【作者】 傅苏芳；

【导师】 刘璘；

【作者基本信息】 浙江工业大学 ， 食品科学， 2008， 硕士

【摘要】 本文研究了小麦胚芽中脂肪氧化酶酶学性质,结果表明,该酶最适反应温度为40℃,最适pH值为7.0。脂肪氧化酶在低于50℃、pH值在6～8范围内稳定,在80℃处理30min后基本失活。Mg²⁺,Ca²⁺,Cu²⁺,Fe²⁺,乙醇、丙三醇、丙酮等对该酶均有一定的抑制作用。对不同水分含量、贮藏温度、包装方式对麦胚贮藏稳定性的影响进行了研究,结果表明:水分含量,贮藏温度,包装方式对贮藏稳定性影响显著,在低水分含量（5%）或低温（4℃）或真空处理贮藏时,一个月后AV、POV、MDA指标无显著上升,分别为18.39mgKOH/goil、17.65meq/kg、0.028μmol/g;11.15mgKOH/g oil、6.70meq/kg、0.0185μmol/g。12.25mgKOH/g oil、8.04meq/kg、0.019μmol/g。分析比较了干热空气、湿蒸汽、微波、常压湿蒸汽耦合微波等稳定小麦胚芽的方法,以常压湿蒸汽耦合微波法稳定效果最好。通过响应面分析及颜色,气味等比较分析,确定了最佳参数为:水分含量为13%,常压湿蒸汽处理时间为5min,微波功率为320W,微波处理时间为3min。小麦胚芽经上述处理相对酶活力为3.7%,外观色泽理想,游离脂肪含量、水溶性蛋白质含量有所上升,同时,贮藏期间的AV、POV、MDA指标明显优于其它样,因此大大延长麦胚原料的贮藏期。更多还原

【Abstract】 Enzymatic properties of wheat germ lipoxidase were studied.The enzyme showed the optimum temperature at about 40℃,and the optimum pH is 7.0.It was stable over the pH range from 6 to 8 and below 40℃,but almost completely lost the activity by heating 80℃for 30min.The lipoxidase activity was restrained by Mg²⁺,Ca²⁺,Cu²⁺,Fe²⁺,ethanol, propanetriol,acet.The article investigated the stabilization of wheat germ with different moisture content,temperature,manner of packing in storage. The results showed that the impact of the stabilization of wheat germ was very notable.When wheat germ stored in low moisture content（5%）or low temperature（4℃）or vacuum setting,one month later,the AV、POV、MDA indication was 18.39 mgKOH/g oil、17.65 meq/kg、0.028μmol/g; 11.15 mgKOH/g oil、6.70 meq/kg、0.0185μmol/g;12.25 mgKOH/g oil、8.04 meq/kg、0.019μmol/g respectively,and have no significantly increased compared with the comparison.All varieties of methods for stabilization of wheat germ were compared,such as dry heat,steam,microwave,steam combined with microwave.Among them,steam combined with microwave produced the best result.The best parameter is that moisture content is 13%,the time of steam treatment is 5min,the power of microwave is 320W,the time of microwave treatment is 3min Using response surface methodology and analyzing the color,savor and so on.Relative activity was only 3.7%, Free fat content and water-soluble protein content were increased with above treated,meanwhile the AV、POV、MDA indication in storage time is superior to the comparison,so pretended its storage properties.更多还原