Milk Mixtures Research Articles

Photonic Dipstick Immunosensor to Detect Adulteration of Ewe, Goat, and Donkey Milk with Cow Milk through Bovine κ-Casein Detection.

The quality and authenticity of milk are of paramount importance. Cow milk is more allergenic and less nutritious than ewe, goat, or donkey milk, which are often adulterated with cow milk due to their seasonal availability and higher prices. In this work, a silicon photonic dipstick sensor accommodating two U-shaped Mach-Zehnder Interferometers (MZIs) was employed for the label-free detection of the adulteration of ewe, goat, and donkey milk with cow milk. One of the two MZIs of the chip was modified with bovine κ-casein, while the other was modified with bovine serum albumin to serve as a blank. All assay steps were performed by immersion of the chip side where the MZIs are positioned into the reagent solutions, leading to a photonic dipstick immunosensor. Thus, the chip was first immersed in a mixture of milk with anti-bovine κ-casein antibody and then in a secondary antibody solution for signal enhancement. A limit of detection of 0.05% v/v cow milk in ewe, goat, or donkey milk was achieved in 12 min using a 50-times diluted sample. This fast, sensitive, and simple assay, without the need for sample pre-processing, microfluidics, or pumps, makes the developed sensor ideal for the detection of milk adulteration at the point of need.

Development of probiotic functional food and evaluation of its functional properties

Probiotics are beneficial microorganisms that enhance human health by improving intestinal microbial balance. It helps in improving digestive health, enhances immunity, and improves psychiatric health, cardiac health and weight management. The present study explores the potential of using probiotic microorganisms from lotus (Nelumbo nucifera) and colocasia (Colocasia esculenta) leaves as sources for starter culture bacteria for curd preparation. Four types of curd were developed: cow's milk with colocasia leaf starter culture (MC), cow's milk with lotus leaf starter culture (ML), red sorghum and cow's milk mixture with colocasia leaf starter (MRC), and red sorghum and cow's milk mixture with lotus leaf starter (MRL). Metagenomic analysis showed that MC curd contained Acetobacter sp., (51%), Lactococcus sp., (26%), and Leuconostoc sp., (18%), while ML curd had Lactococcus sp., (67%), Leuconostoc sp. (20%), and Lactobacillus sp., (10%). Physicochemical study of MRC and MRL showed 2.94 ± 0.84 % and 2.84 ± 0.14 % of carbohydrate content, respectively. The analysis of MRC and MRL showed a significant increase in the color parameter “a*” probably due to the presence of anthocyanin in red sorghum milk. The MRC and MRL showed higher antioxidant and anti-inflammatory activities. The MRL curd showed the highest glucose uptake and cytotoxicity in the L6 cell line and also demonstrated potent α-amylase inhibition (IC50 = 2.383 ± 0.286 μg/ml) compared to MRC (IC50 = 13.02 ± 0.112 μg/ml). Thus, in-vitro anti-diabetic activity of red sorghum-fortified curds was found superior to MC and ML curds. This study suggests that red sorghum fortification enhances curd quality and provides notable health benefits.

Investigation of the influence of milk protein genotype on the process of fermentation of milk curds by mesophilic lactic acid streptococci

The relevance of this study lies in the fact that the majority of commercial milk processed into fermented dairy products is a mixture of β-casein genotypes. The increasing use of A2 milk in the dairy industry necessitates the development of scientifically grounded technologies for the production of fermented products, as casein genotype modifications can affect the course of technological processes and require adjustments to production parameters. The study aimed to determine the impact of genetic modification of the β-casein protein in cow’s milk on the fermentation process of milk mixtures during the production of fermented dairy products. Research methods included chemical, physical, organoleptic, and microbiological methods (determination of the quality indicators of raw milk and fermented milk curds), and technological methods (determination of acid formation activity and viscosity). The initial characteristics of raw milk were investigated according to genotype, revealing no direct correlation. Changes in the physicochemical, microbiological, and organoleptic properties of fermented milk curds during biotechnological processing and storage were examined. Optimal technological process regimes were selected, and technological methods were chosen to minimise the influence of secondary factors on the experiment. A mixed culture preparation of mesophilic lactic acid lactococci, including L. Lactis ssp., was chosen as a starter culture. It was established that all 13 milk samples were suitable for biotechnological processing using mixed cultures of mesophilic lactic acid bacteria. As a result, it was concluded that the production of fermented dairy products from raw milk with the presented β-casein genetic modifications, A1A1, A1A2, and A2A2 – using L. lactis ssp. cultures – is possible using the classical technology and does not require adjustment of the technological conditions. The obtained results can be used in the dairy industry when developing technologies for fermented dairy products from A2 raw milk

