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In order to explore the antibiotics development potential of the endophytic fungus Apiospora malaysiana from Thamnolia subuliformis, the antimicrobial spectrum of Apiospora malaysiana against common pathogen was determined after comparing the effects of six commonly used methods for determination of in vitro antimicrobial activity. The effects of storage time, temperature, ultraviolet irradiation time, and pH on the stability of antimicrobial activities of Apiospora malaysiana in vitro were further investigated by using the most sensitive Staphylococcus aureus as the indicator bacterium. The results showed that there was no significant difference in the antimicrobial activity of Apiospora malaysiana in vitro by three methods (plate punching method, filter paper method, and Oxford cup method) (P>0.05). However, the results of the three fungal inhabition methods showed that the mycelial growth rate method was optimal (inhibition rate of 100%), the effect of the plate confrontation method was much lower than the former (inhibition rate of only 24.0%), and the filter paper diffusion method had no inhibiting effect. The results of in vitro antimicrobial test showed that Apiospora malaysiana had strong inhibiting effects on a variety of Gram-positive bacteria and pathogenic fungi, among which Staphylococcus aureus was the most sensitive (the diameter of the inhibition zone was 18.3 mm, highly sensitive). In addition, Apiospora malaysiana also had strong antimicrobial activity against pathogenic fungi such as drug-resistant Candida albicans (highly sensitive), Botrytis cinerea, and Rhizoctonia solani (inhibition rate of 100%). The results of the antimicrobial stability test showed that different storage time, temperature, and ultraviolet irradiation time had no significant effects on the in vitro antimicrobial activity of Apiospora malaysiana (P>0.05), but pH had a great effect on its in vitro antimicrobial activity (P

Flavonoids are an important group of polyphenolic compounds found in natural foods, showing great potential for the usage in food, pharmaceutical, nutraceutical, and cosmetic industries. Nevertheless, flavonoids are generally limited in their potential application in food industry due to their low solubility, poor stability and permeability, resulting in poor bioavailability. It is a promising strategy to use nanotechnology to prepare nanoparticles of flavonoids based on natural biological macromolecules and thus improve the physicochemical properties of flavonoids. Recent researches at home and abroad are comprehensive analyzed in this paper, and the structure and properties of flavonoids are briefly described. On this basis, examples of nanoparticles of various protein and polysaccharide matrices and related research results are presented in this paper to discuss their binding mechanisms and applicability. The development of flavonoid nanoparticles for applications in the food industry is also envisaged. The objective of this study is to provide a theoretical basis and rationale for the development and utilization of natural macromolecular nanoparticles of flavonoids.

Anthocyanins, also known as anthocyanin glycosides, can not only be used as natural pigments, but also have various biological activities, such as antioxidant, anticancer, and cardiovascular disease prevention. However, due to the poor stability of anthocyanins, they are prone to degradation and inactivation during product processing and storage, which limits the further application and efficacy of anthocyanins. In order to improve the stability of anthocyanins and expand the application potential of anthocyanins in different fields, this paper mainly introduces a variety of stabilized technologies of anthocyanins in recent years, such as acylation, esterification, pyranization, co-pigmentation, microencapsulation, nano-liposome, nano-emulsion and hydrogel technologies. In addition, the application status and prospects of steady-state anthocyanins as food additives, colorants, freshness indicators, dye sensitizers and so on in many fields are summarized, in order to provide reference for the large-scale development of anthocyanin products in the later stage.

Rutin has a variety of pharmacological activities, in order to solve the application defects caused by its poor water solubility. In this paper, rutin/hydroxypropyl-β-cyclodextrin (HPCD) inclusion complexes were prepared by solvent evaporation method and analysed for structure, solubility, antioxidant activity and stability. The analysis of the inclusion complex showed that HPCD could effectively encapsulate rutin in a molar ratio of 1:1, and its encapsulation efficiency and drug loading rate were 89.33% and 26.67%, respectively. The solubility of the inclusion complex in water was 51 times higher than that of rutin. After complexation, the crystal diffraction peaks of rutin disappeared and the temperature of the maximum weight loss increased from 266 ℃ to 318 ℃ and solid inclusion complex forms showed an irregular sheet-like structures indicating a successful complexation of rutin by HPCD. The IC50 of the inclusion complex for scavenging DPPH radicals and ABTS cationic radicals was significantly lower than that of rutin (P

