茶叶籽仁水浆胶体特性及其静置发酵分层机理研究

The crude oil produced by all of the existing process for tea seed oil production is dark with color, turbid, and bitter with taste. In the process of finding resolution for the difficult problem, the team found a new phenomenon, and created a" static fermentation process for tea seed oil production" based on this phenomenon. This phenomenon is: tea seed water static colloid (after referred to as colloid) can be naturally divided into three layers after static fermentation, and by heating the top layer scooped out from fermented colloid liquid, tea seed oil without variegated color and peculiar smell can be produced. To clarify the mechanism of fermented solution stratification by static fermentation, the team plans to identify microbial species in the fermentation with molecular biology method, to determinate the change rule of colloid total potential in the fermentation process with Zeta-Potential, to analyze colloid biochemical composition and its change rule in the static fermentation process with liquid mass method and temperament method, to study the types and forms of the colloidal particles with digital microscopic observation combined with chemical staining, to screen the main factors influencing the delamination of fermented colloid liquid with principal component analysis, to study surface membrane characteristics of the tea seed oil body colloidal particle with fluorescence and confocal microscopic observation, and enzymatic method. Illustrating the occurrence mechanism of this phenomenon can provide theoretical basis to optimizing "static fermentation process for tea seed oil production " of the team , promote the industrialization of the process, and to provide technical support to solving the common technology problems in tea seed oil production.

目前所有茶叶籽油生产工艺均存在毛油颜色深暗、浑浊、味道混杂苦涩等难题。在研究此难题过程中，项目组发现了一种新现象，并以此现象为基础创立了"茶叶籽油静置发酵生产工艺"。此现象是：茶叶籽水浆胶体（后简称胶体）静置发酵后可以自然分为3层，取出发酵液顶层加热，即可产出无杂色、无异味茶叶籽毛油。为阐明此静置发酵分层现象的发生机理，项目组拟采用分子生物学法鉴定发酵微生物种类，用zeta电势法测定发酵过程中胶体总电势的变化规律，用液质法、气质法分析胶体液的生化组成及其在静置发酵过程中的变化规律，采用化学染色结合数码显微观察研究胶粒的种类及形态，用主成分分析法筛选影响胶体发酵液分层的主要因素，用荧光、共聚焦显微观察及酶学方法研究茶叶籽油脂体胶粒表层膜的特征。阐明此现象的发生机理可以为优化项目组的"茶叶籽油静置发酵生产工艺"提供理论依据，促进该工艺产业化，为解决目前茶叶籽油生产工艺的共同难题提供技术支撑。

主要研究内容分为如下4个方面。茶叶籽水浆胶体发酵分层现象研究：茶叶籽水桨胶体发酵到4-6h之间，胶体体系稳定性破坏，胶体分为明显三层。发酵4h之前，发酵液蛋白质、多糖、干物质含量逐渐增加，pH 逐渐降低； 4h之后，干物质、蛋白质、多糖含量及pH逐渐降低，16h以后基本稳定。研究结果为进一步研究及利用茶叶籽水浆胶体发酵分层现象奠定了基础。.茶叶籽水浆胶体发酵液三层生化成分研究：茶叶籽水浆胶体发酵液顶层产率约为30.15%，顶层含水量、蛋白质含量、纤维素含量、茶叶籽油含量分别为16.43%、18.29%、9.91%、52.19%；在脂肪酶、胰蛋白酶、a-淀粉酶、纤维素酶、木瓜蛋白酶5种酶类中，以脂肪酶对茶叶籽油脂体的酶解效果最好。发酵液底层干物质产率约为14%，底层干物质含淀粉60%、茶皂素20%、茶叶籽多糖10%、其他杂质10%。茶叶籽水浆胶体发酵液中层干物质产率为0.4%，干物质约含0.07%的茶叶籽油、60%的茶皂素。三层生化成分的研究结果是揭示茶叶籽水浆胶体发酵分层机理的基础之一。.茶叶籽水浆胶体发酵微生物研究：茶叶籽水浆胶体发酵微生物最适培养温度为25℃，培养基为MRS。分离鉴定出三种微生物，分别为茶叶籽酵母（编号为Meyerozyma caribbica JJZ11）、茶叶籽乳杆菌（编号为：Lactobacillus plantarum subsp. Plantarum JJZ12）及茶叶籽产液醋酸菌（编号为 Gluconacetobacter liquefaciens JJZ21）；并对前二者进行了保藏，保藏号分别为CCTCC M 2016470及CCTCC M 2016471。在发酵开始时接种茶叶籽酵母（6066666个/ml）时，可以提高毛油产量30%以上。研究结论是揭示茶叶籽水浆胶体发酵分层机理的又一基础。.茶叶籽油发酵工艺技术参数优化研究：茶叶籽最佳浸泡时间、温度分别为16h及25℃，浸泡最佳加水量为1:2；茶叶籽水浆胶体最佳发酵温度为35℃、最佳发酵时间为16h，茶叶籽酵母最佳接种量为6066666个/ml。优化工艺的茶叶籽毛油产率18-22%、茶叶籽淀粉产率6%-10%，油茶籽油产率28-35%。毛油纯化后的成品油质量达到国家一级油标准（GB11765-2003）。 .发表权威核心期刊论文9篇，EI收录1篇；申请发明专利4项，授权2项。