【作者】 赵春燕；

【导师】 卢立新；

【作者基本信息】 江南大学 ， 包装工程， 2011， 硕士

【摘要】 奶粉是乳制品最主要的品种之一,其含有蛋白质、脂肪、糖类、维生素等多种营养物质。这些营养物质在贮藏过程中不稳定,易导致脂肪氧化、非酶褐变及维生素降解等反应。本文以婴幼儿配方奶粉为研究对象,通过对奶粉变质机理以及温度、光照和氧气浓度对其变质影响程度的研究,基于食品货架寿命预测模型理论,建立相关的影响方程,并建立各因素下基于关键质量指标的货架寿命预测模型。本课题在基于加速试验的基础上,对奶粉包装保质机理及保质期预测的研究结果如下:(1)通过对奶粉乳脂肪氧化、非酶褐变以及维生素降解机理和影响因素的研究,确定表征奶粉变质程度的指标以及测定方法,并建立了奶粉贮藏加速试验的理论与方法。(2)结合奶粉变质机理,通过在选定的不同温度下进行加速试验,研究了温度因素对奶粉非酶褐变和维生素C降解的影响,得到了表征不同温度下非酶褐变和维生素C降解速率的方程,并建立了基于奶粉非酶褐变和维生素C的保质期预测模型。(3)选用不同透光率的包装材料包装奶粉,通过恒定温湿度下,光照试验的研究,得到光照强度对奶粉相关指标的影响程度以及基于光氧化的货架寿命方程。(4)通过对奶粉包装内不同氧气浓度对其质量影响的研究,得到包装内为空气时,挥发性化合物丙醛、戊醛和己醛随储藏时间的延长,其增长速度较低氧和脱氧包装快很多,同时,维生素C降解速度明显快于其他两组。温度和氧气均影响维生素C的降解,但氧气对维生素C降解的影响更为显著。脱氧包装明显抑制了奶粉变质。更多还原

【Abstract】 Milk powder is one of the main dairy products. It contains protein, fat, sugar, vitamin, etc. During storage, these nutrients are unstable and easily cause biochemical reactions such as fat oxidation, enzymatic browning and vitamin degradation. Therefore, This paper focused on the deterioration mechanism and the influences of temperature, light and oxygen concentration for infant formula. The interrelated equations and the prediction model based on key quality indicator were obtained in accordance of prediction model theory for food shelf-life.This paper focused on researching on deterioration mechanism in milk powder and prediction method of shelf-life based on accelerated experiments. Results were as follow:(1) According to the study of fat oxidation, enzymatic browning and vitamin degradation in milk powder, indicator and method were determined and theory and method of storage accelerated testing were established.(2) Combined with deterioration mechanism in milk powder, enzymatic browning and vitamin C degradation were studied through the storage test under different temperatures and darkness. Rate of enzymatic browning and dynamic model of vitamin C degradation were obtained. Meanwhile, Shelf-life prediction model were established.(3) For milk powder packed with packaging materials of different light transmittance, during storage test under constant temperature and humidity, related indicators in milk powder were studied and equation for Shelf-life was obtained based on light intensity.(4) According to the study of milk powder packed with different oxygen concentration, the result showed propanal、pentanal and hexanal in milk powder packed with air had higher growth rate than others packed with low oxygen concentration or deoxidizing agent .Meanwhile, vitamin C degradation rate was obviously faster than the other two groups. Deoxidizer packaging for milk powder inhibited deterioration obviously.更多还原