含水量不同的原料加工普洱熟茶品质差异的研究

以日光干燥至不同含水量的晒青茶为原料,按常规后发酵工艺加工普洱熟茶,并对其进行品质差异分析.感官审评结果表明,含水量为26.9 %的原料加工成的普洱熟茶(处理2)与含水量为11.6 %的原料加工成的普洱熟茶(对照)品质相似,均优于含水量为43.5 %的原料加工成的普洱熟茶(处理1).理化成分分析结果显示,在渥堆过程中茶多酚、氨基酸、咖啡碱、水浸出物、茶黄素、茶红素、茶褐素、水溶性糖茶多糖变化规律相似,在普洱茶成品中的含量相差不大.采用GC-MS色质联用归一化峰面积计算方法,对普洱茶成品进行香气成分比较检测,结果显示,处理1成品以醇类、碳氢化合物和酯类物质为主;处理2成品与对照成品在香气组分上相似,都是以醇类、酮类和醛类物质为主.结果证明日光晒干至含水量为26.9 %的晒青茶为原料加工普洱茶具有可行性,为企业改进工艺、稳定品质提供参考.

Study on Variations of Quality of Pu-erh Tea Processed by Sun-dry Tea of Different Water Content

The variations of quality of Pu-erh tea processed in common were studied by using sun-dry tea of different water content as raw material. Sensory tests showed: the Pu-erh tea processed by sun-dry tea of 26.9 % water content(treatment 2) was similar to the Pu-erh tea processed by sun-dry tea of 11.6 % water content(CK) in quality,and they were superior to the Pu-erh tea processed by sun-dry tea of 43.5 % water content(treatment 1).Test of physics and chemistry index showed: the variations of polyphenols, amino acids, caffeine, theaflavins, thearubigins, theabrownin, water extracts and water-soluble carbohydrates during pile-fermentation of Pu-erh tea in treatments was similar,and the difference of Pu-erh tea products in physics and chemistry index was not obvious.The GC-MS peal area calculation method was adopted to test the aroma components in Pu-erh tea producets.The results showed treatment 1 product was identified with higher contents of alcohols, hydrocarbons and esters, treatment 2 product and CK product was identified with higher contents of alcohols, ketones and aldehydes. The results proved that it was probable to process Pu-erh tea by sun-dry tea of 26.9 % water content as raw material. All these provided some reference for improving manufacturing methods and stabilizing quality.