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Excessive lipid intake is related to the increasing risk of several human chronic diseases. Simple lipid reduction leads to poor taste of food, which cannot be accepted by consumers. Rational design of food O/W emulsion structure to inhibit lipid digestion is considered to be an effective way to maintain diet healthy without reducing sensory quality. Proteins are amphiphilic and polysaccharides have unique rheological properties, which play key roles in the formation and stability of multiphase systems. Recent years, global scholars intend to rationally design protein-polysaccharide multi-scale composite interfaces to improve the functional properties and inhibit lipid digestion of emulsions. In this article, we review the published papers on the effect of protein-polysaccharide multi-scale composite interface on lipid digestibility of emulsion during 2015–2021. The inhibition of protein-polysaccharide based emulsion gel interface on lipid digestion of emulsion is extensively provided. However, the effects of protein-polysaccharide multilayer interfaces, protein-polysaccharide particle interfaces and protein-polysaccharide covalent interfaces on the lipid digestion of emulsion are controversial. Further analysis of the published papers found that the ability of the protein-polysaccharide multi-scale composite interfaces to maintain their structural integrity is the key factor affecting lipid digestion of the emulsions. The ability of the oil-water interfaces to maintain its structural integrity in the small intestine is regulated by its interfacial structure. Thus, revealing the regulatory mechanism of the interfacial structure of the emulsions on its structural changes and lipid digestion in the digestive tract is the basis and key to resolve the above controversy. Therefore, further systematic research is needed to fulfill the theoretical system of the rational design of emulsion structure on its lipid digestibility. • Protein-polysaccharide based emulsion gel interface could inhibit lipid digestion. • Effects of protein-polysaccharide multilayer interfaces, particle interfaces and covalent interfaces on the lipid digestion of emulsion are controversial. • The controversy limits the rational design of emulsion structure to control its lipid digestion. • Revealing the regulatory mechanism of the interfacial structure of the emulsions on lipid digestion is the key to resolve the controversy. [ABSTRACT FROM AUTHOR]

Abstract In this article, oil-in-water (O/W) emulsions stabilized by natural whey protein concentrate (WPC) and microparticulated whey protein (MWP) and their mixtures with xanthan gum (XG) were prepared to investigate the lipid oxidative stability of O/W emulsions with the same interfacial composition but different interfacial structures. High-performance size exclusion chromatography, Fourier transform infrared spectrometry, X-ray diffraction analysis and steady-state fluorescence spectroscopy were used to reveal the differences in the structures of natural whey protein and the microparticulated whey proteins (MWP, pH 3.5–8.5). Dispersions of the proteins (70% w/w) and XG (30% w/w) were mixed to prepare the mixtures (protein-XG). Emulsions of 60% peanut oil that were stabilized by the proteins and the protein-XG mixtures were subjected to oxidation. In addition, the peroxide values (PVs) were measured to evaluate the oxidative stability of each emulsion. The MWP(pH 4.5)-XG and MWP(pH 6.5)-XG-stabilized emulsions showed high oxidative stabilities that were not significantly different from each other. The results indicated that a single complex layer formed by the spherical protein microparticles and XG can better inhibit the lipid oxidation of O/W emulsions than a double layer. This study has significant implications for the development of novel structures containing lipid phases that are susceptible to oxidation. Graphical abstract Unlabelled Image Highlights • The interfacial structure with same interfacial composition affected the emulsion oxidative stability. • XG addition inhibited the oxidation rate of protein-stabilized emulsions. • Single complex layers formed by spherical protein microparticles-XG inhibit the emulsion lipid oxidation. [ABSTRACT FROM AUTHOR]

This article reports caloric value changes, stability and rheological properties of mayonnaises affected by fat mimetic based on Microparticulated whey protein (MWP) and high-methoxy pectin. Lipid was partially substituted at different levels of 20%, 40%, 60%, 80% and 100%, and the samples were referred to as FM20, FM40, FM60, FM80 and FFM, respectively. The full fat (FF) mayonnaise was used as a control experiment. For rheological properties, the addition of fat mimetic resulted in the gradual decrease of pseudoplastic behavior, relative thixotropic area and viscosity index, while elasticity index exhibited the opposite trend. After 30 days of storage, all mayonnaises except FM20 were categorized as weak gels under oscillatory tests, while FM20 displayed high storage stability. Long-term stability studies showed that the addition of the fat mimetic up to 60% could significantly enhance the storage stability of mayonnaises by preventing the coalescence and flocculation of the droplets. Both the dynamic mechanical measurement and stability study results suggested that MWP and pectin could be a potential fat mimetic used in mayonnaise. [ABSTRACT FROM AUTHOR]