Metagenome-assembled genomes from microbiomes fermenting dairy coproducts.

To advance knowledge of microbial communities capable of fermenting agro-industrial residues into value-added products, we report metagenomes of microbial communities from six anaerobic bioreactors that were fed a mixture of ultra-filtered milk permeate and cottage cheese acid whey. These metagenomes produced 122 metagenome-assembled genomes that represent 34 distinct taxa.

Effects of Adding Pectin to Milk in Varying Amounts on the Rheological Properties of Milk

Pectin, which is used as an additive in the food, cosmetics, pharmaceutical, and health sectors due to its safety, non-toxicity, low production cost, and high availability, is used as a thickener, gelling agent, brightener, stabilizer, emulsifier, and fat and sugar replacer in low-calorie foods. It is also used in milk and dairy products as a stabilizer to prevent proteins from clumping. In this study, the rheological properties of pectin and milk mixtures with pectin/milk powder (w/w) ratios of 0.1, 0.25, 0.5, 0.75, 1 and 1.5 were examined. First, a flow curve test was applied in the range of 0,01-1000 s-1 to obtain the viscosity curves and yield stress values of the samples. Then, an amplitude sweep test was performed at a fixed frequency of 10 rad/s and in the strain range of 0.01-100% to determine the linear viscoelastic range (LVR) of the samples and the solid and liquid structure of the samples. To determine the time-dependent behavior of the samples in non-destructive deformation, frequency sweep tests were performed at constant strain (0.01%) in the LVR range obtained from the amplitude sweep test and in the range of 0.1-100 rad/s. Finally, three interval thixotropy tests (3ITT) were performed to observe the structural recovery of the samples. As a result of rheological tests, it was determined that pectin-free milk showed Newtonian properties, other samples showed shear thinning properties, and viscosity values increased as the pectin rate increased. While all samples are solid at low strains, the liquid feature becomes dominant at high strains. It has been observed that as the pectin ratio in milk increases, the strain values at the yield point, where the liquid feature becomes dominant, also increase. Except for the sample with the highest pectin content, it was observed that the dominance of the storage modulus over the loss modulus was greater at low frequencies than at high frequencies. As a result of 3ITT, it was determined that the percentage of recovery at the 600th second increased as the pectin rate increased.

Construction of a Pickering interfacial biocatalysis system in skim milk and enzymatic transesterification for enhancement of flavor and quality

Despite considerable research efforts, lipase catalysis in a fluid milk system with aqueous multicomponent mixtures containing multiple microphases remains challenging. Pickering interfacial biocatalysis (PIB) platforms are typically fabricated with organic solvents or lipids and water. Whether a PIB with excellent catalytic performance can be constructed in complex milk mixtures remains unknown. Here, we challenged PIB with skim milk, a small amount of flaxseed oil, and phytosterols as a model system for transesterification and lipolysis to enhance quality and flavor. The amino-modified mesoporous silica spheres were employed as an emulsifier and carrier of lipase AYS. The conversion of phytosterol esters reached 75.5% at 1.5 h in prepared phytosterol ester-fortified milk with a content of 1.0 g/100 mL. The relative conversion rate remained above 70% after 6 cycles. In addition, the fortified milk showed an intensified and favorable effect on sensory traits through volatile flavor composition analysis. The findings provide a versatile alternative for PIB applications in complex environments, i.e., milk, which might inspire a new bioprocess strategy for dairy products.

