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Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Protein content in food is an important indicator of the nutritional value of food, and it is also related to food safety and many other issues, therefore it is significant to accurately determine the protein content for the valuation of food nutrition and safety. The main elements in food include carbon, nitrogen, hydrogen and sulphur, of which nitrogen mainly comes from protein. The average nitrogen content in protein is 16%, so the conversion factor for “nitrogen-to-protein” is 6.25. Therefore, the protein content in food can be obtained by measuring the nitrogen content of food combined with “nitrogen-to-protein” conversion factor. The traditional methods of protein detection are Kjeldahl method, spectrophotometry, and Dumas combustion. The Kjeldahl method is timeconsuming and consumes a large amount of reagents, which can cause environmental pollution. Spectrophotometry is susceptible to interference and the quantitative curve is not easy to draw. Dumas combustion is expensive in terms of consumables. In this paper, a platform of tube furnacequadrupole mass spectrometer was set up to analyze the protein content in food. Food samples were heated at high temperatures in a tube furnace and combusted in an oxygen-rich environment. After the gas products were ionized, they were directly introduced into a quadrupole mass analyzer for detection, which eliminated the need for processes such as oxidation-reduction, adsorption-desorption by using the selection ion scan function of the mass spectrometer. Five kinds of food samples with different protein contents were selected as research object. Each food sample was weighed at 1g. The food samples were fully combusted in tube furnace at high temperature (1 300 ℃). The gas products were infused through a drying and filtering tube to remove water and smoke, and then entered the EI ion source through a capillary for ionization. By electronic ionization, nitrogen element characteristic ions, N+, NO+, and NO2+ are generated. The peak intensity of the NO2+ ions were detected by the selection ion scan function of the quadrupole mass analyzer. A standard curve for nitrogen quantification is plotted to be y=115.64x+1 896.9 with the correlation coefficient (R²) of 0.999 92 and the relative standard deviation (RSD) of 2.1%-6.1%. The nitrogen content can be calculated by using the peak intensity of NO2+ ions according to the standard curve. The experimental platform of tube furnace-mass spectrometer provides a green, rapid, accurate, and low-cost detection method for quantitative analysis of protein content in food. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the highland barley moisture, β-glucan, amylopectin and protein content rapid detection model was established based on the 4000~10000 cm−1 near-infrared spectrum and actual contents of 76 highland barleys. The results showed that SG convolution smoothing was the optimal spectral preprocessing method for the partial least squares (PLS) prediction model of moisture, amylopectin and β-glucan contents, while SG convolution smoothing+multiplicative scatter correction (MSC) was the optimal spectral preprocessing method for the PLS prediction model of protein content. In order to further improve the accuracy of the prediction model, the different characteristic wavelength selection algorithms including competitive adaptive reweighted sampling (CARS), successive projections algorithm (SPA) and variables combination population analysis and iterative retained information variable (VCPA-IRIV) were used on the prediction results of the model. The results showed that VCPA-IRIV treatment could effectively improve the determination coefficient of prediction of moisture, amylose and protein content prediction model, and reduce the root mean square error of prediction. The treatment of CARS had a remarkable effect on the prediction accuracy for the β-glucan content. Ultimately, the established prediction models of moisture, β-glucan, amylopectin and protein content for highland barley had good prediction accuracy with the appropriate Rp (0.9868, 0.9808, 0.9701 and 0.9879) and RMSEP (0.2042, 0.1846, 0.8135 and 0.2095) value, respectively. In conclusion, the rapid detection model of highland barley characteristic nutrient content based on near infrared spectroscopy established in this study had high accuracy, which would have certain guiding significance for processing enterprises to quickly understand the quality of raw materials and efficiently screen qualified raw materials.

Egg yolk is an important food ingredient because of its outstanding nutritional value and emulsifying properties. The insoluble particle structure present in egg yolk and heat treatment during food processing may lead to poor stability of egg yolk emulsion. Hydrolysis, as a safe, efficient and low-energy modification method, has been widely used in studies on improving the emulsifying properties of egg yolk. In this paper, the effects of hydrolysis on the molecular structure, physicochemical properties and emulsifying characteristics of egg yolk are reviewed. Taking into account the actual needs of production, the formation mechanism and removal process of off-flavor in egg yolk hydrolysis products are discussed. Finally, this review summarizes the application of the emulsifying properties of egg yolk in the field of food processing, with a view to providing theoretical references for research on the hydrolytic modification of egg yolk.

