Yoghurt drink (doogh) is a nutritions fermented dairy product. The aim of this study was to determine the effect of TRANSGLUTAMINASE (0, 0. 025, 0. 050, 0. 075 and 0. 1%) and ziziphora essence (0. 001 and 0. 01%) on physicochemical (pH, acidity (Dornic), dry matter%, fat%, viscosity (CP), serum seperation%) and sensory properties including (taste, flavor, aroma, color, appearance, texture and overall acceptability) of yoghurt drink (doogh). The results showed that as the amounts of TRANSGLUTAMINASE and ziziphora increased, pH from 4. 05 to 4. 50, dry matter% from 5. 40 to 5. 85 and viscosity (CP) from 12. 32 to 12. 70 CP increased and acidity (Dornic) from 46 to 42. 67 and serum seperation% from 0. 87 to 0. 5 decreased. Fat content of all treatments were 1. 20%. the results for sensory evaluation showed T4 containing (0. 075 % of TRANSGLUTAMINASE ENZYME + 0. 001 % ziziphora essence) and T5 containing (0. 1% of TRANSGLUTAMINASE ENZYME + 0. 001 % ziziphora essence) had the highest sensory evaluation scores. Due to the lowest amount of serum seperation, high viscosity and the highest scores of sensory evaluations, T5 containing 0. 1% TRANSGLUTAMINASE ENZYME and 0. 001% ziziphora essence was selected as the best among others.

Kefir is a kind of dairy drink with unique and exotic flavor that is traditionally produced from fermented milk with kefir grains included a mix of bacteria and yeasts. The phase separation during storage of kefir results in an unfavorable appearance, which is known as a defect, which can be controlled by making the cross-links between the milk proteins. In this research, the addition of the microbial TRANSGLUTAMINASE ENZYME (m-TG) to diminish the syneresis and its effect on the aromatic compounds of kefir was investigated during one-month storage at a refrigerated temperature using a solid phase microextraction method combined with a gas chromatography– mass spectrometer. The results showed that the adding of the m-TG to kefir significantly affected the syneresis of kefir and caused reduce in phase separation of kefir during storage. In total, 51 volatile compositions were isolated and identified from kefir samples using SPME-GC/MS. Most of the identified compounds include acids, alcohols, ketones, esters, and aldehydes, respectively. The results indicated that the storage time significantly affected the amount of all volatile compositions, so that some volatile compounds increased, while some volatile compounds decreased during storage. The m-TG had no effect the content of the volatile constituents except for alcohols. The findings of this study revealed that the total amounts of alcoholic and acidic compounds as well as carbon dioxide were increased during storage. On the other hand, total amounts of ketones, aldehydes and esters in kefir decreased during storage. Based on the findings of this study, it could be concluded that the use of m-TG without significant effect on the properties of aromatic compounds of kefir reduces its syneresis during storage.

