Manufacture Of Yogurt Research Articles

Development and functional characterization of complementary food using kodo and proso millet with acid whey from Greek yogurt processing

The Greek yogurt industry is facing challenges in terms of cost of disposal of by-product acid whey. Acid whey has health benefiting components for children and can be used in preparation of complementary food with underutilized millet species. The objective of this research was to study the effect of acid whey on the underutilized millet species (Kodo and Proso). In this study, a matrix of acid whey and millet powder was prepared ranging from 25% w/v to 100% w/v and was assessed in terms of physicochemical, antioxidant and antinutritional factors. Reduction in tannins contents were observed around 69.17% (kodo millet) and 82.8% (proso millet). For phytic acid, the decrease of 9.21% (kodo millet) was observed. Increase in total polyphenol content was observed suggesting that fermentation led to release of antioxidant and bioactive compounds, supporting that acid whey can be upcycled to develop value-added products. Novelty impact statement Acid whey generated from Greek yogurt manufacturing can be upcycled to develop value-added products by incorporating millets. Decrease in antinutritional factors, phytic acid, tannins and increase in total polyphenolic compounds were observed with millets + acid whey matrix. Analysis of functional properties indicated that mixing acid whey increased the bioavailability of the nutrients present in the millets.

Physical properties of complementary food powder obtained from upcycling of Greek yogurt acid whey with kodo and proso millets

AbstractAcid whey from Greek yogurt manufacturing currently lacks an efficient utilization system posing serious environmental problems. Millets are underutilized healthy alkaline grains that can be used for neutralizing acid whey and enabling efficient upcycling. The objective of this study was to characterize the spray‐dried powder of feed containing acid whey, kodo and proso millets. Adding millets to acid whey increased the efficiency of spray‐drying process by increasing the yield. The obtained powder was of free‐flowing character with high water solubility and dispersibility. The constructed matrix was found to have potential to be used as a shelf‐stable complementary food.Practical ApplicationsThe practical application of this paper is to provide solution to the Greek yogurt manufacturing companies to problem of improper handling and disposal of acid whey. Addition of millets to acid whey helps the spray‐drying process to generate high yield resulting in a complementary food matrix. The study was able to prove that acid whey‐millet complimentary food powder that is shelf stable and has a free‐flowing characteristics. The reconstitution properties of formulation were also found to be similar to commercial baby food powder. The produced complementary food can also help in solving the problem of undernutrition because of its potential nutritional health benefiting properties.

Preparation of Low Fat Probiotic Yoghurt Supplemented with Pomegranate Pomace Powder as Source of Antioxidant Dietary Fibers

The effect of fortification of low fat milk with pomegranate pomace powder on the chemical, rheological, antioxidant and sensory properties of low fat (1% fat) probiotic yoghurt was studied. Pomegranate pomace powder was added to low fat milk yoghurt at levels of 1, and 2%., low fat yoghurt was analyzed when fresh and during the passage of 5, 10 and 15 days of storage at the temperature of the refrigerator. The results showed that fortification of reduced-fat milk used in the manufacture of probiotic yoghurt significantly affected the chemical composition of the resulting yoghurt as it increased the contents of total solids, protein, ash, dietary fiber and phenolic , ​​ pH and viscosity values, and these increases were proportional to the supplementation ratio. While the values ​​of acidity and whey separation decreased as a supplementation ratio increased. Supplementation of reduced fat yoghurt with the pomegranate pomace powder improved the via­bility of probiotic starter culture. Low fat yoghurt containing 2% pomegranate pomace powder had the highest scores of the sensory evaluation was gained in the presence of 2% pomegranate pomace powder, compared to other low fat yoghurt treatments .Through the results, it can be recommended to fortify the low-fat milk used in the manufacture of yoghurt with pomegranate pulp powder by 2%, as this fortification improved the chemical, rheological, antioxidant and sensory properties of the resulting low-fat yoghurt.

