.99 MPa). The elongation at break of the film continued to decrease with the increase of nano-TiO 2. The TEM analysis showed that higher concentration of nano-TiO 2 would cause greater aggregation. Meanwhile, the results of FTIR and low-field NMR indicated that the miscibility between pullulan and nano-TiO 2 was due to the formation of intermolecular hydrogen bonds during film formation. Furthermore, the addition of nano-TiO 2 significantly improved the film barrier properties to ultraviolet light. [ABSTRACT FROM AUTHOR]

High-density lipoproteins from egg yolk (EYHDL), also called lipovitellenin, is the second largest constituent of egg yolk (EY), and possesses important functional properties in lipid metabolism for its high content of phospholipids. To better understand its lipid profile, a lipidomic analysis based on ultrahigh-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) and gas chromatography and mass spectrometry (GC–MS) was conducted. Compared with EY, the lower level of triglyceride (TG), higher level of phosphatidylcholine (PC), phosphatidylinositol (PI), and diglyceride (DG) were found in EYHDL (p < 0.01). The orthogonal partial least squares-discriminant analysis (OPLS-DA) revealed that the lipid profile of EYHDL was clearly discriminated from EY. Volcano plots combined with S-plots showed that the differential lipids in EYHDL were 22 significantly downregulated TG with long-chain fatty acids in ES+ , and 30 markedly upregulated lipids including PC, phosphatidylethanolamine (PE), and PI with long-chain fatty acids in ES− (p < 0.01). GC–MS analysis showed higher level of C18:1 and C22:6, and lower level of C16:0 in EYHDL than EY. In summary, EYHDL could serve as a favorable lipid source for human diets for its higher PC, PI, and lower TG. [ABSTRACT FROM AUTHOR]

• Genipin and glutaraldehyde could transform into polymer and dimer, respectively. • Hydrogen bonds could improve the density of the network structure of FILM-GEs. • Polymerization of genipin greatly affected the swelling ratio of FILM-GEs. • Chitosan based film crosslinked by genipin had better mechanical properties. In this study, genipin and glutaraldehyde in varied concentrations were utilized in chitosan crosslinking under alkaline condition. A UV/Vis analysis was used to investigate the molecular structure of genipin and glutaraldehyde in an aqueous alkaline solution. The results showed the formation of glutaraldehyde dimer and polymerized genipin. The FTIR-ATR, SEM, DSC, XRD, mechanical properties, crosslinking degree and swelling ratio of chitosan based films crosslinked by genipin and glutaraldehyde were determined. The results indicated that the hydrogen bonds formed between genipin and chitosan enabled the films crosslinked by genipin (1 and 5 mmol/L) to have a higher degree of crosslinking, but a lower swelling ratio than glutaraldehyde (1 and 5 mmol/L). Genipin enabled the chitosan-based film to possess better mechanical properties and crystallinity than glutaraldehyde. The polymerization of genipin had a substantial effect on the network structure and swelling behavior of chitosan-based films crosslinked by genipin. [ABSTRACT FROM AUTHOR]

Abstract In this study, ovalbumin (OVA) was phosphorylated under wet-heating in the presence of sodium tripolyphosphate at pH 6.0 and 60 °C for 1, 2, 3, 4 and 5 h, and the structural and physical properties of phosphorylated OVA (P-OVA) were investigated. The FT-IR spectrum confirmed the covalent attachment of the phosphate group to OVA. New possible phosphate sites (Ser-221, Ser-269, Tyr-281 and Ser-324) were detected by using liquid chromatography in tandem with mass spectrometry. Circular dichroism (CD) spectra demonstrated that P-OVA molecular became more flexible and disordered. The decreased fluorescence intensity indicated that the chromophore microenvironment became more exposed and polar because of conformational changes. The surface hydrophobicity (H 0) and the absolute value of zeta potential of P-OVA obtained at 5 h was 1.8 and 1.5 times higher than that of N-OVA. Foaming ability (FA) and foaming stability (FS) were enhanced by 1.7 and 4.4 times after wet-heating phosphorylation for 4 h, which were up to 87.0% and 28.5%, respectively. Furthermore, the correlation analysis suggested that FA was significantly correlated to random structure (P < 0.01) and H 0 (P < 0.01), and zeta potential was related with FS (P < 0.05). Graphical abstract Image 102 Highlights • Ovalbumin was phosphorylated by sodium tripolyphosphate under wet-heating. • Possible phosphate sites were detected by LC-MS/MS. • Structural changes were confirmed by fluorescence and CD spectrum. • H 0 and the absolute value of zeta potential increased after the phosphorylation. • Foaming ability and stability were promoted by phosphorylation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Film forming solutions were analyzed using LF-NMR and rheometer. • Nanosilica improved the operating performance of chitosan-based film. • Nanosilica increased the density of chitosan network through hydrogen bonds. • The excessive aggregation of nanosilica destroyed the structure of composite films. Abstract Chitosan based organic-inorganic composite films were prepared through direct incorporation of nanosilica particles in order to enhance their performance for potential packaging material. After the addition of nanosilica, the viscosity of film-forming solutions (FFSs) decreased obviously, and the G' of FFS with 25% of nanosilica was higher than that of other FFSs with nanosilica. In low field nuclear magnetic resonance (LF-NMR) determination, the addition of 25% of nanosilica gave rise to the lowest relaxation time and peak area proportion of T 21 component. Additionally, the changes of structure characteristic of composite films with different nanosilica content were analyzed through FTIR spectroscopy, SEM and XRD analysis. The thermal stability of films improved markedly with increasing nanosilica. The optimal mechanical properties of films were yielded at 25% of nanosilica. Furthermore, the introduction of nanosilica significantly (p < 0.05) decreased the swelling ratio of chitosan based films at pH 7.6 and pH 2.6. [ABSTRACT FROM AUTHOR]