Heat treatment is an important factor affecting the stability of the protein emulsion. This paper investigated the effects of different heat treatment temperature (30, 50, 70, 80 and 90 ℃, 30 min) on the physicochemical properties of tuna protein emulsion. The results showed that the emulsifying property of the heat-treated protein emulsion changed significantly compared with those without heat treatment (P

Peas had high nutritional values and low allergenicity as a bulk pulse. However, whole pea milk was prone to flocculation instability, which limited its application in food. In this paper, peeling peas were used as raw material and treated with high pressure homogenization coupled biological double enzymatic hydrolysis (medium temperature α-amylase and cellulase), and the stability and nutritional characteristics of whole pea milk were revealed under the optimal process through centrifugation precipitation rate and Box-Behnken design. The results showed that the stability of whole pea milk prepared by simultaneous enzymatic hydrolysis of α-amylase and cellulase was better than the counterparts processed with traditional filtering, individual enzymatic hydrolysis, and step hydrolysis of double enzymes. The optimal parameters of simultaneous enzymatic hydrolysis was as follows: Medium temperature α-amylase:cellulase was 4.5:5.5 (enzyme activity ratio, U/g starch), with a total addition of 12 U/g and 65 minutes of enzymic hydrolysis. The centrifugal precipitation rate of whole pea milk processed under the optimal conditions was the lowest (27.70%), and no significant precipitation stratification during 60 days of storage without filtration and without stabilizer. Compared with the pea milk obtained by the traditional individual nutrients formulation, the whole pea milk prepared under the optimized simultaneous enzymatic hydrolysis showed significantly improved stability. The starch digestion extent showed a reduce of 12.74%, while the protein digestion extent was increased by 16.41%. The study provides the theoretical guidance for the development of concentrated plant based milk.

Objective: Banana flower polysaccharide was used as raw materials to analyze the antioxidant activity and stability. Methods: Bioactive polysaccharide from banana flower was extracted using hot-water extraction method combining with alcohol-precipitation method. Initially, the chemical composition of banana flower polysaccharide was detected and analyzed. Then, the total antioxidant capacity (T-AOC), as well as DPPH, hydroxyl and superoxide anion radicals scavenging activities were utilized to analyze the antioxidant activity of banana flower polysaccharide in vitro. On this basis, the antioxidant stability of banana flower polysaccharide was evaluated further by simulating different food processing conditions, including light, pH value, temperature, metal ions, common food ingredients, as well as sterilization methods, using the hydroxyl radical scavenging activity as the evaluation index. Results: The extraction yield of banana flower polysaccharide was about 14.56%, and the total sugar content, uronic acid content, protein content, phenolic content and flavonoid content of banana flower polysaccharide were 515.61, 287.88, 53.46, 2.23 and 7.94 mg/g, respectively. The result in this paper showed that polysaccharide obtained from banana flower possessed good reducing power, as well as DPPH and hydroxyl radicals scavenging capacities. The antioxidant property of banana flower polysaccharide was degraded by lighting, but remained stable under strong acidic as well as alkaline conditions. Banana flower polysaccharide had good heat resistance, specially under heating 60~80 ℃ from 2 to 3.5 h, its antioxidant stability was strong. Then, the good antioxidant stability of banana flower polysaccharide was observed in the presence of Na+ metal ion, whereas the antioxidant activity of banana flower polysaccharide was decreased with the increasing in the concentration of K+, Fe3+ and Cu2+ metal ions. Additionally, the antioxidant activity of banana flower polysaccharide was improved within the common food ingredients such as citric acid and sodium benzoate, but was decreased under sucrose and glucose as common food ingredients. The sterilization methods had different degrees of adverse effect on the antioxidant activity of banana flower polysaccharide, hence, high pressure sterilization could be used for sterilizing banana flower processing products. Conclusion: Banana flower polysaccharide had good antioxidant activity. The environmental factors including continuous light, Fe3+ and Cu2+ metal ions, as well as sucrose and glucose as common food ingredients might have the great influence on the antioxidant activity of banana flower polysaccharide. Hence, the direct contact with these environmental factors should be avoided during the processing and storage of banana flower.