In this research, the differences in protein and fatty acid composition among camel, cow and goat milks were analyzed by gel electrophoresis (GE) and gas chromatography (GC). The GE results showed that there were differences in the proportion of proteins in camel milk from different regions, and the production process had a significant effect on both camel milk protein and milk fat globule membrane protein composition. There were significant differences in protein composition among camel, cow and goat milks, and camel milk did not contain β-lacglobulin or αs1-casein, while cow and goat milks did not contain immunoglobulin G2 (IgG2) or IgG3. Therefore, GE could be used for the identification of camel milk mixed with cow or goat milk. The GC results showed that 31 fatty acids were detected in both camel and goat milks, and 29 fatty acids in cow milk. Camel milk contained fewer short-chain fatty acids than cow and goat milks, while the contents of most long-chain fatty acids were significantly higher than those in cow and goat milks. Principal component analysis (PCA) of the fatty acid composition data showed a clear separation of milks from different species and a clear discrimination between pure and adulterated camel milk. PCA can be used for the identification and analysis of fatty acids in camel milk mixed with cow milk and goat milk.

Protein-based gels have attracted much attention due to their unique advantages in the field of food and medicine due to their optical transparency. Transparent gels are expected to become high-end protein-based gel foods similar to bird 's nest or their processing excipients （ materials ）. Exploring the difference mechanism of optical properties of egg white thermal gels is expected to become the key to overcome the high-quality utilization of egg white gels. In this paper, the formation mechanism and influencing factors of egg white gel transparency were reviewed. The formation mechanism of egg white thermal gel was analyzed in depth, the modification methods of protein were discussed, and the future research and development direction of egg white transparent thermal gel was prospected.

Protein content in food is an important indicator of the nutritional value of food, and it is also related to food safety and many other issues, therefore it is significant to accurately determine the protein content for the valuation of food nutrition and safety. The main elements in food include carbon, nitrogen, hydrogen and sulphur, of which nitrogen mainly comes from protein. The average nitrogen content in protein is 16%, so the conversion factor for “nitrogen-to-protein” is 6.25. Therefore, the protein content in food can be obtained by measuring the nitrogen content of food combined with “nitrogen-to-protein” conversion factor. The traditional methods of protein detection are Kjeldahl method, spectrophotometry, and Dumas combustion. The Kjeldahl method is time-consuming and consumes a large amount of reagents, which can cause environmental pollution. Spectrophotometry is susceptible to interference and the quantitative curve is not easy to draw. Dumas combustion is expensive in terms of consumables. In this paper, a platform of tube furnace-quadrupole mass spectrometer was set up to analyze the protein content in food. Food samples were heated at high temperatures in a tube furnace and combusted in an oxygen-rich environment. After the gas products were ionized, they were directly introduced into a quadrupole mass analyzer for detection, which eliminated the need for processes such as oxidation-reduction, adsorption-desorption by using the selection ion scan function of the mass spectrometer. Five kinds of food samples with different protein contents were selected as research object. Each food sample was weighed at 1 g. The food samples were fully combusted in tube furnace at high temperature (1 300 ℃). The gas products were infused through a drying and filtering tube to remove water and smoke, and then entered the EI ion source through a capillary for ionization. By electronic ionization, nitrogen element characteristic ions, N+, NO+, and NO2+ are generated. The peak intensity of the NO2+ ions were detected by the selection ion scan function of the quadrupole mass analyzer. A standard curve for nitrogen quantification is plotted to be y=115.64x+1 896.9 with the correlation coefficient (R2) of 0.99992 and the relative standard deviation (RSD) of 2.1%-6.1%. The nitrogen content can be calculated by using the peak intensity of NO2+ ions according to the standard curve. The experimental platform of tube furnace-mass spectrometer provides a green, rapid, accurate, and low-cost detection method for quantitative analysis of protein content in food.

Haematococcus pluvialis residue powder, which has been extracted with astaxanthin, was used as the raw material to prepare Haematococcus pluvialis protein by alkaline extraction and acid precipitation method. The protein structure of Haematococcus pluvialis was characterized, and the effects of pH and ion strength on the functional characteristics of Haematococcus pluvialis protein were studied. The results showed that the isoelectric point of Haematococcus pluvialis protein was 4.2. The molecular weight of the subunit was around 14.4, 18.4 and 38 kDa, respectively and the content of α-helix, β-fold, β-corner and disordered structure in the secondary structure was 14.86%, 18.47%, 40.3% and 26.37%, respectively. It contained 7 kinds of essential amino acids required by the human body, accounting for 36.38% of the total amino acid content. Microscopic observation showed that the protein of Haematococcus pluvialis was rod-shaped and sheet-like, with a rough and porous surface. With the increase of pH, the solubility, water absorption, emulsion capability, foam stability and foam stability of the protein of Haematococcus pluvialis increased first and then decreased, while the emulsification stability showed the opposite trend. With the increase of NaCl concentration, the foam capability, foam stability, emulsion capability and emulsification stability of the protein of Haematococcus pluvialis increased first and then decreased, while the solubility showed a trend of first decreasing, then increasing, and then decreasing again.