The results of studies on the nutritional value of milk-pumpkin yogurt from combined milk

The research work is aimed at studying the chemical, nutritional and organoleptic properties of pumpkin milk yogurt produced from pumpkin using a mixture of mare and cow milk in various ratios (2/5, 3/5, 1/1) and establishing standardized quality parameters. The chemical properties of the resulting product have improved, including the amount of protein, fat content, fibers, and available carbohydrates. Adding pumpkin to yogurt did not significantly change calories. By adding pumpkin pulp to mixed milk, the pH value decreased and the acidity of the finished yogurt increased (P≤0.05). The content of β-carotene and water-soluble vitamins in mixed milk-pumpkin yogurt was significantly higher compared to the control sample. Thus, yogurt prepared by adding pumpkin pulp to a mixture of mare and cow milk has high nutritional and consumer properties and is recommended for use as a therapeutic and prophylactic product. The practical significance of the study and its results are based on the use of a mixture of mare's and cow's milk and the softness of hard-shell pumpkin in the production of yogurt. The addition of pumpkin allows to increase the detoxifying properties of the product and the sweetness of mare's milk due to the high content of milk sugar. In this way, functional properties can be imparted to the finished products, providing the sweet taste of yoghurt without added sugar or sweeteners.

Volatile compounds of Croatian cheese in a lamb skin sack prepared from a mixture of goat's and cow's milk

Volatile aroma compounds are one of the main parameters in consumer choice and acceptance of cheese. The traditional way of making cheese, still preserved in Croatia, is the anaerobic ripening of curds in a lamb or goat sack. Cheeses produced in such a way have a specific aroma. The objective of this study was to determine the volatile compounds of Croatian cheese in a lamb skin sack prepared from a mixture of goat's and cow's milk and relate them with the aroma of this traditional cheese. The cheese extracts were obtained by headspace solid-phase microextraction (HS-SPME) and ultrasonic solvent extraction (USE) and analysed by gas chromatography-mass spectrometry (GCMS). HS-SPME was performed at different temperatures (40, 50 and 60°C) using 2 fibres, divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fibre and carboxen/ polydimethylsiloxane (CAR/PDMS) fibre. Increasing the extraction temperature resulted in higher sorption of fatty acids on both fibres. A total of 28 volatile compounds were identified in the cheese samples including 13 acids, 10 esters, 2 alcohols, 2 hydrocarbons and 1 ketone. Results revealed that fatty acids were the predominant group of volatile compounds in all samples. In samples obtained by HS-SPME, the most abundant were hexanoic, octanoic, butanoic, acetic and decanoic acid while (Z)-octadec-9-enoic, hexadecanoic, decanoic and tetradecanoic acid were the most abundant in the sample obtained by USE.

Structure Response of Preadsorbed Saliva Pellicle to the Interaction between Dairy and Saliva Protein.

Using the surface characterization techniques of quartz crystal microbalance with dissipation, atomic force microscopy, and scanning electron microscopy, the structure of the salivary pellicle was investigated before and after it was exposed to dairy proteins, including micellar casein, skim milk, whey protein isolate (WPI), and a mixture of skim milk and WPI. We have shown that the hydration, viscoelasticity, and adsorbed proteinaceous mass of a preadsorbed salivary pellicle on a PDMS surface are greatly affected by the type of dairy protein. After interaction with whey protein, the preadsorbed saliva pellicle becomes softer. However, exposure of the saliva pellicle to micellar casein causes the pellicle to partially collapse, which results in a thinner and more rigid surface layer. This structure change correlates with the measured lubrication behavior when the saliva pellicle is exposed to dairy proteins. While previous studies suggest that whey protein is the main component in milk to interact with salivary proteins, our study indicates interactions with casein are more important. The knowledge gained here provides insights into the mechanisms by which different components of dairy foods and beverages contribute to mouthfeel and texture perception, as well as influence oral hygiene.

