研究了不同贮存条件、养殖场和泌乳阶段对羊奶凝乳参数的影响，采用 Formagraph 方法。

Effects of different storage conditions, the farm and the stage of lactation on renneting parameters of goat milk investigated using the Formagraph method.

机构信息

Department of Animal Biology, University of Sassari, via Vienna 2, 07100 Sassari Italy.

出版信息

J Dairy Res. 2011 Aug;78(3):343-8. doi: 10.1017/S0022029911000343.

DOI:10.1017/S0022029911000343

Abstract

This study evaluated the effect of storage on renneting properties of goat milk investigated using the Formagraph method. Milk samples from 169 goats in three farms (F1, F2 and F3) were analysed during an entire lactation (45, 75, 105, 135 and 165 days in milking DIM), to obtain renneting parameters, both from fresh milk and after storage with Bronopol and freezing at -20°C and -80°C. As regards fresh milk, mean values of clotting time were between 12·51 (45 DIM) and 13·29 min (105 DIM and F2), the curd firming time between 1·77 (45 DIM) and 2·15 min (F1) and curd firmness between 42·09 (165 DIM) and 49·55 mm (45 DIM). No statistical difference was recorded after storage. After regression analysis, all prediction models showed significance value at P<0·001 with the highest R2 value for clotting time, 0·710 (fresh vs. frozen milk at -20°C), and the lowest for clot firmness, 0·281 (fresh vs. frozen milk at -80°C). Results demonstrated that assessment of goat milk coagulation properties using the Formagraph method is also achievable after freezing or Bronopol addition.

摘要

本研究采用 Formagraph 法评估了储存对羊奶凝乳特性的影响。对来自三个农场（F1、F2 和 F3）的 169 只羊在整个泌乳期（泌乳 45、75、105、135 和 165 天）的奶样进行了分析，以获得凝乳参数，包括新鲜奶样和经 Bronopol 处理后在-20°C 和-80°C 下储存的奶样。对于新鲜奶样，凝乳时间的平均值在 12.51（45 DIM）和 13.29 分钟（105 DIM 和 F2）之间，凝乳时间在 1.77（45 DIM）和 2.15 分钟（F1）之间，凝乳硬度在 42.09（165 DIM）和 49.55 毫米（45 DIM）之间。储存后没有记录到统计学差异。回归分析后，所有预测模型的 P 值均<0.001，其中凝乳时间的 R2 值最高，为 0.710（新鲜奶与-20°C 下的冷冻奶），而凝乳硬度的 R2 值最低，为 0.281（新鲜奶与-80°C 下的冷冻奶）。结果表明，使用 Formagraph 法评估羊奶的凝固特性也可在冷冻或添加 Bronopol 后进行。