摘要
对揉捻叶在20、30、40℃及不同的水分活度(0.11—0.98)下的解吸和吸附特性进行了研究,结果表明,揉捻叶的等温解吸和吸附曲线符合 Halsey 方程,解吸和吸附过程存在着滞后现象。在相同的水分活度下(等压线),温度升高,平衡含水率下降;在相同的平衡含水率下(等量线),温度升高,相对湿度则降低。同时,解吸和吸附过程中的焓随含水率的下降而增加。此外,温度和相对湿度对解吸和吸附速率有明显的影响。本文还对揉捻叶的解吸和吸附特性与茶叶品质及花茶窨制技术的关系进行了讨论。
The properties of moisture desorption and adsorption for rolled leaves ofgreen tea were studied under different temperatures(20,30,40℃)anddifferent water activities(0.11—0.98).Results showed that the desorptionand adsorption isotherm pattern for rolled leaves were suitably expressed byHalsey equation.The desorption and adsorption process existed hysteresisphenomenon.Under the same Aw(isobar),equilibrum moisture content(EMC)decreased when the temperature increased.The relative humiditybecame lower as the temperature rised on the same equilibrium moisturecontent(isopleth).Enthalpy of desorption and adsorption process incr-eased as EMC decreased.The effects of temperature and relative humidityon the rate of desorption or adsorption were significant.The relation ofthe properties of desorption and adsorption to tea quality and scented teatechnique were also disscussed in this paper.
出处
《茶叶科学》
CAS
CSCD
1992年第2期151-158,共8页
Journal of Tea Science
基金
国家自然科学基金
关键词
揉捻叶
解吸
吸附
平衡含水率
水分活度
Rolled leaves
Desorption
Adsorption
Equilibrium moisture content
Water activity