Introduction: The word “ probiotic” comes from the Greek word “ pro bios” meaning “ for life” , which is the opposed of the term “ antibiotics” meaning “ against life. ” Probiotics are alive bacteria and the majority of probiotic microorganisms are belonging to the genera of Lactobacillus and Bifidobacterium. Regular consumption of probiotics in the adequate amounts have many beneficial health such as prevention of diarrhea, constipation, intestinal diseases and help to digest lactose and strengthen the immune system. On the other hand, recently the use of soy products has been progressively increased due to consumer consciousness about soy benefits. Soy probiotic yogurt is of special importance due to the presence of functional compounds such as probiotic microorganisms and natural prebiotics (raffinose, stachyose), the combination which is considered and dubbed as synbiotic. Dairy products, especially probiotic yogurt, are the most common foods that are used as probiotic products. On the other hand, yogurt production and similar products have always been accompanied with problems such as defects in texture, structure and syneresis. The functionality and structure of proteins can be modified with physical, chemical and enzymatic procedures. Enzymatic modification has been recommended as a useful technique owing to high specificity of enzymatic reactions and therefore a little risk of formation of toxic products. TRANSGLUTAMINASE ENZYME can produce a gel with a desirable structure by forming covalent bonds between glutamine and lysine in protein systems. Therefore, the effect of application of TRANSGLUTAMINASE ENZYME in protein food systems (such as milk, yogurt, cheese, ice cream, bread, fish, meat and other food products) have been extensively studied by many researchers. So, the aim of this study was to evaluate the physicochemical and microbial properties of symbiotic soy yogurt as affected by TG-enzymatic treatment at different inulin concentrations. Material and methods: The effect of different amounts of TG-ENZYME (0, 0. 015, 0. 03 and 0. 045%) and inulin (0, 1 and 2%) on physicochemical (pH, acidity, syneresis) and microbial characteristics (probiotic count) of synbiotic soy yogurt during 21 days of cold storage (1, 7, 14 and 21 days) was investigated. To prepare the synbiotic soy yoghurt samples, inulin as a prebiotic and Lactobacillus acidophilus and Bifidobacterium lactis as probiotic bacteria were used and added to the soy milk. After addition of inulin, soy milk was heated (95 ° C for 5 min) and cooled to inoculation temperature ° (45 C). After the ENZYME addition, the probiotic starter culture was added and fermentation was done ° at 42 C until the pH was reached to 4. 6. Sample without TG-ENZYME and inulin was considered as control yogurt. For performing analysis, data were analyzed by a completely randomized factorial design using SPSS software, version 24. The mean of treatments was compared with Duncan test at 95% confidence level. Results and discussion: The results showed that with increasing the ENZYME concentration, amount of acidity and syneresis decreased while pH increased significantly (p<0. 001). This was probably due to formation of internal and interstitial bonds in protein network which causes reduction of bioavailability of organic compounds for microorganisms (reduce acidity) and increases water holding capacity (reduce syneresis). However, enzymatic treatment had no significant effect on total solids of the samples. Increasing the amount of inulin also caused a significant increase in acidity and total solids while expressively reduced pH and syneresis of yoghurt samples (p<0. 001). The reduction of syneresis as a consequence of inulin addition was probably due to water absorption and water holding capacity of this compound. The highest total solids was recorded for yogurt sample containing 2 percent inulin and the lowest was recorded for control (0 percent inulin). By passing the time of storage, pH and syneresis significantly decreased and acidity until the fourteenth day increased and thereafter decreased considerably (p<0. 001). However, there was no significant effect on the amount total solids. The results of microbial analysis showed that with increasing ENZYME concentration, the survival amount of Bifidobacterium lactis decreased significantly (p<0/01). Although their number in the sample containing the highest level of ENZYME was higher than standard. The formation of covalent bonds due to the addition of the TG ENZYME can remove lower the molecular weight of peptides from the available microorganisms and thus reduce their growth. On the other hand, by increasing the ENZYME concentration, unlike Bifidobacterium, the survival rate of Lactobacillus acidophilus increased significantly compared to the control sample, but eventually the amount was lower than the standard. By increasing the inulin concentration at level 2% the growth rate of Bifidobacterium lactis was significantly increased (p<0/01). The effect of storage period on the survival rate of Bifidobacterium showed that during storage, their number decreased significantly (p<0/05). However, the number of probiotic bacteria in all soy synbiotic yogurts at the end of 21-day maintenance were over 10 7 logcfu/g. Our results also showed significant interactions between three tested variables on the physicochemical characteristics and the probiotic counts. Conclusion: In general, the results of this study showed that the addition of ENZYME and inulin during storage period did not have an adverse effect on pH and acidity and also reduced the syneresis. The sample containing 0. 045% ENZYME and 2% inulin at the end of the storage period showed the least syneresis compared to the control sample. In this study, amongst two probiotic bacteria, Bifidobacterium lactis, in comparison with Lactobacillus acidophilus, was able to maintain its survival rate above the standard level. Among the different samples, the sample containing 2% inulin on the first day of storage period had the highest probiotic content. According to the results, the best synbiotic soy yogurt with acceptable probiotic count and physicochemical properties could be produced using 2% inulin and 0. 015% TG-ENZYME concentration.

The aim of this study primary was to evaluate the production possibility of high quality protein powder type A (an almost odorless and tasteless powder with a maximum fat content of 0. 75%) from milled meat of common carp through isopropanol solvent extraction method, and then the replacement of produced fish protein powder (FPP) together with the TRANSGLUTAMINASE ENZYME instead of flour in the formulation of cake and evaluation of the sensory quality, physicochemical properties and nutritional value at ambient temperature. For experiments, 1 control and 6 experimental cakes treated with 6 and 8% concentrations of fish protein powder by adding 0. 5 and 1% TRANSGLUTAMINASE levels were considered. The control treatment was free of fish protein and ENZYME powders. Factors such as fat, protein, ash and moisture content were significantly different in enriched and control treatments (P<0. 05). Peroxide value and pH increased significantly in experimental treatments containing 8% FPP in comparison with other treatments and acidity decreased significantly (P<0. 05). Sensory factors including taste, color, texture, odor, and overall acceptability of treatments contain 6% FPP and 0. 5% TRANSGLUTAMINASE ENZYME had no significant difference compared to the control sample (P>0. 05). Wih adding TRANSGLUTAMINASE ENZYME to cakes containing fish protein powder improved the physicochemical properties of the samples. With considering the results and the absence of a significant difference between samples contain 6% FPP and 0. 5% ENZYME TRANSGLUTAMINASE compared to control, this treatment can be recommended as a suitable combination for fish cake.

