Preparation of Functional Probiotic Dairy Beverages fortified with Pomegranate Juice Concentrate.

Document Type : Original Article

Authors

1 Dairy Science and Technology, National Research Centre, Egypt

2 Dairy Department, Faculty of Agriculture, Damietta University, Damietta, Egypt.

3 Food Science & Technology Department, Faculty of Home Economic, Al-Azhar University, Tanta, Egypt

Abstract

The main target of this study is preparing probiotic dairy beverage or drinkable yogurt fortified with Pomegranate Juice concentrate (PJC). Quality evaluation and microbiological examination of the probiotic dairy beverages using PJC is achieved. Three ratios of PJC were used (0.8, 1.0 and 1.2%; w/w) vs. control with addition of 5% sugar to apply four treatments using cow milk. Culture contained Lactobacillus acidophilus LA-5 (A), Bifidobacterium bifidium, and Streptococcus thermophiles were used. All resultant beverages samples were stored in refrigerator at 5-7°C for 14 days and were analyzed when fresh, after 7 and 14 days of storage period. The results indicated that the pH values of the beverages fortified with PJC was decreased while the acidity was increased with supplementation of PJC and during 14 days of storage at 5-7°C. The levels of TS, WSN and Ash contents were increased as the proportion of fortification increased. Fat contents showed no clear differences between control and treatments where they contained the same ratio. The values of TN were increased as the level of PJC increased, while their values were decreased through the storage period. The TVFA levels were clearly increased as both fortification ratio and storage period increased. Microbiological examination data revealed that St. thermophiles, L. acidophilus and Bifidbacterium bifidium counts in fortified samples were decreased as PJC ratio increased and as storage period progressed rather than control. The organoleptic properties of fortified samples showed that the color & appearance degrees were low in treated samples rather than control. However, T1 and T2 possessed the favorite color in treated samples. The scores for body & texture were clear varied either in treated samples or stored samples .Flavor scores indicated that sample T2 had the favorite flavor. The total acceptability indicated that control samples had the highest degrees followed by T2.

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