Demineralized Whey Powder Research Articles

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.

ОЦІНКА ЕКОНОМІЧНОЇ ЕФЕКТИВНОСТІ ВПРОВАДЖЕННЯ ТЕХНОЛОГІЙ ОЗДОБЛЮВАЛЬНИХ НАПІВФАБРИКАТІВ З СИРОВАТКОЮ ДЕМІНЕРАЛІЗОВАНОЮ

The article presents the results of calculating the cost of finishing semi-finished products (sugar, marzipan, bean pastes) using demineralized whey powder; substantiation of economic efficiency and social effect of their use in restaurant business establishments. The criteria for implementation effectiveness were calculated using the regulations and costing items adopted and approved in accordance with the current legislation of Ukraine. The cost price and selling price of finishing semi-finished products with demineralized whey in accordance with the current regulations were determined by the calculation method by calculating the costs for all items. ХАРЧОВ І ТЕХНОЛОГ ІЇ 136 Випуск IІ (90), 2023 New types of finishing semi-finished products for multifunctional use with the addition of demineralized whey in a concentration of 20...50 % for sugar pastes, 20...30 % for marzipan, 10...30 % for legumes are proposed. Based on the results of calculating the cost of raw materials for their production, it was found that demineralized whey at certain concentrations can reduce the total cost of raw materials for the developed pastes by 25-40 %. The selling price decreased by 25-30% for sugar pastes, by 40-50% for marzipan pastes, and by 55-60% for legumes compared to analogs. The complex index of competitiveness of the developed pastes in relation to traditional ones is higher by 0.21-0.25 units for sugar pastes, by 0.11-0.18 units for marzipan pastes, and by 0.11-0.27 units for legumes. The analysis of the economic efficiency of the production of new types of finishing semi-finished products with demineralized whey proves the feasibility of their production. The social efficiency lies in the advantages of the developed finishing semi-finished products for confectionery over traditional ones due to their increased nutritional and biological value, reduced caloric content.

Изучение физико-химических и реологических свойств молочных систем, восстановленных с использованием кавитационной дезинтеграции

The formation of physicochemical and rheological properties of the rehydrated dairy systems «skimmed milk powder – demineralized whey powder» was studied depending on the parameters and duration of ultrasonic treatment, as well as on the percentage of replacement in solutions of skimmed milk powder with dry demineralized whey. Ternary surfaces are obtained, as well as mathematical models in the form of regression equations describing the formation of the studied properties of the reduced solutions. Optimal treatment modes were determined, as well as the percentage of replacement of skimmed milk powder with dry demineralized whey.

Исследование стабильности молочных систем, восстановленных с использованием кавитационной дезинтеграции

One of the main requirements for a rehydrated dairy system is stability throughout the entire shelf life. In samples of dairy systems «skimmed milk powder – demineralized whey powder» rehydrated using cavitation disintegration, the values of the zeta potential of dispersed phase particles, as well as the average hydrodynamic radius of casein micelles were studied in order to study the effect of ultrasound treatment modes, as well as the percentage of replacement of skimmed milk powder with dry demineralized whey in solution and their influence on the stability of the resulting system.

Effects of various milk powders on main quality parameters of cocoa butter substitute-based chocolate

Optimal conditions for formulation of cocoa butter substitute (CBS)-based milk chocolate produced in a ball mill with hydrogenated palm kernel oil stearin as CBS were defined using a D-optimal mixture design. In the formulation of chocolate samples, various amounts of whole milk powder, skimmed milk powder and demineralised whey powder were used and their effect on physico-chemical, colour, texture, and sensory properties were investigated. The fitted models demonstrated significant effects of independent variables on various quality parameters. Optimum formulation for selected parameters to maximise taste and minimise whole milk powder content as well as reduce costs were determined. Moreover, the optimum formulation was produced to validate the optimum model. Results of the validation were consistent with the findings of the model study. Furthermore, the approach used in this work could be employed to develop strategies to produce CBS-based milk chocolate with lower costs and various quality properties.

Foaming and Physicochemical Properties of Commercial Protein Ingredients Used for Infant Formula Formulation.

