Changes in the Physicochemical Parameters of Yoghurts with Added Whey Protein in Relation to the Starter Bacteria Strains and Storage Time

The stability of the physicochemical characteristics of yoghurts during refrigerated storage is important for industry and the consumer. In this study we produced plain yoghurts with the addition of health-promoting whey protein concentrate (WPC), using two different starter cultures based on Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus. Physicochemical changes (acidity, nutritional value, water activity, water-holding capacity, texture, and colour, including whitening and yellowing indices) as well as sensory changes occurring during 28-day refrigerated storage were determined. Starter cultures were found to significantly (p ≤ 0.05 and p ≤ 0.01) influence the water-holding capacity, firmness, consistency, cohesive strength and colour parameters of the curd. Use of whey protein concentrate affected both the physicochemical and sensory quality of the yoghurts. The additive had a significant effect on potential acidity, inhibiting the increase in lactic acid in the yoghurts during storage, and also reduced syneresis. However, it decreased the lightness of curd and negatively affected its sensory characteristics, primarily flavour. Moreover, nearly all parameters changed significantly with the passage of storage time (in most cases negatively). The exceptions were total protein and fat content. The changes, however, were not severe and remained at a level acceptable to tasters. Addition of 1% or 2% whey protein to yoghurt may be a good solution that can be routinely applied in the dairy industry to offer consumers a new functional product. A comprehensive assessment of the physicochemical and sensory changes occurring during refrigerated storage of yoghurts manufactured with the addition of WPC and using different cultures is crucial for modelling such a product.

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Modifikasi Sifat Fisik Yogurt Susu Kambing dengan Penambahan Microbial Transglutaminase dan Sumber Protein Eksternal

Jurnal Aplikasi Teknologi Pangan ◽

10.17728/jatp.6396 ◽

2020 ◽

Vol 9 (2) ◽

pp. 77-82

Author(s):

Salvian Setyo Prayitno ◽

Juni Sumarmono ◽

Agustinus Hantoro Djoko Rahardjo ◽

Triana Setyawardani

Keyword(s):

Physical Properties ◽

Whey Protein ◽

Skim Milk ◽

Goat Milk ◽

Microbial Transglutaminase ◽

Water Holding Capacity ◽

Whey Protein Concentrate ◽

Protein Concentrate ◽

Protein Sources ◽

Water Holding

Penelitian ini bertujuan untuk mempelajari sifat fisik yogurt susu kambing yang dimodifikasi dengan enzim mTGase dan sumber protein eksternal. Sifat fisik yang diamati meliputi sineresis spontan (wheying-off), sineresis, water holding capacity (WHC) dan viskositas. Materi yang digunakan yaitu susu segar kambing etawah, kultur starter yogurt, enzim mTGase, susu skim bubuk, dan whey protein concentrate (WPC). Rancangan percobaan yang digunakan adalah rancangan acak lengkap dengan 4 perlakuan dan 5 kali ulangan. Perlakuan terdiri atas kontrol yaitu susu kambing segar, penambahan mTGase sebanyak 0,03% (w/w), mTGase dan susu skim 1% (w/w), mTGase dan whey protein concentrate 1% (w/w). Susu dikondisikan selama 24 jam pada refrigerator (10˚C) sebelum difermentasi menjadi yogurt. Parameter yang diuji berupa wheying-off, sineresis, water holding capacity, dan viskositas yang diukur 1 jam setelah yogurt dikeluarkan dari refrigerator. Hasil penelitian menunjukkan bahwa enzim mTGase secara signifikan menyebabkan penurunan sineresis, peningkatan WHC, dan viskositas, namun tidak menyebabkan perbedaan yang signifikan pada wheying-off yogurt. Kombinasi mTGase dan sumber protein eksternal menurunkan sineresis secara signifikan, namun tidak berpengaruh signifikan terhadap wheying-off, WHC, dan viskositas yogurt. Kombinasi mTGase + WPC 1% menghasilkan kualitas fisik yogurt yang tidak jauh berbeda dengan kombinasi mTGase + skim 1% tehadap semua parameter yang diukur. Berdasarkan hasil penelitian, dapat disimpulkan bahwa sifat fisik yogurt susu sapi dapat dimodifikasi dengan enzim mTGase saja atau kombinasi dengan sumber protein eksternal. Manfaat penelitian ini adalah memberikan informasi penggunaan enzim mTGase yang dikombinasikan dengan WPC atau susu skim 1% ternyata dapat meningkatkan kualitas fisik yogurt. Modification of Physical Properties of Goat Milk Yogurt by Addition of Microbial Transglutaminase Enzyme and External Protein SourcesAbstractThe purpose of this research was to study the modification of the physical properties of goat milk yogurt with the addition of the enzyme transglutaminase (mTGase) and external protein. The benefit of this research was to provide information on methods to improve the quality of yogurt in terms of the physical properties of yogurt. The research used fresh goat milk, dry starter culture, mTGase enzyme, skimmed milk powder, and whey protein concentrate (WPC). A completely randomized design with 4 treatments and 5 replications was used as research design. The treatments were fresh goat milk as control, fresh goat milk with 0.03% w/w mTGase, mTGase and 1% w/w skim milk, mTGase and 1% w/w whey protein concentrate. The milk was stored for 24 hours in a refrigerator (10˚C) prior to fermentation process. Wheying-off, syneresis, water holding capacity and viscosity were then measured at an hour after yogurt was removed from the refrigerator. The results showed that mTGase significantly reduced syneresis, increased WHC, and viscosity, but had no significant effect on wheying-off. The combination of mTGase + external protein sources significantly reduced syneresis, but the effect on wheying-off, WHC and yogurt were not significantly detected. The combination of mTGase + 1% WPC had similar characteristics as mTGase + 1% skim milk. In conclusion, the physical characteristics of yogurt from goat milk could be modified by mTGase enzyme or in combination with external protein sources. The use of mTGase enzyme in combination with WPC or skim milk improves the physical characteristics of yogurt.