Dynamics of Milk Material Fermentation with Whey Protein Hydrolysate

Using the whey protein hydrolysate (WPH) in yogurt manufacture contributes to the development of a number of fermenting microorganisms and accelerates the fermentation process, which would ultimately reduce production costs and the overall cost of the product. The objective of the presented study was a comparative analysis of the fermentation processes in buttermilk and skimmed milk caused by starter microorganisms in the presence of WPH. The authors were looking to create a probiotic product with typical consumer characteristics. WPH hydrolysate with a high degree of hydrolysis (DH not less than 60%) was used as a functional food ingredient to improve the nutritional value of the product. Samples of skimmed milk and buttermilk without WPH were used for control. Standard physical and chemical methods for studying the composition and indicators of dairy raw materials were applied. The titrated and active acidity were analyzed by indicator and potentiometric methods respectively. The osmotic concentration was determined with using an osmometer-cryoscope. The synthesized lactate and the degree of acid formation increase have been calculated. Qualified experts have bee detected the organoleptic evaluation of raw materials in control and experimental samples. The processes of lactic acid fermentation of skimmed milk and buttermilk both containing from 1-3 wt% of WPH and monostrain and monospecies multistrain starter microorganisms were studied. The main attention in the study was paid to the organoleptic as well as physical and chemical parameters of fermented milk clots, the characteristics of fermentation processes, and the influence of WPH on the development of microorganisms have been revealed. WPH using in the studied types of milk materials helps to increase the protein content, raise the biological value, and ensure a normalized amount of starter microbiota including probiotic bacteria. So, it has been found that using skimmed milk or buttermilk with added WPH as a basic material in the starter, probiotic cultures should be used in combination with thermophilic lactic streptococci to develop a fermented milk product for dietary prophylactic purposes.

The Effect of Adding a Large Red Chili Puree (Capsicum annuum L.) on the Physicochemical Characteristics of Yogurt

Milk is a liquid obtained from milking dairy cows, one of the processing of milk that is to be yogurt, in general yogurt is consumed as a dessert and also as an additional food such as salad dressings, generally made by adding fruit or vegetables as a dye, flavoring and also to add benefits, one of which is the addition of a large red chili puree (capsicum annuum L) where the manufacture of yogurt with the addition of large red chili puree aims as a diversification of food products and the development of processed yogurt as a complement to foods such as sauces. The research used is experimental research using a Complete Randomized Design with five treatments and 2 times the study, then analyzed physical and chemical properties (color, viscosity, pH, antioxidant capacity and total Lactic Acid Bacteria) in yogurt addition of large red chili puree with the formula of adding 2, 4, 6, 8, and 10 percent, the total percentage of addition of large red chili puree obtained from the total main raw material in the form of milk. The data of the study results in statistical tests using ANOVA and Duncan's Multiple Range Test (DMRT). The results of the analysis showed that the addition of a large red chili puree had a noticeable difference to the color, viscosity, pH, antioxidant capacity, and total LAB. Yogurt with the addition of a large red chili puree can be used as a diversification of processed yogurt products in lieu of sambal, sauces and other complementary foods that have high benefits and can be used to add to the diversity of Indonesian cuisine.

Dynamic modeling of milk acidification: an empirical approach

Acidification is an important process in the production of several dairy products and has an impact in taste, viscosity, and shelf life of the products. This paper deals with the development of an empirical mathematical model to describe milk acidification in terms of pH dynamics. The model is built upon experiments of pasteurized skimmed milk acidification for acid-induced casein precipitation and extended to predict the partitioning of calcium and phosphates in the whey and the dynamics of pH during fermentation of yoghurt manufacture. Furthermore, the model can be used directly or in optimization problems to provide recommendations about product design.

