鸭脂氧化及其挥发性香气成分气相色谱-质谱分析

Optimization of Conditions for Controlled Oxidation of Duck Fat and Gas Chromatography-Mass Spectrometry Analysis of Volatile Aroma Components

以过氧化值、p-茴香胺值、酸值表示鸭脂的氧化状态,通过单因素试验和感官鉴定研究氧化温度和时间对鸭脂氧化的影响,确定以制备鸭肉香精前体物为目标的鸭脂氧化条件为氧化温度120℃、时间4 h。在此条件下,鸭脂的过氧化值为22.30 meq/kg,p-茴香胺值为7.04,酸值为0.93 mg KOH/g,具有强烈的脂肪香气以及轻微的油炸气息。通过固相微萃取-气相色谱-质谱分析氧化前后鸭脂的挥发性香气成分,氧化后鸭脂共检测出32种化合物,与氧化前相比,种类及含量均有所增加,其中醛类物质11种,含量为42.29%,其中己醛含量高达29.40%。另外还检测出烃类、呋喃、醇类、羧酸类等多种呈香化合物,为后期以氧化鸭脂为原料进行Maillard反应制备鸭肉香精的技术开发提供参考。

By means of single-factor experiments and sensory evaluation, main factors affecting the peroxide value （POV）, p-anisidine value （p-AV） and acid value （AV） of oxidized duck fat, including oxidation temperature and duration, were investigated. The optimal controlled oxidation conditions of duck fat were determined as 120 ℃ and 4 h. Under these conditions, the POV of oxidized duck fat was 22.30 meq/kg, p-AV 7.04 and AV 0.93 mg KOH/g. It had a strong fatty aroma and a slight smell of frying fat. In total 32 volatile aroma components were detected in oxidized duck fat by solid phase micro-extraction and gas chromatography-mass spectrometry （SPME-GC-MS）, including 11 aldehydes （together accounting for 42.29% of the total amount of volatile compounds） with hexanal accounting for up to 29.40%. Compared with fresh duck fat, oxidized duck fat contained increased kinds and amounts of volatile compounds. In addition, many other aroma components were also detected, including hydrocarbons, furans, alcohols and carboxylic acids. These results will provide references for the preparation of duck meat flavoring by Malllard reaction from oxidized duck fat.