Study of the Microbiome of the Cretan Sour Cream Staka Using Amplicon Sequencing and Shotgun Metagenomics and Isolation of Novel Strains with an Important Antimicrobial Potential.

Staka is a traditional Greek sour cream made mostly from spontaneously fermented sheep milk or a mixture of sheep and goat milk. At the industrial scale, cream separators and starter cultures may also be used. Staka is sometimes cooked with flour to absorb most of the fat. In this study, we employed culture-based techniques, amplicon sequencing, and shotgun metagenomics to analyze the Staka microbiome for the first time. The samples were dominated by Lactococcus or Leuconostoc spp. Most other bacteria were lactic acid bacteria (LAB) from the Streptococcus and Enterococcus genera or Gram-negative bacteria from the Buttiauxella, Pseudomonas, Enterobacter, Escherichia-Shigella, and Hafnia genera. Debaryomyces, Kluyveromyces, or Alternaria were the most prevalent genera in the samples, followed by other yeasts and molds like Saccharomyces, Penicillium, Aspergillus, Stemphylium, Coniospotium, or Cladosporium spp. Shotgun metagenomics allowed the species-level identification of Lactococcus lactis, Lactococcus raffinolactis, Streptococcus thermophilus, Streptococcus gallolyticus, Escherichia coli, Hafnia alvei, Streptococcus parauberis, and Enterococcus durans. Binning of assembled shotgun reads followed by recruitment plot analysis of single reads could determine near-complete metagenome assembled genomes (MAGs). Culture-dependent and culture-independent analyses were in overall agreement with some distinct differences. For example, lactococci could not be isolated, presumably because they had entered a viable but not culturable (VBNC) state or because they were dead. Finally, several LAB, Hafnia paralvei, and Pseudomonas spp. isolates exhibited antimicrobial activities against oral or other pathogenic streptococci, and certain spoilage and pathogenic bacteria establishing their potential role in food bio-protection or new biomedical applications. Our study may pave the way for additional studies concerning artisanal sour creams to better understand the factors affecting their production and the quality.

Effects of Beverage Solvents on Disintegration Time and Dissolution Rate of Metronidazole Tablets

Drug Disintegration time refers to the period within which a mechanical break-up of compressed tablet dissolve upon exposure to physiological fluids within a short period of time into tiny granules upon ingestion, while drug dissolution rate becomes a key tool in understanding the importance for its bioavailability and therapeutic effectiveness. Hence, the objective of this paper was to assess the impact of seven different solvents, which includes five non-alcoholic beverages (Exotic juice, soft drink, coffee, milk, and milo), one alcoholic beverage (beer), one dilute acid (0.1 M HCl) and a control distilled water (dil. H2O) on the disintegration time and dissolution rate of metronidazole tablets. The distilled water was used as control. The results obtained show that the mean disintegration times were 2.28 ± 0.04 (0.1 N HCl), 4.21 ± 0.12 (beer), 3.24 ± 0.05 (coffee), 3.23 ± 0.07 (distilled water), 5.21 ± 0.09 (Exotic juice), 3.17 ± 0.06 (Fanta), and 16.16 ± 0.11 (milk). The mean dissolution rates on the other hand were 98.87 ± 0.12, 78.09 ± 0.09, 84.27 ± 0.11, 86.52 ± 0.40, 67.98 ± 0.09, 92.70 ± 0.50, and 44.94 ± 0.22 respectively. Metronidazole tablets disintegrated and dissolved more in 0.1 N HCL than in other mediums and less in milk. From this study, although the disintegration time and dissolution rate of metronidazole were not greatly affected by the different beverages except for Exotic juice, and the mixture of milk and Milo, care should be taken when replacing water with any beverage in ingesting tablets.