Edible jiaosu is one type of food with many bioactive substances, which is very beneficial to human health. The stability of edible jiaosu is the key and difficult point to the development to the new jiaosu products. Currently, many studies on edible jiaosu have been conducted both domestically and internationally. However, there has been no systematic induction and summary until now. Therefore, based on the existing research results, this article summarizes the detection models and evaluation indicators related to the stability of jiaosu products. It shows that the main models include the predicting shelf life dynamics models. The stability indicators mainly include the sensory evaluation, pH index, the functional evaluation, the content of activity, and the probiotic content, among which the sensory evaluation and the antioxidant activity are the main evaluation indicators for the most stability evaluation. The factors that affect the stability of edible jiaosu products include the production process conditions (breeding strain, and fermentation time), the post-processing and the storage environment. The summary shows that by selecting suitable strains or mixed strains for fermentation, reasonable adjustment of fermentation time, adopting appropriate sterilization and drying methods, other post-processing methods, and using the low temperature, dark, anaerobic conditions are all beneficial to improve the stability of jiaosu products. It is recommended to further explore the selection of advantageous strains, research on post processing techniques, and stability regulations for jiaosu processing in the future. In summary, this paper summarizes the evaluation models and indicators for the stability of edible jiaosu, pointed out that production the process conditions, the post-processing of edible enzyme products, and the storage environment have a significant impact on the stability of edible jiaosu, and proposed measures and suggestions to improve its stability. This work provides a theoretical reference basis and guidance for promoting the stability of edible jiaosu and the development of its related industries.

Natural astaxanthin is the strongest antioxidant in nature, and shows many physiological functions such as anti-inflammatory, anti-tumor and immune regulation. Astaxanthin has been widely used in the fields of food, medicine and cosmetics. However, natural astaxanthin is unstable and easily degraded during extraction, storage and processing. Therefore, many studies have focused on improving the stability of astaxanthin. In this paper, the factors and mechanisms affecting the stability of astaxanthin are introduced from three aspects: The astaxanthin structure, extraction solvent and the processing and storage environment. The basic principles, effects, advantages and disadvantages of existing astaxanthin stabilization systems, such as emulsions, microcapsules, liposomes, nanoparticles and nanodispersions are compared. The water solubility, stability and bioavailability of astaxanthin can be enhanced to varying degrees, while there are generally shortcomings of complex process and high cost. Future research should focus on the basic theory of various stabilization technologies, and promote the development of astaxanthin stabilization systems to be more efficient, green and intelligent with the help of molecular simulation technology.

In nature, more than 90% of lycopene exists in all-trans form, but cis-lycopene in human blood and tissues accounts for more than 50% of total lycopene, and the proportion of cis-lycopene in prostate tissue was 90%. Numerous studies have shown that cis-lycopene has higher bioavailability than trans-lycopene, and thus has higher nutritional value and potential for development and utilization. Therefore, the properties and structures of lycopene isomers, the effect of extraction methods on the isomerization of lycopene, the types of isomerization (thermal isomerization, photoisomerization, etc.) and the physiological functions of cis-lycopene are reviewed in this paper. The mechanisms of different isomerization processes are expounded, and the advantages and disadvantages of each isomerization process are summarized. It is hoped that this review will provide a theoretical basis for further research on lycopene isomerization and provide scientific guidance for the production of lycopene with high proportion of cis-isomers.

