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Camel milk is becoming increasingly popular among consumers due to its nutritional and medicinal benefits. However, challenges such as the harsh living conditions required for camels and the relatively low production when compared to cow milk affect the sales of camel milk. Nevertheless, fermented camel milk is an excellent carrier of probiotics, which not only maintain its positive characteristics but also provide additional benefits. In this study, we compared the pH, viable counts, insulin-like growth factor 1 (IGF-1) activity, and microrheological properties of untreated fermented camel milk (control group) and fermented camel milk treated with probiotics (Zhang group [ Lacticaseibacillus casei Zhang], V9 group [ Bifidobacterium lactis V9], and Mix group [Zhang + V9]). After the addition of probiotics, the fermentation time reduced, potentially decreasing the costs associated with large-scale camel milk fermentation. Finally, eight key metabolites were identified in camel milk and fermented camel milk, we observed that the post-fermentation levels of guanine were significantly higher in the probiotic groups, with the highest levels observed in the Mix group. The research provides a theoretical basis for preparation of probiotic fermented camel milk, and produces a product which can be used to for diabetes patients in the future. • Untargeted metabolomics revealed the fermented camel milk's diversity and dynamics. • Probiotic addition could reduce the loss of IGF-1. • L. casei Zhang and B. lactis V9 could mutually promote the content of guanine. [ABSTRACT FROM AUTHOR]

Ultrasound (US) is an innovative food processing technique that has gained significant interest for its role in modifying proteins. Our study focused on how different US time exposure influence the stability, interfacial structure, and rheological characteristics of whey protein infused with milk fat globule membrane (MFGM). Results indicated that a 9-min ultrasound treatment (US-9) of protein, yielding an emulsion with particle size of 338.3 nm and ζ-potential of −48 mV, was optimal for enhancing functional properties of the emulsion. The US-9 emulsion exhibited different surface rheological properties compared to other emulsions, revealing a heterogeneous MFGM stabilization interface predominantly made of MFGM fragments, free phospholipids, and proteins. The US-9 emulsion surface covered more phospholipids, indicating improved emulsion persistence, based on interfacial protein and phospholipid content calculations and microstructure observation. While the US-9 emulsion did not affect fat digestion, the US-6 min treatment resulted in an optimal fatty acid release rate. Further experimentation may be necessary to elucidate the intricate relationship between ultrasound duration and fat digestion. These findings have leaded to a better understanding of the emulsification capabilities of MFGM materials, as well as a foundation to improve infant formula quality. • Ultrasound modifies proteins could alter their structures. • Ultrasound can influence the composition of the droplet interface. • The physicochemical properties of the emulsion after ultrasound have improved. [ABSTRACT FROM AUTHOR]

This work investigated the effect of treatment of soy protein isolate (SPI) with basic amino acids (BAA) (l -Arginine, l -Histidine, and l -Lysine) at different concentrations prior to spray drying on the beany-flavor and functional properties. The results illustrated that the BAA prominently improved the solubility and emulsifying properties of SPI, and reduced the its release of beany-flavor compounds. Additionally, l -Arginine was more effective in increasing the solubility and emulsifying properties of the SPI than l -Histidine and l -Lysine. Notably, 0.3% l -Arginine improved the solubility, emulsifying activity index, emulsifying stability index of the SPI by 43.5%, 64.2% and 45.3% respectively. Through the headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), the 0.3% BAA showed the better mitigation effect on the beany flavor of SPI among three addition concentrations. The increased ζ-potential showed that BAA enhanced the electrostatic repulsion of the SPI, facilitating its dissolution and formation of a more stable emulsion system. Surface hydrophobicity and fluorescence spectral results revealed that BAA enhance the exposure of hydrophobic groups, enhancing the stability of oil-water interface and promoting the interaction between beany-flavor compounds and SPI. These findings lay the theoretical groundwork for further research and application of soy protein. [Display omitted] • Basic amino acids (BAA) increased the solubility of soy protein isolate (SPI). • BAA enhanced the emulsion activity/stability index of SPI. • BAA diminished the release intensity of beany flavor from SPI. • BAA improved the absolute value of potential and surface hydrophobicity of SPI. • BAA reduced the free sulfhydryl groups of SPI. [ABSTRACT FROM AUTHOR]