• New insight for application of SA and its derivatives on storage of fruit and vegetable. • Treatment of SA and derivatives include dipping, coating, fumigating and spraying. • SA and derivatives improve storage quality by inhibiting fruit senescence and CI. • SA and derivatives enhance antioxidant capacity, fruit flavor and pathogen resistance. The applications of salicylic acid (SA) and its derivatives including acetylsalicylate (ASA) and methyl salicylate (MeSA) have been widely used to preserve fruit and vegetables. This paper reviewed recent researches on preharvest and postharvest treatment methods of SA and its derivatives and summaried the effectiveness on postharvest physiological processes of fruit. The preharvest spraying is recommended as the optimal method because of its rapid absorption efficiency of salicylates and the less time of postharvest handing time. Applications of SA and its derivatives have been demonstrated to improve the storage quality by decreasing ethylene production and respiration rate, suppressing fruit softening and color change, keeping the sugars, organic acids and aroma, inhibiting chilling injury, promoting pathogen resistance and activating antioxidant system. The comparison of treatment method and physiological analysis in this review can provide deep insight into practical application of SA and its derivatives on storage of fruit and vegetables. The treatment methods of SA and its derivatives and the effect of maintaining the fruit quality, increasing phenolic compounds and antioxidant capacity, inhibiting biotic and abiotic stresses and keeping the flavor. [Display omitted] [ABSTRACT FROM AUTHOR]

The overall objective of this study was to determine the influence of altering pH on the rheological and gelling properties of whey protein concentrate (WPC) and superfine grinding-treated whey protein concentrate (sWPC). Superfine grinding could produce a narrow and uniform particle size distribution in powders. The rheological and gelling properties of five types of protein powders with mean particles size of 48.0 μm, 27.5 μm, 21.5 μm, 11.9 μm and 8.8 μm were investigated. With the decrease of powder particle size, the lightness, gelling properties and WHC of gels at pH 4.5 were significantly improved. Thus, the operations of superfine grinding rendered WPC into an ingredient with excellent gelling properties at pH 4.5, and which can be of practical utility in production of microparticulted whey proteins. Correspondingly, the longer of superfine grinding processing time, the thinner of gels and higher of gelation temperature (from 73.5 °C to 85.6 °C) at pH 6.5. [ABSTRACT FROM AUTHOR]

Microparticulated proteins (MPPs) considerably improve the texture, taste and nutritional value of low-fat dairy products. A combination of superfine grinding and heat-shearing treatment was utilized in order to improve the processing adaptability and stability of microparticulated whey protein (MWP). Comparing the mean particle sizes of WPC and MWP with the superfine milled whey protein concentrate (sWPC) and its microparticulated whey protein (sMWP), the sWPC and sMWP were significantly decreased from 49.24 and 13.09 μm to 8.17 and 5.73 μm, respectively ( P < 0.05). Both sWPC and sMWP exhibited higher water-holding capacity (1.9 and 3.69 g/g, respectively), emulsion activity index (146.38 and 128.6 m/g, respectively), emulsion stability index (29.04 and 6.31, respectively) and viscoelasticity than WPC and MWP. The dispersion stability of sWPC, sMWP and its cream mimetic were also enhanced after superfine grinding treatment. The sMWP dispersion exhibited more stable liquid behaviour characteristics and maintained the creamy mouth feel better than MWP, indicating the higher dispersion stability of sMWP-based cream mimetic. Therefore, the combined superfine grinding and heat-shearing treatment is a promising technique for the production of microparticulated proteins. [ABSTRACT FROM AUTHOR]

