乳提技术对红茶产品风味物质的影响及工艺放大可行性

Effect of Milk-based Extraction Technology on Flavor Compounds of Black Tea Products and Its Feasibility of Process Scale-up

本文以斯里兰卡红茶为原料,采用气相色谱-质谱和高效液相色谱法研究以稀奶油为介质提取红茶香气物质的最佳工艺参数,并比较不同脂肪体系(稀奶油、脱脂奶、全脂奶、黄油、椰子油)与传统水提介质对红茶香气物质和滋味物质的影响,进一步分析在最佳工艺条件下中试生产的红茶冻干粉产品品质。结果表明:以稀奶油为提取介质提取红茶的最佳工艺参数为脂肪含量3.8%、料液比1∶20、提取温度80℃、提取时间30 min。相较于传统水提技术,采用稀奶油和全脂奶为提取介质的乳提技术更有利于红茶中香气物质的提取,如体现斯里兰卡红茶特征冬青味的水杨酸甲酯,其含量分别提高了151%和172%。稀奶油提取的红茶水溶性滋味成分含量与水提方式相近,而全脂奶和脱脂奶提取的红茶总单宁含量显著增加(P<0.05)。不同动植物油脂来源的油脂体系影响红茶提取液香气物质含量,采用稀奶油提取红茶的香气物质含量高于黄油和椰子油,均质乳化能显著提升3种油脂体系对红茶香气物质的提取率。按照最佳试验工艺参数进行中试生产,发现以稀奶油为提取介质的乳提红茶冻干粉香气物质含量显著高于水提红茶冻干粉。综合以上结果认为,采用稀奶油为提取介质的乳提技术相较于传统水提能更有效地提升红茶产品的风味,同时中试生产证明乳提技术的工艺放大具有可行性。本试验结果可为制备具有独特风味和较高营养价值的含乳茶饮品提供实际生产指导。

This paper investigated the optimal process parameters for extracting aroma compounds from Sri Lankan black tea with cream as the extraction medium.The effects of different fat-based systems(cream,skimmed milk,whole milk,butter,and coconut oil)and traditional water extraction medium on the aroma and taste compounds of black tea were compared by using gas chromatography-mass spectrometry and high-performance liquid chromatography.Furthermore,the quality of freeze-dried black tea powder produced on a pilot-scale under optimal process conditions was also analyzed.The results indicated that the optimal process parameters for cream-based extraction of black tea were determined as follows:fat content of 3.8%,liquid-to-material ratio of 1∶20,extraction time of 30 minutes,and temperature of 80℃.Compared with the water extraction,cream and whole milk-based extraction were more favorable for extracting aroma compounds from black tea,for example,methyl salicylate,which contributed to the characteristic wintergreen flavor of Sri Lankan black tea,increased by 151%and 172%,respectively.The content of water-soluble taste components in black tea extracted by cream were similar to those extracted by water,while the contents of total tannins in black tea extracted by whole milk and skimmed milk significantly increased(P<0.05).The fat-based systems from different animal and plant sources affected the content of aroma compounds in the black tea extracts.The content of aroma compounds in black tea extracted by cream was higher than those extracted by butter and coconut oil,and emulsification significantly improved the extraction efficiency of aroma compounds for all three fat-based systems.The quality of the freeze-dried black tea extracts varied during pilot-scale production using the optimal experimental process parameters.It was found that freeze-dried black tea powder obtained through cream-based extraction exhibited higher content of aroma compounds compared with the freeze-dried black tea powder obtained through water-based extraction.The above results demonstrated that the milk-based extraction technology using cream as the extraction medium could more effectively enhance the flavor of black tea products compared with the traditional water extraction.At the same time,pilot-scale production proved the feasibility of the milk-based extraction technology in terms of process scale-up.The results of this experiment could provide practical production guidance for preparing the production of milk-based tea beverages with unique flavors and higher nutritional value.