The quality and safety of Pu-erh tea are largely determined by microorganisms, processing and storage conditions. The systemic co-relationship between microbiome and metabolomics during manufacturing of Pu-erh tea is not fully clarified. We comprehensively explored the microbial and metabolic dynamic evolution and revealed the decisive factors for the quality and safety of Pu-erh tea based on creative methods. The results showed that fungal abundance increased in the middle of pile fermentation period and then decreased during storage, but the bacterial abundance increased in the initial stage, subsequently decreased and finally increased. All microorganism species as well as dominant fungi and bacteria were identified during different processing steps. A total of 209 metabolites were identified and 50 of them were characterized as critical metabolites responsible for metabolic changes. Multivariate analysis verified that these critical metabolites were generated by specific dominant species. The environmental condition exhibited a great effect on the growth and reproduction of bacteria, but less than 10% of the dominant fungi exhibited significant correlation with temperature and humidity. In conclusion, our results revealed the microbial composition is the critical factor in changing the metabolic profile and provided a theoretical basis for improving the quality and safety of Pu-erh tea. • We explored the correlation between microbiome and metabolomics of Pu-erh tea. • Creative methods were used to clarify microbial and metabolic dynamic evolution. • The environmental condition affected the growth and reproduction of microorganism. • This study revealed the decisive factors for the quality and safety of Pu-erh tea. [ABSTRACT FROM AUTHOR]

It is unclear whether biofilm production by co-cultured lactic acid bacteria (LAB) reflects symbiosis among the strains or simply storage stability. This study pairwise combinations of Streptococcus thermophilus ST0 and four strains of lactobacilli to measure the growth relationship and the biofilm yield. The results showed that, during co-culture, the four lactobacilli strains promoted the growth of S. thermophilus ST0 (P < 0.05), and that S. thermophilus ST0 promoted the growth of Lactobacillus delbrueckii subsp. Bulgaricus LD1 and Lactobacillus helveticus LH3 (P < 0.05), but inhibited the growth of Lactobacillus kefiranofaciens LK2 (P < 0.05), and exerted no obvious effect on the growth of Lactobacillus paracasei LP4 compared with strain alone. In terms of the amount of biofilm formed, significantly more was produced by mixed species during the co-cultivation process than by a single strain (P < 0.05), regardless of whether there was a symbiotic relationship among the strains, indicating that biofilm formation by co-cultured strains is not necessarily related to symbiosis among the strains. During the storage of milk fermented by strains co-cultured at 4 °C, the biofilm was inhibited and viable cell numbers were greatly reduced. Biofilm formation slowed the decline in viable cell numbers (P < 0.05). • Biofilm yield of mixed strains was higher than the single when they were co-cultured. • There was no correlation between biofilm yield and symbiosis of co-cultured strains. • LAB biofilm can resist acidic and maintain the storage stability of fermented milk. [ABSTRACT FROM AUTHOR]

Food grade titanium dioxide (TiO 2) usually contains a nanosized fraction, while only a few studies had investigated the effects of TiO 2 nanoparticles (NPs) on the other food components via oral exposure. This work investigated the impact of TiO 2 NPs on the content, bioaccessibility and antioxidant activity of polyphenols in the apple juice. Results indicated that adding 500 mg/100 g TiO 2 NPs significantly decreased the contents of total polyphenol and the main individual polyphenols in the apple juice, which was attributed to the formation of polyphenol-TiO 2 NPs charge transfer complexes aggregation. Additionally, the addition of TiO 2 NPs reduced the bioaccessibility and antioxidant activity of apple polyphenols in a dose dependent manner. This study indicated that TiO 2 NPs can bind polyphenols in the complex food matrix, and provided valuable insights into the influence of food grade TiO 2 NPs on the other food components after oral consumption. [Display omitted] • Effect of TiO 2 NPs on the bioaccessibility and antioxidant activity of apple polyphenol was studied. • TiO 2 NPs can bind with polyphenols in the complex food matrix. • TiO 2 NPs reduced the contents of total and individual apple polyphenols in a dose-dependent manner. • The formation of polyphenol-TiO 2 NPs complexes reduced the antioxidant activity of apple juice. [ABSTRACT FROM AUTHOR]