In this study, superfine grinding and microparticulation were employed to increase the hydrophobicity of whey protein concentrate (WPC), which was investigated using 8-anilino-1-naphthalene sulfonic acid. WPC-stabilized emulsions containing 40% and 80% (w/w) oil showed smaller average droplet size when superfine grinding-treated WPC (sWPC) and microparticulated protein (MPP) were used than when WPC was used. The micro-rheology of the emulsions was measured upon diffusing wave spectroscopy; results showed that MPP can form stable emulsions. Moreover, the solid liquid balance of the emulsions significantly decreased from 0.87 to 0.38, with changing states from liquid to solid. The Turbiscan Stability Indexes of sWPC and MPP significantly reduced from 15.23 to 13.58 and 1.17, respectively. The operations of superfine grinding and microparticulation rendered WPC into an ingredient with excellent emulsifying properties. Thus, this ingredient can be utilized in both reduced-fat and high-fat food applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preharvest SA and postharvest 1-MCP treatments can improve the quality of apricot. • Synergistic and antagonistic effects of SA + 1-MCP on apricot were manifested. • SA + 1-MCP treatment showed positive stack of effects on the quality of apricot. • SA counteracted side effects and enhanced positive effects of 1-MCP on apricot. Preharvest salicylic acid (SA, 1 mmol/L) spraying at 72 and 74 days after complete bloom combined with postharvest 1-methylcyclopropene (1-MCP, 1 μL L-1) fumigation was conducted to improve the storage quality of apricot. The results showed that preharvest SA combined with postharvest 1-MCP (SA + 1-MCP) treatment delayed the ethylene peak, inhibited respiration, slowed fruit softening, maintained high sugar and organic acid contents, and maintained high antioxidant capacity in apricots. SA + 1-MCP treatment produced synergistic effects on ethylene production, respiration rate, firmness, sorbitol, glucose and citric acid, but antagonistic effects on fructose, sucrose, malic acid, and total phenolic content and antioxidant capacity. In addition, SA treatment could overcome the disadvantages or enhance positive effects of 1-MCP treatment. Both synergistic and antagonistic effects of SA + 1-MCP treatment can achieve efficient preservation than individual 1-MCP or SA treatment. Thus, the SA + 1-MCP treatment may be an effective method for improving the storage quality of apricots. [ABSTRACT FROM AUTHOR]

Chitosan (CS) and pea protein isolate (PPI) were used as raw materials to prepare nanoparticles. The structures and functional properties of the nanoparticles with three ratios (1:1, 1:2 1:3, CS:PPI) were evaluated. The particle sizes of chitosan–pea protein isolate (CS–PPI) nanoparticles with the ratios of 1:1, 1:2, and 1:3 were 802.95 ± 71.94, 807.10 ± 86.22, and 767.75 ± 110.10 nm, respectively, and there were no significant differences. Through the analysis of turbidity, endogenous fluorescence spectroscopy and Fourier transform infrared spectroscopy, the interaction between CS and PPI was mainly caused by electrostatic mutual attraction and hydrogen bonding. In terms of interface properties, the contact angles of nanoparticles with the ratio of 1:1, 1:2, and 1:3 were 119.2°, 112.3°, and 107.0°, respectively. The emulsifying activity (EAI) of the nanoparticles was related to the proportion of protein. The nanoparticle with the ratio of 1:1 had the highest potential and the best thermal stability. From the observation of their morphology by transmission electron microscopy, it could be seen that the nanoparticles with a ratio of 1:3 were the closest to spherical. This study provides a theoretical basis for the design of CS–PPI nanoparticles and their applications in promoting emulsion stabilization and the delivery of active substances using emulsions. [ABSTRACT FROM AUTHOR]