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Improvement of physicochemical and rheological properties of kombucha fermented milk products by addition of transglutaminase and whey protein concentrate

Acta periodica technologica ◽

10.2298/apt1647011i ◽

2016 ◽

pp. 11-18 ◽

Cited By ~ 1

Author(s):

Mirela Ilicic ◽

Spasenija Milanovic ◽

Katarina Kanuric ◽

Vladimir Vukic ◽

Dajana Vukic

Keyword(s):

Rheological Properties ◽

Whey Protein ◽

Skim Milk ◽

Fermented Milk ◽

Water Holding Capacity ◽

Whey Protein Concentrate ◽

Milk Product ◽

Protein Concentrate ◽

Water Holding

The objective of this work was to investigate the effect of addition of transglutaminase (TG-0.02%, w/w) and whey protein concentrate (WPC-0.03%, w/w), on quality of kombucha fermented milk product. Samples were prepared from pasteurized semi-skim milk (0.9%, w/w fat) and kombucha inoculum (10%, v/v). The pH values were measured during the fermentation of milk (lasted until reached 4.5). Syneresis, water holding capacity and the product texture (firmness and consistency,) were assessed after production. Rheological properties of kombucha fermented milk samples were measured during ten days of storage. The sample containing TG had the lowest syneresis (21 ml), the highest water holding capacity (62%) and the highest textural characteristics (firmness - 23.99g, consistency - 626.54gs) after production. The addition of WPC to milk improved the rheological properties, while the addition of TG improved it even to a significantly greater extent after the production and during 10 days of the storage.

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Addition of pectin and whey protein concentrate minimises the generation of acid whey in Greek-style yogurt

Journal of Dairy Research ◽

10.1017/s0022029918000109 ◽

2018 ◽

Vol 85 (2) ◽

pp. 238-242 ◽

Cited By ~ 6

Author(s):

Rabin Gyawali ◽

Salam A Ibrahim

Keyword(s):

Whey Protein ◽

Production Control ◽

Dairy Industry ◽

Water Holding Capacity ◽

Whey Protein Concentrate ◽

Protein Concentrate ◽

Native Page ◽

Research Communication ◽

Acid Whey ◽

Water Holding

The objective of the study reported in this Research Communication was to investigate the effects of pectin and whey protein concentrate (WPC) on the generation of acid whey during Greek-style yogurt (GSY) processing. Yogurt samples were prepared using pectin (0·05%, w/v) and whey protein concentrate (WPC-80) (1%, w/v) as possible ingredients that reduce the acid whey production. Control yogurt sample was prepared without addition of these ingredients. The results showed that yogurt made with pectin plus WPC had significantly higher water holding capacity (~56%) than the control (33%). Similarly, yogurt supplemented with pectin plus WPC exhibited 15% less susceptibility to syneresis compared to the control (P < 0·05). Viability of L. bulgaricus and S. thermophilus in all yogurts remained ≥7·0 and ≥8·0 log CFU/g respectively. Native PAGE analysis showed an interaction between pectin and WPC. Pectin hinders the formation of large oligomeric aggregates of whey protein which correlates with an increase in WHC and a decrease in syneresis. Our results demonstrated that a combination of pectin and WPC have the potential to limit the quantity of acid whey generation in GSY manufacturing. Thus, these ingredients have positive implications for dairy industry in the production of GSY.

