Effect of transglutaminase-treated milk powders on the properties of skim milk yoghurt (original) (raw)
Related papers
The influence of transglutaminase treatment on functional properties of set yoghurt
International Journal of Dairy Technology, 2010
The objective of this study was to investigate the effect of transglutaminase (Tgase) on the functional properties of set yoghurt, due to enzymatic cross-linking of the milk proteins. Yoghurt samples were prepared from three formulations: reconstituted skim milk, and whole milk containing two different solid-non-fat (SNF) content, with four enzyme treatments: Control (no enzyme) and three microbial Tgase treatments: Pre-incubated 90 min, Pre-incubated and inactivated after 90 min, Not pre-incubated. The modifications which were caused by Tgase were found to be more clear when Tgase was active in set type yoghurts. It was found that nonfat yoghurt sample with lower SNF content can be produced with improved textural properties using Tgase.
Transglutaminase cross-linking of milk proteins and impact on yoghurt gel properties
International Dairy Journal, 2007
A novel yoghurt process was investigated in which milk proteins were covalently cross-linked by a microbial transglutaminase (TG) preparation containing glutathione (TG+GSH). As unheated milk is normally less reactive towards TG, TG+GSH was applied to enable non-inhibited cross-linking without requiring a pre-heat treatment beyond pasteurisation conditions. After the TG+GSH incubation phase, the enzyme was inactivated by heat treatment of the yoghurt milk prior to fermentation. During yoghurt fermentation, no negative effect of TG+GSH on fermentation time was found. Protein cross-linking by TG+GSH was enhanced, resulting in higher apparent viscosity and a higher degree of protein polymerisation than that given by TG without GSH. Furthermore, different ratios of casein to whey proteins (CWP ratios) were used to investigate the effect of both protein fractions on covalently cross-linked yoghurt gel structures. The results showed a relationship between extent of cross-linking, apparent viscosity and CWP ratio of the yoghurt gels. During storage for up to 6 weeks at 4 1C, no changes in rheological properties and degree of protein polymerisation were measurable for stirred yoghurt gels prepared from cross-linked milk proteins. r
Physical properties of yoghurt manufactured with milk whey and transglutaminase
LWT - Food Science and Technology, 2009
The effect of milk protein polymerization prior to the yoghurt fermentation process was evaluated by enzymatic reaction with microbial transglutaminase (Streptoverticillium mobaraense). Yoghurt samples were manufactured with 100% milk or by substituting milk with 20 or 30% of liquid milk whey, aimed at determining the use of natural milk whey in dairy products. Transglutaminase was added at a protein ratio of 0.5 U g À1 to all samples and evaluated regarding rheological behavior, syneresis index and texture profile. The addition of enzyme transglutaminase contributed to syneresis prevention and increased the consistency index in yoghurt samples manufactured with milk whey. Yoghurt manufactured from 70% milk plus 20% milk whey, followed by enzymatic treatment, presented similar characteristics to traditionally manufactured yoghurt (C 100), with no alteration in the syneresis of the samples (p > 0.05) and presented texture parameters similar to the control yoghurt (C 100).
Effect of Adding Transglutaminase on the Properties of Fermented Milk
Rheological, chemical and organoleptic properties of yoghurt made from (buffaloes', cows' and goats' milk) were studied by adding Microbial Transglutaminase (MTGase) at different ratios. Adding MTGase at different concentrations decrease the development of acidity, syneresis and acetaldehyde content. Also, increased the values of firmness, apparent viscosity and organoleptic properties. Buffaloes' milk yoghurt showed the highest firmness, apparent viscosity and organoleptic properties. Meanwhile it had the lowest syneresis and acidity development. Cows' milk yoghurt showed intermediate values between (buffaloes' and goats' milk yoghurt) for rheological, chemical and organoleptic properties. On the other hand, it had the lowest value of acetaldehyde (aroma compound). Goats' milk yoghurt showed the highest values of acetaldehyde, syneresis and acidity development but it had the lowest firmness and apparent viscosity.
