{"title":"Tomato Pomace Ketchup: Physicochemical, Microbiological, and Sensory Characteristics","authors":"Stefanny Heriyanto, Andreas Romulo","doi":"10.21603/2074-9414-2023-4-2477","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-4-2477","url":null,"abstract":"Tomato (Solanum lycopersicum L.) is one of the most important crops that is extensively used in the food processing industry. During tomato processing, abundant by-products such as skins, pulps, seeds, and waste are generated and cause environmental burdens. To solve this problem, tomato pomace was subsequently used as a material for making tomato sauce. However, it is essential that the production of tomato ketchup meets the required standards. Therefore, it is important to analyze the physicochemical and sensory characteristics of the product. We aimed to study the effect of corn starch addition on the physicochemical and sensory properties of tomato ketchup made from tomato waste and to assess the acceptability of tomato sauce formulated with different concentrations of corn starch. Tomato ketchup was cooked at 90°C for 15 min and then hot-filled into a sterile glass bottle. It was then analyzed for physical properties (color, viscosity, and total dissolved solids), chemical properties (pH, titratable acidity, moisture content), microbiological quality (total bacteria, mold, and yeast), and sensory acceptance. The results showed that corn starch influenced the color characteristics of the tomato sauce. Adding more than 4% of corn starch increased the viscosity and total solids content significantly (p < 0.05). Also, corn starch addition decreased the water content and acidity, as well as increased the pH of the tomato sauce. Microbiological analysis showed no growth of bacteria, mold, or yeast in any of the test samples. According to sensory analysis, the tomato sauce with 1% of corn starch had the highest acceptance, while higher concentrations of corn starch decreased the texture acceptance. Our findings may indicate that, with proper formulation, tomato by-products can be used as raw materials to develop sustainable alternative value-added products that consumers accept organoleptically. Further investigations can be conducted in the pilot-scale studies to enhance the feasibility of tomato pomace ketchup as a commercial product.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139140534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Melnikova, Ekaterina Bogdanova, E. Rudnichenko, Mariya Chekmareva
{"title":"Micellar Casein in Rennin Coagulation, Cheese Dehydration, and Ripening","authors":"E. Melnikova, Ekaterina Bogdanova, E. Rudnichenko, Mariya Chekmareva","doi":"10.21603/2074-9414-2023-4-2465","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-4-2465","url":null,"abstract":"Micellar casein concentrate is a promising fractionation agent in skimmed milk production. It preserves the native structure of protein and changes the ratio of casein and whey proteins. Micellar casein concentrate reduces the consumption of raw materials, which makes it a promising component of milk-intensive protein foods. The research objective was to study the effect of micellar casein concentrate on rennin coagulation, cl ot dehydration, and cheese ripening. The study featured skimmed milk, micellar casein concentrate, normalized mixes, and cheese samples of the Rossiiskii brand. The chemical composition and properties were studied by standar d methods. The optimal ratio of casein and whey proteins was 95:5. It reduced the initial gelation time, facilitated casein micelles destabilization and subsequent flocculation, accelerated syneresis, and improved clot stability. The high protein mass content made it possible to halve the stirring and boiling time, as well as to increase the yield of the finished product by 15%. In the experimental cheese, the starter cultures growth had a longer lag phase while the exponential phase started on ripening day 30. The experimental sample also demonstrated a better starter microflora survival on day 60, which resulted in a better amino acid composition of the finished product. In this research, micellar casein concentrate was able to affect rennet coagulation, clot dehydration, and ripening. Its application in the standard technology for the Rossiiskii cheese required the following adjustments: a longer starter activation, starter cultures with high proteolytic activity and ability to hydrolyze bitter peptides, extra rennet, a two-fold reduction of second heating and stirring, and at least 45 days or ripening.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139140600","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Oksana Kozlova, Natalia Velichkovich, E. Faskhutdinova, O. Neverova, A. Petrov