Use of Dry Milk Molasses with Lactulose in the Yogurt Production Technology with Ultrasonic Treatment

Dry milk molasses with lactulose is a product of processing by-products in the lactose production. Its use in the fermented milk drinks technology offers new opportunities to expand the food product range with a prebiotic effect. The research aims at studying the use possibility of dry milk molasses with lactulose in yogurt production technology, as well as to distinguish the ultrasonic treatment impact on the quality characteristics of finished products. The authors revealed that the use of dry milk molasses with lactulose in the yogurt production in an amount of 3 % of the total mass of the milk mixture enables to intensify the fermentation process and obtain a prebiotic fermented milk drink with high consumer properties. The study results demonstrated that the use of ultrasonic treatment with a frequency of 24 kHz and a specific power of 840–860 W/dm3 enables to obtain a finished product with improved quality characteristics in the production technology of yogurt with milk molasses with lactulose. Ultrasonic treatment facilitates a more finely dispersed structure formation of the milk mixture: at the end of the lag phase of the lactic acid cultures growth, the average diameter of protein particles and fat balls in a mixture with ultrasonic treatment is 1.47 and 2.89 times smaller, respectively, in relation to the fermented system without the ultrasound use. The results of microscopy, rheological and organoleptic properties determination of yogurt enable to conclude that there is a more homogeneous mesh protein matrix in the milk clot, the effective viscosity coefficient value increases (by 1.3–3.9 times), the appearance and consistency of the finished product improve during ultrasonic treatment.

THE INFLUENCE OF STARCH PRODUCTS ON THE RHEOLOGI-CAL, PHYSICAL AND CHEMICAL PROPERTIES OF YOGURT

Expanding the assortment of low-fat yogurt with natural structuring sweeteners and regulated quality indicators is an actual direction of scientific research. The purpose of the study is to study the patterns of influence of the products of enzymatic hydrolysis of corn starch with different dextrose equivalents on the rheological, physical and chemical characteristics of yogurt. Тhe functional and technological properties of starch products of different chemical composition were studied – maltodextrin MD-10, glucose syrup IG-42 and glucose-fructose syrup GFS-42. The possibility of completely replacing dry skimmed milk and sugar in the composition of yogurt with a fat content of 1% drinkable with an equivalent content of dry substances of maltodextrin MD-10 and glucose syrup IG-42, which ensure the formation of rheological characteristics inherent high-quality yogurt. Yogurt with sucrose, which inhibits the organization of macromolecular chains of milk proteins, has the lowest thixotropic ability, and yogurt with maltodextrin MD-10 and glucose syrup IG-42 has the highest. The predominance of higher sugars in the composition of MD-10 maltodextrin lengthens, and the increased content of monosaccharides in GFS-42 accelerates the duration of fermentation of milk mixtures in the technological process of production of yogurt with a fat content of 1.0%. Monosaccharides in the composition of GFS-42 significantly affect the activity of water and at the same time reduce the moisture-retaining capacity of the sour-milk yogurt curd. The degree of influence on the rheological characteristics and moisture-binding capacity of yogurt increases with a decrease in the dextrose equivalent of starch products in the following sequence: GFS-42 → IG-42 → MD-10. So, it is the dextrose equivalent of starch products that is an objective criterion of their technological activity as part of yogurt. The results of the study will allow purposeful management of the process of forming low-fat yogurt quality indicators.

Identifying animal-derived components in camel milk and its products by ultra-high performance liquid chromatography-tandem mass spectrometry