2021
This study was done to investigate the influence of addition of Transglutaminase enzyme and whey proteins on physiochemical and sensory properties of yogurt that produced from whole cow milk where the TGase enzyme was added at a concentration of 0.15 and the whey proteins at concentrations of T1 = 1% and T2 = 2%, T3 = 3% and T4 = 4% with the manufacture of control sample C without addition. Physiochemical tests for yogurt samples included total acidity and PH while rheological tests were viscosity, syneresis and water holding capacity. The results showed a decrease in the pH values and an increase in the total acidity of the samples with storage. The results also showed an increase in the viscosity value with an increase in the concentration of whey proteins after manufacturing. The values of water holding capacity and syneresis varied by increasing the concentration of whey proteins immediately after manufacture. Also, Results showed an increase in the viscosity and syneresis value...
Physicochemical evaluation of low-fat yoghurt produced with microbial transglutaminase
Journal of the science of food and agriculture, 2018
Currently consumers demand low-fat or non-fat yoghurt but their physical properties are less attractive than those of full-fat yoghurt. It was reported that microbial transglutaminase (TG) can be used in the production of low-fat yoghurt. The aim of this work was to evaluate the effect of TG on low-fat yoghurt to improve their physicochemical and textural properties to approach to those of full-fat yoghurt. Two TG application methods (addition before fermentation or simultaneously addition with the starter), three dose levels and TG origin were evaluated. Results were compared with commercial low-fat and full-fat yoghurts. No significant differences between application methods were observed. Simultaneously addition of TG was preferred because do not require additional time-consuming steps. The best dose was 1 U TG g protein that allowed to obtain a firmness higher (4.25 N) than that of commercial low-fat (3.05 N) and full-fat (4.43 N) yoghurts. This implies that intermediate values ...
Rheological Properties of Cows milk Yoghurt Treated by Transglutaminase (TGASE)
Yoghurt was made from pasteurized, high heated (95.C/15 min.) and pasteurized milk treared with 0.2 - 0.5 g TGase/L cows milk Yoghurt was stored in the refrigerator, for l0 days and changes in pH, wheying-off, apparent viscosity and firrmness were followed at successive intervals. Also, the organoteptic properties of yoghurt from different treatments were assessed. yoghurt rnade from milk treated with TGase developed less acidity during, fermenrarion and during cold storage. on the other hand it developed less-syneresis. higher finnness, and apparent viscosity than yoghurt from untreared pasteurized milk. organoleptic scoring revealed less scores for flavour and higher scores for body and texture, for yoghurt from milk treated with TGase. However, flavour scores of yoghurt from these treatments were improved during cold storage. yoghurt of acceptable quatity can be made from pasteurized rnilk treated"with 0.4 - 0.5 g TGase/L of rnilk.
Physico-chemical properties of probiotic yoghurt produced with transglutaminase
Acta periodica technologica, 2007
The effect of different concentration of transglutaminase - TG (0.02%, 0.06% and 0.12%) on physico-chemical properties of probiotic yoghurt was investigated. Two series of yoghurt were manufactured on a laboratory scale from pasteurised skim milk (0.1 % w/w fat). Series I was produced with TGase activation during a period of 2 h at 40?C, while series II was produced without enzyme activation. Then, the adequate quantities of TGase and probiotic starter culture ABT-4 (Chr. Hansen A/S Denmark) were added. Chemical composition, physico-chemical properties (water holding capacity and whey separation) and sensory characteristics of yoghurt samples were determined after production and during 5 days of storage. Addition of TGase to milk (direct or after activation) for probiotic yoghurt manufacture improved its overall characteristics. Activation of TG in yoghurt production increases water holding capacity as well as decreases syneresis during the storage.
Acta periodica technologica, 2013
This study is concerned with the effect of concentration of transglutaminase (TG), content of milk fat and starter culture type (probiotic and kombucha) on the structure of fermented milk products. The application of TG significantly improved textural characteristics of the fermented milk products. The firmness of the samples produced from milk with 0.1g100g-1 and 0.9g100g-1 fat content with probiotic starter were by 33% and 17.6% higher, respectively, compared to the control samples. During ten days of storage, the value of the hysteresis loop area of all samples produced from milk with 0.9g100g-1 fat content with TG addition, decreased by 14%.