In order to investigate the characterisation and biological activity of the leaf protein extract of Lycium barbarum, alkaline extraction and acid precipitation method was used to extract Lycium barbarum leaf protein extract. And the physicochemical properties, functional properties, structural characterisation and bioactivities of Lycium barbarum leaf protein extract were analysed by the methods of water holding capacity (WA), oil-holding property (FA), thermal stability (TM), solubility (PS), froth capability (FC), emulsification capability (EC), and other indexes as well as by the sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV), Fourier infraredspectroscopy (FT-IR), and X-ray Diffraction (XRD), and the in vitro radical scavenging assays and enzyme inhibition assays. The results showed that the total amino acid content of Lycium barbarum leaf protein extract reached 344.00±10.49 mg/100 g, the molecular weight ranged in 40 to 55 kDa, the water WA and FA property were 2.70 and 3.43 g/g, and the denaturation temperature was 85.73 ℃. With the increase of pH, the PS, FC, EC and froth stability (FS) of Lycium barbarum leaf protein extract showed a tendency of first decreasing and then increasing, while emulsion stability (ES) was exactly the opposite. The surface of Lycium barbarum leaf protein extract had tightly connected pores and was in the form of lumps of uneven sizes, with characteristicabsorption peaks near 270 nm, appearing amide A, B, Ⅰ, Ⅱ, Ⅲ bands, and a complete triplehelix structure. The scavenging rate of superoxide anion and hydroxyl radical was 37.73% and 35.38% at the concentration of 10 mg/mL of Lycium barbarum leaf protein extract, respectively. The IC50 of α-glucosidase and α-amylase was 9.88 and 21.09 mg/mL, respectively. In conclusion, the Lycium barbarum leaf protein extract was characterised and structurally stable, had certain in vitro antioxidant capacity and could inhibit the activity of enzymes related to blood glucose metabolism. This experiment provides theoretical basis for the development, utilisation and deep processing of Lycium barbarum leaf protein extract.

In recent years, researchers have often modulated the sensory and functional properties of foods through the interaction among various food components. Phenolic acids, proteins and carbohydrates widely exist and play important roles in flour products. Until now, existing studies primarily concentrate on the interactions of phenolic acid with protein and carbohydrate, along with their applications in several fields such as food processing and healthcare. The intricate interactions in the phenolic acid-protein-carbohydrate ternary system impart different sensory and functional properties to flour products. In this article, we review the research progress on the interactions among phenolic acid, protein and carbohydrate and their influence on the sensory and functional properties of bread dough, hoping to provide theoretical guidance for the application of the ternary system composed of phenolic acids, proteins and carbohydrates in flour products.

In this study, the bactericidal activity and mechanism of slightly acidic electrolyzed water (SAEW) against Campylobacter jejuni were examined. The effect of available chlorine concentration (ACC), treatment time and protein addition on the bactericidal activity of SAEW were investigated. In addition, the killing effect of SAEW on multi-generational cultures of C. jejuni was analyzed. The bactericidal mechanism was explored based on the changes in cell membrane integrity, morphology, and contents. The results showed that the inactivation of C. jejuni by SAEW was positively correlated with ACC and treatment time. Exogenous protein significantly weakened the bactericidal efficacy of SAEW. C. jejuni did not develop resistance to SAEW within ten passages. SAEW could destroy the integrity of the cell membrane. After treatment with SAEW, the cell surface was sunken, wrinkled and broken, and nucleic acid, protein and ATP leaked out from the cells, indicating that cell membrane damage may be the major reason for SAEW to inactivate C. jejuni.

Sarcopenia, an age-associated loss of muscle mass and function, greatly increases the risk of fractures, falls, and death in older adults. The pathogenesis of which is mainly involves motor neuron loss, hormone imbalance, inflammatory factors, and insulin resistance, etc. Supplementing nutrients such as protein, amino acid， n-3, n-6 polyunsaturated fatty acids and vitamin and other nutrients can effectively prevent and treat the sarcopenia. This paper focuses on the pathogenesis and nutritional intervention of sarcopenia to provide a reference for the research of sarcopenia.