A method for identifying specific peptide biomarkers of animal-milk-derived components in camel milk and its products was established using proteomics. Samples were prepared by defatting, protein extraction, and trypsin hydrolysis, and proteins and peptides were identified using ultra-high performance liquid chromatography-quadrupole/electrostatic orbitrap-high resolution mass spectrometry (UHPLC-Q/Exactive-HRMS) and Protein Pilot software. Twenty two peptide biomarkers from eight species (i.e., Camelus, Bos taurus, Bubalus bubalis, Bos grunniens/Bos mutus, Capra hircus, Ovis aries, Equus asinus, Equus caballus) were identified by comparing the basic local alignment search tool (BLAST) with the Uniprot database. Verification of these marker peptides were performed quantitatively using a UHPLC-triple-quadrupole mass-spectrometry (QqQ-MS) system by multiple reaction monitoring (MRM). The pretreatment method of casein in camel milk was optimized, such as defatting, protein precipitation, and re-dissolving buffer solution. The effects of various mass-spectrometry parameters, such as atomization gas, heating- and drying-gas flow rates, and desolvation-tube (DL) and ion-source-interface temperatures on ion-response intensity were optimized. Camel milk signature peptides were detected in a mixture of milk from other seven species to ensure specificity for the selected biomarker peptides. The signature peptides of seven other species were also detected in camel milk. No mutual interference between the selected biomarker peptides of the various species was observed. Adulterated camel milk and milk powder were also quantitatively studied by adding 0, 2.5%, 5%, 10%, 25%, 50%, 75%, and 100% bovine milk or goat milk to camel milk. Similarly, the same mass proportion of bovine milk powder or goat milk powder was added to camel milk powder. A quantitative standard curve for adulteration was constructed by plotting the peak areas of characteristic cow or goat peptide segments in each mixed sample against the mass percentage of the added adulterant. The adulteration standard curves exhibited good linearity, with correlation coefficients (r2) greater than 0.99. The limits of detection and quantification (LODs and LOQs, respectively) of the method were determined as three- and ten-times the signal-to-noise ratio (S/N). The minimum adulteration LODs of bovine milk and goat milk in camel milk were determined to be 0.35% and 0.49%, respectively, and the minimum LOQs were 1.20% and 1.69%, respectively. The minimum adulteration LODs of bovine milk powder and goat milk powder in camel milk powder were determined to be 0.68% and 0.73%, respectively, and the minimum LOQs were 1.65% and 2.45%, respectively. The accuracy of the adulteration quantification method was investigated by validating the quantitative detection results for 1∶1∶1 (mass ratio) mixtures of camel milk, bovine milk, and goat milk, as well as camel-milk powder, bovine milk powder, and goat-milk powder, which revealed that this method exhibits good linearity, strong anti-interference, high sensitivity, and good repeatability for adulterated liquid-milk/solid-milk-powder samples. The adulteration results for both liquid milk and milk powder are close to the theoretical values. Finally, 11 actual commercially available samples, including five camel-milk and six camel-milk-powder samples were analyzed, which revealed that only camel signature peptides were detected in 10 samples, while camel and bovine signature peptides were both detected in one camel-milk-powder sample. The ingredient list of the latter sample revealed that it contained whole milk powder from an unidentified source; therefore, we infer that the bovine signature peptides originate from the whole milk powder. These signature peptides also demonstrate the necessity and practical significance of establishing this identification method.

The impact of heat-set milk protein gel textures modified by pH on circulating amino acid appearance and gastric function in healthy female adults: a randomised controlled trial.

Modification of dairy proteins during processing impacts structural assemblies, influencing textural and nutritional properties of dairy products, and release and availability of amino acids during digestion. By modifying only pH, acid heat-set bovine dairy gels with divergent textural properties were developed to alter protein digestion. In vitro assay confirmed faster digestion of protein from a firm gel (pH 5.65) versus a soft gel (pH 6.55). We hypothesised that firm gel (FIRM-G; pH 5.6) would result in greater indispensable amino acid (IAA) appearance in circulation over 5 h and corresponding differences in gastric myoelectrical activity relative to soft gel (SOFT-G; pH 6.2). In a randomised, single-blind cross-over trial, healthy females (n = 20) consumed 150 g of each gel; plasma amino acid appearance was assessed over 5 hours. Iso-nitrogenous, iso-caloric gels were prepared from identical mixtures of bovine milk and whey protein concentrates; providing 17.7 g (FIRM-G) and 18.9 g (SOFT-G) of protein per serving. Secondary outcomes included gastric myoelectrical activity measured by body surface gastric mapping, glycaemic, triglyceridaemic, and subjective appetite and digestive responses. Overall plasma IAA (area under the curve) did not differ between gels. However, plasma IAA concentrations were higher, and increased more rapidly over time after SOFT-G compared with FIRM-G (1455 ± 53 versus 1350 ± 62 μmol L-1 at 30 min, p = 0.024). Similarly, total, branched-chain and dispensable amino acids were higher at 30 min with SOFT-G than FIRM-G (total: 3939 ± 97 versus 3702 ± 127 μmol L-1, p = 0.014; branched-chain: 677 ± 30 versus 619 ± 34 μmol L-1, p = 0.047; dispensable: 2334 ± 53 versus 2210 ± 76 μmol L-1, p = 0.032). All other measured parameters were similar between gels. Peak postprandial aminoacidaemia was higher and faster following ingestion of SOFT-G. Customised plasma amino acid appearance from dairy is achievable by altering gel coagulum structure using pH during processing and may have minimal influence on related postprandial responses, with implications for targeting food design for optimal health. The Clinical Trial Registry number is ACTRN12622001418763 (https://www.anzctr.org.au) registered November 7, 2022.