This paper studied the effect of propylene glycol alginate and pectin stabilization system on the stability and quality of drinking mulberry yoghurt. Based on the centrifugation sedimentation rate, particle size distribution, viscosity, Zeta potential, Lumisizer stability scan, and Turbiscan results of the mulberry yogurt, and combined with appearance and taste comparison of the mulberry yogurt, the pectin and PGA optimum combination that maintain the stability and taste of the mulberry yogurt are determined. The results showed that: Pectin played a major role in the stability of mulberry yoghurt. PGA had a good effect on water separation, whey separation and water retention of mulberry yoghurt. When the addition of pectin was 0.45% and PGA was 0.1%, the sensory evaluation of mulberry yoghurt was good, and the results were the best, the centrifugal sedimentation rate was only 0.12% and the particle size was only 0.731μm, Zeta potential absolute value was up to 34.95 mV, viscosity was 20.28 cP. Moreover, the storage modulus of mulberry yoghurt in this scheme was moderate, and the results of Lumisizer stability scanning and Turbiscan scanning were also the best. It could be seen that: The stable system constructed by the reasonable combination of PGA and pectin had a significant effect on improving the overall stability of drinking mulberry yogurt under UHT sterilization, improving the texture and taste of drinking mulberry yogurt, and improving the overall quality of drinking mulberry yogurt.

In this study, the antibacterial effects of five different ethanolic concentrations (0%, 55%, 75%, 95%, 100%) EELC (Ethanol extract of Yunnan Litsea cubeba) on two kinds of pathogenic bacteria were determined. Ethanol extracts which had the strongest antibacterial activity and their stability were analyzed. The inhibition zone diameter of different concentrations in ethanolic EELC against E.coil and S.aureus were determined by KB paper method. At the same time, using TTC (2,3,5-triphenyltetrazolium chloride) method detected the MIC of EELC to screen out the best antibacterial activity of EELC. At the end, the temperature, heat treatment time, pH and UV light stability of EELC were further studied. The results showed that 55% and 75% EELC had the best inhibitory effect on S.aureus and E.coli, with MIC of 19 and 819 μg/mL, respectively. 55% EELC treated at 40 ℃, the OD600 was 0.118, which had the optimal antibacterial activity. Furthermore, the antibacterial activity remained stable after treatment for 1~5 hours at this condition. There was no significant difference in antibacterial activity between the two groups after irradiation with 30W UV light for 10~60 min (P>0.05). The bacteriostatic activity decreased at pH4, while it remained at a stable level at pH6~10. 75% EELC was treated at 100 ℃, the retention rate of antibacterial activity reaching 92.88%, and no significant difference was found in antibacterial activity after heating at this temperature for 1~5 h (P>0.05). The antibacterial activity was significantly decreased at pH4~8 (P0.05). It was suggested tha, the 55% EELC had a high stability and low action concentration against S.aureus, while 75% EELC had a stable inhibition effect against E.coil. The results would provide a theoretical basis for the comprehensive utilization and development of Yunnan Litsea cubeba.

Rosemary is an important economic crop. Its extract contains phenolic acids, flavonoids, terpenes and other biologically active substances. It also has antioxidant and antibacterial functions, so it can be used as a natural antioxidant and bacteriostatic agent in production. In this paper, extraction and purification methods of rosemary, microcapsule technology, nanoparticle carrier technology and composite coating are reviewed, in order to improve the stability of the extract. The antioxidant and antibacterial activities of rosemary extract and its application in meat products, vegetables, fruits, oils and beverages are discussed. Finally, application deficiencies and potential for future research and promotion of rosemary extract are discussed.

Calcium is an essential nutrient and plays an important role in life and health. Insufficient calcium intake in the body can lead to kinds of diseases, such as rickets and osteoporosis. As more and more calcium chelated peptides are prepared from food in recent years, the advantages of calcium chelated peptides like good stability and high bioavailability have attracted much attention and calcium chelated peptides have been reported to be a kind of ideal calcium supplements. In this paper, the research progress of calcium chelted peptide is summarized, the preparation, separation and purification methods of calcium chelted peptide are introduced, the factors affecting its chelating ability are analyzed, and the ways to promote the bioavailability of calcium are also discussed, in order to provide help for the development and utilization of calcium chelted peptide in functional foods in the future.

Natural polysaccharides have numerous biological activities, a stable structure, a large molecular weight, and a high level of safety, making them a popular choice for use as emulsifiers in the food business. However, polysaccharides' strong hydrophilicity and insolubility caused them to perform poorly during emulsification in high-temperature and high-salt environments, restricting their widespread use. To improve their ability to form emulsions, polysaccharides can have their molecular weight, structure, hydrophobicity, and other functional qualities altered. This paper reviews the effects of physical, chemical, and biological modification methods on the molecular structure and emulsification properties of polysaccharides, as well as the status and progress of research on the use of modified polysaccharides in emulsions, and also analyzes the issues with the current modification methods and forecasts the future development trend, with the goal of providing a theoretical foundation for further research on improving the emulsification property and broadening their application fields.