Protein, as one of the main ingredients for infant formula, may be closely related to the undesirable foam formed during the reconstitution of infant formula. Demineralized whey powder (D70 and D90), whey protein concentrate (WPC), and skimmed milk powder (SMP) are the four protein ingredients commonly used in infant formula formulation. The foaming and physicochemical properties of these four protein ingredients from different manufacturers were analyzed in the present study. Significant differences (p < 0.05) in foaming properties were found between the samples from different manufacturers. SMP showed a highest foaming capacity (FC) and foam stability (FS), followed by D70, D90, and WPC. Although the protein composition was similar based on reducing SDS-PAGE, the aggregates varied based on non-reducing SDS-PAGE, probably resulting in the different foaming properties. Particle size, zeta potential, and solubility of the protein ingredients were assessed. The protein structure was evaluated by circular dichroism, surface hydrophobicity, and free sulfhydryl. Pearson's correlation analysis demonstrated that FC and FS were positively correlated with random coil (0.55 and 0.74), β-turn (0.53 and 0.73), and zeta potential (0.55 and 0.51) but negatively correlated with β-strand (-0.56 and -0.71), free sulfhydryl (-0.56 and -0.63), particle size (-0.45 and -0.53), and fat content (-0.50 and -0.49). The results of this study could provide a theoretical guidance for reducing formation of foam of infant formula products during reconstitution.

E-nose, E-tongue Combined with GC-IMS to Analyze the Influence of Key Additives during Processing on the Flavor of Infant Formula.

In order to analyze the influence of key additives during processing on the flavor of infant formula, the headspace-gas chromatography-ion mobility spectrometry, electronic tongue, and electronic nose techniques were used to evaluate flavor during the processing of stage 1 infant formula milk powder (0-6 months), including the analysis of seven critical additives. A total of 41 volatile compounds were identified, involving 12 aldehydes, 11 ketones, 9 esters, 4 olefins, 2 alcohols, 2 furans, and 1 acid. The electronic nose metal oxide sensor W5S had the highest response, followed by W1S and W2S, illustrating that these three sensors had great effects on distinguishing samples. The response results of the electronic tongue showed that the three sensory attributes of bitter, salty, and umami, as well as the richness of aftertaste, were more prominent, which contributed significantly to evaluating the taste profile and distinguishing among samples. Raw milk is an essential control point in the flavor formation process of stage 1 infant formula milk powder. Demineralized whey powder is the primary source of potential off-flavor components in hydrolyzed milk protein infant formula. This study revealed the quality characteristics and flavor differences of key additives in the production process of stage 1 infant formula milk powder, which could provide theoretical guidance for the quality control and sensory improvement of the industrialized production of infant formula.

Effect of сoncentration of coconut oil with demineralised whey powder on the properties of bean pastes

There is a lack of protein products in the human diet, so balancing the nutritional composition of products remains an urgent task. The purpose of the study is to develop and determine the structural and mechanical characteristics of finishing processed products made from bean paste, demineralised whey powder, and coconut oil for confectionery. The main areas of technological use of confectionery pastes are developed: for applying to the surface of products as a layer; for creating flowers and shaped model products, as a decorative element for flour confectionery products. The study used food-grade white beans of the Mavka variety, demineralised whey powder made from whey with a 90% degree of demineralisation in accordance with TS U 15.5-00413890-089:2014. Rheological properties (resilience, elasticity, plasticity) were determined by a plane-parallel elastoplastometer of Tolstoy modification. The surface characteristics of pastes were studied using a dynamometer connected to a MiG-1.3 measuring device. The adhesive strength was determined by separating the steel plate from the bean paste. Empirical regression equations are obtained by correlation and regression analysis using the MATHCAD-14 software suite. The chemical composition of bean pastes with demineralised whey powder, their organoleptic quality indicators and structural and mechanical properties were determined to optimise the recipe composition to improve the functional and technological properties of confectionery pastes. The positive effect of the mutual use of beans and demineralised whey powder on the structural and mechanical properties of new finishing processed products was established. The improvement of the moulding capacity indicators at the concentration of 10-30% demineralised whey powder and 8% coconut oil in the composition has been proven. The reduction of stickiness in the compositions of bean pastes for modelling shaped products, coating confectionery, and making flowers as decorative confectionery products at a concentration of coconut oil up to 10% was established. Accordingly, the total scores of the developed descriptors were: 2.92 for decorative confectionery, 2.98 for coating confectionery, and 2.95 for modelling shaped products. A change in the colour intensity of bean paste compositions in the case of an increase in the concentration of demineralised whey powder is established, which allows expanding the technological methods of manufacturing shaped products. The developed technology and recipe composition allow obtaining high-quality, high-biological value, and low-calorie finishing processed products for confectionery