To improve the pungent flavor quality of soilless cultivated Chinese chives (Allium tuberosum Rottler), the effect of foliar spraying with methyl jasmonate (MeJA) was studied. Electronic nose analysis showed that 500 μM MeJA significantly promoted the accumulation of aromatic compounds and organic sulfides in soilless-cultivated Chinese chives, as well as the content of pungent flavor metabolites, such as enzymatic pyruvic acid (24.9%–69.9%) and the garlic odor compounds alliin (22.1%–51.4%) and methionine (8.0%–62.7%). Using the HS-SPME-GC-MS technique, fifteen species of 186 volatile metabolites were detected in Chinese chive leaves treated with MeJA, and the sulfur compounds were dominating between them (49.6%–61.7%). Metabolomics and chemometrics analysis identified the volatile biomarkers of MeJA-treated substrate culture and hydroponic Chinese chives as dimethyl disulfide, dimethyl tetrasulfide, diallyl disulphide and allyl methyl sulfide, and methyl 2- propenyl disulfide, dimethyl tetrasulfide compound, respectively. Orthogonal partial least squares discriminant analysis indicated that MeJA treatment enhanced the pungency of Allium tuberosum mainly by increasing the accumulation of dimethyl sulfide and allyl sulfide compounds. Current study provides theoretical and technical basis for improving the pungent flavor quality of soilless-cultivated Chinese chives. • E-nose analysis confirmed that MeJA promoted an increase sulfide (1.8%). • MeJA enhanced pungent flavor of Chinese chives (47.4%). • MeJA enhanced garlic odor compounds alliin (36.8%) and methionine (35.4%). • Dimethyl and allyl sulfide as biomarkers of pungent in substrate-grown Chinese chive. • Dimethyl sulfide as a biomarker of pungent in hydroponic Chinese chive. [ABSTRACT FROM AUTHOR]

Pyracantha fortuneana (Maxim.) Li fruits (PFFs) are a traditional food with multiple health benefits. Considering the limited information about how drying methods affect chemical and functional properties, this study aimed to determine the effects of hot-air drying (HAD), far-infrared drying (FIRD), vacuum drying (VD), freeze drying (FD), and sun drying (SD) on the appearance, microstructure, and chemical and functional properties of PFFs. Results showed that the qualities changed considerably with different methods. FD fruits had comparable chemicals (phenolics and flavonoids) and bioactivities (antioxidant activities and digestive enzyme-inhibitory effects) to fresh samples. SD and HAD at 40 °C did not trigger serious degradation of bioactivities. Conversely, higher temperatures (60 °C and 80 °C) resulted in remarkable shrinkage and microstructure damage. HAD60, FIRD60, VD60, and HAD80 decreased the contents of free phenolics (by 59.6%, 58.4%, 56.0%, and 61.0%, respectively, P < 0.05) and flavonoids (by 41.8%, 39.8%, 34.7%, and 48.5%, respectively, P < 0.05) compared with the contents in fresh samples. Heat treatment also reduced bioactivities. Principal component and clustering analyses revealed the relationship between samples and properties, indicating that FD, HAD40, and SD preserved chemicals and bioactivities. Generally, the results suggested that the suitable drying technique for PFFs was low-temperature drying. [Display omitted] • The effects of seven drying methods on P. fortuneana fruits were compared. • Drying temperature and technique significantly impacted the quality of the fruits. • Freeze drying had the least impact on the appearance and chemical and functional properties. • HAD80 reduced the antioxidant activity and digestive enzyme inhibition. • A low temperature effectively preserved the chemical composition and bioactivities. [ABSTRACT FROM AUTHOR]

