Preparation of Edible Cheese Casings With Natural Biological Characteristics From Whey Proteins and Green Tea Extract (Camellia sinensis)

Abstract

In this study, edible and biodegradable casings were manufactured from whey proteins fortified with alcoholic extract of green tea in the ratio of extraction 50% , casings of whey proteins supplemented with green tea extract at a concentration of 3% were used in the packaging of mozzarella cheese as an application of these casings and the most important results were: The superiority of the packaging model over the control sample in terms of the effectiveness of the anti-microorganism and anti-oxidation films appeared. Their effect was reflected on the packaging sample. and the moisture test was at the forefront, and the percentage of moisture was for the control sample which represents unwrapped cheese and enveloped sample which represents the added wrapped cheese Its green tea extract at a concentration of 3% after a day of manufacturing is 53.26 and 53.30%, respectively. and this percentage was decreased with significant differences on the last day(P≤0.05) between the control sample and the treated enveloped sample to 47 and 51.06%, respectively. the protein percentages gradually increased with level of insignificance in the progression of the storage period, as the control sample and treated sample after a day of manufacture were 25.30 and 25.22%, respectively. and then reached after 90 days of storage to 26.85 and 26.23% respectively, The percentage of fat with significant differences (P≤0.05) between control and treated samples increased, where it was 22.35% after a day of manufacturing, and reached 25.12 and 23.95% at the end of the storage period, respectively. The pH decreased during the storage period. and it was found that there was a development in acidity during storage and for the control and treated samples with insignificant differences(P≤0.05). The Acid value (AV) for control sample and enveloped sample was 0.13 (mEq / 100 gm fat). and the value of AV increased with significant differences in storage samples control sample and treated sample until it reached 2.0 and 1.1 (mEq / 100 gm fat), respectively. It was noted that the peroxide value increased with significant differences in control sample compared to the treated sample. where the control sample form was between 4-10 (mEq / kg) during 90 days of storage, and the treated enveloped sample was between 3.6-7 (mEq / kg).The results of total and soluble nitrogen showed an increase in the percentage of soluble nitrogen to total nitrogen for cheese and for the control and treated samples. where it was found that there were differences at a significant level of (P≤0.05) during the storage period of 90 days. The v numbers of microorganisms in mozzarella cheese were calculated in different samples to know the effect of the presence of antimicrobial growth mozzarella cheese samples coated with whey proteins with (GTE) added at a concentration of 3% (enveloped sample) were generally characterized by a lower rate of bacteria and molds contamination which represented unwrapped cheese during the 90-day storage period. As follows : As for the total number of bacteria, was decreased by 3-6 logarithmic cycles at the end of the storage period in the sample mozzarella cheese enveloped compared to the unwrapped control sample wich had significance differences. The numbers of gram-negative E.coli bacteria were decreased in the enveloped sample, by about 2 logarithmic cycles compared to mozzarella cheese in the control sample. As for the lipolytic bacteria and proteins. They were free in the samples at the beginning of the storage period, The number of lipolytic bacteria at the end of the storage period of the control sample was 3.7 x 102 cfu/g with no growth in the enveloped sample. while the number of lysed bacteria reached proteins at the end of the storage period for the control sample were 5.4 x 102 cfu/g and in the treated enveloped sample was 1.4 x 10 cfu/g . As for Staphylococcus aureus. it was observed a decrease in the rate of increase in the microbial numbers of these organisms and There were significant differences between the enveloped sample when compared to the control. As for Salmonella sp. The results indicated that the samples in which whey proteins were added to green tea extract (enveloped sample) were free of any significant growth, unlike control sample which showed clear growth at the end of the storage period. As for yeasts and molds, the enveloped sample was free of growth throughout the storage period. this shows the effect of the antimicrobial factors present in the green tea extract added to the whey proteins enveloped. while the numbers of yeasts and molds in the control sample were 8.1 x 10 2 cfu/g .at the end of the storage period. and the above results were reflected on the sensory evaluation. as the highest scores related with significant differences(P≤0.05) to the appearance, texture, taste, flavour, color, bitterness, and exotic flavors were given to the cheese samples coated with whey proteins with added green tea extract at a concentration of 3% (enveloped sample) compared to the control sample