{"title":"Methods for Extracting Immune-Response Modulating Agents of Plant Origin","authors":"Oksana Kozlova, Natalia Velichkovich, E. Faskhutdinova, O. Neverova, A. Petrov","doi":"10.21603/2074-9414-2023-4-2468","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-4-2468","url":null,"abstract":"Numerous adverse factors may violate the human immune system and trigger various diseases. Immune-response modulating agents, or immunomodulators, help the immune system to function properly. Biologically active substances extracted from medicinal plants are especially promising in this respect. The article reviews traditional and novel methods for extracting biologically active immune-response modulating agents from plant raw materials. The review covered articles published in English and Russian in 2019–2023 and indexed in Scopus, Web of Science, and eLIBRARY. Extraction efficiency depends on such factors as solvent, temperature, and particle size, but the method is the most important one. Traditional extraction methods include percolation, maceration, Soxhlet extraction, heat reflux extraction, and decoction. However, they are solvent-consuming and expensive. Modern extraction methods rely on carbon dioxide, microwave treatment, ultrasonic processing, and pressure. They proved quite efficient in extracting biologically active substances from ginseng (Panax ginseng). Carbon dioxide, or supercritical, extraction was able to isolate polyphenol quercetin from quince fruit (Cydonia oblonga) and other biologically active substances from alfalfa (Medicago sativa). Maceration with methanol was applied to meadowsweet (Filipendula ulmaria) while Soxhlet extraction proved especially effective with smoke tree (Cotinus coggygria), moorland spotted orchid (Dactylorhiza maculata), and greater butterfly-orchid (Platanthera chlorantha). Both traditional and novel extraction methods find their application in medicine and food science, where they yield plant extracts of biologically active immune-response modulating agents.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139141738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lyudmila Asyakina, Yuliya Serazetdinova, Anna Frolova, Natalya Fotina, Olga Neverova, Andrey Petrov
{"title":"Antagonistic Activity of Extremophilic Bacteria Against Phytopathogens in Agricultural Crops","authors":"Lyudmila Asyakina, Yuliya Serazetdinova, Anna Frolova, Natalya Fotina, Olga Neverova, Andrey Petrov","doi":"10.21603/2074-9414-2023-3-2457","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-3-2457","url":null,"abstract":"Wheat is a vital agricultural crop whose phytopathogens include fungi of the genera Fusarium and Alternaria. Synthetic pesticides, which are used to combat them, have a negative impact on the environment. Therefore, there is a need for developing safe and effective biopesticides. We aimed to create a consortium of extremophilic microorganisms isolated from natural sources to protect wheat from the diseases caused by Alternaria and Fusarium fungi.
 Ten isolates of extremophilic microorganisms were tested for their antimicrobial activity against Escherichia coli and their antagonistic activity against phytopathogens. Based on the results, we developed microbial consortia and evaluated their effectiveness in protecting wheat from phytopathogens.
 Five of the strains under study showed the highest activity, three of which were biocompatible, namely Leclercia sp., Sphingomonas paucimobilis, and Lactobacillus plantarum. Four consortia were created from these microorganisms, of which consortium B (with a 2:1:1 ratio of the strains, respectively) proved the most effective. In particular, it increased the area free from the phytopathogen by 4.2% compared to the average values of its individual microorganisms. Also, the consortium had a phytostimulating effect on wheat seedlings (germination of 73.2–99.6%) and protected the seeds infected with phytopathogens from morphometric changes.
 The resulting consortium can be used as a biopesticide since it is highly effective in protecting wheat from Alternaria and Fusarium pathogens.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135199946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ekaterina Lisovaya, Elena Viktorova, Anastasia Sverdlichenko, Mariet Zhane
{"title":"Effect of Ultrasonic Exposure on the Efficiency of De-Oiling Fluid Lecithins","authors":"Ekaterina Lisovaya, Elena Viktorova, Anastasia Sverdlichenko, Mariet Zhane","doi":"10.21603/2074-9414-2023-3-2447","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-3-2447","url":null,"abstract":"De-oiling fluid lecithin is a resource- and energy-intensive process that provides a phospholipid isolate with a high content of phospholipids. Ultrasonic exposure is one of the most effective and easy-to-implement physical methods that intensify this chemical-technological procedure. This article describes the effect of ultrasonic exposure on the efficiency of de-oiling fluid lecithins.
