不同热处理工艺对牛乳中5种活性物质的影响

Effects of Different Heat Treatment Processes on Five Active Substances in Milk

[目的]牛乳作为营养价值丰富的天然动物蛋白来源,除富含钙、蛋白质等营养素,还含有丰富的生物活性物质,包括免疫球蛋白、乳铁蛋白、α-乳白蛋白、β-乳球蛋白及乳过氧化物酶等。[方法]研究6种不同温度时间组合的不同热处理方式,对牛乳中活性物质的影响。[结果]活性物质含量随热处理强度提升而降低;耐热性最差的是乳过氧化物酶,在80℃/15 s热处理条件下全部失活;耐热性最强的是α-乳白蛋白,即使在137℃/4 s最高强度热处理条件下,仍具有25%的保留率;且85℃/15 s热处理强度下,α-乳白蛋白保留率不低于90%,而乳铁蛋白、免疫球蛋白G保留率不足5%,乳过氧化物酶几乎完全失活;5种活性物质对温度的敏感性顺序:乳过氧化物酶>乳铁蛋白>免疫球蛋白G>β-乳球蛋白>α-乳白蛋白。[结论]对不同温度时间组合热处理乳的几种活性物质指标检测结果表明,不同热处理工艺对活性物质保留有明显影响。为企业选择适宜的热处理工艺、生产活性成分不同的系列产品,提供理论依据和数据支撑。

[Objective]Milk,as a natural source of animal protein with rich nutritional value,is rich in calcium,protein and other nutrients,but also contains rich biological active substances,including immunoglobulin,lactoferrin,α-lactobumin,β-lactoglobulin and lactoperoxidase.[Method]The effects of six different heat treatments with different temperature and time combinations on the active substances in milk were studied.[Result]The content of active substance decreased with the increase of heat treatment intensity.The lactoperoxidase with the worst heat resistance was completely inactivated at 80℃/15 s.The highest heat resistance isα-lacubumin,which has a retention rate of 25%even at the highest heat treatment at 137℃/4 s.Under the heat treatment intensity of 85℃/15 s,the retention rate ofα-lactoalbumin is not less than 90%,but the retention rate of lactoferrin and immunoglobulin G is less than 5%,and the lactoperoxidase is almost completely inactivated.The temperature sensitivity of the five active substances was as follows:lactoperoxidase>lactoferrin>immunoglobulin G>β-lactoglobulin>α-lactobumin.[Conclusion]The test results of several active substances in the combined heat treatment emulsion at different temperature and time showed that different heat treatment processes had obvious influence on the retention of active substances.The research results of this paper provide theoretical basis and data support for enterprises to choose the appropriate heat treatment process to produce series of products with different active ingredients.