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ObjectiveTo study the effects of different heat treatments on milk digestion in vitro.MethodsThe dynamic human stomach-intestine Ⅳ+ was used to analyze the pH change， protein digestibility， gastric emptying and peptide distribution of four different heat-treated milk products： raw milk， pasteurized milk， ultra-high-temperature sterilized （UHT） milk and direct steam infusion （INF） milk.ResultsThe pH change trends of raw milk and pasteurized milk in the stomach were very similar. Pasteurized milk took the shortest time to digest into a near-fasting state in the stomach. The protein digestibility of pasteurized milk was also the highest， whereas that of UHT milk was significantly lower than the other three samples. The molecular weight of peptides generated by the four kinds of milk after in vitro gastric digestion was below 5 000 u. After in vitro gastrointestinal digestion， the molecular weight of the peptides reached below 1 000 u， which is easy for digestion and absorption by the human body. Pasteurized milk and INF milk have advantages in protein digestibility and the molecular weight analysis of peptides of their digestion products. However， the general trend was the same without significant differences： they were both superior to UHT milk.ConclusionThe in vitro digestion profiles of INF milk and pasteurized milk were the same， which were better than those of UHT milk， providing consumers with a new choice for dairy products.

To solve the problem of taste loss of new retail prepared fish after freezing and reheating. The changes of moisture content, water holding capacity, water distribution, and microstructure in pre-fried fish were analyzed during frying, freezing and reheating processes. The results showed that with the increase of freezing-thawing cycles, a significant decrease of the moisture content (P

Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tree peony is an emerging oil crop that has received widespread attention in recent years. Studying the nutritional composition and loss patterns of tree peony seeds is not only a fundamental requirement for the tree peony planting and processing industry, but also of great significance for the development of related industries such as tree peony medicine and food. Traditionally, the number of related studies is relatively small, and the available research data are even rarer. This article mainly takes mature seeds of characteristic peonies from the Tongling area and the main production area Bozhou as samples. Firstly, the authenticity and viability of the seeds are identified using microscopy and TTC staining, and then the seeds are powdered for future use. Secondly, the soxhlet extraction method was used to measure the crude fat oil content in peony seeds, which ranges from 22.67% to 29.66%. The protein content in peony seeds was measured to be around 11.76%-21.17% using the second method of food protein determination standard method - ultraviolet spectrophotometry. After methyl esterification of fresh oil from tree peony seed oil, it was separated and detected by GC-MS (GC7890B-MSD5977A gas chromatography-mass spectrometry). Further retrieval was conducted using the NISTsearch2.0 standard spectral library, and artificial spectral analysis was conducted in conjunction with relevant literature to determine the 31 fatty acid compositions of tree peony seed oil. Finally,? the relative content of each component was calculated using peak area normalization method. After acid hydrolysis of fresh oil from tree peony seeds, 16 amino acids and their contents were measured using Hitachi L-8900 high-speed amino acid analyzer. The dataset for determining the nutritional composition of tree peony seeds provides preliminary information on the nutritional composition of tree peony seeds under different production and storage conditions, which has direct academic reference value for tree peony seed germination, seed processing, and reasonable storage. [ABSTRACT FROM AUTHOR]

旨在为低变性豆粕制备腐竹提供参考，分析了豆粕陈化对豆粕中蛋白质结构性质（溶解度、粒径分布、蛋白质组成）和氧化程度（巯基含量、表面疏水性、羰基含量）的影响。同时，以新鲜豆粕和陈化豆粕为原料制备腐竹，考察豆粕陈化对腐竹制备（产率、基本成分、机械性质、颜色、耐煮性）的影响。结果表明：豆粕中的蛋白质在长时间储藏过程（相对湿度40%~50%，温度16 ℃，储藏时间150 d）中发生疏水聚集导致其溶解度降低，粒径增大和蛋白质组成改变，同时蛋白质氧化导致其游离巯基含量下降，降低了豆粕中蛋白质的共价结合能力；新鲜豆粕制备的腐竹在产率和蛋白质利用率上显著高于陈化豆粕，同时在机械性质、亮度和耐煮性上也显著优于陈化豆粕。综上,豆粕陈化导致豆粕中蛋白质的成膜能力下降，不利于制备高产率和良好品质的腐竹。In order to provide a reference for the preparation of yuba from low-denatured soybean meal, the effects of soybean meal aging on the protein structure properties (solubility, particle size distribution, protein composition) and oxidation degree (sulfhydryl content, surface hydrophobicity, carbonyl content) were analyzed. In addition, fresh soybean meal and aged soybean meal were used as raw materials to make yuba, and the effects of soybean meal aging on the preparation of yuba (yield, basic composition, mechanical properties, color, boiling resistance) were investigated. The results showed that the hydrophobic aggregation of protein in soybean meal during storage (relative humutidy 40%-50%, temperature 16 ℃, storage time 150 d) led to the decrease of solubility, increase of particle size and change of protein composition. Protein oxidation led to a decrease in the content of free sulfhydryl, which reduced the covalent binding capacity of protein in soybean meal. The yield of yuba and utilization of protein prepared by fresh soybean meal were significantly higher than those of aged soybean meal, and the mechanical properties, brightness and boiling resistance of yuba prepared by fresh soybean meal were significantly better than those of aged soybean meal. In conclusion, the aging of soybean meal leads to the decrease of the film-forming ability of protein in soybean meal, which is not conducive to the preparation of yuba with high yield and good quality.