As functional bioactive substances, anthocyanins have attracted more and more attention, but their application is limited by their poor stability and low bioavailability. As one of the three essential nutrients needed by the human body, protein has good biocompatibility and biodegradability. It is often used in food processing, but its functional properties need to be improved. Proteins and anthocyanins usually coexist in food, and can easily interact with each other both covalently and non-covalently. The non-covalent interactions are predominant, including hydrogen bonds, hydrophobic interaction, electrostatic interaction and van der Waals force. This paper summarizes recent progress in the research on the interaction between anthocyanins and proteins, including the effect of proteins on anthocyanin stability and bioavailability, the effect of anthocyanins on protein functional properties, and the application status of anthocyanin-protein complexes, which will provide a theoretical basis for the application of anthocyanins and proteins in food deep processing.

With the popularization of the concepts of whole grain health cognition and scientific diet, consumers are paying more and more attention to different forms of whole grain food. Whole grain drink is one of the important products made from whole grain, and the physical stability of whole grain drink is a major challenge in the process of research and development. Since whole grain drink is a thermodynamically unstable system of multiphase turbidite liquid with water as the continuous phase and starch, dietary fiber, protein as the dispersed phase, the separation speed of whole grain drink is fast, which seriously affected the acceptability of consumers. Based on literature review, the multiscale characterization methods of macroscopic, mesoscopic, microscopic and nano-scale for the stability of whole grain drink and characterization methods of the characteristic chemical components were summarized. This paper summarized the stability of whole grain drink characterized with multiscale methods, which could provide methodological guidance for the development of whole grain drink and facilitate the rapid development of whole grain foods.

Sweet protein as a kind of natural sweeteners, has low calories, high sweetness, and safety to eat. However, due to the raw material growth conditions, short expiry date and other restrictions, resulted high production costs. Gene engineering expression and production of sweet protein can improve its stability, contribute to expand the production scale, reduces production costs, and improve its performance more specifically. However, the research of applying genetic engineering to produce sweet protein, encountered many problems, including the loss of sweet taste due to improper folding and lack of post-translational modification, and the lack of food safety certification due to non-plant extraction, which cannot be recognized by the public. This paper systematically analyzes the application of genetic engineering in sweet protein production and related hot issues for the first time, and provides theoretical data for the future genetic engineering transformation of sweet protein.

Carotenoids have numerous biological activities which are beneficial for human health, and can be spontaneously aggregated to different aggregates in certain conditions. In this paper, the effects of different proportions of hydrated organic solutions and different adding sequences on the types of carotenoids aggregates (H aggregates, M monomer and J aggregates), formation conditions and stability of three carotenoids (astaxanthin, lutein and β-carotene) were investigated. The astaxanthin acetone solution, lutein ethanol solution and β-carotene acetone solution were mixed in two different dropping sequences: Water into organic and organic into water, according to the proportion of organic solvents in the total volume from 10% to 90%, and the resulting sample was observed and analyzed by the UV-vis absorption spectrum. These results showed that when the astaxanthin, lutein and β-carotene formed H aggregates the volume ratios of organic solvents were 10%~20%, 10%~50% and 10%~40%, respectively. Astaxanthin formed J aggregates at 30% and β-carotene formed J aggregates at 50%~70%, respectively. Lutein was a lutein monomer when organic solvent takes up 60%~90% of the total volume. The conditions for the formation of aggregates were similar to those of organic water in addition sequence. However, it was found that the movement of absorption peak in UV-vis spectrum was more obvious under the sequence of organic water addition. After the samples were placed at room temperature (25 ℃) for 24 h and 48 h, the stability of aggregates was investigated. The H aggregates of lutein remains unchanged, however the H aggregates of astaxanthin and β-carotene gradually transformed into J aggregates. This study provides data support for the formation conditions and stability of carotenoid aggregates, thus offering theoretical basis for the application of carotenoids and their aggregates in food, medicine, cosmetics and other fields.