CRECIMIENTO Y CARACTERÍSTICAS FERMENTATIVAS DE Kluyveromyces marxianus EN MATRICES DERIVADAS DE LACTOSUERO

Milk whey has a high content of organic matter; therefore, uncontrolled discharge can cause environmental problems. An alternative for whey utilization is the production of fermented alcoholic beverages by means of the yeast Kluyveromyces marxianus, able to use lactose as a carbon source. Four different liquid growth media were prepared: whey powder (SP) and demineralized whey powder (SPD) (65 g/L) dissolved in sterilized distilled water; SPCal, similar to SP in composition, but sterilized and centrifuged to remove proteins, and milk permeate (PER). All media were fermented by 24 hours at 30°C. Samples were taken every 8 hours, for pH, biomass, ethanol and lactose determination. K. marxianus (LFIQK1 strain) growth was similar in SP, SPD and SP Cal (biomass between 2 – 3 g/L) and lower in PER. Moderate pH decline was observed, final values being between 4,7 and 5,4. Significant lactose consumption was observed in every growth media, with final values around 12 g/L and good ethanol production, especially for SP, SPD, and PER mediums (17,0±0,7; 17,6±0,5; 16,3±0,2 g/L respectively). These results are encouraging for the production of alcoholic beverages from the studied media using K. marxianus as the fermentation agent.

Evaluation of physicochemical, rheological, microstructural, and microbial characteristics of synbiotic ultrafiltrated white cheese treated with transglutaminase

The quality parameters of the optimized symbiotic ultrafiltrated white cheese (OC; containing demineralized whey powder and inulin) treated with microbial transglutaminase enzyme (MTE) was compared with two commercial probiotic (PC) and non-probiotic (NC) cheeses. The counts of probiotic (Lactobacillus acidophilus LA5) and total lactic acid bacteria, and pH were significantly decreased during the 60-day cold storage period. Fat and protein contents, stress levels at the rupture point, and Young's modulus were meaningfully increased until the 30th day of storage, and thereafter were decreased. The amount of free amino acids in OC, PC, and NC cheeses were 1,440.25, 829.02, and 616.43 μmol/L, respectively. The total amount of free fatty acids in OC, PC, and NC cheeses were 100.06, 96.79, and 90.77 mg/100 g, respectively. Results showed that OC cheese had a more compact and less porous protein structure and maintained its superior texture score until the end of the storage period. Practical applications This research article deals with improving the texture of a synbiotic ultrafiltrated Iranian white cheese using whey powder and inulin (as prebiotics) and enzymatic treatment by microbial transglutaminase. In this investigation, an optimized synbiotic cheese was produced and compared with two commercial (non-probiotic and probiotic) cheeses based on physicochemical, rheological, microstructural, and microbial characteristics of the product. We found that the optimized cheese had superior texture as compare to control cheeses. The count of probiotic bacteria in both probiotic and synbiotic cheeses throughout the storage period was more than standard (>107). Therefore, our findings may likely to be of great interest to the vision of scientists, dairy technologists, and cheese-making industries.

Development of gelatine‐based edible film by addition of whey powders with different demineralisation ratios: Physicochemical, thermal, mechanical and microstructural characteristics

The effects of using whey powders with different demineralisation rates on the physicochemical, thermal, mechanical, and microstructural properties of gelatine‐based edible films were investigated. Films were produced from film‐forming solutions (FFS) containing whey powder (WP) and 50, 70 and 90% demineralised whey powder (50DWP, 70DWP, 90DWP). The addition of whey powders increased the pH and particle size values of FFS. The zeta potential decreased significantly in the WP sample and gradually reduced depending on the demineralisation rate in the DWP samples. The addition of whey powders partially increased the density of the films. WP addition reduced the hydrophobicity of the film, while the addition of DWPs did not cause any change. The addition of whey powders decreased the L* and a* values of the films while increasing the b* values. Control was the most transparent, while 70DWP and 90DWP films had higher opacity. WP films had the most uniform and smooth surface. The highest degradation temperature (269.64 °C) was observed in the control sample. The weight loss of the control was 95%, whereas those of WP and DWP samples were 88–89%. WP addition reduced the tensile strength and increased the elasticity of the films.