TRANSGLUTAMINASE is one of the ENZYMEs with transferasic activity which catalyzes the acyl transferization reaction and results in new proteins with special properties by linking proteins. In this study, the effect of this ENZYME on the properties of the veal steaks such as moisture, fat and protein content, pH, colour, tenderness and sensory properties was investigated. The results showed that the TRANSGLUTAMINASE significantly affected all mentioned properties, except pH. The moisture and fat content of the steaks decreased but the protein content increased, significantly. The colour of the ENZYME treated steaks was considerably brighter than control sample. Also, the results of tenderness showed that the TRANSGLUTAMINASE ENZYME do not affect the tenderness of the steaks (p>0.05). Generally, all ENZYME treated samples had more desirable properties than control sample and the sample with 1% ENZYME was determined as the most desirable sample (p<0.05).

Microbial TRANSGLUTAMINASE (MTGase) belongs to the transferase ENZYME family that cans formation crosslinking between glutamine amino-acid from a protein and lysine from another protein. It can be used in meat products industries for production of reprocessing meats by attaching the meat residues. In this study, MTGase used at 0.5, 1 and 1.5% for steak production from chicken meat residues and physicochemical, textural and sensorial properties of product were investigated. The results showed that MTGase reduced pH and increased shear force in MTGase-treated steaks. Cooking loss and diameter reduction after cooking were also decreased in MTGase-treated in comparison to control sample. In addition, the percentage of thickness significantly increased (P<0.5) in MTGase-treated samples. By adding ENZYME level, a* was decreased and b* increased however no significant differences was observed in L* (P>0.5) andΔE. According to the panelists, there was no significant differences between control and treatment samples for flavour and color but the mean value of texture (3.96, 4.02, 4.05 for 0.5, 1 and 1.5%) was higher in treatment samples rather than control ones (3.45). This study showed that MTGase can be used to attach the chicken meat bits for production of steak in industry.

Background and objective: Strained or concentrated yoghurt is a traditional milk product that its popularity and consumption has increased during recent years due to its higher nutritional value, longer shelf life, desirable textural and sensory properties, and today it is widely produced industrially. This product can be produced from many different animal milks such as buffalo, cow, goat, ewe and camel. The milk of various animals differs in composition and therefore this factor can affect the characteristics of the final product. Identical to the other dairy products, strained yoghurt manufactured from buffalo milk has the higher quality than those produced from cow milk due to the higher total solids and fat content; but its utilization has limited because of its higher cost. TRANSGLUTAMINASE ENZYME (TG), by createing inter- and intra-molecular cross linkages among proteins is known as an effective strategy to improve the functional properties of dairy products. TG treatment has been considered as a practical technique instead of increasing the total solids of utilized milk (by adding skim milk powder). Therefore, the aim of this study was to investigate the effect of TG ENZYME treatment on physicochemical and sensory properties of strained yoghurt prepared from cow and buffalo milk mixture and to introduce the best product with the lower buffalo milk substitution (the lower of cost). Materials and methods: Strained yoghurt samples with different amounts of buffalo milk replacement with cow (0, 25, 50, 75 and 100%, v/v) and using TG ENZYME (0 and 0.015%, w/v) were produced and 10 experimental treatments evaluated for physicochemical (pH, acidity (% lactic acid), syneresis (%) and dry matter (%)) and sensory properties (texture, colour, odour and flavour) during 21 days of storage (1, 7, 14 and 21 days) under refrigeration conditions. The obtained mean values were analyzed using a random factorial design and compared by Duncan test at 5% level.Results: The results showed that increasing the substitution amount of buffalo milk with cow milk caused a significant increase in acidity and dry matter while it expressively reduced the pH and syneresis of yoghurt samples (p<0.0001). Also, with increasing the TG ENZYME concentration, the amount of acidity and syneresis decreased and the pH increased significantly (p<0.0001), but this variable had no significant effect on dry matter (p>0.005). Over time, the pH decreased significantly and its initial value of 4.11 at the first day of storage reached to 3.98 at the end of 21 days of storage. The initial values of acidity, dry matter and syneresis as 0.98%, 20.69% and 4.45% increased till the end of storage and reached to 1.23%, 22.16% and 10.35%, respectively. In terms of sensory acceptability, increasing the concentration of ENZYME caused a significant increase in texture score of the samples (p<0.0001), while the ENZYME had no significant effect on other sensory scores of the samples. With increasing the mixing rate of buffalo milk, the texture, colour and flavour scores of the samples increased significantly (p<0.0001) and the aroma score decreased (p<0.0001). Furthermore, during the storage period, the sensory properties of the samples decreased significantly (p<0.0001).Conclusion: According to the results of this study, by replacing 75% of buffalo milk with cow milk and using TRANSGLUTAMINASE ENZYME treatment (0.015%), it is possible to produce a strained yoghurt with suitable quality characteristics.