As a promising non-thermal decontamination technique, γ-irradiation has been practically used to ensure microbial safety of meat and meat products, but its effects on the properties of meat have not yet been fully understood. So, this study mainly investigated the effects of different doses irradiation (0, 3, 5 and 7 kGy) on the muscle protein conformation, surface hydrophobicity, solubility, particle size, turbidity and thermal stability. The results of CD spectroscopy showed that 3 kGy disrupted the beta-sheet to form unordered structures in SP while increasing dose level recovered the ordered structures in SP, especially the increased alpha-helix content of SP after 7 kGy irradiation. In case of MP, beta-turn exhibited a dose-dependent reduction and 7 kGy irradiation resulted in a dramatic increase in beta-sheet compared with MP control ( P  < 0.05). The DSC and SDS-PAGE results indicated that 3 kGy irradiation could promote the actomyosin formation in MP, but ≥5 kGy irradiation favored its depolymerization. And after irradiation, the solubility and particle size of SP was reduced significantly ( P  < 0.05). Consequently, turbidity of SP and MP reached their maximum value at 5 kGy and 3 kGy irradiation, respectively. Upon irradiation, WHC of both SP and MP gels dropped significantly ( P < 0.05) with increasing dose level. Rheological analysis demonstrated that, during thermal gelation, the G′ and G″ of SP decreased as irradiation dose increased due to greater protein denaturation. Microrheological behavior and Turbiscan results showed that irradiated SP samples exhibited significantly higher TSI compared with SP control, but ≥5 kGy irradiation exhibited a stronger EI and MVI value in MP, indicating the enhanced inter-droplet resistance force inside MP. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of the natural safety high antimicrobial compounds on egg yolk protein structure and function. Three different concentrations have been evaluated from: trans-cinnamaldehyde, thymol, menthol or vanillin on egg yolk by measuring the antimicrobial activity, Fourier transform infrared (FT-IR), secondary protein structure, surface hydrophobicity, zeta-potential, foaming and color properties. Results showed that by mixing yolk with 0.1% of thymol and trans-cinnamaldehyde, the antimicrobial activity increased significantly ( P < 0.05) to 92.18 ± 3.26; 98.95 ± 3.16 Inh% against Salmonella typhimurium and 103.30 ± 4.58; 101.34 ± 1.82 Inh% against, E. coli . Also, from the results of FT-IR and Circular dichroism, trans-cinnamaldehyde, thymol and menthol (0.1%) changed yolk α-helix protein significantly (34.00 ± 0.85; 34.05 ± 0.21 and 34.15 ± 0.35) % compared to the control (32.70 ± 0.14) %. Meanwhile, the surface hydrophobicity and foaming capacity increased and zeta-potential decreased significantly as a result of terpene-protein cross-link formation by using these bio-active compounds. However, the foaming stability of trans-cinnamaldehyde (0.1%) decreased significantly after 30 and 60 min. Menthol (0.05, 0.1%) showed the most effects on color properties in which the lightness increased to 83.24 ± 0.27 and 83.67 ± 0.14 compared to the control (80.15 ± 0.44). Therefore, this study is opening new thinking idea about using the bio-active molecules in food hydrocolloidal field for enhancing their health ability. [ABSTRACT FROM AUTHOR]

The present study investigated the effect of different irradiation dose (0, 3, 5 and 7 kGy) on the emulsifying properties development of pork myofibrillar protein (MP) and sacroplasmic protein (SP). The results showed that emulsifying activities of SP was significantly impaired by the increasing irradiation dose, while that of MP were only observed to be significantly improved at 3 kGy irradiation ( P  < .05). The increasing irradiation dose caused the increase of SP carbonyl groups and the decrease of its sulfhydryl groups ( P  < .05), while 3 kGy irradiation decreased the carbonyl groups of MP and increased ζ-potential significantly ( P  < .05). LF-NMR results revealed that the water hydration in MP structure was dose-dependent. FT-IR data displayed that irradiation caused minor change of SP in the amide I region from 1700 to 1600 cm −1 , while ≥5 kGy irradiation significantly contributed to the denatured aggregated β-sheet components of MP. [ABSTRACT FROM AUTHOR]

During the egg storage, the change in structure of ovalbumin (OVA) was determined by spectroscopy of Fluorescence, Circular Dichroism and Fourier-Transform Raman. The relationships between the OVA properties and structure were also investigated in this study. Comparing with the consequence of Circular Dichroism and Fourier-Transform Raman spectra, it was obvious that the percentage of α-helix and β-sheet showed downward trends after storage. In contrast, the percentage of β-turn and random coil clearly presented raising trend. Furthermore, tryptophan residues were buried in a more hydrophobic environment. The emulsifying and foaming properties of OVA all decreased during the storage. Moreover, the correlation analysis indicated that β-sheet related to the emulsifying stability of OVA ( p < 0.01), α-helix related to the foaming stability ( p < 0.05) at the same time. This study provided new interesting idea for the study on the relationships between the structure and functional properties of protein during food storage. [ABSTRACT FROM AUTHOR]