Ampiang-Dadih-a combination of Indonesian traditional fermented buffalo milk and black glutinous rice-prevents hypercholesterolemia and liver cell degeneration in vivo: A pilot study.

We aimed to evaluate the potential of Ampiang-Dadih (AD), a combination of Indonesian traditional fermented buffalo milk (Dadih) and black glutinous rice flakes (Ampiang) as an anti-hypercholesterolemic agent and to prevent liver-cell degeneration using a rat model. A mixture of black glutinous rice powder (0.3 gm/gm feed) and fermented buffalo milk (3.74/200 gm BW) was prepared to obtain AD. Fifteen adult male Sprague Dawley rats were divided into three groups of five animals each: (A) negative control group (distilled water; 5 weeks), (B) hypercholesterolemia group (1% cholesterol per feed; 5 weeks), and (C) preventive AD group (1% cholesterol and AD; 5 weeks). The blood lipid profiles were measured at weeks 2, 4, and 5. The liver enzyme activity, cholesterol level, and histology were observed at the end of week 5. AD administration simultaneously with cholesterol in Group C significantly prevented an increase in total plasma cholesterol and low-density lipoprotein levels compared to Group B. Alanine transaminase and aspartate transaminase were maintained at normal levels in Group C. Furthermore, the levels of liver cholesterol and liver cell degeneration in Group C were also maintained because of AD administration compared to that in Group B. This study demonstrated that AD has the potential to be developed as a functional food for hypercholesterolemia prevention.

МОЛОЧНАЯ СЫВОРОТКА – ЦЕННОЕ СЫРЬЕ В ТЕХНОЛОГИИ КИСЛОМОЛОЧНЫХ ПРОДУКТОВ

The integrated use of raw materials, including the processing of secondary resources, whey, can increase the efficiency of the dairy industry. The purpose of the study is to offer a fermented milk product obtained from cow’s milk and dry demineralised whey. Raw cow’s milk meets the Russian national standard GOST 31449-2013; demineralised dry whey with a 50 % demineralisation level meets GOST R 56833-2015. To obtain a fermented milk product, the necessary amount of demineralised whey was introduced into warm cow’s milk (40 °C2 °C) with constant stirring, then pasteurized (85 °С2 °С). After cooling to 40 °C2 °C, yogurt starter culture was added to the milk mixture, then the mixture was kept up to the titrated acidity of 75– 80 °T. The study established organoleptic parameters (GOST R ISO 22935-2-2011), titrated acidity (GOST R 54669-2011), viscosity of fermented milk product (GOST 9070-75), microbiological parameters (GOST 1044411-2013, GOST 32901-2014, GOST 33566-2015, GOST 33566-2015) for products with different demineralised whey content (0–6 %). As a result, yogurt containing 2 % of whey had the highest score. This product was milk-white in color, had a sour-milk taste and thick homogeneous consistency. The product energy value was calculated. The study found that 2 % demineralised whey powder increased proteins by 4 %, carbohydrates by 34.2 %, and the energy value of the product by 7.33 %. Whey is rich in biologically active substances, it boasts of antioxidant, immunomodulatory, and antitumor properties. Therefore, using whey for obtaining new food products is promising: it allows you to use health-saving technologies, solve environmental issues related to the disposal of production waste, resource conservation, secondary use of dairy raw materials.