 The research featured soy lecithin (fluid, partially de-oiled, phospholipid isolate). The de-oiling process involved acetone as a solvent and included three 10-min stages at a temperature of 40°C. The ratio of lecithin:acetone (by weight) was as follows: stage I – 1:7, stage II – 1:6, stage III – 1:5. The systems of fluid lecithin – acetone and partially de-oiled lecithin – acetone underwent ultrasonic treatment during the de-oiling process at different specific power and exposure time. As a result of filtration, phases separated into an acetone solution of neutral lipids and phospholipids. The phospholipid isolate was dried in a vacuum oven at 5 kPa and 40°C. Each stage ended with the following measurements: the content of phospholipids in partially de-oiled lecithins, the content of phospholipids in the phospholipid isolate, and the extraction degree of neutral lipids after distilling the solvent from the acetone miscella.
 The specific power in the lecithin – acetone system was 0.28 W/cm3 at de-oiling stage I and 0.36 W/cm3 at stages II and III. Three minutes of ultrasonic exposure at stages I and II and two minutes at stage III reduced the acetone consumption by 1.2 times. The resulting phospholipid isolate yielded by 3.3% more phospholipids than the control sample, which presupposed no ultrasonic treatment.
 Ultrasonic exposure proved to be an effective and solvent-saving three-stage method that intensified the process of de-oiling fluid soy lecithin. The study specified the optimal technological modes for obtaining a phospholipid isolate with a high content of phospholipids (98.6%), which can be recommended as a food additive.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of Dry Aging on Beef Muscle Proteins","authors":"Galina Gurinovich, Irina Patrakova, Vladislav Khrenov, Marina Patshina, Antonina Shevchenko","doi":"10.21603/2074-9414-2023-3-2462","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-3-2462","url":null,"abstract":"Meat is an inherent part of human diet. Its quality develops at different stages of production, storage, and processing. In this respect, the stage of aging is especially important. This technology makes it possible to regulate biochemical processes in meat raw materials. Long-term dry aging is a promising method that presupposes conditions that limit the growth of microorganisms. The transformations in the protein component are an important but understudied aspect of meat quality formation during dry aging.
 The research featured Hereford beef carcasses of Siberian breeding. The samples were isolated from the inner part of bone spinal-lumbar cuts after 21, 35, and 42 days of dry aging under the following conditions: 0–1°C, 74–75% relative humidity, 0.5 m/s air velocity. The samples were subjected to dry aging after 24 h at 4°C. The fractional composition of proteins was controlled by vertical electrophoresis in a Mini-Protean Tetra System chamber. The amino acid composition was defined by high-performance liquid chromatography in a Shimadzu LC-20 Prominence liquid chromatograph with a Shimadzu SPD20MA diode-matrix detector and a Kromasil C-18 separation column. The protein digestibility was measured by sequential exposure to pepsin-trypsin proteinase system under simulated gastric digestion.
 Long-time dry aging triggered proteolysis under the action of endogenous enzymes. The electropherogram analysis showed that the proteolytic changes in high-molecular myofibrillar proteins of high-quality beef became more pronounced after a longer maturation period. The distribution of protein fractions by dry aging stages indicated a different rate of degradation of contractile, regulatory, and cytoskeletal proteins. As a result, the structural integrity of muscle fibers degraded, the meat grew tender, and the proteins became more available to digestive enzymes. The amino acid and protein digestibility analyses in vitro demonstrated an increase in the nutritional value of beef and the availability of proteins to the action of proteinases after 42 days of dry aging.