In order to quantitate protein, a liquid chromatography-isotope dilution mass spectrometry method for the analysis of amino acids in protein hydrolysate was established. The protein was hydrolyzed at 130 ℃ in the presence of 6 mol/L hydrochloric acid solution, and separated by Hypercarb porous graphite carbon chromatography column and 0.1% perfluoropentanoic acid aqueous solution/acetonitrile mobile phase system. Five stable amino acids (proline, valine, leucine, isoleucine and phenylalanine) were selected for quantitative determination with their corresponding stable isotope markers as internal standard, and the absolute quantitative determination of protein was achieved by combining protein sequence information. The linear relationship of the five amino acids is good within the range of 10-1 000 ng/mL (R2>0.995), the limit of detection and the limit of quantification are between 0.02-0.07 ng/mL and 0.06-0.2 ng/mL, respectively. The recovery at three different levels is between 97.0%-102.4%, and the relative standard deviation is between 1.1%-3.0%. The analysis results of human IgG monoclonal antibody to nucleocapsid protein solution reference material of 2019 Novel Coronavirus and the measurement results of national metrological comparison of 2019nCovid nucleocapsid protein are satisfactory, which proves that the method has sufficient accuracy for protein determination.

Ice cream has the characteristic of thermodynamic instability. During processing, storage, transportation, and sales, temperature fluctuations cause recrystallization of ice crystals and then increase the average size of ice crystals, which leads to rough texture and poor taste of ice cream. Therefore, inhibiting the recrystallization of ice crystals in ice cream is the key to ensure the quality of ice cream. This paper reviews the formation mechanism and research progress of supercooling, nucleation, growth and recrystallization of ice crystals during freezing. The inhibitory effects of emulsifiers, stabilizers, sweeteners, and proteins in ice cream raw materials on ice crystal recrystallization are introduced in detail. Meanwhile, it also list the contents of freezing technologies such as ultrasonic assisted freezing, magnetic field assisted freezing, high-pressure assisted freezing, and electric field assisted freezing to inhibit ice cream recrystallization. The development direction of that is prospected, which provides a theoretical reference for adapting to the trend of online sales, developing new ice cream products and solving the problem of its crystal recrystallization.

In order to elucidate the mechanism of the changes in gel properties of bighead carp surimi during ultra-high pressure coupled heat treatment, this paper investigated the changes in gel properties, protein structure and water migration of bighead carp surimi during ultra-high pressure coupled heat treatments (300 MPa/5 min, 40 ℃/30 min, 90 ℃/20 min), and carried out clustered heat maps and Pearson correlation analyses. The results showed that ultra-high pressure coupled heat treatment significantly improved the gel properties of bighead carp surimi (P

ObjectiveThis study aimed to discuss the use of protein materials in formula food for special medical purposes to provide a reference for the selection of the protein materials， product registration management， and clinical use in the development and design of formula food for special medical purposes.MethodsThis study summarized and analyzed the requirements of the protein in terms of the regulations and standards， the characteristics of protein materials， and their use status in different types of formula food for special medical purposes from the perspective of evaluation.ResultsProtein plays an essential role in formula food for special medical purposes. The commonly used protein materials include whey proteins， casein and soybean protein isolates， hydrolyzed protein， and amino acids. Based on the different applicable people， proteins have different characteristics and clinical applications in nutritionally complete formulas， protein modules， and nutritionally complete formulas for a specific disease.ConclusionFollowing the current requirements of registration and standards and the literature review， studies on the characteristics of protein materials and human protein nutritional requirements are relatively well-established， but studies on proteins used in formula food for special medical purposes are still limited. Paying more attention to the basic research on the use of protein materials in formula foods for special medical purposes and the collection of data used in clinical studies is crucial.

Bioactive ingredients such as polyphenols and carotenoids have various health benefits such as anti-cancer and antioxidant activities. However, bioactive components are unstable and easily damaged in the gastrointestinal environment, making them unable to fully exert their functional effects. Proteins and polysaccharides can form complexes via non-covalent or covalent interactions, which have been widely used as encapsulation materials to enhance the stability and activity of bioactive compounds. This review summarizes the types of protein-polysaccharide complexes, and describes the application of the anti-solvent, pH-driven, thermal gelation and emulsification methods for the delivery of bioactive ingredients by protein-polysaccharide complexes. It is anticipated that this review will provide a reference for the research and application of bioactive compounds encapsulated in protein-polysaccharide complexes.