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FERMENTED MILK PRODUCT FOR SPORTS NUTRITION

Human Sport Medicine ◽

10.14529/hsm19s117 ◽

2019 ◽

Vol 19 (S1) ◽

pp. 128-136

Author(s):

L Zakharova ◽

I Pushmina ◽

V Pushmina ◽

M Kudriavtsev ◽

S Sitnichuk

Keyword(s):

Whey Protein ◽

Fermented Milk ◽

Sports Nutrition ◽

Starter Cultures ◽

Whey Protein Concentrate ◽

Milk Product ◽

Protein Concentrate ◽

Milk Whey ◽

Milk Whey Protein ◽

Fermented Milk Product

Aim. The article deals with the study of technological approaches to the quality and development of a functional fermented milk product for specialized sports nutrition. Materials and methods. Skim milk, whey protein concentrate, and starter cultures (DELVO-YOG®, DIRECT SET) were used for the study. Bifidobacteria (Bifidobacterium animalis) were introduced as a probiotic. Creatine monohydrate (Creatine Powder C4N9O2N3, USA) was used as an element of sports nutrition. The fruit fillers (“Green Apple”, “Blueberry”, produced by “Zuegg”, Italy) were also introduced into the product. The research was conducted using standard and original methods, mathematical modeling, and statistical processing of experimental data. Results. The obtained data on the physiological effects of proteins, fats, carbohydrates, and nutrients, enhancing the adaptive capacity to the physical and neuro-emotional stress, indicate the need for their use in the technology of specialized food for athletes. Technological approaches to the quality of a functional fermented milk product for sports nutrition were studied. Based on a combination of milk, whey protein concentrate, starter cultures, and bifidobacteria, a fermented milk product was designed. This product is intended for athletes during training, competition, and recovery. The introduction of creatine monohydrate into the milk base allowed enriching the product with amino acids. Conclusion. This study is of great interest in terms of getting yogurts with the textural properties similar to the traditional ones but with the use of functional ingredients. The study also contributes to the development of food technologies and products for sports nutrition.

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Production of Denatured Whey Protein Concentrate at Various pHfrom Wastewater of Cheese Industry

Jurnal Agritech ◽

10.22146/agritech.55439 ◽

2021 ◽

Vol 41 (2) ◽

pp. 161

Author(s):

Robi Andoyo ◽

Anindya Rahmana Fitri ◽

Ratih Siswanina Putri ◽

Efri Mardawati ◽

Bambang Nurhadi ◽

...

Keyword(s):

Heat Treatment ◽

Whey Protein ◽

Functional Properties ◽

Heat Treatment Condition ◽

Whey Protein Concentrate ◽

Protein Concentrate ◽

Cheese Industry ◽

Ph Level ◽

Water Holding ◽

Physicochemical And Functional Properties

Wastewater produced from cheese industry is rich in biological component such as whey protein, fat and lactose. Whey protein is the residual liquid of cheese making process with a high protein efficiency ratio. The wastewater source used in this study was whey liquid from cheese processing industry located at West Java, Indonesia. Conversion of soluble whey protein into whey protein microparticle is required to produce food with nutritional value that can be adjusted to the needs of the specific target with high digestibility and palatability. Whey protein was collected by separation technique through heat treatment at specific condition. This was done by changing the heat treatment condition and pH of the samples. Changing the pH of the samples before heat treatment affect the ionic strength of the whey protein hence, altering the properties of the concentrate. This study aims to produce whey protein concentrate heated at various pH level and to observe physicochemical and functional properties of the concentrates. The method used in this research was a descriptive method conducted on three treatments and two replications namely whey protein concentrate production in a pH condition 6.4; 6.65; and 7.0. The parameters observed were physicochemical and functional properties. Furthermore, the result showed that there were decrease in protein content, along with the increasing pH before heat treatment. Microstructure image (SEM) showed a finer particles with the increasing pH. Meanwhile, solubility of the rehydrated samples tends to increase along with the increasing pH. The measurement of functional properties of the samples showed that denatured whey protein produced at different pH before heat treatment have different water holding capacity and a tendency to form bonds between protein particles thereby increasing the viscosity value. These physicochemical and functional properties were suitable for denatured whey protein to be used as a texture controller in whey protein based-food production.