 Long-term dry aging of high-quality beef increased the digestibility of muscle proteins as a result of proteolysis that accompanied the accumulation of low-molecular fractions. According to the amino acid analysis, the optimal result was most pronounced on day 42 as proven by the moderate oxidative changes in proteins.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Automated Measurement of Air Bubbles Dispersion in Ice Cream Using Machine Learning Methods","authors":"Igor Korolev","doi":"10.21603/2074-9414-2023-3-2448","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-3-2448","url":null,"abstract":"Ice cream is a popular cold dessert. Its air phase consists of tiny bubbles with an average diameter of 15–60 µm. New ice cream formulations depend on the way the composition and production factors affect the air phase. As a result, ice cream producers need new time-saving and reliable methods to determine dispersion. The research objective was to create a computer program for marking the position of centers and diameter of air bubbles on microscopic images of a bounding circle type. \u0000The review part included 20 years of Russian and English publications on microscopic research methods in ice cream production indexed in Web of Science and Russian Research Citation Index. Microscopic images of ice cream air phase were obtained using an Olympus CX41RF microscope with a magnification of ×100. The automatic markup program employed the Python programming language, the Keras machine learning library, and the TensorFlow framework. The models were trained using the NVIDIA GTX video accelerator. \u0000The review showed that the dispersion of ice cream air phase depends on its composition and the freezing parameters whereas bubble formation is usually described in line with the existing foaming theories. A training data set was obtained by manual labeling of microscopic images. The optimal number channels in the convolutional layers of a neural network with LeNet-type architecture was determined, which made it possible to classify images as spheres or non-spheres with an accuracy of ≥ 0.995. The sliding window method helped to determine the limits of the neural network triggering for the sliding window method were determined, which reached 7.5% of the diameter with lateral displacement and 12.5% with scaling. The developed algorithm automatically marked bubbles on microscopic images. The error in determining the average diameter was below 1.8%. \u0000The new method for automated calculation of the number and diameter of air bubbles in ice cream proved to be user-friendly. It can be found in public domain, and researchers are free to adapt it to solve various computer vision issues.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sergey Bredikhin, Alexander Martekha, Vasily Toroptsev, Yuliya Kaverina, Igor Korotkiy
{"title":"Sonochemical Effects on Wheat Starch","authors":"Sergey Bredikhin, Alexander Martekha, Vasily Toroptsev, Yuliya Kaverina, Igor Korotkiy","doi":"10.21603/2074-9414-2023-3-2460","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-3-2460","url":null,"abstract":"The food industry uses sonochemical treatment as part of emulsification, homogenization, and dispersion, as well as to modify viscosity and structure. Starch is one of the most common food ingredients, both as a raw material or a property-modifying additive. The research objective was to study the effect of sonochemical action on the structural and mechanical properties of wheat starch suspensions.
 The study involved suspension samples with 10% wheat starch. The suspension samples were treated with ultrasound using an ultrasonic device Volna-M model UZTA-1/22-OM or in an ultrasonic bath (22 kHz; 100, 150, 300, and 400 W). The treatment time was 15 and 30 min. The rheological, physical, and textural properties were recorded according to conventional methods before and after the treatment.
 The ultrasonic treatment caused mechanical damage to the starch, making it more accessible to moisture when heated. As a result, the structural, mechanical, and rheological properties of starch suspensions changed. All the studied suspensions had a non-Newtonian character. The ultrasonic treatment increased their consistency coefficient from 28.12 to 152.75 µPa·s. The gelatinization temperature of all experimental starch suspensions dropped from 63.4 to 61.0°C. The short high-power ultrasound treatment reduced the strength of gels to 1.25 N compared to that of native starch gel (4.28 N).
 In this research, the ultrasound treatment of wheat starch suspensions modified the structural, mechanical, and rheological profile of starch and proved able to replace some conventional starch modification procedures, i.e., chemical, physical, or enzymatic. The new approach can provide modified starches of a preset quality while reducing energy costs and processing time.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Andrei Khishov, Tatiana Balagula, Olga Lavrukhina, Aleksey Tretyakov, Olga Ivanova, Elizaveta Kozeicheva
{"title":"Microbiological Contamination of Food Raw Materials and Ready-To-Eat Foods: Analytical Review","authors":"Andrei Khishov, Tatiana Balagula, Olga Lavrukhina, Aleksey Tretyakov, Olga Ivanova, Elizaveta Kozeicheva","doi":"10.21603/2074-9414-2023-3-2451","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-3-2451","url":null,"abstract":"Microbiological contamination changes the qualitative and quantitative profile of food, which makes it an important issue of food safety systems. Finished products with components of animal origin or combined vegetable and livestock raw materials are especially prone to microbiological contamination. This review features the most common sources of microbiological contamination and its prevention in finished products.