N-SDF, S-SDF, E-SDF, and SE-SDF were extracted from natural pea dietary fibre (DF) and modified pea DF by superfine grinding (S), enzymatic modification (E), and superfine grinding combined with enzymatic modification (SE). The structures, physicochemical properties, hypoglycaemic functional properties, and antioxidant activities of the three types of modified SDF were compared with those of natural N-SDF. The results showed that the four SDF types had similar infrared spectra and monosaccharide compositions, whereas their main functional groups, binding degree, and monosaccharide content were different. The molecular weights of S-SDF and SE-SDF decreased compared to that of natural N-SDF, whereas that of E-SDF increased. The microstructure of SE-SDF showed the softest, roughest, and most porous morphology compared with those of the other three SDF types. The hypoglycaemic functional properties (glucose adsorption capacity, glucose dialysis retardation index, and α -amylase inhibition rate) of the three modified SDF types were improved compared with the natural N-SDF. Moreover, SE-SDF had the best effect. In addition, the DPPH · scavenging ability, reducing power, and · OH scavenging ability of S-SDF and SE-SDF were improved compared with those of natural N-SDF. Remarkably, all four SDF types exhibited excellent ABTS · scavenging ability at a concentration of 0.6 mg/mL. Consequently, SE-SDF holds promise as an outstanding food additive for reducing postprandial blood glucose levels, enhancing antioxidant activities, and mitigating oxidative damage. The modification mechanism, characterisation, hypoglycaemic, and antioxidant properties of pea dietary fibre modified by superfine grinding (S), enzymatic modification (E), and superfine grinding combined with enzymatic modification (SE). [Display omitted] • Four SDFs had similar infrared spectra and monosaccharide compositions. • S, E, and SE all can enhance the hypoglycaemic functional properties of pea SDF. • The antioxidant activities of SE-SDF were highest than other SDFs. • The hypoglycaemic and antioxidant mechanism was revealed. [ABSTRACT FROM AUTHOR]

• mmol L−1 of MeSA improved the storage quality of cherry at low temperature. • MeSA could reduce the loss of alcohols, aldehydes, ketones and terpenoids of cherry. • MeSA could increase the content of esters of cherry during cold storage. Cherries are easy to soften and rot during the period of storage. This work was performed to assess the impact of different concentrations of methyl salicylate (MeSA, 0.1 mmol·L−1, 1.0 mmol·L−1, 2.0 mmol·L−1) on fruit quality and aroma compounds of cherries ('Meizao' and 'Labins') during cold storage (0 °C). Results showed that 1.0 mmol·L−1 of MeSA had the greatest effect on decreasing the respiration rate, improving the firmness and maintaining the soluble solids content (SSC) of cherry fruits. The main volatile aroma compounds in 'Meizao' and 'Labins' cherries were benzyl alcohol, hexanal, trans-2-hexenal, benzaldehyde and 2-hexenal. Additional observations revealed that MeSA could increase the ester aroma compounds and delay the loss of alcohol, aldehyde, ketone and terpenoid aroma compounds in postharvest cherries. Therefore, MeSA could effectively improve the quality and inhibit aroma loss of cherry fruits during cold storage. [Display omitted] [ABSTRACT FROM AUTHOR]

Emulsion micro-gels exhibit significant potential as functional ingredients for modifying food texture, replacing saturated fats, or serving as templates for the controlled release of bioactive compounds. Structural design principles are being applied more frequently to develop innovative emulsion micro-gels. In this paper, whey protein concentrate (WPC), κ-carrageenan and sodium alginate (SA) were utilized for preparing emulsion micro-gels. To reveal the regulation mechanism of the structural and physicochemical properties of emulsion micro-gels on lipid digestion, the influence of SA additions on the structural, physicochemical properties and in vitro digestion behavior of κ-carrageenan/WPC-based emulsion micro-gel were explored. The FTIR results suggest that the emulsion micro-gels are formed through non-covalent interactions. With the increase of SA addition (from 0.7 g/100 mL to 1.0 g/100 mL), the decreased mean droplet size, the increased hardness, elasticity indexes, and water holding capacity, the reduced the related peak times all indicated that the emulsion micro-gels exhibit enhanced rheological, stability, and mechanical properties. It can be concluded from the microstructure, particle size distribution of the emulsion micro-gels during simulated digestion and free fatty acid release that both κ -carrageenan/WPC-based emulsion micro-gel and κ -carrageenan/WPC/SA-based emulsion micro-gel can inhibit lipid digestion due to the ability to maintain structural stability and hindering the penetration of bile salts and lipase through the hydrogel networks. And the ability is regulated by the binding properties the gel matrix and oil droplets, which determine the structure and physicochemical properties of emulsion micro-gels. The research suggested that the structure of emulsion micro-gels can be modified to produce various lipid digestion profiles. It may be significant for certain practical application in the design of low-fat food and controlled release of bioactive agents. [ABSTRACT FROM AUTHOR]