УЛУЧШЕНИЕ ОРГАНОЛЕПТИЧЕСКИХ И КАЧЕСТВЕННЫХ ХАРАКТЕРИСТИК ЙОГУРТОВ ИЗ КОЗЬЕГО МОЛОКА

Fermented milks, which are highly-consumed foods in the world and more nutritious compared to milk, have high contents of proteins, minerals and vitamins. In general, the overall properties of yogurt, such as acidity level, the production of aroma compounds as well as the sensory profile (appearance, color and texture), are important traits which have a decisive role in consumer acceptance of products. Goat milk yogurts were manufactured with the supplementation of 5% cherries, 5% blackthorn fruits, and 5% mixture of two. Yogurts were characterized based on compositional, microbiological and safety properties of the added fruit pulp and sensory analyses during storage (15 d at 5°C). Compared with control samples yogurt made by using fruits and berries had higher protein content and sensory properties, but also higher acidity values. Goat milk yogurts without additions, in particular, had better physical characteristics. Using supplements caused the changing structure of yogurt, leading to higher syneresis values. Yogurt with mixed of two fillers was the best accepted among the yogurts. For the parameters used, a mix of cherries and blackthorn has promising features as suitable ingredients for goat milk yogurt manufacture. The overall acceptability decreases when adding the non-roasted amaranth flour in a product. The main weakness of this study was the paucity of size of our panel (10 people). With a small sample size, caution must be applied, as the findings might not be transferable to show objective data.

Product differentiation and brand building: a hedonic analysis of yogurt price in China

The Chinese yogurt market has seen strong growth in recent years. To meet consumers’ diverse demand, yogurt manufacturers have invested substantially in product and brand strategies – they not only introduce new attributes to yogurt, but also create sub-brands with distinct product positioning. However, little is known regarding the effectiveness of these strategies. We fill this research gap by estimating the price premiums associated with main yogurt attributes and brands using a hedonic analysis framework. Our main findings are that plain flavored yogurt and yogurt with sugar are associated with negative price premiums while having fat, having probiotics, ambient and being designed for kids are associated with positive price premiums. Moreover, sub-brand effect plays an important role in consumer’s valuation of yogurt due to their distinct product positioning, and sub-brands that position themselves as natural, ambient, European-style, traditional style, fruits and grains, and for children have high price premium.

Effect of total solids standardization using different methods on mineral content of yoghurt

Yoghurt is a good dietary source of macro and micro minerals. However, the mineral content of yoghurt can vary according to the technological processing used in its manufacture. In this context, the aim of this study was to compare some macro (Ca, K and Mg) and micro (As, Cd, Co, Fe, Mn, Ni, Pb, Se, V and Zn) mineral contents of total solids-standardized yoghurts with four different methods by following: (1) Addition of skim milk powder to milk, (2) Concentration of yoghurt milk by vacuum evaporation, (3) Concentration of yoghurt curd in a cloth bag and (4) Concentration of yoghurt curd by mechanical centrifugation. The highest content of the macro minerals was in the yoghurt produced with method 1, while the highest content of most of the micro minerals was in the yoghurt produced with method 4. The results of this study showed that the mineral content of yoghurt could be modified by the method used in the manufacture of yoghurt to standardize total solids content.

Pegaruh Penambahan Sari Wortel Terhadap Pembuatan Yogurt ditinjau dari fisik kimia dan organoleptik

Yoghurt was one form of beverage products from milk processing that utilizes microbes in the fermentation of fresh milk into a semi-solid emulsion product with a more acidic taste. The aim of this research was to know the effect of carrot juice and optimal addition were: color, organoleptic quality (aroma, texture, color and taste), vitamin C, WHC of yoghurt. The materials used were fresh milk, carrot juice, starter plain yoghurt. The method used in this research is experimental method with Randomized Completely Block Design of 5 treatments namely the addition of carrot juice in yoghurt with concentration 0%, 10%, 15%, 20%, and 25% of milk volume (1000 ml), with each treatment was done with 4 blocks. The data analysis used variance analysis, followed by Duncan Multiple Range Test. The results showed that the addition of carrot juice 20% in the manufacture of yoghurt with different concentrations gave a very significant effect difference (P<0.01) on the lightness (L*), yellowness (b*), vitamin C and WHC as well as a real effect (P <0,05) to the redness color (a*) and not not give significant effect (P>0,05) to pH, syneresis and lactic acid bacteria. The result showed that the concentration of adding carrot juice is 20%, which results in the best quality yogurt drink with the following average values of vitamin C; 15.13%, color; 59.95 (L), 19.30 (a *), 25.85 (b *), WHC; 25% and organoleptic; 3.75 (aroma), 3.98 (color), 3.40 (taste) 4.44 (texture), pH; 4.75Keyword: carrot juice, physical quality, yoghurt

Lactic Acid and Salt Separation Using Membrane Technology.