Chlorogenic acid (CA), a natural polyphenolic antioxidant, is used in meat products to prevent spoilage due to oxidation. Transglutaminase (TGase) is an effective protein cross-linking agent applied to meat gel products to increase the elasticity of the protein gel. The present study illustrated the effect of CA at various additions (5, 20, and 100 μmol/g protein) and/or TGase (0.2 g/100g protein) on physicochemical and gel characteristics of myofibrillar protein (MP). Texture and rheological results demonstrated that the TGase improved the gel structures of oxidized MP treated with CA (5 and 20 μmol/g protein). Scanning electron microscope (SEM) result showed that TGase addition made the gel network orderly, and overcame the phenomenon induced by excessive aggregation of proteins by CA at a high dose (100 μmol/g protein). In addition, water-holding capability (WHC) and low-field NMR (LF-NMR) results demonstrated that the TGase dramatically enhanced the water-holding capability of oxidized MP gel treated with CA (P < 0.05), and the moisture distribution became uniform. FT-IR analysis showed that reduced α-helix structure contributed to improving gel properties. SDS-PAGE indicated that TGase enhanced cross-linking of proteins. Conclusionally, TGase improved the physicochemical and gel properties of CA-modified oxidized myofibrillar proteins. [Display omitted] • CA greatly reduced carbonyls formed by MP oxidation. • TGase ameliorated the gel deterioration caused by a high dose of CA. • CA and TGase enhanced the texture of meat gel products. • Delaying oxidation and promoting crosslinking improved MP gel properties. [ABSTRACT FROM AUTHOR]

Interfacial deformation and interfacial rheology behaviour of prolamin particles are relevant factors affecting their emulsification performance but have not yet been paid considerable attention to. Based on the finding that CMC modification significantly improved the emulsifying property of gliadin colloid particles (GCPs), the present study combined in situ observation and interfacial rheology as a tool to investigate the effect of CMC on the structure characteristics, interfacial deformation and interfacial rheology behaviour of GCPs and their correlation with emulsifying performance. The results demonstrated that gliadin/CMC complex particles (GCCPs) presented looser core-shell structures than GCPs. The interfacial deformation of particles and the formation of smooth interfaces were observed for both GCPs and GCCPs, and GCCPs exhibited faster deformation behaviour, which should correlate to the looser structure. Although GCCPs showed lower surface pressure and viscoelasticity modulus, the existence of CMC promoted the initial adsorption of particles and accelerated the formation of viscoelastic interfacial films, which contributed to the improvement of emulsifying performance. In addition, CMC endowed the interfacial layers with moderate viscosity and fluidity to resist the destabilisation induced by oil droplet deformation. The present study should provide insights for intuitive understanding and fine regulation of the interfacial behaviour of protein particles. • Gliadin/CMC complex particles present a relatively "softer" core-shell structure. • "Softer" structure is easier to unfold and deform at the oil-water interface. • Faster interfacial deformation of particles benefits the emulsifying performance. • CMC promotes the initial adsorption and accelerates the formation of interface layers. • Moderate interfacial viscosity and fluidity facilitates the stability of oil droplets. [ABSTRACT FROM AUTHOR]

This research presents the physicochemical property of the mixtures induced by blending konjac glucomannan (KGM) and welan gum (WL). The effects of the ratio and concentration on the rheological properties of the KGM and WL mixtures, such as shear rate and strain (large-amplitude oscillatory shear, frequency, temperature, time, stress relaxation, and creep), were studied. The combination analysis of Fourier transform infrared spectroscopy, scanning electron microscopy, thermodynamic differential scanning calorimetry, water mobility, and distribution property analyses through low-field nuclear magnetic resonance spectroscopy were used to determine the authenticity of gels. Finally, a model of the interaction force was constructed to elucidate the interaction mechanism when heating. The result showed that the mixtures of KGM and WL were pseudogel. The synergy effect was positively correlated with concentration, which was the strongest when the KGM (g/kg): WL (g/kg) ratio was 2:8. Abnormal temperature sensitivity (sudden drop of modulus around 30 °C) was observed at the ratio, and the mixture owned good temperature reversibility in 3 cycles. This work expanded the application scope of KGM and WL and provides a method for the determination of gels. • Strong synergistic interaction occurred between the Konjac glucomannan and Welan gum. • Abnormal temperature-sensitive phenomenon appeared for the mixture at a certain radio. • Abnormal phase separation during heating was caused by physical interaction. • Different characterization methods were combined to determine the pseudo-gel accurately. [ABSTRACT FROM AUTHOR]