Using the optimal extraction conditions determined by response surface optimisation, the yield of soluble dietary fibre (SDF) modified by superfine grinding combined with enzymatic modification (SE-SDF) was significantly increased from 4.45 % ± 0.21 % (natural pea dietary fibre) to 16.24 % ± 0.09 %. To further analyse the modification mechanism, the effects of three modification methods–superfine grinding (S), enzymatic modification (E), and superfine grinding combined with enzymatic modification (SE)–on the structural, physicochemical, and functional properties of pea SDF were studied. Nuclear magnetic resonance spectroscopy results showed that all four SDFs had α- and β-glycosidic bonds. Fourier transform infrared spectroscopy and X-ray diffraction spectroscopy results showed that the crystal structure of SE-SDF was most severely damaged. The Congo red experimental results showed that none of the four SDFs had a triple-helical structure. Scanning electron microscopy showed that SE-SDF had a looser structure and an obvious honeycomb structure than other SDFs. Thermogravimetric analysis, particle size, and zeta potential results showed that SE-SDF had the highest thermal stability, smallest particle size, and excellent solution stability compared with the other samples. The hydration properties showed that SE-SDF had the best water solubility capacity and water-holding capacity. All three modification methods (S, E, and SE) enhanced the sodium cholate adsorption capacity, cholesterol adsorption capacity, cation exchange capacity, and nitrite ion adsorption capacity of pea SDF. Among them, the SE modification had the greatest effect. This study showed that superfine grinding combined with enzymatic modification can effectively improve the SDF content and the physicochemical and functional properties of pea dietary fibre, which gives pea dietary fibre great application potential in functional foods. The proposed mechanism and characterisation of the modification of pea dietary fibre by superfine grinding (S), enzymatic modification (E), and superfine grinding combined with enzymatic modification (SE). [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Soil salinity is a primary factor limiting soybean (Glycine max) productivity. Breeding soybean for tolerance to high salt conditions is therefore critical for increasing yield. To explore the molecular mechanism of soybean responses to salt stress, we performed a comparative transcriptome time-series analysis of root samples collected from two soybean cultivars with contrasting salt sensitivity. Results: The salt-tolerant cultivar 'Qi Huang No.34' (QH34) showed more differential expression of genes than the salt-sensitive cultivar 'Dong Nong No.50' (DN50). We identified 17,477 genes responsive to salt stress, of which 6644 exhibited distinct expression differences between the two soybean cultivars. We constructed the corresponding co-expression network and performed Gene Ontology term and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. The results suggested that phytohormone signaling, oxidoreduction, phenylpropanoid biosynthesis, the mitogen-activated protein kinase pathway and ribosome metabolism may play crucial roles in response to salt stress. Conclusions: Our comparative analysis offers a comprehensive understanding of the genes involved in responding to salt stress and maintaining cell homeostasis in soybean. The regulatory gene networks constructed here also provide valuable molecular resources for future functional studies and breeding of soybean with improved tolerance to salinity. [ABSTRACT FROM AUTHOR]

Sweet cherry (Prunus avium L.), one of the most appreciated and most important commercial temperate fruits, has high sensory quality and nutritional value. Investigating its metabolic variations provides valuable information on the formation of fruit quality. In this study, widely targeted LC-MS/MS based metabolomics was used to identify and quantify metabolic changes during 'Black Pearl' sweet cherry development and ripening. A total of 263 significant differentially expressed metabolites (DEMs) were detected during the four fruit-development stages. Significant differences were observed in the composition and content of compounds in the four stages of cherry development, especially sugars, organic acids, and flavonoids. Moreover, transcriptome analysis provided a molecular basis for metabolic variations during fruit development. A total of 6724 significant differentially expressed genes (DEGs) were identified. Further correlation analysis of major DEMs and DEGs showed that 19 key DEGs were involved in sugar metabolism, 23 key DEGs in organic acid metabolism, and 13 key DEGs in flavonoid metabolism. The upregulated genes involved in the flavonoid pathway probably play an important role in regulating the rapid increase of anthocyanin content during fruit development. These comprehensive analysis data provide a better understanding to improve fruit quality traits based on molecular and metabolic levels. [ABSTRACT FROM AUTHOR]

