Zhongguo youzhi (Sep 2023)
预处理技术对压榨山茶油品质 及挥发性风味成分的影响Effect of pretreatment techniques on the quality and volatile flavor components of pressed oil-tea camellia seed oil
Abstract
为了对油茶籽高值化预处理技术的发展和高附加值山茶油产品的开发提供参考,以油茶籽为实验材料，未经任何预处理的油茶籽作为对照组，直接进行压榨制油，研究微波（800 W，4 min)、烘烤(140 ℃，30 min)、焙炒(120 ℃，1 h）和红外（150 ℃，55 min）预处理技术对油茶籽出油率，压榨山茶油酸值、过氧化值、脂肪酸组成及含量、总甾醇含量及挥发性风味成分的影响。结果表明：与对照组相比，微波、烘烤、焙炒和红外预处理使油茶籽的出油率分别提高了5.92、3.52、2.93、3.86百分点；不同预处理组山茶油的酸值(KOH)在0.20~2.00 mg/g之间，过氧化值在0.98~2.07 mmol/kg之间，均在山茶油国家标准范围内；4种预处理技术对山茶油的脂肪酸组成无显著影响；4种预处理技术在一定程度上降低了山茶油中总甾醇含量，但与对照组相比差异微小；5组山茶油中共检测出34种挥发性风味成分，其中醛类化合物含量均最高；5组山茶油挥发性成分的种类和含量差别较大，预处理技术可丰富山茶油特征风味物质种类，使山茶油整体风味由清淡的油脂香转变为浓烈的油脂香和坚果香。综上，4种预处理技术在不影响压榨山茶油品质的基础上，可提高出油率和山茶油整体风味，从省时、高效率角度考虑，微波为最佳预处理技术。In order to provide a reference for the development of high-value pretreatment technology and the development of high value-added oil-tea camellia seed oil products, the oil-tea camellia seeds were pressed directly for oil extraction using without any pretreatment as the control group, and the effects of microwave (800 W, 4 min), roasting (140 ℃, 30 min), frying (120 ℃, 1 h) and infrared (150 ℃, 55 min) pretreatment techniques of oilseeds on the oil yield of oil-tea camellia seeds, acid value, peroxide value, fatty acid composition and content, total sterol content, and volatile flavor components of the pressed oil-tea camellia seed oil were investigated. The results showed that compared with the control group, the oil yield of oil-tea camellia seeds increased by 5.92, 3.52, 2.93 and 3.86 percentage points by microwave, roasting, frying and infrared pretreatments, respectively. The acid values of oil-tea camellia seed oil with different pretreatment techniques ranged from 0.20 mgKOH/g to 2.00 mgKOH/g, and the peroxide values ranged from 0.98 mmol/kg to 2.07 mmol/kg, which were within the range of the national standard for oil-tea camellia seed oil. The fatty acid composition of oil-tea camellia seed oil was not significantly affected by the four pretreatment techniques. The four pretreatment techniques reduced the total sterol content of oil-tea camellia seed oil to some extent, but the difference was minimal compared with the control group. A total of 34 volatile flavor components were detected in the five groups of oil-tea camellia seed oils, of which the aldehydes content was the highest. The types and contents of volatile flavor components in the five groups of oil-tea camellia seed oils varied greatly, and the pretreatment techniques could enrich the characteristic flavor substances and change the overall flavor of oil-tea camellia seed oil from a light oily aroma to a strong oily and nutty aroma. In summary, the four pretreatment techniques can improve the oil yield and the overall flavor of oil-tea camellia seed oil without affecting the quality of the pressed oil-tea camellia seed oil, and microwave is the best pretreatment technique in terms of time saving and high efficiency.
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