Effect of grape pomace usage in chocolate spread formulation on textural, rheological and digestibility properties

In this study, dried grape (Cabernet sauvignon) pomace (DGP) as a by-product of wine production was used in the chocolate spread (CS) instead of various amounts of sugar and milk originated powders (MOP; skimmed milk and demineralized whey powder 1:1, w/w). The formulations of CS samples were determined using mixture design method. The sugar, MOP and DGP concentrations changed between 35 and 50, 0.066–8.000 and 0.23–15 g/100 g, respectively. According to the results, the consistency coefficient (K) and flow behavior index values of CS samples changed between 8.10 and 28.50 Pa.sn and 0.52–0.71, respectively. In addition, firmness and spreadability parameters were determined between 0.80-1.42 N and 2.15–4.24 N mm, respectively. Total phenolic content in CS samples ranged from 3415 to 13,754 mg GAE/kg and their digestibility ranged between 25% and 84%. Also, the digestibility of resveratrol was determined between 47.6% and 95.7% at different DGP concentrations. All of the established models successfully described the relation with R2 values higher than 0.800. Textural and rheological parameters as well as sensory characteristics of the samples indicated that DGP may be used as a healthy and low-cost ingredient in CS formulation to partially substitute sugar and MOP.

The effects of whey application on the soil biological properties and plant growth

Whey is an industrial dairy by-product. Whey proteins present in whey are valuable functional ingredients with a variety of applications. Because of high investment and management costs, many medium and small-scale cheese manufacturing plants choose the way to waste whey by discharging it to land without refining while large companies prefer to evaluate it. In this experiment were investigated the effects of whey application on some growth parameters of test plant and soil biological properties. For this purpose, greenhouse experiment was conducted to determine the effects of different whey powder solution (6% dry matter) such as no demineralized whey powder (NDWP), 50% demineralized whey powder (50% DWP) and whey protein powder (WPP) on maize growth and biological properties of soils using increasing application rates (0, 50, 100, 150 and 200 ml/kg) as three replication. At the end of the study generally, all whey treatments influenced the soil microbiological properties in comparison with the control, indicating activation by microorganisms. The addition of different doses of different whey solutions caused a rapid and significant increase in microbial biomass C, soil respiration, dehydrogenase activity and catalase activity in soil; this increase was especially noticeable in soils treated with NDWP and 50% DWP. Similarly, addition of 50% DWP to the soil increased values of plant height, fresh plant weight and fresh root weight compared to the control and other whey. Whey has a positive effect on soil biological properties. In conclusion, we can say that this waste product, which has high nutrient element content, could be used in fertilization practices especially as a nitrogen source and multi-perspective studies need to be carried out on this topic.

The effect of pre-treatment of protein ingredients for infant formula on their in vitro gastro-intestinal behaviour

Three milk products, skim milk powder (SMP), demineralised whey powder (DWP) and a whey dominant infant formula (60/40IF) and their corresponding partially hydrolysed products (SMPhyd, DWPhyd and 60/40hyd, respectively) were subjected to static infant in vitro gastro-intestinal (GI) digestion and their digesta were subsequently analysed for protein breakdown. The pre-hydrolysis of proteins provided a head-start in the gastric digestion process compared with the intact proteins, resulting in a higher proportion of small peptides (<1 kDa), a higher degree of hydrolysis and lower observable protein coagulation or curd formation in the gastric phase of the casein dominant systems in particular, which may lead to an earlier onset of gastric emptying in vivo. Little or no differences were detected during the intestinal phase. Hence pre-hydrolysis of proteins may be used as a strategy to lower gastric transit times, which may ease the gastric digestion of infant formulations.