The effects of various physical state lipids (rapeseed oil (RO), shortening (ST), beeswax (BW)), on the physicochemical properties of starch (S) (hydroxypropyl distarch phosphate (HP), oxidized hydroxypropyl starch (OS))/gelatin (G) blown films were studied. S/G-lipid blends showed decreased storage modulus and complex viscosity. The formation of hydrogen bonds was inhibited by the ST and BW, but facilitated by the RO. Compared with BW and ST, RO was more effective to promote the melted and fractured of starch. Lipids addition promoted the compatibility of starch and gelatin. The presence of the lipids significantly improved the surface hydrophobicity, mechanical, water vapor barrier and water resistance properties of S/G films. S/G-RO films exhibited the strongest surface hydrophobicity and tensile strength, while HP/G-BW film showed the strongest water resistance and water vapor barrier properties. These results revealed that the appropriate lipids could be used to produce S/G-lipid films with desirable physicochemical properties. • Effects of different physical state lipids on blown S/G films were studied. • Lipids addition facilitated the compatibility of starch and gelatin. • The TS and EAB of films simultaneously increased in the presence of lipids. • HP/G film with the addition of RO formed a hydrophobic film surface. [ABSTRACT FROM AUTHOR]

Fruits and vegetables are highly susceptible to spoilage, and effective postharvest packaging technology can significantly extend their shelf life of fruits and vegetables. Many studies have shown that the use of electrospinning to encapsulate natural bioactive compounds, including plant extracts, metals, and metal oxides, in active packaging can effectively extend the shelf life of postharvest fruits and vegetables. Electrospun films have the characteristics of a large specific surface area, high porosity, and non-thermal processing, which can effectively improve the encapsulation efficiency and slow-release performance of bioactive compounds. This paper reviews the research progress in electrospinning technology encapsulating natural bioactive compounds for postharvest packaging of fruits and vegetables, and the effect of functional electrospun submicro-fiber films on the postharvest storage quality of fruits and vegetables. Encapsulation of natural bioactive compounds into electrospun submicro-fibers film can improve the function of film, including antibacterial property, antioxidant property and ethylene absorption property. These effects include (1) control of softening, (2) inhibition of fruit browning and enhancement of antioxidant capacity, (3) ethylene degradation, (4) reduction of corruption, and (5) regulation of sugars and acids. This review provides deep insights into the current limitations and future prospects of electrospinning technology in the field of active fruit packaging. • Natural bioactive compounds can be encapsulated in polymers by electrospinning. • Natural polymers need to be cross-linked to prepare electrospun film. • Natural bioactive compounds can improve the function of electrospun film. • Electrospun film can improve the function of fruits and vegetables packaging. [ABSTRACT FROM AUTHOR]

The aim of this research was to prepare curdlan-based emulsion micro-gel particles with different concentration of the curdlan (0.5 g/100 mL, 1.0 g/100 mL, 1.5 g/100 mL, 2.0 g/100 mL, 2.5 g/100 mL), which respectively named as CEM(0.5), CEM(1.0), CEM(1.5), CEM(2.0), CEM(2.5). And the microstructural, rheological and texture properties of the emulsion micro-gel particles were investigated. Then, CEM(1.0) was used as a compound fat replacement in pork sausages and the effects of different replacement rates on the caloric value, texture and sensory quality of pork sausages were investigated. The results showed that the WPI and curdlan aggregation, the hardness, shear stress, the G ′ and G ″ moduli of the curdlan-based emulsion micro-gel particles significantly increased with increasing curdlan concentration. CEM(1.0) has the closest sensory quality to pork back fat and uniform inner structure. Digestion behaviors of CEM(1.0) showed that the curdlan gel network can not only delay the lipid digestion, but also inhibit the lipid digestion. The results showed that curdlan-based emulsion micro-gel particles can be used to replace 40% fat to produce low-fat pork sausages which had similar sensory acceptance with full-fat samples. • The curdlan-based emulsion micro-gel particles (CEM) prepared by heat-shearing. • The influence of the curdlan concentration on the CEM was investigated. • CEM(1.0) could be selected as a replacement of pork back fat. • The curdlan gel network can delay and inhibit the lipid digestion. • CEM(1.0) can be used to replace 40% fat to produce low-fat pork sausages. [ABSTRACT FROM AUTHOR]

