关键词: 高脂酸乳；营养成分；活菌数；酸度；质构特性

Abstract: In this study, to understand the differences in quality between high-fat and regular yogurts, we compared the changes in viable bacterial counts, acidity, and textural characteristics between homemade high-fat and regular yogurts as well as commercial yogurt (two samples for each type of yogurt) during the shelf life. The results showed that the fat content (16.7% and 17.0%) and energy (731 and 721 kJ/100 g) of high-fat yogurt were significantly higher than those of regular yogurt, and the carbohydrate content (3.6% and 2.3%) was significantly lower than that of regular yogurt. High-fat yogurt possessed a strong fatty flavor and a thick texture. The acidity (90.62 and 91.15 °T) and viable bacterial count (9.15 and 8.95 (lg (CFU/mL))) of high-fat yogurt were lower than those of regular yogurt, whereas the hardness (22.45 and 26.15 g), adhesiveness (0.59 and 0.72 mJ) and chewiness (0.86 and 1.03 mJ) were higher than those of regular yogurt. Compared to commercial yogurt, the acidity of homemade yogurts is more stable, but basically the same viable bacterial count and textural characteristics. In conclusion, high-fat yogurt has lower carbohydrate content, acidity and viable bacterial count, and the high fat content not only imparts a fatty flavor to this yogurt but also improves its textural properties and stability.

Key words: high-fat yogurt; nutrients; viable bacterial count; acidity; textural characteristics