A master's thesis in the Department of Food Sciences/College of Agriculture at the University of Basra examined the drying of locally produced therapeutic yogurt using different drying methods and studied its physicochemical and microbial properties during refrigerated storage.
The thesis, presented by graduate student Fatima Issa Jaafar and supervised by Professor Dr. Alaa Karim Naima and Assistant Professor Dr. Hassan Hadi Mahdi, involved the production of skimmed therapeutic yogurt using a therapeutic starter culture consisting of three types of bacteria. The yogurt was then dried using an air oven, an infrared oven, and a vacuum oven. The optimal conditions for selecting a drying method were studied based on the number of viable bacterial cells.
The thesis concluded that vacuum drying at 50°C was more efficient, as it preserved the number of live bacteria compared to other methods. Bacterial numbers gradually decreased with constant acidity and pH during storage for 90 days at 4°C. Physical and chemical tests confirmed the quality of the product.
