Pasteurization Effects on Drinking Yogurt Quality Containing Aloe Vera Gel Extract and Strawberry Pulp
Iqra Razaq, and Nuzhat Huma
ABSTRACT: Popularity of drinking yogurts is increasing due to significant health benefits, on the go lifestyle and unique valuable ingredients. For the production of drinking yogurt, the present study was being carried out. Effect of various times and temperatures of pasteurization was studied in respect of stability of the product as well as concentration of Aloe Vera gel extract and strawberry pulp was being optimized. A varying heating times and different temperatures of pasteurization (70oC, 80oC, 90oC and 100oC for 5 and 10 minutes) were used in this process. With the storage at refrigeration temperature, evaluation of product for various attributes was carried out including physicochemical (pH, total solids, acidity and viscosity), microbiological (total plate count) and sensory. Effect of storage, time and temperature was seen on yogurt pH that decreased during storage while DY100/10 showed minimum decrease (0.39). Whereas, significant increase was observed in acidity during storage, as DY100/10 showed minimum increase (0.17) while reduction in viscosity was observed and DY100/10 showed minimum reduction (46.33). DY70/5 showed the maximum reduction in viscosity (50) and highest increase in acidity (0.22). During storage, nonsignificant increase in total solids was seen while DY100/10 showed maximum increase (0.3). Increase in storage time led to the decrease in number of total plate count and the sensory attributes (appearance, flavor, sensory acidity, body and texture) were affected significantly. During 20 days of storage, maximum scores were awarded to DY100/10 while minimum scores were obtained by DY70/5. From the present investigation it can be concluded that the best drinking yogurt with respect to shelf life and its sensory acceptance is DY100/10 with a storage period of 20 days.