【作者】 李依娜；

【导师】 钟海雁； 李忠海；

【作者基本信息】 中南林业科技大学 ， 农产品加工及贮藏工程， 2010， 硕士

【摘要】 茶油是从普通油茶的成熟种子中提取出来的一种淡黄色澄清状油。油脂品质是油脂商业价值及食用价值的重要体现。油脂品质与其提取工艺有很大关系。因此,开展对茶油加工工艺、品质和香气成分的研究,具有一定的理论和实际意义。现通过SPSS软件对焙烤及水代法提取所得茶油的品质及香气成分进行主成分分析,为油茶资源开发利用提供理论基础和科学依据。本试验以湖南常德产的普通油茶寒露籽为试验材料,对水代法提取普通油茶籽油的工艺及所得茶油的品质及香气成分进行了研究,研究内容包括四个方面：普通油茶籽油水代法提取工艺的研究；不同破乳方法对乳化油中油回收率影响的研究；焙烤对水代法提取的茶油重要品质指标影响的研究；焙烤对水代法提取的茶油香气成分影响的研究。主要试验结果如下：以焙烤条件为主要考虑因素的水代法提取茶油的工艺条件,以出油率为指标,获得了茶油提取的最佳工艺条件：水料比5：1(v/w),焙烤温度190℃,焙烤时间20 min和提取时间120 min,在此优化条件下进行验证试验,三次平均出油率可达80%。通过对破乳方法的研究表明：冷冻解冻后低速离心的效果最好,乳状液中油回收率达到88.01%；单纯靠改变离心的速度和时间的效果次之,乳状液中油回收率为62.78%；而通过不同加热条件后低速离心的效果最差,其乳状液中中油回收率仅有52.05%。以普通油茶的焙烤时间和温度为分析对象,采用主成分分析法分析其与茶油出油率、水分及挥发物含量、过氧化值、酸值、碘值、皂化值及K值的关系。结果表明：当焙烤温度为170℃时,茶油的综合品质都随着焙烤时间的延长而呈下降的趋势,焙烤5 min时的茶油的综合品质较高,随着时间的延长,茶油的综合品质下降,在20 min时降到选定条件中的最低值；当焙烤时间为10 min时,茶油的综合品质都随着焙烤温度的升高而呈下降的趋势,温度为150℃下焙烤的茶油综合品质相对较高,随着焙烤温度升高,茶油综合品质明显下降,210℃时达到最低点。对方法的可靠性进行了评价,10种标准品标准曲线呈现出良好的线性关系,R2在0.940～0.999之间,检测限在0.111μg/g～0.387μg/g之间；本方法加标回收率为93.60%-101.25%,平均值为97.36%；在重复性试验中,10种标准品在经6次连续测定的RSD范围在0.96%-5.00%,可见该方法具有较好的可操作性。以普通油茶籽油为试验对象,采用主成分分析法探讨焙烤时间和温度对其香气成分的影响。结果表明：在170℃下焙烤5 min时对普通油茶籽油香气的影响最大,其次为在170℃下焙烤10 min、15 min等。普通油茶籽焙烤后经水代法提取的茶油香气中,受到焙烤条件影响最大的是乙酸乙酯、正辛醇等。更多还原

【Abstract】 Camellia oil is extracted from Camellia oleifera seeds, and its quality is embodiment of the value of commercial and edible. The quality of oil is greatly connected with the technics of extraction. Thus, the researchs for oil processing technology and quality and aromatic components have important significance for theory and practice.In this study, the quality and aromatic components of Camellia oil have been analysised by principal components analysis (PCA) by SPSS software. The results would provide some theoretical and practical signification for oil industry.In this study, Camellia oleifera seeds from Changde Hunan were used as the raw materials, aqueous extraction technology on the common Camellia oleifera seed oil, the quality and aroma of camellia oil were researched. This paper included three parts as follows:the research of aqueous extraction technology on the common Camellia oleifera seed oil; the research of demulsification; the research of roasting on camellia oil quality and the aroma components of water extraction. The main results were shown as follow:With the oil extraction rate as indicators, The optimum extraction procedure was obtained as follows:camellia seed paste was mixed five fold water (v/w), then roasted at 190℃. for 20 min, at last incubation in constant water bath for 120 min. Under optimum conditions, the certification test showed three times average oil yield was up to 80%.The results of demulsification was shown as following:Effect of freezing thawing was the best and emulsion recovery rate could arrive 88.01%; simply by changing the speed and time of centrifugal, the effect was the second, emulsion recovery rate was 62.78%; while, different heating conditions’s effect was the worst, its emulsified oil recovery rate was only 52.05%.The relationship between roasting time, temperature and extracting yield and main chemical guality indices of Camellia oleifera was analysised by Principal Component Analysis (PCA) with SPSS software. The results was shown as following: When the roasting temperature was 170℃, the overall quality of camellia oil was downward trend with the roasting time longer. The best roasting conditions contributed to synthetic oil quality of camellia oil were at 170℃for 5 min, then, as time longened, camellia oil comprehensive quality dropped and reduced to the minimum value at 170℃for 20 min; When the roasting time was 10 min, the comprehensive quality of camellia oil was downward trend with the roasting temperature riser. The comprehensive quality of camellia oil was relatively higher at 150℃for 10 mins. With the roasting temperature raised, camellia oil comprehensive quality Significantly improved and reached the lowest point at 210℃.Calibration curves of 13 standards showed good linearity, with coefficients of determination(R2) ranging from 0.940 to 0.999 and limits of detection(LOD) from 0.111μg/g to 0.387μg/g. The recoveries and coefficient of variation in standards determination ranged from 93.60% to 101.25% and from 0.96% to 5.00%.The effect of roasting time and temperature on the aromatic components of Camellia oleifera was investigated. According to the results of PCA, The conditions that had the most effects on oil of Camellia oleifera were at 170℃for 5 min, and followed by baking at 170℃for 10 min,15 min and so on. Ethyl acetate and n-octanol were the aromatic components that mainly affected by roasting time and temperature.更多还原