 The review covered 20 years of English and Russian scientific articles and standards indexed in Scopus, ScienceDirect, PubMed, and eLIBRARY.RU. The descriptors included microbiological contamination, food raw materials, and ready-to-eat products. The analysis involved some older publications, provided they possessed a high scientific relevance and/or a high citation index. The search criteria concentrated on the detection of microbiological contaminants in food raw materials and food products in Russia and abroad. The percentage of detections for individual groups of microorganisms was calculated as opposed to their total number.
 The data obtained can be summarized as follows. Regular industrial monitoring can minimize the risk of microbiological contamination. Complex finished products have a higher risk and require heat treatment. Composite products that cannot be succumbed to additional heat treatment need new technologies that minimize microbiological contamination, e.g., intensive cooling, shock freezing, electromagnetic processing, protective food coatings, etc.
 Even a small amount of animal raw materials may cause extra risk of contamination with Listeria monocytogenes, Salmonella enteritidis, etc. A mix of different raw materials changes the microbiological profile of the finished product. As a result, finished products have to be monitored throughout the entire shelf-life cycle, regardless of the percentage of animal raw material in the formulation.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Seasonal Variations in the Biological Value of Kyrgyz Donkey’s Milk Proteins","authors":"Nadira Turganbaeva, Mukarama Musulmanova, Nurudin Kydyraliev","doi":"10.21603/2074-9414-2023-3-2459","DOIUrl":"https://doi.org/10.21603/2074-9414-2023-3-2459","url":null,"abstract":"Due to its protein component, donkey’s milk is a multifunctional product with a wide range of beneficial physiological properties. It is known for its antioxidant, anti-inflammatory, rejuvenating, antimicrobial, and antitumor effects. However, the milk of Kyrgyz donkeys has not received proper scientific attention in this respect. This study analyzed the seasonal amino acid profile and biological value of milk obtained from Kyrgyz donkeys.
 The donkeys belonged to the Kyrgyz breed and inhabited the highlands of the Chui Region, Republic of Kyrgyzstan. The sampling took place in April, July, and September. The amino acid composition of milk proteins was determined by capillary electrophoresis. The biological value of proteins was assessed by amino acid score, index of essential amino acids (Auxerre index), utility ratio of essential amino acids, and utility ratio of amino acid composition.
 The analysis revealed 18 amino acids, including eight essential ones. The total content of amino acids in the spring samples was 1840.07 mg/100 g. In the summer samples, this value peaked at 2037 mg/100 g; in autumn, it dropped to 1264.35 mg/100 g. The changes could be explained by the seasonal differences in the diet. The ratio of essential to non-essential amino acids approached 1:1. The milk also proved to contain arginine, which is an essential amino acid for a juvenile organism. In the spring samples, its content was 2.5 times as big as in the autumn ones. Leucine and isoleucine were responsible for 1/3 of the essential amino acids (322.60 ± 19.35 mg/100 g). The summer samples demonstrated the maximal content of some other essential amino acids, except for valine and tryptophan, which appeared to be the limiting essential amino acids for donkey’s milk in the autumn period. Total essential amino acids in the spring, summer, and autumn samples amounted to 54.24, 59.26, and 34.77 g/100 g, respectively, which exceeded the value for the reference protein (27.46 g/100 g).
 Kyrgyz donkey’s milk proteins were of high biological value, regardless of the season, which means that donkey’s milk can become part of new functional products.","PeriodicalId":12335,"journal":{"name":"Food Processing: Techniques and Technology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135200798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}