凝固型火龙果酸奶的制备工艺及质构特性研究

该文研究了凝固型火龙果酸奶的制备工艺，并分析其质构特性。在单因素试验的基础上，选取白砂糖添加量、乳酸菌接种量、发酵时间、发酵温度这4个因素，以感官评分为响应值，利用中心组合和响应面分析法，对火龙果酸奶的发酵工艺进行优化，得到凝固型火龙果酸奶的最佳配方为乳酸菌接种量0.27%，发酵时间7.7 h，发酵温度40 ℃，白砂糖添加量8.8%，在此条件下，得到火龙果酸奶感官评分为85.3分。使用TPA质构仪对火龙果酸奶进行测定和分析，建立质构特性与感官评分之间的线性回归模型为：Y（感官评分）= 0.076 4X1（硬度）-2.84X2（黏度）+0.772X3（内聚力）-4.36X4（弹性）+143.16。

Preparation technology and texture evaluation of set-style pitaya yogurt

The preparation technology of set-style pitaya yogurt was studied and the texture characteristics were analyzed. On the basis of single factor experiment, using sugar addition, lactic acid bacteria inoculum, fermentation temperature and time as evaluation factors, sensory evaluation score as response value, the fermentation technology was optimized by central composite design and response surface methodology. Results showed that the optimum fermentation conditions were as follows: lactic acid bacteria inoculum 0.27%, fermentation time 7.7 h, temperature 40 ℃ and sugar addition 8.8%. Under the optimal condition, the sensory evaluation score of the yogurt was 85.3. At the same time, the pitaya yogurt was measured and analyzed by TPA texture, and the linear regression model between textural properties and sensory evaluation scores was established as Y(sensory evaluation scores)=0.076 4X1(hardness)-2.84X2(adhesiveness)+0.772X3(cohesiveness) -4.36X4 (springiness) +143.16.