Optimization of Microencapsulation of Human Milk Fat Substitute by Response Surface Methodology

Human milk fat substitutes (HMFS) are rich in polyunsaturated fatty acids which upon microencapsulation, can be used as a source of high quality lipids in infant formula. The response surface methodology (RSM) was employed to optimize the microencapsulation condition of HMFS as a functional product. The microencapsulation efficiency (MEE) of microencapsulated HMFS was investigated with respect to four variables including concentration of soy lecithin (A), ratio of demineralized whey powder to malt dextrin (B), HFMS concentration (C), and homogenizing pressure (D). The optimum conditions for efficient microencapsulation of HMFS by the spray drying technique were determined as follows: the amount of soybean lecithin-0.96%, ratio of desalted whey powder to malt dextrin-2.04:1, oil content-17.37% and homogeneous pressure-0.46MPa. Under these conditions, the MEE was 84.72%, and the basic indices of the microcapsules were good. The structure of the microcapsules, as observed by scanning electron microscopy (SEM), revealed spherical, smooth-surfaced capsules with diameters ranging between 10-50 μm. Compared with HFMS, the peroxide value (POV) and acid value (AV) of the microcapsule were significantly lower during storage indicating that the microencapsulation process increases stability and shelf life. Infrared spectroscopic analyses indicated that HFMS had the same characteristic functional groups as the oil extracted from microcapsules. Simulated in vitro digestion revealed that the microcapsules were digested completely within 2h with maximum lipid absorption rate of 64%. Furthermore, these results advocate the embedding process of HFMS by RSM due to its efficacy.

Use of whey powder and skim milk powder for the production of fermented cream

This study is about the production of fermented cream samples having 18% fat by addition of starter cultures. In order to partialy increase non-fat solid content of fermented cream samples, skim milk powder and demineralized whey powder in two different rates (50% and 70%) were used. Samples were analyzed for changes in their biochemical and physicochemical properties (total solid, ash, fat, titratable acidity, pH value, total nitrogen, viscosity, tyrosine, acid number, peroxide and diacetyl values) during 29-day of storage period. Samples tested consisted of 7 different groups; control group (without adding any powder), skim milk powder, 50% demineralized whey powder and 70% demineralized whey powder samples were in two different addition rate (2% and 4%). Also samples were analyzed for sensory properties. According to the results obtained, the addition of milk powder products affected titratable acidity and tyrosine values of fermented cream samples. Although powder addition and/or storage period didn’t cause significant variations in total solid, ash, fat, pH value, viscosity, acid number, peroxide, tyrosine and diacetyl values; sensory properties of fermented cream samples were influenced by both powder addition and storage period. Fermented cream containing 2% skim milk powder gets the top score of sensory evaluation among the samples.

INVESTIGATION OF RHEOLOGICAL CHARACTERISTICS OF CONCENTRATED MILK PRODUCTS WITH A COMPLEX CARBOHYDRATE AND PROTEIN COMPOSITION

Abstract: When developing new types of dairy products, the formulation of which includes components of both dairy and nondairy origin, it is necessary to study the rheological characteristics of these products. The paper studies the rheological characteristics of concentrated milk products with a complex carbohydrate and protein composition. The study was conducted at the premises of FSBEI HPE State Dairy Farming Academy named after N.V. Vereshchagin (Russia, Vologda Region, Vologda). By using the rotary viscometer Reotest 2.1 the dependence of shear stress (τ, Pa) and effective viscosity (ηef) on shear rate (γ, s-1) was determined. Freshly made product samples were studied, as well as product samples in the process of storage. In the course of the processing of the obtained data, it was found that freshly made concentrated milk products with sugar, as well as the same products in the process of storage during a period of up to 3 months are classified as liquids, by virtue of the fact that the dependence of shear stress on shear rate for these samples has a linear character. It is recommended to use a Hoppler viscometer for the measurement of viscosity in these samples. Adding starch syrup, malt, or demineralized whey powder to the products results in the deviation of their rheological characteristics from the properties of liquids. The dependence of shear stress on shear rate for these product samples follows a power-law relationship. On this basis it can be concluded that these products are classified as pseudoplastic bodies. During prolonged storage, consolidation of the structure and an increasing degree of deviation from the properties of Newtonian liquids was observed in all studied samples. This behavior is attributable to the formation of filamentary bridges between the casein micelles, which takes place in the microstructure of concentrated milk products with a complex carbohydrate and protein composition after long storage. These bridges are pseudo-polymers, formed by glucose monomers, and determine the microstructure of the product, its organoleptic and rheological properties. It is recommended to measure the viscosity of the developed products using a rotary viscometer.

Production of Antilisterial Bacteriocins from Lactic Acid Bacteria in Dairy-Based Media: A Comparative Study.

