茶油深层煎炸稳定性的研究

以棕榈油作对照,采用精炼茶油进行深层煎炸。测定煎炸用以及薯条中的油脂在煎炸过程中的主要化学指标,即酸值、过氧化值、羰基价、碘价、皂化值、K值及极性化合物含量等的变化;分析煎炸用茶油的挥发性成分的变化;评价薯条的感官品质。试验结果表明:连续煎炸30h(120批次),茶油及棕榈油的酸值、过氧化值、羰基价、极性化合物含量和K值均逐渐升高,碘价和皂化值则逐渐降低;总挥发物含量逐渐增加,而一些小分子质量挥发物呈先升后降的趋势;用新鲜油煎炸的薯条的总体得分较高;除过氧化值外,薯条中茶油的其它测定指标的变化滞后于煎炸用油的变化。对照国标GB7102,24h时除茶油中的羰基价超标外,其它指标至30h时仍处于规定限值范围。茶油的深层煎炸寿命为24h(96批次)。用茶油煎炸的薯条易被消费者接受。

Stability of Camellia Oil Following Deep Frying

Refined camellia(GB 11765,pressed oil,Grand 1) was used for deep frying for French fryer with comparision of palm oil.During 30 h(120 batches) frying procedure,acid,peroxide,carbonyl,iodine,saponification,and K values and polar compounds of frying oil and oil extracted from French fryer were analysed.Volatile of frying oil and sensory attributes of French fryer were also evaluated.The results were showed that acid,peroxide,carbonyl,and K values and polar compounds of camellia and palm oils increased gradually,while iodine and saponification values decreased;Total volatile accumulated with a trend of ’up-down’ of lower molecular weight volatiles;Total score of French fryers fried with fresh oil and with camellia oil were higher than those from the latter bathches and fried with palm oil;Except of peroxide value,other values assessed in the oil extracted from French fryer were lower than those in the relative batch frying oil.According the regulation of GB 7102,except that carbonyl value at 24 h exceeded the limit,other indices were still within the required limit.The factors as given above indicate that the frying life of camellia oil should be 24 hours and the French fryer fried with camellia oil could be more acceptable by consumers.