| Proteolysis, viscosity, acid-degree, alcohol-stability, heat-stability change were studied about whole UHT milk at 37oC and 20oC , and the evaluation model of UHT milk shelf-life was established through the performance relation of every index and surplus shelf-life in two different storage temperature, (1) when the index X3 is larger than 2.5umol/mL,the model is Y = 187.733 - 10.01X1 - 90.368X3 + 0.814X4 + 2.292X5 (20oC);when the index X3 is smaller than 2.5umol/mL,the model is Y = 187.733 - 10.01X1 - 70.246X3 + 0.814X4 + 2.292X5; (2)Y = -545.39735- 16.50X3 + 5.93X4 + 2.419X5 (37oC). Among the total, Y refered to the surplus shelf-life, X1 refered to the acid-degree, X3 refered to proteolysis, X4 refered to the ratio of the milk and alcohol is 1:1 (2mL milk and 2mL alcohol), X5 refered to the ratio of the milk and alcohol is 1:2 (2mL milk and 4mL alcohol). It was found that the difference of UHT milk shelf-life influence was very significant with significant analysis at two different storage temperature. It was also found that compared with the UHT milk without LTI treatment, the shelf-life of the UHT milk was extended by 20– 30 days, which was treated by LTI treatment(55oC,15 min).The method of checking-out protein alcohol-stability was also studied in this research, It was found that the alcohol-stability is influenced greatly by pH, and compared with two kinds of method of milk and alcohol with 1:2 and 1:1, It was found that the coefficient of variation (CV) of the former was smaller than the latter, so the accuracy of alcohol-experiment was raised greatly. The method of checking-out protein heat-stability was also researched, It was found that the temperature was changed to constant temperature at 120oC is suitable.
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