It has great significance to maintain the natural state of food and reduce the environmental pollution that use of bio-based packaging materials to research and development food packaging, because it has been unable to meet the demand of consumers for green, environmental protection and high-efficiency, for traditional food packaging. Edible films are attracting great attentions in food packaging due to their safety and zero waste property, among which, the protein often used in the preparation of edible films because of good mechanical properties and nutritional value. Essential oils extracted from aromatic plants, the broad-spectrum antibacterial and antioxidant properties give it great potential in food packaging. Incorporation of essential oils into edible protein-based films can effectively improve their properties, and cover the strong sensory properties of essential oils, meanwhile, the release rate of essential oils is controlled. This review covers the recent developments in protein/essential oils-based composite films, the formation mechanism of protein/essential oils-based composite films is discussed, the two composite methods of single essential oil and complex essential oil with protein-based composite films is introduced. Meanwhile, the application of protein/essential oils-based composite films in food is summarized. This study can provide some reference for the future development of protein/essential oils-based composite films.

Zein, soy protein and whey protein can interact with lecithin to form composite systems. Proper application of ultrasonic, high-pressure homogenization and spray drying can make the composite systems more stable, expanding their application in delivery systems and making them promising for application in the fields of food, medicine, and other industries. This review focuses on the effect of the three physical field techniques on the interactions of the three proteins with lecithin and their application to deliver bioactive substances and drugs. We believe that this review will provide a basis for improving the stability of protein-lecithin composite systems and its application in delivery systems.

Protein from peony seed meal was extracted by alkali dissolution and acid precipitation. The extraction process was optimized by single factor and orthogonal experiments, and the physical and chemical properties and functional properties including isoelectric point, molecular weight, secondary structure, foaming property and foaming stability of the protein were determined. The results showed that the influencing factors on protein yield were: pH>extraction time>extraction temperature>solid-liquid ratio. The optimal extraction conditions were under the optimum conditions of material liquid ratio 1:20 g/mL, extraction temperature 70 ℃, pH9 and extraction time 45 min, the yield of protein from peony seed meal was 79.83%±1.22%. SDS-PAGE showed that there were five kinds of protein with molecular weight, two of which were between 15~25 kDa, two of which were between 35~40 kDa, and one of which was between 55~70 kDa. Fourier infrared spectroscopy showed that the protein in peony seed meal was mainly α-helix and β-folding, containing intermolecular hydrogen bonds and a small amount of carbohydrate. The scanning electron microscope showed that the protein in peony seed meal was mainly composed of β-folding composition. Compared with soybean protein, peanut protein and pea protein, peony seed meal protein had a good oil holding capacity of 4.5 g/g, which was similar to soybean protein in foaming and emulsification. This study can provide a reference for the application of peony seed meal protein in the food industry.

The enzymatic hydrolysis of bovine bone marrow protein (BBMP) was optimized and its physicochemical properties and antioxidant activities were studied, aimed to explore the material basis of its potential medicinal and health benefits and enhance the comprehensive utilization value of beef bone. The degree of hydrolysis (DH), protein content, and 1,1-diphenyl-2-trinitrophenylhydrazine free radical (DPPH·) scavenging rate were used as evaluation indexes, combined with the results of structural characterization, the suitable enzyme was screened. The response surface methodology was used to the optimization of enzymatic hydrolysis of bovine bone marrow protein as the hydrolysis time, enzyme concentration, pH, and temperature were independent variables. Then, the physicochemical properties and antioxidant activities of the obtained hydrolysates were investigated. The results showed that pepsin was selected as the optimal protease for the preparation of BBMP pepsin hydrolysate (BBMP-PH). The optimum enzymatic hydrolysis conditions were time 2 h, enzyme concentration 2%, pH3, and temperature of 37 ℃. Under these conditions, the DH, protein content, and DPPH· scavenging rate were 36.07%, 37.05%, and 39.57%, respectively. The effects of four factors on the efficiency of enzymatic hydrolysis were ordered as: Enzyme concentration>enzymatic hydrolysis time>enzymatic hydrolysis temperature>pH. The results of physicochemical properties showed that the isoelectric point (pI) of BBMP-PH was about pH6, and the solubility, emulsifying activity, emulsion stability, and water holding capacity of BBMP-PH were up to their lowest value at pI, and the better when far from the pI. When pH was 2, BBMP-PH has the highest solubility (94.72%), whereas pH8 for the emulsifying activity and emulsion stability (1.11 m2/g and 101.37%). BBMP-PH had strong scavenging ability of DPPH·, hydroxyl (·OH), superoxide anion (O2−·), and 2,2'-azo-bis-3-ethyl benzothiazoline 6-sulfonic acid (ABTS+·) free radicals, and the half inhibitory concentration IC50 were 0.65, 1.16, 0.35, 0.57 mg/mL, respectively. When the protein concentration was 1 mg/mL, the total reducing power was 0.88. This paper provides a reference for the high-value utilization of bovine bone marrow resources and the development of peptide-originated functional foods.

