The Preparation of Fermented Milk from Milk and Fruit Juices

우유와 과즙을 이용한 발효유의 제조

  • Ko, Young-Tae (Department of Foods and Nutrition, Duksung Women's University) ;
  • Kang, Jung-Hwa (Department of Foods and Nutrition, Duksung Women's University)
  • 고영태 (덕성여자대학교 식품영양학과) ;
  • 강정화 (덕성여자대학교 식품영양학과)
  • Published : 1997.12.01

Abstract

Gel-type fermented milk was prepared from milk or mixture of milk and apple juice/grape juice. Acid production (pH change) and growth of Lactobacillus acidophilus (KCTC 2182) were studied. The effects of juice addition on sensory property of fermented milk were also studied. The pH value of samples containing mixture of milk and apple juice/grape juice (25 mL : 25 mL to 5 mL : 45 mL) was lower than that of milk sample. However, number of viable cells of L. acidophilus at 21 hr in milk and samples containing juices was similar. During lactic fermentation for 24 hr, pH of all samples dropped significantly between 6 hr and 21 hr. pH values of mixture of milk and juices were lower than that of milk sample. Growth curve showed that lag phase continued to approximately 3 hr and log phase continued to approximately 15 hr in all samples. Number of viable cells in all samples was similar Sensory evaluation showed that overall acceptability of fermented milk prepared from apple juice/grape juice and milk (15 mL : 35 mL or 5 mL : 45 mL) was better than that of reference sample. The optimum ratio of mixture of juice and milk was 15 mL : 35 mL. The score values of sensory test of fermented milk prepared from mixture of grape juice and milk were slightly higher than those of mixture of apple juice and milk.

Keywords

fermented milk;Lactobacillus;apple juice;grape juice