Stable O/W Pickering emulsions synergistically stabilized by heat-induced soy protein isolate (HSPI) and bacterial cellulose nanofibrils (BCNFs) were fabricated, and spray-dried to obtain edible oil powders. The emulsions with 0.2 wt% BCNFs and 2 wt% HSPI displayed homogeneous droplets size (<1 μm) and narrow size distributions, and had no obvious droplet aggregates at different oil phase ratios (10–20%) with 2 wt% beeswax. After spray drying, the obtained stable oil powders (35.9–56.8%) presented hollow smooth spherical structure with small and uniform size. The moisture content, flowability, bulk density and encapsulation efficiency of oil powders were improved by tuning the BCNFs contents and oil-to-water ratios of emulsions. Furthermore, the presence of BCNFs partially inhibited lipid hydrolysis, and oil powders with 0.1 wt% BCNFs performed optimum anti-digestibility with the minimum released FFA values of 72.5%. This work combined spray drying technique with Pickering emulsions for oil encapsulation, and optimized the emulsions properties to address the limitations of spray drying for liquid oil microencapsulation, which would provide some guidance for oil powders development. • Stable O/W Pickering emulsion stabilized by HSPI/BCNFs complexes was fabricated. • Edible soybean oil powders were successfully prepared after spray drying. • Oil powders with 10% soybean oil had relatively low SO and high EE values. • Oil powders with BCNFs had improved physical properties and anti-digestibility. [ABSTRACT FROM AUTHOR]

Application of Monascus pigments in the food industry is hindered by their vulnerability to light, yet the underlying mechanism of their light-induced fading remains unclear. In this study, Monascus pigments sourced from Monascus rice were employed to investigate their stability under distinct light treatments, including visible light, UV light, and sunlight. The research demonstrates a clear connection between the light stability of Monascus pigments and their composition. Among the various light sources, simulated sunlight emerges as the most deleterious to the red Monascus pigment, whereas UV light inflicts greater damage on the yellow Monascus pigment compared to other sources. Employing density functional theory (DFT) and time dependent DFT (TDDFT), we deduced the mechanism of Monascus pigments' photolysis by comparing E HOMO , E LUMO , △E, λ max , and E λmax of the six original Monascus pigments. The outcomes reveal a distinct photo-stability sequence for different pigments: red Monascus pigment < orange Monascus pigment < yellow Monascus pigment. Furthermore, our study proposes electron transfer from the c = c double bond to the c-c single bond as a component of the photolysis mechanism. This research contributes theoretical and experimental evidence on the photo-stability and mechanisms governing diverse Monascus pigments under various light conditions. These insights are crucial for optimizing the integration of these pigments in the food industry, with implications for packaging and storage considerations. • The impact of various lights on the stability of Monascus pigments was explored. • A relation between Monascus pigments' light stability and their composition was identified. • The electron transfer during the Monascus pigment photo-degradation was elucidated. [ABSTRACT FROM AUTHOR]

To solve the problem of apple powder strong hygroscopicity, wheat gluten was selected as a natural anticaking agent and added into apple powder in different proportions. The moisture absorption data of the samples was monitored in different relative humidity environments at 25 °C and 35 °C. The results showed that the addition of wheat gluten could reduce the equilibrium moisture content and the size and number of agglomerates of freeze-dried apple powder. The fitting parameters of the Guggenheim-Anderson-DeBoer and the low-field nuclear magnetic resonance results revealed that the existence of wheat gluten restricted the water migration, which was conducive to maintain a good particle state of powder. To sum up, the wheat gluten as an anticaking agent could not only have the effect of inhibiting moisture absorption during the storage of freeze-dried apple powder, but also possess the potential to be used in various fruit powder production. [Display omitted] • The apple powder was prepared by the method of freeze-drying. • Wheat gluten reduced equilibrium moisture content and agglomerates of apple powder. • Wheat gluten changed the moisture absorption isotherms type of apple powder. • The existence of wheat gluten restricted the water migration of apple powder. [ABSTRACT FROM AUTHOR]