As traditional edible fungi, Monascus spp. have been widely used as folk medicine, food colorants, and fermentation starters in East Asian countries for more than a thousand years. However, the presence of citrinin, which has nephrotoxic, hepatotoxic, and carcinogenic activities, raises suspicions about the safety of Monascus products. Citrinin biosynthesis in Monascus is known to occur via a polyketide pathway and a citrinin biosynthesis gene cluster, which include the characterized polyketide synthetase pksCT. A gene, orf6, encodes a protein that shows significant similarity to glyoxalase and is located between ctnE and orf1. This study analyzed orf6 function, and successfully obtained an orf6 disruption strain (Δ orf6). Citrinin production was significantly greater (3.6-fold) in the Δ orf6 strain than in the wild-type Monascus purpureus YY-1, and RT-PCR analysis further revealed increased expression of numerous genes of the citrinin biosynthesis gene cluster in Δ orf6. Therefore, orf6 proved to be a major inhibitor, directly involved in citrinin biosynthesis. Moreover, pigment production in Δ orf6 was reduced by approximately 30%, while the transcription levels of many genes involved in Monascus pigments (MPs) biosynthesis had increased. This dichotomy indicated that MPs and citrinin yields may be improved simultaneously; however, a portion of the pigments was consumed to protect the cells from oxidative damage in the Δ orf6 strain . An Δ orf6 revertant restored the citrinin and pigment yields to normal levels. This study makes a contribution to explore the citrinin biosynthesis pathway and provides some theoretical guidance to improving the safety of Monascus-related products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Starch/gelatin (S/G) films with three natural waxes were prepared by extrusion blowing. • S/G film with beeswax achieved a highly hydrophobic surface. • The waxes existed in S/G films as crystalline particles with various sizes. • The addition of natural waxes significantly affected the gelatinization of starch. To address the limitation of strong hydrophilicity of edible films, starch/gelatin (S/G) films incorporated with natural waxes (beeswax (BW), candelilla wax (CL), and carnauba wax (CB)) were fabricated by extrusion blowing. Rheological analysis demonstrated that the incorporation of natural waxes reduced storage modulus and complex viscosity of S/G blends. BW and CL weakened molecular interactions among film components, whereas CB did not. CB exhibited the strongest crystalline behavior after film formation. The degree of starch gelatinization and water vapor barrier property of films depended on wax type. The presence of waxes increased the water resistance and surface hydrophobicity of the films. However, CL and BW addition decreased the tensile strength of films. The highest water contact angle (102.6°), strongest thermal stability, and lowest water vapor permeability were found in S/G-BW film, which could be the optimal choice to produce highly hydrophobic edible films. [ABSTRACT FROM AUTHOR]

