焙炒方式對苦茶油品質之影響

Abstract

微波照射會使粒徑大之苦茶籽升溫較快，故易造成中心溫度不均一之現象，而照射亦會引起苦茶油過氧化物之分解及安定性變差。以各種溫度之蒸氣蒸煮發現高溫者油質較差，故蒸煮之蒸氣溫度亦不宜過高。焙炒方式主要分為低溫和高溫兩種，由結果知不焙炒及低溫焙炒者有較佳之貯存品質，其非皂化物中之生育醇含量較高，高溫焙炒者其生育醇含量則較低，造成其安定性較差，此與一般所知以擠壓榨油，會產生高溫之油品，其品質較差，有相當一致之結果。 Central temperature of larger size camellia seeds increased faster than small ones when treated with microwave and the central temperature of seeds became heterogeneous. The POV of oils decreased when the radiating time of camellia seeds prolonged. The decline of POV maybe caused by the crack of hydroperoxides and the increase in CV (carbonyl value) may be caused by the formation of carbonyl compounds. Quality of oils prepared from microwave treated seeds is unstable. It is suggested that the lower the cooking temperature, the better the oil quality when Camellia seeds cooked under five different temperature using steam as heating medium. Two different roasting methods-low and high temperature were used to treat camellia seeds. The results showed blank(without treatment)and low temperature rosating would cause the oil with higher stability in storage and higher amount of tocopherols.