氧化鸡脂和阿拉伯糖/半胱氨酸模型体系的相互作用

The interaction between oxidized chicken fat and arabinose/cysteine model reaction

研究氧化鸡脂对D-阿拉伯糖/L-半胱氨酸模型体系反应所产生挥发性产物的影响,同时对氧化鸡脂和模型体系产物的相互作用进行分析。选择0.4∶0.4(M∶M)的D-阿拉伯糖/L-半胱氨酸水相体系为模型体系,在120℃pH5的条件下反应2 h。在同样条件下,将鸡脂和氧化鸡脂分别加入到模型体系中进行反应,反应体系所产生的挥发性产物采用固相微萃取/气相/质谱联用的方法进行分析,共检测到100多个产物。与模型体系比较,加入鸡脂的体系所产生的噻唑和含硫化合物大大增加,加入氧化鸡脂的体系噻唑和酮类物质含量增加,但产物中检测不到醛类,由此推论醛类物质参与了美拉德反应。如果把氧化鸡脂和模型体系进行简单的混合,醛类和醇类含量增加,而酮类物质消失,醛类和醇类物质含量的提高来源于鸡脂的氧化,但鸡脂氧化没有产生酮类物质。如果氧化鸡脂和模型反应体系再在60℃反应30 min,醛类、噻唑类、醇类以及含硫化合物的含量都有所提高,说明氧化鸡脂和模型反应体系产物之间又进行了新的反应。

Effect of oxidized chicken fat on the volatiles formed in arabinose/cysteine model reaction and interaction between oxidized chicken fat and volatile compounds formed in model reaction were investigated. Arabinose/cysteine0.4 ： 0.4（ M ： M） in aqueous phase was selected as model system and reacted at 120℃ for 2h under pH 5 condition. In the same condition, before the reaction, chicken fat and oxidized chicken fat were added into the model system and reacted respectively. Additionally, 0.6 g oxidized chicken fat was added into the obtained reaction products of model system and mixed homogenously. While another oxidized chicken fat was added into reacted model system at 60℃ and reacted continuously for another 30 min. Volatile compounds formed in the reaction system were analyzed by SPME/GC/MS. More than one hundred volatile components were produced. Comparison with model system, the relative percentage of thiazoles, sulphides formed in the system with chicken fat increased largely. While comparing with the Maillard reaction with chicken fat added, the relative percentage of ketones and thiazoles increased but aldehydes disappeared in the reaction products with oxidized chicken fat added. It could be concluded that aldehydes took part in the Maillard reaction. The relative percentage of aldehydes and alcohols increased but ketones were not detected in the system of mixing simply oxidized chicken fat with the reacted model system. The increase of aldehydes and alcohols came from the oxidation of chicken fat, and ketones were not produced in the oxidation under this condition. Comparing the adding simply oxidized chicken fat, the relative percentage of aldehydes, thiazoles, alcohols and sulphides increased in the heating mixture of oxidized chicken fat with the products of Maillard reaction,. It could be concluded that there are further reaction between products of oxidized chicken fat and Maillard reaction.