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Copyright of Science & Technology of Food Industry is the property of Science & Technology of Food Industry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

为给膨化大豆粉相关产品的开发和应用提供参考，根据生产实践经验，总结了在无抗大环境下膨化大豆粉的生产加工技术、关键设备和关键指标控制，并对膨化大豆粉在仔猪、奶牛、水产和家禽饲料中的应用研究情况进行了综述。原料大豆经除杂、破碎、粉碎、调质、膨化、冷却、干燥、破碎等工艺生产膨化大豆粉，膨化大豆粉生产关键设备包括原料破碎机、锤片式粉碎机、调质器、膨化机、翻板冷却器、成品破碎机等。膨化大豆粉关键指标为抗营养因子（脲酶活性0.01～0.03 U/g）、氢氧化钾蛋白质溶解度（75%~80%）、脂肪（17%～20%）、粗蛋白质（35%～39%）、水分（≤12%）、颗粒度（0.85 mm筛网过筛率≥90%）等，可通过调节工艺参数和加工工艺等方式，控制关键指标。膨化大豆粉可用于仔猪、奶牛、水产、家禽的饲料中，具有促进消化吸收、提高生产性能等优点。综上，膨化大豆粉生产工艺简单，同时对提高养殖经济效益具有十分重要的意义。In order to provide reference for the development and application of extruded soybean powder products, the processing technology of extruded soybean powder in non-resistant environment, key equipments and key control indicators were summarized according to the practical experience of production.In addition, the applications of extruded soybean powder in piglets, dairy cows, poultry and aquatic feed were overviewed. Extruded soybean powder was produced by the process of impurity removal, crushing, grinding, conditioning, extruding, cooling, drying and crushing. The key equipments of the extruded soybean powder production included raw material crusher, hammer mill, conditioner, extruder, flip plate cooler, finished product crusher and other equipment. The key indicators of extruded soybean powder were mainly anti-nutritional factors (urease activity 0.01-0.03 U/g), KOH nitrogen solubility index(75%-80%), fat (17%-20%), crude protein (35%-39%), moisture (≤12%), and particle size (0.85 mm screen passing rate ≥90%), which could be controlled by adjusting production process and process parameters. Extruded soybean powder could be used in the feed of piglets, dairy cows, aquatic products and poultry, which had the advantages of promoting digestion and absorption, improving production performance. In summary, the production process of extruded soybean powder is simple, and it has a very important significance for improving the economic benefits of breeding.

Objective: To solve the problems of low accuracy, low efficiency, and strong manual dependence in existing milk protein detection methods. Methods: Based on hyperspectral imaging systems, proposed a combination of improved whale algorithm and Elman neural network for rapid and non-destructive detection of milk protein content. Optimized the whale algorithm through three aspects (chaotic mapping, adaptive convergence factor, and adaptive weight) to improve search accuracy, and optimized the Elman neural network parameters (weights and thresholds) after optimization. Analyzed the performance of the proposed non-destructive testing method through experimental analysis. Results: Compared with conventional detection methods, proposed method was optimal for multiple performance indicators in non-destructive testing of milk protein. The experimental method was optimal in multiple performance indicators for non-destructive testing of milk protein, with determination coefficient of 0.997 3, the root mean square error of 0.000 3, and the detection time of 1.56 seconds. Conclusion: The experimental method has high detection accuracy and efficiency.

Wound healing is a common physiological process in which a series of molecular and cellular events occur after tissue lesions begin to rebuild the barrier between the body and the external environment. Hydrogels have significant advantages in wound treatment. They can control the wound healing process in time and space, and effectively promote the healing of damaged tissues in the hydration environment. The prominent characteristics of polysaccharides and proteins can be used as effective wound dressings for preparing bionic multifunctional hydrogels. Combining biological molecules and supporting cells, hydrogels can further perform faster and better healing functions. This review mainly discusses the effects of natural derived polysaccharide and protein hydrogel wound dressings on wound pathophysiology, and their ideal characteristics, cross-linking mechanism and manufacturing technology.

