The Effect on the Quality of Yogurt Added Water Extracted from Sea Tangle

For the purpose of making a functional and stable yogurt, new type yogurt were prepared from 12% whole milk and 2% skim milk added hot-water extracted from sea tangle. The yogurt product were evaluated for acid production(pH, titratable acidity), number of viable cell, viscosity, degree of curd sedimentation, quality-keeping property and sensory property. By addition of hot-water extracted from 0.5% sea tangle, the titratable acidity of yogurt(1.89%) was higher than that of yogurt not added hot-water extract of sea tangle(1.53%). The propagation of lactic acid bacteria was stimulated by adding hot-water extracted from 0.5% sea tangle, and the number of viable cells were about 1.4${\times}$10$\^$9/CFU/$m\ell$. On the other hand, the number of viable cells in control were 4.4${\times}$10$\^$8/CFU/$m\ell$. Viscosity of yogurt made from adding hot-water extracted from 0.5% sea tangle(25 CPS) was higher than that of yogurt with only milk(22 CPS). When yogurt made from adding hot-water extracted from sea tangle was kept at 7$^{\circ}C$ for 15 days, its quality-keeping was relatively good. The sedimentation of curd was repressed a little by adding hot-water extracted from 0.5% and 0.1% sea tangle. The overall sensory score of yogurt made from adding hot-water extracted from 1% sea tangle was the best of tested yogurt.

다시마 추출물이 요구르트 품질에 미치는 영향

요구르트의 기능성을 증가시키고 동시에 요구르트의 안정성을 높일 목적으로 다시마 열수 추출액으로부터 요구르트를 제조하여 그 품질의 특성을 조사하였다. 실험구 중 0.5% 다시마 열수 추출액으로 제조한 요구르트의 적정산도가 1.89%로, 다시마 열수 추출액 무첨가구의 적정산도 1.53%보다 높은 것으로 나타났으며, 젖산균의 생육은 다시마 열수 추출액으로 촉진되어 무첨가구의 4.4$\times$$10^{8}$ CFU/$m\ell$보다 0.5%다시마 열수 추출액 첨가구가 1.4$\times$$10^{9}$ CFU/$m\ell$로 가장 높았다. 다시마 요구르트의 점도는 0.5%의 다시마에서 25 cps로, 무첨가구의 22 cps보다 높았으나 1.0% 다시마구에서는 무첨가구의 점도와 비슷한 21.5 cps로 나타났다. 7$^{\circ}C$에서 15일간의 저장시 다시마 요구르트는 pH, 산 생성 및 생균수에 거의 변화가 없어 우수한 것으로 나타났다. 커드의 침전은 0.5% 다시마 열수 추출액으로 다소 억제시킬 수 있었으며, 관능검사에서 무첨가구에 비해 1%다시마 첨가구를 가장 선호하는 것으로 나타났다.