Quality Characteristics of Curd Yogurt with Sweet pumpkin

단호박 가루를 첨가한 호상요구르트의 품질 특성

Sweet Pumpkin (Cucurbita maxima) is rich in minerals, vitamins, and dietary fibers and has less fat. It is thus effective for dieting and for preventing constipation. Sweet Pumpkin contains vitamin A, particularly beta-carotene, which is turned into retinol in the body and helps protect the vision. It is currently on the spotlight as a vision care, anticancer, and diet food, among others, but because it is hard to find yogurt made of Sweet Pumpkin, in this study, Sweet Pumpkin powder was added to yogurt for promotion as a new health food. Yogurt was made with 0, 0.5, 1, 2, and 3% Sweet Pumpkin powder, and the color properties (brightness, redness, and yellowness), viscosity, pH, and acidity were measured through a sensory test (color, flavor, taste, overall acceptability). The storage stability at five-day intervals for one day, five days, ten days, 15 days, etc. was also experimented on. For the color properties, the greater the amount of Sweet Pumpkin powder added, the greater the decrease in the lightness (L) value, but the redness (a) and yellowness (b) values increased (p<0.001). For the viscosity, it was decreased for five days and then increased by 47-68% for ten days. This showed a significant difference in storage stability period: one day (p<0.001), five days (p<0.01), and ten days (p<0.01) (except 15 days). Further, there was a significant difference in pH and acidity [pH: for one day (p<0.001), five days (p<0.01), and ten days (p<0.01); acidity: one day (p<0.001), ten days (p<0.05), 15 days (p<0.001)]. No significant difference in pH was shown, however, for 15 days, and in acidity for five days. The results of the sensory test are highly estimated in the order of 1%>2%.3%>0%>0.5%. The study results indicate that the addition of 1% Sweet Pumpkin powder is most suitable for manufacturing Sweet Pumpkin yogurt.

단호박 가루 첨가량을 달리한 호상 요구르트를 개발하여 요구르트의 품질특성을 비교하였다. 단호박 가루의 첨가량 0%, 0.5%, 1%, 2%, 3%로 첨가하여 요구르트를 제조해 색도(명도, 적색도, 황색도), 점도, pH, 산도, 관능검사(색, 향, 맛, 전반적 기호도)를 측정하고 1일, 5일, 10일, 15일등 5일차 간격으로 저장성 실험을 하였다. 색도에서는 저장기간별 단호박 첨가량이 증가할수록 L값은 감소하였으나 a,b값은 증가하였다(p<0.001). 점도는 저장 5일차에서 단호박첨가군이 전체적으로 감소하였고, 저장 10일차에서 저장 5일차보다 47~68% 점도가 증가했다. 점도의 각 저장일별 단호박 첨가군에서는 저장 15일차를 제외한 저장 1일차(p<0.001), 저장 5일차(p<0.01), 저장 10일차(p<0.01)로 유의적 차이를 나타냈다. pH의 저장일별 단호박 첨가군에서 저장 1일차(p<0.001), 저장 5일차(p<0.01), 저장 10일차(p<0.01)으로 유의적 차이를 나타냈고, 산도에서는 저장 1일차(p<0.001), 저장 10일차(p<0.05), 저장 15일차(p<0.001)로 유의적 차이를 나타냈다. pH는 저장 15일차, 산도는 저장 5일차에서 첨가군 간의 유의적 차이가 없었다. 관능검사결 과 단호박가루 첨가 1%>2%>3%>0%>0.5% 군 순으로 기호도가 높게 평가되었으며, 전체적인 결과로 단호박 가루 1% 첨가군이 단호박 가루 호상요구르트 제조에서 가장 적합하다고 사료된다.