One hundred and eight strains of lactic acid bacteria (LAB) were screened for bacteriocin production by the modified deferred antagonism and agar well diffusion methods. When the modified deferred antagonism method was employed, 82 LAB strains showed inhibitory action against Listeria monocytogenes v7 ½a, whereas 26 LAB strains expressed no inhibition. Only 12 LAB strains exhibited inhibitory activity when the agar well diffusion method was used, 11 of which had been previously recognized as bacteriocin production positive (Bac(+)). Lactobacillus viridescens NRRL B-1951 was determined, for the first time, to produce an inhibitory compound with a proteinaceous nature. The inhibitory activity was observed in the presence of lipase, α-chymotrypsin, and trypsin, but no inhibition zone could be detected in the presence of proteinase K, indicating the proteinaceous nature of the inhibitory compound. The inhibitory compound was active against Lact. sake ATCC 15521 and Lact. plantarum NCDO 995. Bacteriocin production by the Bac(+) LAB strains was assessed in Lactobacillus MRS Broth as well as in dairy-based media such as nonfat milk, demineralized whey powder, and cheddar cheese whey supplemented with complex nutrient sources that are rich in nitrogen. Lact. sake ATCC 15521 and L. monocytogenes CWD 1002, CWD 1092, CWD 1157, CWD 1198, and v7 ½a were used as indicators. The inhibitory activities of the bacteriocins varied depending on the indicator strains and the growth media used. The LAB indicator strains were found to be more sensitive to inhibition by bacteriocins when compared to the listerial indicator strains. Among the listerial indicators, L. monocytogenes CWD 1002 and CWD 1198 were the most sensitive strains to the bacteriocins investigated in this study. Media composition had a significant influence on bacteriocin production and activity. When compared to demineralized whey powder medium and cheddar cheese whey medium supplemented with whey protein concentrate, cheddar cheese whey medium supplemented with complex nutrient sources such as yeast extract, polypeptone, proteose peptone nr. 3, or soytone appeared to be more supportive of bacteriocin production.

An investigation of the volatile compound profiles of probiotic yogurts produced using different inulin and demineralised whey powder combinations

Volatile compound profiles of probiotic yogurt samples prepared using 8 different prebiotic combinations were analyzed using gas chromatography/mass spectrometry (GC-MS) with solid phase micro extraction during 28 days of storage. A total of 40 volatile compounds were identified in yogurt samples during storage consisting of 2 aldehydes, 6 ketones, 4 alcohols, 6 acids, 5 esters, 3 terpenes, 3 aromatic hydrocarbons, and 12 aliphatic hydro-carbons. Acetaldehyde, diacetyl, acetoin, 2-heptanone, ethanol, isoamyl alcohol, acetic acid, caproic acid, caprilic acid, and capric acid were the major volatile compounds in all probiotic yogurt samples.

Study of Thermal Behaviour of Milk Protein Products Using a Chemometric Approach

This study deals with the evaluation of the behavior of viscosity evolution of the Milk Protein Products (MPPs) solutions in different concentrations used in different conditions of thermal processing by means of Rapid Visco Analyzer (RVA). Skimmed milk powder (SMP), whey protein Original Research Article Stephani et al.; BJAST, 7(1): 62-83, 2015; Article no.BJAST.2015.126 63 concentrate (WPC), milk protein concentrate (MPC), whey powder (WP) and demineralized whey powder (DWP) were analyzed; the evaluated solid-liquid ratio solutions were 0.1 g∙g -1 to 0.45 g∙g -1 of dry solids in water (DSW) for the MPC, 0.1 g∙g -1 to 0.4 g∙g -1 of DSW for the WPC and 0.5 g∙g -1 to 0.8 g∙g -1 of DSW for SMP, WP and DWP. Brazilian industrial heat treatment set ups were used, with temperatures ranging from 65°C to 95°C and retention time from 5 to 30 minutes. The results were interpreted according to the viscosities during heating and cooling, being possible to optimize the MPPs different parameters conditions with the interpretations of the viscographic profiles based on the thermal behavior of proteins, especially for the SMP, MPC and WPC. The data showed similarity in viscographic characteristics of the solutions when evaluated at 65°C for 30 minutes, at 85°C for 15 minutes and 95°C for 5 minutes, for the MPC and WPC at 95°C for 5 minutes, all of them for different concentrations of proteins in water.