Acid whey is a by-product of cheese and yoghurt manufacture. The protein and lactose within acid whey can be recovered using nanofiltration and electrodialysis, but this leaves a waste stream that is a mixture of salts and lactic acid. To further add value to the acid whey treatment process, the possibility of recovering this lactic acid was investigated using either low energy reverse osmosis membranes or an electrodialysis process. Partial separation between lactic acid and potassium chloride was achieved at low applied pressures and feed pH in the reverse osmosis process, as a greater permeation of potassium chloride was observed under these conditions. Furthermore, lactic acid retention was enhanced by operating at lower temperature. Partial separation between lactic acid and potassium chloride was also achieved in the electrodialysis process. However, the observed losses in lactic acid increased with the addition of sodium chloride to the feed solution. This indicates that the separation becomes more challenging as the complexity of the feed solution increases. Neither process was able to achieve sufficient separation to avoid the use of further purification processes.

Addition of inulin to probiotic yogurt: Viability of probiotic bacteria (Bifidobacterium bifidum) and sensory characteristics.

The objective of this work was to study the effect of different concentrations of inulin (0.2, 0.4, and 0.6%) on the viability of probiotic bacteria (Bifidobacterium bifidum) and sensory characteristics of probiotic yogurt. The yogurt was manufactured with Lactobacillus delbruckii ssp. bulgaricus (Lb), Streptococcus thermophilus (St), and Bifidobacterium bifidum (Bb). Raw milk was received, heated to 90°C, and divided into 4 aliquots portions. All portions were inoculated with 5.11 log cfu of Lb and St combined and 5 log cfu of Bb per kg of milk. The first portion was utilized as control (T1) while 0.2, 0.4, and 0.6% of inulin were added to the second (T2), third (T3), and fourth (T4) portions, respectively. All treatments were incubated at 40°C until a pH of 4.6 was reached. Subsequently, the yogurt was cooled and stored at 4°C for 16 days. Titratable acidity, total bacterial count (TBC), Bb count, yeast count, mold count, and sensory evaluation were determined during the storage. The results showed that the addition of inulin and the storage period have significant effects (p < .05) on the titratable acidity of the yogurt. The storage of control was ended after 8 days at 4°C due to the growth of molds on the surface of the samples. The TBC decreased (p < .05) over time in control from 8.28 to 7.97 log cfu/g. It was also decreased (p < .05) with increasing the concentration of inulin. However, the addition of inulin increased (p < .05) the viability of Bb during the storage, as well as, acted as an antimicrobial against molds in T2, T3, and T4. Additionally, there were no significant differences (p > .05) in the sensory evaluation of all treatments. We conclude that inulin can be utilized in the manufacturing of probiotic yogurt as a prebiotic, which, inturn, enhances the growth of Bb and increase the shelf‐life.

Developing yoghurts containing CLA isomers-loaded liposomes and free CLA oil

The feasibility of the addition of yoghurt with a newly developed ingredient consisting of CLA loaded liposomes was analysed. The influence of ingredient addition (at three levels: no CLA incorporation, free CLA oil or CLA-liposomes), order of thermal treatment application (before or after ingredient addition along with homogenisation by a high speed dispersion unit), and use of antioxidants (with or without tocopherols) on yoghurt manufacture was studied. CLA content, fatty acid profiles, oxidation stability, physicochemical and microbiological properties of yoghurts were evaluated. Addition of liposomal CLA or free oil did not modify the fermentation process. CLA isomers could be added before and after the thermal treatment and high CLA recoveries were found in all products. Addition of antioxidants did not influence CLA content and high oxidation stability was found. When compared with free oil addition, liposomal CLA shows a clear advantage in syneresis and improvement in the atherogenic index.

Transfer of lead from soil to pasture grass and milk near a metallurgical complex in the Peruvian Andes.

