방울토마토(Lycopersicon escylentnm mill ssp.)를 添加한 Yogurt의 製造에 관한 연구 = A Study on the Preparation of Yogurt Added with Tomato Juice

다국어 초록 (Multilingual Abstract)

In order to determine the effect of tomato(Lycopersicon escylentnm mill ssp.) on the yogurt quality, skim milk powders were added with tomato juice of 0%, 1%, 3%, 5% and fermented by mixed culture(Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus.
The results were summarized as follows:
1. Addition of tomato juice in skim milk decreased pH(4.3) and increased acidity(0.93%) more than control did(pH 4.6, titratable acidity 0.85%). By the addition of tomato juice, acid production was increased and pH was decreased in proportion to concentrations of tomato juices added to skim milk.
2. The number of lactic acid bacteria in yogurts added with tomato juice (4.59×10^12cfu/ml) more increased than those in control yogurt(8.96×10^11cfu/ml). By the addition of tomato juice, the number of lactic acid bacteria counts increased in proportion to concentration of tomato juices added to skim milk.
3. As fermentation time goes by, the Brix degree sugar content in skim milk were decreased more rapidly than control.
4. The pH, titratable acidity, Brix degree and lactic acid bacteria were not significantly changed for all yogurts for the storing at 5℃ for 14 days.
5. In yogurt fermentation, addition of tomato juice with glucose (1% tomato juice + 4% glucose, 3% tomato juice + 2% glucose, 5% tomato juice + 0% glucose) decreased pH and increased acidity than control(5%glucose) did. In addition of tomato juice, acidity was increased and pH was decreased in proportion to concentration of tomato juices added to skim milk.
6. In yogurt fermentation, the number of lactic acid bacteria of yogurt added with tomato juice(1% tomato juice+4% glucose, 3% tomato juice+2% glucose, 5% tomato juice+0% glucose) increased than control(5% glucose). In addition of tomato juice, the number of lactic acid bacteria increased in proportion to concentration of tomato juices added to skim milk.
7. As fermentation time goes by, the Brix degree were decreased more rapidly than control(5% glucose).
By the change of pH, titratable acidity, Brix degree and lactic acid bacteria, in yogurt fermentation, we definited that the promotive effect of tomato(Lycopersicon escylentnm mill ssp.) on the yogurt.