3种2-丁烯醛类食用香料的稳定性研究

为研究2-丁烯醛类食用香料在不同储存条件下的稳定性,采用气相色谱-质谱联用仪考察了储存温度、相对湿度和顶空气体中氧气的体积分数对反-2-甲基-2-丁烯醛、3-甲基-2-丁烯醛和2-苯基-2-丁烯醛在储存过程中稳定性影响。结果表明,在考察的3种因素中对2-丁烯醛类食用香料的稳定性影响由大到小依次为顶空气体中氧气的体积分数、储存温度和相对湿度。装有2-丁烯醛类香料的容器顶空中含有空气时,在室温下储存20周,其含量降到90 %左右。为了保证2-丁烯醛类香料的质量,包装打开后建议在12周内用完；这类香料不耐高温,在调配耐高温香精时应该少量使用。为确定3种2-丁烯醛在储存过程中生成的新物质,采用质谱和两种不同极性色谱柱上的保留指数对生成的新物质进行了初步定性。结果表明:反-2-甲基-2-丁烯醛和3-甲基-2-丁烯醛容易被氧化生成反-2-甲基-2-丁烯酸和3-甲基-2-丁烯酸,而2-苯基-2-丁烯醛在储存过程中产生的主要物质是2-甲基-3-苯基-2-丙烯酸和苯丙酮。这类香料应该保存在低温和惰性氛围中。

Investigation on Stability of Three 2-Butenal Flavor Compounds

To study the stability of 2-butenal flavor compounds at different storage conditions, the effects of storage temperature, relative humidity, and the volume content of headspace oxygen on the stability of E-2-methyl-2-butenal, 3-methyl-2-butenal and 2-phenyl-2-butenal were investigated by gas chromatography-mass spectrometry. The results showed that the influence order on the stability of 2-butenals in turn were the volume content of headspace oxygen, the storage temperature, and the relative humidity. After 20 weeks storage at room temperature with air in the headspace of the container, the content of 2-butenals was dropt to 90%. To ensure the quality of 2-butenal, it should be suggested to use within 12 weeks after first opening the container. These three 2-butenals should be less used for formulating the high-temperature-resistant flavorings because they were not resistant to high temperature. Mass spectrum and retention indexes in two different polar chromatographic columns were applied to determine the compounds newly formed during storage. The results showed that E-2-methyl-2-butenal and 3-methyl-2-butenal were easily oxidized to produce E-2-methyl-2-butenoic acid and 3-methyl-2-butenoic acid, respectively. However, 2-methyl-3-phenyl-2-propenoic acid and 1-phenyl-1-propanone were derived from 2-phenyl-2-butenal during storage. The results also indicated that 2-butenal flavor compounds should be preserved at lower temperature and at inert gas atmosphere.