The surface waxes of 'Korla' pears can become greasy during storage when overripened, and the wax changes are considered to be responsible for this disorder, but the relationship between the wax changes and skin greasiness of 'Korla' pears remains unclear. We profiled the chemical and thermal changes in the surface waxes of 'Korla' pears as skin greasiness increased when stored at 25 °C. We also recorded the effects of treatment with 1-methylcyclopropene (1-MCP), which is known to interfere with this aetiology. The results show that as skin greasiness increased, there were steady increases in the more fluid wax compounds, mainly of the n-9 olefins (C17, C19, C21, C23 and C25). These fluid olefins were detected only in greasy fruit, and their amounts were highly correlated with greasiness. Separation experiments further confirmed that the accumulation of fluid olefins increased the fluidity of the solid alkanes of the 'Korla' pear waxes. The thermodynamic analyses show that melting temperatures and enthalpy both decreased with increases in wax fluidity. Moreover, the chemical and thermal changes in these waxes, along with greasiness can be suppressed by 1-MCP. These results indicate that the accumulation of fluid n-9 olefins raises wax fluidity, while the thermal analyses indicate that this effect could be similar in mechanism to those of the plasticizers used in the manufacture of synthetic polymers. • Liquid olefins of surface waxes greatly accumulated in greasy Korla pears. • Melting temperatures and enthalpy of surface waxes decreased in greasy Korla pears. • 1-MCP treatment suppressed the chemical and thermodynamic wax changes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Preharvest MeSA treatment could improve HAC and decrease LAC of apricot. • Total phenolics, especially (+)-catechin, was positively related to HAC in apricot. • MeSA enhanced the activities of phenolic synthesis enzymes and decreased PPO. • LAC was related to carotenoids which was regulated by carotenogenic genes. The carotenoid biosynthesis and phenolic metabolism were studied to explain the effect of methyl salicylate (MeSA) on the lipophilic antioxidant capacity (LAC) and hydrophilic antioxidant capacity (HAC) in apricot during postharvest storage. Our results indicated that the HAC of apricot was higher than LAC and mainly responsible for total antioxidant capacity of apricot. Preharvest spraying of MeSA (0.2 mmol L−1) could improve the value of HAC but declined LAC of apricot. The enhanced HAC in MeSA treated apricot was positively related to the increased content of phenolics, especially to (+)-catechin, which was catalyzed by the enzymes related to phenolic metabolism. While, the decline of LAC in apricot treated by MeSA could be attributed to the inhibition of carotenoids accumulation, which was regulated by carotenogenic genes. We concluded that MeSA could affect the lipophilic and hydrophilic antioxidant capacity of apricot by regulating carotenoid biosynthesis and phenolic metabolism. [ABSTRACT FROM AUTHOR]

Appropriate pretreatment of proteins and addition of xanthan gum (XG) has the potential to improve the stability of oil-in-water (O/W) emulsions. However, the factors that regulate the enhancement and the mechanism are still not clear, which restricts the realization of improving the emulsion stability by directional design of its structure. Therefore, the effects of whey protein micro-gel particles (WPMPs) and WPMPs-XG complexes on the stability of O/W emulsion were investigated in this article to provide theoretical support. WPMPs with different structures were prepared by pretreatment (controlled high-speed shear treatment of heat-set WPC gels) at pH 3.5–8.5. The impact of initial WPC structure and XG addition on Turbiscan Indexes, mean droplet size and the peroxide values of O/W emulsions was investigated. The results indicate that WPMPs and XG can respectively inhibit droplet coalescence and gravitational separation to improve the physical stability of WPC-stabilized O/W emulsions. The pretreatment significantly enhanced the oxidative stability of WPC-stabilized O/W emulsions. The addition of XG did not necessarily enhance the oxidative stability of O/W emulsions. Whether the oxidative stability of the O/W emulsion with XG is increased or decreased depends on the interface structure of the protein-XG complex. This study has significant implications for the development of novel structures containing lipid phases that are susceptible to oxidation. [ABSTRACT FROM AUTHOR]

Chito-oligosaccharides (COSs) were encapsulated by the film-ultrasonic method into three nano-liposomes, which were uncoated liposomes (COSs-Lip), chitosan-coated liposomes (CH-COSs-Lip), and sodium alginate (SA)/chitosan (CH)-coated liposomes (SA/CH-COSs-Lip). The physicochemical and structural properties, as well as the stability and digestive characteristics, of all three nano-liposomes were assessed in the current study. Thereafter, the characteristics of intestinal absorption and transport of nano-liposomes were investigated by the Caco-2 cell monolayer. All nano-liposomes showed a smaller-sized distribution with a higher encapsulation efficiency. The ζ-potential, Z-average diameter (Dz), and polydispersity index (PDI) demonstrated that the stability of the SA/CH-COSs-Lip had much better stability than COSs-Lip and CH-COSs-Lip. In addition, the transport of the nano-liposomes via the Caco-2 cell monolayer indicated a higher transmembrane transport capacity. In summary, the chitosan and sodium alginate could serve as potential delivery systems for COSs to fortify functional foods and medicines. [ABSTRACT FROM AUTHOR]