喷雾干燥杨梅粉玻璃化转变温度和结块特性研究

Studies on Glass Transition Temperature and Caking Properties of Spray-Dried Bayberry Powder

杨梅粉在加工和贮藏过程中很容易结块而使品质变差,为避免和减轻其结块,本实验采用差示扫描量热仪研究了杨梅粉不同水分活度与其玻璃化转变温度(Tg)之间的关系,温度湿度对杨梅粉结块的影响等,结果表明杨梅粉水分活度(Aw)与Tg呈线性关系,Tg=45.758-168.8 Aw(R2=0.863 1);杨梅粉在加工过程中,尽可能使环境温度低于15℃,相对湿度低于22%;杨梅粉结块过程中经历粉的塌陷,粘结,最终导致结块.

Bayberry powder is easy to cake leading to the bad quality during the processing and storage. In order to avoid and lighten caking, the followed experiments were carried out, such as the correlation between water activity and glass transition temperature by differential scanning calorimetry （DSC） and the effects of temperature and relative humidity on caking of bayberry powder. Glass transition temperature of bayberry powder had linear correlation with the water activity, T g= 45. 758 -168.8 aw （R2 = 0. 863 1 ） The appropriate processing temperature and relative humidity of bayberry powder should be lower than 25 ℃ and 22% , respectively. Collapse, stikiness, and caking were the three steps of bayberry powder caking.