In order to increase the viability of Bifidobacterium in microcapsules formation process and in human gastrointestinal system, the optimized additive amount of cryoprotectants complexed with xylo-oligosaccharides was determined by single-factor and orthogonal experimental test. The influences of optimal cryoprotectants on the properties of microcapsules were also studied in this paper. The results showed that the optimized cryoprotectants composition was 4% of xylo-oligosaccharides, 2% of glycerol, and 1% of sodium glutamate, which could achieve 81.5%±0.7% of embedding rate and 88.1%±0.3% of freeze-drying survival rate for Bifidobacterium in microcapsules. Compared to the blank group, the cryoprotectants adding group was increased 21.6% of final active bacteria loading rate. In addition, the surface of the microcapsules added with the cryoprotectants was smoother and denser than the blank group. In simulation human gastrointestinal system, after digested 2 h in artificial gastric juice, there were 65.9% of Bifidobacterium survived in cryoprotectants group, which increased 15.3% of survival rate comparing with blank group. The cryoprotectants also significantly improved the probiotic release from microcapsules in artificial intestinal fluid. After storage at 4 and 25 ℃ for 35 days, the number of survival Bifidobacterium in the microcapsules added with the cryoprotectants were 8.1 lg CFU/g and 7.0 lg CFU/g, which significantly (P

Objects: The object of this paper was to determine the taxonomic status of a newly isolated of thermophilic microalga, and to study the stability of its phycocyanin to evaluate its possibility of application in food. Methods: The newly isolated algal strain was morphologically observed by optical microscope, and identified its taxonomic status based on its 16S rDNA sequence and the phylogenetic tree analysis. The phycocyanin of the alga was obtained by ultrasound-assisted extraction, and the stability of phycocyanin was investigated and evaluated based on the changes of the optical density measured with spectrophotometer under different levels of temperature, illumination and pH. Results: The alga cell was rod shape, straight or arc sometimes, binary fission, and was a branch of genus Thermosynechococcus. A crude extract of phycocyanin with a purity of 0.941 and a color value of 196.53 was obtained from the alga, and the yield was 11.37% (for dry mass weight). The stability tests showed that the phycocyanin was stable for 3.5 h at the temperature 60 ℃, its optical density retained 91.4% after illumination of 6000 lux for 7 d, the color was stable kept pH4.0~8.0 for 3.5 h, but it exhibited a poor stability in strong acid or strong alkali. Conclusion: The isolated microalga is a strain of the genus Thermosynechococcus. Its phycocyanin has good thermal-stability, photo-stability and acid-base-stability, exhibiting encouraging possibility for food application.

This paper reviews the structure and stability of triplex nucleic acid, the progress of triplex nucleic acid-based fluorescence, electrochemical, colorimetric platform in detecting food borne hazards, and discusses the challenges and future development prospect of triplex nucleic acid-based detection technology in food safety field.

Lycopene is a very unstable fat-soluble pigment and is easily oxidized or isomerized during processing and storage. In recent years, microencapsulation has been used to improve the instability of lycopene. The microencapsulated lycopene can reduce the contact with the outside world, avoiding the adverse effects of the external environment, increasing the storage stability of lycopene, and improve its bioavailability in the intestine. The preparation, storage stability and bioavailability of lycopene microcapsules are reviewed in this paper, in order to provide a reference for the application of lycopene microcapsule technology.

Rice processing precision is an important index to evaluate rice quality. In this paper, a new technology for the detection of rice processing precision was studied. The rice samples were dyed by eosin y-methylene blue method, and then placed in the rice processing accuracy tester to determine the degree of leather retention, and then determine the rice processing accuracy level. Through the statistical analysis of the validation results among different laboratories, it was showed that the method has good repeatability, reproducibility, stability in line with the requirements of national standards, and meets the needs of quantitative detection of rice processing accuracy. The repeatability limit R and reproducibility limit r were calculated according to the inter laboratory validation data, and the method was standardized to guide the practical application.