In this study, foxtail millet was used as raw material. The purpose of research was to investigate the changes of the properties and structures of four foxtail millet proteins, including albumin, glutelin, gliadin and globulin, after treatment by extrudating with α-amylase. The results demonstrated the increased water holding capacities, decreased foaming abilities, as well as the loss of the contents of several amino acids of these foxtail millet proteins under all extrusion conditions. Additionally, after extruding with enzyme, the contents of these proteins decreased, whereas the emulsification abilities increased. Among these proteins, the emulsification ability of gliadin was increased, while the foam stabilities of gliadin and glutelin were enhanced. Additionally, extruding with amylase resulted in less protein bands of albumin and globulin on gel. Furthermore, the secondary and tertiary structures of these foxtail millet proteins were comparable along extruding with enzyme, with minor blue shift. In conclusion, extruding with enzyme could improve the properties of foxtail millet proteins, with little influence on the secondary and tertiary structures. These findings indicate that the pregelatinization foxtail millet flour obtained with enzymatic extrusion processing technology could be used for an ideal functional food resource.

Background Frailty can increase the risk of negative health-related outcomes in older adults. Protein supplementation may be an effective way to improve frailty, but there is disagreement about its effects on frailty. Objective To systematically evaluate the effects of protein supplementation on muscle mass, strength, and physical function in frail/pre-frail older adults. Methods Electronic databases of CNKI, Wanfang Data, CQVIP, PubMed, Embase, Web of Science, Cochrane Library, CINAHL and Medline were retrieved for randomized controlled trials (RCTs) of the effects of protein supplementation on muscle mass, strength and physical function in frail/pre-frail older adults published from inception to June 2022. After literature screening, the quality of eligible RCTs was evaluated, and from which relevant data were extracted. RevMan 5.4 was performed to explore the effects of protein supplementation on muscle mass, muscle strength and physical function in frail/pre-frail older adults. And for the outcome indicator of muscle strength (grip strength) , due to large amount of reported literature, this study will be based on the amount of protein supplementation (0.05) . The results of subgroup analysis showed that the effect of protein supplementation on the grip strength of the Asian population subgroup was significantly different from that of the European population subgroup in between-group comparisons (χ2=5.76, P=0.02) . Conclusion Protein supplementation may improve gait speed in frail/pre-frail older adults, but it does not show a significant advantage in improving their muscle mass, muscle strength and other physical functions. It is recommended to further investigate the effects of longer durations of supplementation, different types of protein supplemented, different amounts of supplementation and different regional populations on older adults with different frailty states, in order to find the best pattern of protein supplementation and provide a more sufficient evidence-based basis for frailty management.

This paper discussed the preparation of protein nutrients from mulberry leaves by ultrasonic extraction combined with ultrafiltration technology. In order to obtain the optimal conditions for ultrasonic assisted extraction of mulberry leaf protein, we used response surface methodology to optimize the preparation of crude extract of mulberry leaf protein. In addition, we used ultrafiltration technology to purify and concentrate the protein components in the crude protein extract of mulberry leaves, and optimized the ultrafiltration membrane flux by orthogonal test. The amino acid components of solid crude protein prepared by ultrasonic extraction coupled with ultrafiltration technology were determined by referring to the method in GB 5009.124-2016 National Standard for Food Safety and further analyzed its nutritional value. The results showed that the optimal extraction conditions were as follows: The ratio of liquid-material ratio was 29:1 mL/g, ultrasonic extraction at 360 W for 15 min, and heating in water bath at 42 ℃ for 34 min, and the protein yield was up to 5.56%. Using the ultrafiltration technology to purify and concentrate the protein components in the crude protein extract, the optimal purification conditions were as follows: Operating pressure 0.6 MPa, diluting the crude extract by 1 time, and concentration ratio: 4:1. Under these conditions, the membrane flux was 21.40 L/m2·h, and the purity of solid protein was over 35%. The total amino acid content of solid mulberry leaf protein prepared by ultrasonic extraction coupled with ultrafiltration technology was 22.22 g/100 g, and the ratio of essential amino acids to total amino acids and the ratio of essential amino acids to non-essential amino acids were higher than the FAO/WHO adult model values. It could effectively extract and purify protein components from mulberry leaves by ultrasonic extraction combined with ultrafiltration technology. The prepared mulberry leaf proteins have good nutritional value and might meet the nutritional requirements of adults.

In order to explore a kind of hot-air drying of Antarctic krill under variable temperature process, the drying time, protein, fat and astaxanthin content were taken as indicators, the effects of first phase of the drying temperature, second phase of the drying temperature and moisture content point on the drying effect of Antarctic krill were studied, the drying effect was evaluated by multi-index comprehensive scoring method, the drying technology of dried Antarctic krill was optimized by orthogonal optimization test based on single factor experiments. The results showed that the optimum hot-air drying of Antarctic krill under variable temperature process were first phase of the drying temperature 55 ℃, second phase of the drying temperature 85 ℃, moisture content point 50%. The dried Antarctic krill obtained by this optimized process were the content of protein, fat, astaxanthin and drying time 69.24%, 19.79%, 232.72 μg/g, 300 min, respectively, and the comprehensive score of drying effect was 99.05.