Utilization of camel’s milk for preparation of banana, guava, persimmon, and mango ice milk

The present work was focused on application of camel's milk with banana, guava, persimmon, and zebda-mango fruits for preparation ice milk. Four ice milk treatments [TB (banana), TG (guava), TP (persimmon), and TZ (zebda-mango)] besides the first control [C* (contains cow’s milk)] and second control [C** (contains camel’s milk)] were prepared. The chemical analysis between different fruits showed noticeable differences in the total solids (TS), fat, protein, ash, crude fiber, carbohydrate, total soluble solids (TSS), pH value, radical scavenging activity (RSA), and total phenolic compounds (TPC). The physicochemical properties (especially freezing point, pH value and acidity) besides the rheological parameters of ice milk mixtures showed significant (p < 0.05) changes between controls and fruits treatments, in addition the rheological parameters (except flow behaviour index) of TG > TZ > TP > TB > C* ≈ C**. During aging times from fresh up to 4 hrs, the rheological parameters (apparent and plastic viscosities, and consistency coefficient) were increased significantly, but the yield stress and flow behaviour index were decreased significantly. The physicochemical properties of fruits ice milk treatments whether at 1 or 30 days showed significant differences between controls and fruits ice milk treatments. With regard to the RSA and TPC of ice milk treatments, the treatments were recorded significant increases in the previous parameters than controls. Through the storage periods, the significant decreases in each RSA and TPC values were reported. The melting rates of C** ≈ C* > TB > TP > TZ > TG were noticed throughout the storage periods of 1 and 30 days. Zebda-mango ice milk was ranked the best treatment according to the panelist’s judgment, followed by banana, persimmon, and then guava ice milk treatments. The total production costs showed that the TP > C** ≈ TG ≈ TZ > TB > C*, in addition the profits of C* > TB > C** ≈ TG ≈ TZ > TP, when the present treatments compared with the selling price in supermarket.

Effect of maltodextrin and inulin addition on the dairy-based powders properties

Dairy-based powders produced from the combination of concentrated milk, whey, and maltodextrin (main constituents) were used as ingredients during infant formula production. The relation between the composition of each treatment and physicochemical properties of the powders were evaluated. In work, dairy-based powders were obtained by a mixture of concentrated milk and whey. Increasing the ratio whey/milk in the mixture before drying increases the concentration of lactose into dairy based powders and reduces total protein and fat content. Besides, the addition of maltodextrin and inulin reduced powder agglomeration increased the average hydrodynamic diameter of the particles, and the theoretical glass transition temperature, exhibited strong spectral contributions to Raman spectroscopy. It was possible to infer changes in the bands by Raman spectroscopy between the formulated products, the main changes were related to the presence of lactose, maltodextrin, and inulin. Inulin is a better option than maltodextrin for drying dairy-based powders mainly because of its nutritional benefits.

Технологические свойства препаратов сычужного фермента

The quality of the finished cheese is determined by all stages of its production, but the basis of cheese making is the production of a milk clot under the action of a milk-converting enzyme. The duration of coagulation and the structural and mechanical properties of the cheese clot are critical indicators that affect the yield of cheese, consistency, pattern, taste. In practice, it is necessary to take into account that the coagulating ability of the enzyme may vary depending on the properties of the milk mixture prepared for coagulation (protein content, mineral salts, acidity, temperature). The main technological characteristics of rennet enzyme preparations (proteolytic activity, qualitative composition, sensitivity to Caions, pH, thermal stability), important for the regulation of the coagulation process, have been studied. Practical recommendations on the use of milk-clotting enzyme preparations are given.