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Effects of pH and temperature on the water-holding capacity of casein curds and whey protein gels

Journal of Dairy Research ◽

10.1017/s0022029900031563 ◽

1996 ◽

Vol 63 (1) ◽

pp. 83-95 ◽

Cited By ~ 9

Author(s):

Cheng Tet Teo ◽

Peter A. Munro ◽

Harjinder Singh ◽

Rocky C. Hudson

Keyword(s):

Whey Protein ◽

Electrostatic Interactions ◽

Hydrophobic Interactions ◽

Mineral Acid ◽

Water Holding Capacity ◽

Whey Protein Concentrate ◽

Effects Of Ph ◽

Precipitation Ph ◽

Rennet Casein ◽

Water Holding

SummaryThe water-holding capacities of mineral acid casein (MAC) curd, rennet casein curd and whey protein concentrate (WPC) gel were determined as a function of pH and temperature by drainage of liquid on a stationary, horizontal screen. As precipitation pH was varied over the range 4·3–5·55, the water-holding capacity of MAC curd ranged from 2·4 to 5·2 g water/g dry casein with minimum water-holding capacity at precipitation pH 5·3. Samples of dried MAC curd over the same range of precipitation pH did not vary significantly in water-holding capacity, and all absorbed ∼2·0 g water/g dry casein. Both rennet casein curd and WPC (170 g total solids/kg) gels increased in water-holding capacity as the pH of the suspending liquid increased in the range 3·5–10, but the changes with pH were much smaller than for MAC curd. For both types of casein curd and for WPC gel, water-holding capacity decreased with increase in temperature in the range 5–90 °C. The results are interpreted largely in terms of changes in electrostatic interactions with pH and changes in hydrophobic interactions with temperature.

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Effect of levels of starter culture and varients of packaging materials on the quality characteristics of enriched misti dahi

Asian Journal of Dairy and Food Research ◽

10.18805/ajdfr.dr-1359 ◽

2018 ◽

Author(s):

T.C. Soumyashree ◽

M.M. Venkatesh ◽

K. Priyatam Reddy ◽

B.M. Prashanth

Keyword(s):

Whey Protein ◽

Fruit Juice ◽

Starter Culture ◽

Quality Characteristics ◽

Sensory Attributes ◽

Starter Cultures ◽

Whey Protein Concentrate ◽

Packaging Materials ◽

Protein Concentrate ◽

Qualitative Characteristics

The research was undertaken to access the effect of starter culture on the qualitative characteristics of whey protein enriched misti dahi through incorporation of whey protein concentrate @ 2.0 % whey protein concentrate and fruit juice (apple and orange - 1:1) @ 15.0 % by weight. The thermophilic starter cultures were added @ 1.0, 2.0 and 3.0 % level. Incorporation of starter culture @ 2.0 % rate yielded product having acceptable sensory attributes. Misti dahi packaged in polyethylene teraphthalate (PET) cups could be stored for longer period (i.e. 15 days) as compared to use of polystyrene, polypropylene cups or even earthen pots, when stored under refrigerated (4±2 oC) condition.

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Effect of honeydew honey addition on the water activity and water holding capacity of kefir in the context of its sensory acceptability

Scientific Reports ◽

10.1038/s41598-021-02424-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Paulina Bielska ◽

Dorota Cais-Sokolińska ◽

Joanna Teichert ◽

Jakub Biegalski ◽

Łukasz K. Kaczyński ◽

...

Keyword(s):

Water Activity ◽

Storage Time ◽

Viscosity Index ◽

Starter Cultures ◽

Water Holding Capacity ◽

Sensory Assessment ◽

Sensory Acceptability ◽

Texture Parameters ◽

Water Holding

AbstractThe aim of the research was to check how the addition of honeydew honey and various compositions of starter cultures affects the water holding capacity, water activity, color, syneresis and consistency of the obtained kefir in the context of its sensory acceptability. In this research, 2.5% and 5% (w/w) honeydew honey was added to the samples of model kefir (K) and commercial kefir (K13). Kefirs differed by the type of used starter cultures and conditions of production. The addition of honeydew honey to kefir resulted in increased water holding capacity and a reduction in water activity. Honeydew honey kefir was characterized by the following flavor: astringent, fruity, pungent and waxy. As the honey content increased, the taste and waxy flavor became sweeter. In the sensory assessment, the attributes of texture and mouthfeel, creaminess, density and firmness, do not change because of the honey amount or storage time of the samples. The use of different starter cultures in kefir production with the addition of honeydew honey impacted texture parameters, resulting in up to a 4.8-fold increased viscosity index.

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