Milk quality is affected by the concentration of lead (Pb) in soil and pasture grasses used to raise cattle, especially in areas near mining-metallurgical complexes. In this study, the Pb content of soil and its transfer to grass and dairy milk in an area located to 20 km from the La Oroya Metallurgical Complex in Peru (altitude, >3,700 m s.a.l) was measured. Twenty soil samples (0–30 cm depth), 20 grass samples were collected, and 0.5 L of milk was obtained from 20 lactating cow in the communal cowshed. The Pb concentration (mg/kg) was quantified by flame atomic absorption spectrometry using a commercial Pb standard as quality control. The Pb average concentration in the soil, grass, and milk samples were 217.81 ± 39.48, 20.09 ± 2.83, and 0.58 ± 0.018 mg/kg (P < 0.01), respectively. The transfer factor (ratio of metal concentration) for Pb from soil to grass and from grass to milk was 0.095 and 0.031, respectively. The soil, grass, and milk samples all presented high Pb concentrations, with the milk samples containing 29-fold more Pb than the safety limit established by European regulations and were not suitable for human consumption or the manufacture of cheese, yogurt, and other derivatives. Our findings demonstrate that action to remediate these soils is critically needed.

Survival of &amp;lt;i&amp;gt;Lactobacillus acidophilus &amp;lt;/i&amp;gt;in Fruit-Flavored Greek Yogurt Acid Whey

Greek yogurt has become much more popular within the last 15 to 20 years. The by-product of Greek yogurt manufacture is acid whey. Although acid whey has been considered a waste product, researchers are exploring various uses of this whey. Since the health benefits of consuming probiotics are widely known, one may propose adding probiotics to acid whey to form a probiotic beverage. Typically, probiotic bacteria do not thrive in acidic conditions. It would be beneficial to determine if the probiotic Lactobacillus acidophilus can survive in these acidic conditions. The objectives were to determine the growth of L. acidophilus in acid whey resulting from manufacturing Greek yogurt and to study any changes in apparent viscosity, pH, and titratable acidity over 4 weeks of refrigerated storage. Plain yogurt was manufactured, and whey was separated from plain yogurt to yield Greek yogurt and acid whey. Acid whey was batch pasteurized, cooled, sweetened, flavored with pineapple flavoring, inoculated with L. acidophilus, and stored at 4°C for 4 weeks. The log L. acidophilus counts progressively decreased from 7.84 immediately after manufacture to 2.06 at week 4. There were no significant changes in pH and titratable acidity of the pineapple-flavored probiotic acid whey over 4 weeks of storage, indicating product stability over shelf life. Viscosity changed over the storage time with minimum values at week 2 and maximum values at week 4. Although the counts declined over 4 weeks of storage, some L. acidophilus survived in the pineapple-flavored acid whey.

INVESTIGATION OF THE RHEOLOGICAL CHARACTERISTICS AND LEVEL OF SYNTHESIS OF EXOPOLYSACCHARIDES (EPS) BY THE CONSORTIUM OF STREPTOCOCCUS SALIVARIUS SUBSP. THERMOPHILUS AND LACTOBACILLUS DELBRUECKII SUBSP. BULGARICUS AT DIFFERENT TEMPERATURE IN PROCESS OF MILK FERMENTATION

The article provides the results of studies on the influence of temperature conditions of milk fermentation in the manufacture of yogurt on the characteristics of milk clots and the level of EPS production. The characteristics of the samples of reconstituted skim milk fermented by consortia of lactic acid microorganisms for the manufacture of&#x0D; starter and viscous consistency yoghurt starter cultures under temperature conditions are determined: (43 ± 1)°С, (38 ± 1)°С, (35 ± 1)°С and ( 30 ± 1)°С. It was noted that with a decrease in the fermentation temperature from (43±1)°C to (30±1)°С, the organoleptic characteristics of the formed clot are evaluated differently. At the fermentation temperature of (30±1)°С, the lowest&#x0D; degree of syneresis was noted: 45% for the consortium, during the fermentation of milk raw materials forming clumps of inviscid consistency, 29% for the consortium, during the fermentation of&#x0D; milk raw materials forming clumps of viscous consistency. At the same time, it was found that at fermentation temperatures of (43±1)°С and (30±1)°С, the highest level of EPS synthesis for consortia was noted: (2107 ST-A+2674 TL-AV) – 874.6 and 667.9 μg / ml, (1141 ST-AV+2674 TLAV) – 683.9 and 541.3 μg / ml.