Several studies have shown that microorganisms are key factors in the transformation of dark tea chemicals. However, these studies have mainly used relative abundance to study the diversity of the microbial community during tea fermentation. The dynamics of microbial density and assembly of abundant and rare microbes remains poorly understood. In this study, the entire manufacturing process of Qingzhuan brick tea (QBT) was studied at an industrial scale. The succession of both bacterial and fungal communities was investigated using high-throughput sequencing along with quantitative PCR (qPCR) analysis. Changes in non-volatile flavor components, including soluble sugar (SS), total polyphenols (TP), nine tea catechins, caffeine, 21 free amino acids, and three tea pigments were detected. Mantel test showed that both bacterial and fungal community structures were significantly correlated with environmental variables during the microbial fermentation process but not during the aging process. The absolute microbial density was calculated based on qPCR gene copies and relative abundance. The quantitative microbiota network showed that dominant microbes constitute the basic skeleton of the network, while rare microbes have a stronger correlation with various flavor contents. These results help to understand the assembly of microbial communities and their role in the formation of tea flavor substances. • Microbes affect the flavor of fermented QBT during the microbial fermentation process but not during the aging process. • The content of GA, CAF, and GABA increased during the manufacturing process. • Bacterial community showed a stronger correlation with the global environmental variables than the fungal community. • Dominant microbes constitute the basic skeleton of the network. • Rare microbes showed strong correlation with various flavor contents. [ABSTRACT FROM AUTHOR]

Pickering emulsions stabilized by biopolymers have been gaining increasing attention in recent years. In this work, chitosan/guar gum (CS/GG) nanoparticles were formed by hydrogen bond interactions between amino of CS and hydroxyl of GG. The surface charge and aggregation degree of CS/GG nanoparticles could be regulated by pH value to yield Pickering emulsion of superior quality. Emulsions had optimal physical stability at pH 6.0 and oil fraction of 0.6, with the lowest creaming index of 1.81 ± 0.21% after six months of storage at 4 °C. Contents of primary and secondary oxidation products stored at 37 °C for 30 days in Tween 80-stabilized emulsion are almost 1.46 and 1.66 times that of CS/GG-stabilized Pickering emulsion. These results indicated that CS/GG-stabilized Pickering emulsion had better lipid oxidation stability than Tween 80-stabilized emulsion. In addition, the retention rate of astaxanthin of CS/GG-stabilized astaxanthin Pickering emulsion (85.9 ± 0.57%) was higher than Tween 80-stabilized astaxanthin emulsion (66.12 ± 0.71%) stored at 37 °C for 30 days. This result indicated that the stability of CS/GG-stabilized astaxanthin-loaded Pickering emulsion was better than Tween 80-astaxanthin emulsion. This study provides a framework for applying Pickering emulsions formed using polysaccharide particles in functional foods. [Display omitted] • CS/GG complex nanoparticles were obtained as Pickering stabilizers. • Aggregation degree and size of CS/GG nanoparticles could be regulated by pH value. • CS/GG Pickering emulsion had better stability than Tween 80-based emulsion. • CS/GG Pickering emulsions encapsulated and stabilized astaxanthin effectively. [ABSTRACT FROM AUTHOR]

Taihe silky chicken (TSC) has been consumed as a specialty food in China for over 2200 years. In this study, LC/MS-based lipidomics and GC/MS-based volatilomics were used to compare lipids and volatile compounds of Cobb chicken (CC) and TSC to investigate the differences in meat quality between them. TSC showed higher intramuscular fat content, linoleic acid (C18:2), arachidonic acid (C20:4), and dococsahexaenoic acid (C22:6, DHA) (p < 0.05). Lipidomic analysis revealed significant differences between CC and TSC lipids at class and molecular levels. We found that 106 and 69 lipid molecules could be used as potential biomarkers to distinguish TSC in positive and negative modes, respectively. The volatile compounds in CC and TSC were clearly different. We screened 24 volatiles that can be used as potential biomarkers. Our study revealed exhaustive TSC profiles of lipidomic and volatilomic and can help to distinguish and evaluate Chinese black-bone chicken. • Lipidomics and volatilomics profiling of Cobb chicken (CC) and Taihe black-boned silky chicken (TSC) was performed. • Volatilomic profiles from Chinese black-bone chicken were characterized by Q Exactive GC-Orbitrap-MS. • Two kinds of chicken were distinguished based on 53 volatiles identified. • The potential lipid and volatile markers for chicken discrimination were identified. [ABSTRACT FROM AUTHOR]

Amino acids are often used as growth factors to promote the growth of strains, but we found that adding aspartic acid to the medium could significantly improve the freeze-drying survival rate of some Lactobacillus plantarum (p < 0.05). Our research aimed at Lactobacillus plantarum LIP-1, after exploring its internal mechanism, it is proved that the addition of aspartic acid could significantly reduce the strain's cell wall, cell membrane and DNA damage during the freeze-drying process. Further research concluded some critical points after adding aspartic acid into a medium as below: reduce cell wall damage by increasing the peptidoglycan content, protect the integrity of the cell membrane by increasing the content of long-chain fatty acids, unsaturated fatty acids and cyclopropane fatty acids in cell membranes, and reduce DNA damage by increasing the intracellular pH. Further studies are needed on improving the freeze-drying survival of strains by altering the composition of culture media. • Aspartic acid could improve survival rate of strain during freeze-drying. • Aspartic acid reduced the damage of strain during freeze drying process. • Aspartic acid could increase the peptidoglycan content in the cell wall. • Aspartic acid could adjust fatty acid composition of the cell membrane. • Aspartic acid reduced DNA damage by increasing intracellular pH. [ABSTRACT FROM AUTHOR]

Meat analogues, a kind of healthy promising meat substitute, are gaining more and more attention due to its eco-friendly, personal satisfactory and low cost benefits. In this study, Haematococcus pluvialis residue (HPR) was used for preparing pea protein-based meat analogues by high moisture extrusion. Mixed raw material with HPR contents ranging from 10 g/100g to 40 g/100g can successfully be extruded under high moisture of 50 g/100g. The reddish color of HPR made the extrudates look like dried red meat. HPR could markedly improve the textural properties by loosening the layered and the fibrous structures of meat analogues. The fibrous degree of meat analogues with 10 g/100g (dry basis) HPR content reached the maximum (1.28 ± 0.05). Even though the HPR content increased to 40 g/100g (dry basis), the fibrous degree of meat analogues was 1.15 ± 0.03, which was higher than the extrudates without HPR (1.08 ± 0.05). The mechanism of forming meat analogues with better texture was mainly caused by the increased free water content and β-Sheet structure of extrudates after adding HPR. On the whole, HPR can be used as a raw material for high moisture extrusion to enhance the physical properties of meat analogues. • Haematococcus pluvialis residue (HPR) can be applied to produce meat analogues. • The best fibrous degree of meat analogues was obtained with 10 g/100g HPR. • The band of β-sheet structure shifted to blue wavelength with the addition of HPR. • This is the first report of high moisture extrusion with microalgae residue. [ABSTRACT FROM AUTHOR]

The thermal stability of the κ-carrageenan/konjac gum (KC/KGM) mixed gel during heating treatment (at 85 °C for 30 min) does not satisfy the demand of the practical application. To solve this problem, gellan gum (GG) or/and Ca2+ were introduced in the κ-carrageenan/konjac gum (KC/KGM) mixed system to enhance mechanical and thermal properties. The effect of GG and Ca2+ on the gel matrix properties was studied by two deformation test (TDT), rheological measurement, scanning electron microscopy (SEM), combined with visual observation. The results showed that neither GG nor Ca2+ alone could reduce the deterioration of the mechanical properties of the KC/KGM gel after heat treatment (at 85 °C for 30 min). Only the participation of GG and Ca2+ could ensure the consistent mechanical properties of the mixed gel before and after heating. The rheological and micro-rheological analysis confirmed that the KC/KGM gel with GG and Ca2+ could always remain solid-state without gel-sol transition under heat treatment. In addition, the thermo-irreversible gels with different texture properties were prepared by adjusting the mass ratio of KC and KGM. Hence, this study may enrich the design of novel gel-based food ingredients. • Either Ca2+ or GG raised the Tgs and Tsg of KC/KGM gels. • An amount of Ca2+ and GG transformed KC/KGM gels into thermo-irreversible gels. • The mass ratio of KC and KGM influenced the texture of thermo-irreversible gels. • This study provided a gel food ingredient with heat resistant treatment. [ABSTRACT FROM AUTHOR]