ZYOFIELD: Alat pasteurisasi fermentasi berbasis teknologi pulsed electric field sistem fuzzy logic dalam pengolahan yoghurt

Yogurt is a fresh and healthful fermented milk drink. This drink is made by a pasteurization process to eliminate pathogen bacteria in milk. The process was followed by a fermentation process with the help of Streptococcus thermophilus and Lactobacillus bulgaricus bacteria. The conventional pasteurization and fermentation process take a relatively long time, where the pasteurization process takes 15 minutes and the fermentation process takes 48 hours. In addition to the long process, the thermal pasteurization process can decrease the taste, color, and nutritional content of milk. The purpose of this research is to create a tool that can speed up the manufacture of yogurt without reducing the nutritional content of milk. ZYOFIELD is a tool that combines a Pulsed electric field (PEF) with an automatic fermentation system. PEF becomes a new method of milk pasteurization without the addition of heat, where the process temperature is 25o C so it may not reduce the important content in milk. This method utilizes an electric shock with a voltage of 20-80 kV to inactivate the pathogen bacteria within a short time of 5 minutes. ZYOFIELD is integrated with a controlled fermentation system where the fermentation temperature is maintained at 40-45° C, where at this temperature the fermentation process becomes optimum for 6 hours. The temperature on the fermentor is controlled by a fuzzy logic intelligent control system to regulate the temperature of the fermentation.

Encapsulation increases the in vitro bioaccessibility of probiotics in yoghurt

This study examined the encapsulation efficacy of probiotics in yoghurts, product physicochemical properties, the best timing to add encapsulated probiotics during yoghurt manufacturing (before or after fermentation) and their in vitro bioaccessibility. Three different yoghurt types were produced including plain and with encapsulated probiotics added before and after fermentation. A significant (P &lt; 0.05) reduction in total probiotic count was observed in yoghurts containing encapsulated probiotics after 21 days of refrigerated storage. However, the total probiotic count increased during the in vitro colonic fermentation when yoghurts containing encapsulated probiotics were used, indicating increased bioaccessibility of probiotics in the colon.

Vibrations as a cause of texture defects during yogurt manufacturing – Formation of vibrations and their propagation in dairy production lines

Abstract Vibrations during the fermentation of yogurt and related milk products have recently been reported to disturb the gelation and result in quality defects such as particle formation, graininess, and syneresis. However, primary research on this topic was focused on experiments performed on a laboratory and pilot-plant scale. In this study, three large dairy factories were visited, and yogurt samples were directly taken out of various fermentation tanks, showing great differences in terms of graininess and particle content. Thereupon, vibration measurements were conducted at three industrial yogurt plants. Particularly, pumps and their influence on the vibrational excitation of the fermentation tanks were examined. The major structural and mechanical differences of these plants, such as distances between the vibration source and the tank or the types of pumps used, led to varying vibrational states at the fermentation tanks. We concluded that the vibrational excitation of each plant must be evaluated individually in order to estimate the potential for vibration-induced texture defects.

Physicochemical properties, texture, and probiotic survivability of oat-based yogurt using aquafaba as a gelling agent.

Despite high consumer demands, the manufacture of nondairy yogurt from oat milk is currently hindered due to the lack of consistency and texture. An oat‐based yogurt was developed using oat milk and probiotics (Streptococcus thermophilus and Lactobacillus bulgaricus) with aquafaba (AF) and vegetable oil (VO) as added ingredients. Physicochemical analyses and viability of probiotics were investigated after yogurt formation and for 3 weeks under refrigerated storage. Results showed that adding AF decreased syneresis and increased water holding capacity during storage. Both AF and VO had a beneficial effect on hardness, the most important textural property of yogurt. Confocal laser scanning microscopy revealed that the added ingredients played a major role in the formation of the gel network structure of the yogurt. Both Streptococcus thermophilus and Lactobacillus bulgaricus remained at acceptable levels > 8.28 Log CFU/g and > 5.79 Log CFU/g after 3 weeks at 4°C regardless of the added ingredients.