应用于烘焙产品的咖啡麦芽预拌粉储藏期内的品质变化研究

Study on the Quality Changes of Coffee Malt Premixed Powder Applied to Baking Products during Storage

为研究咖啡麦芽预拌粉随着储藏期延长的品质变化规律,将咖啡麦芽预拌粉分别储存于25℃和35℃、相对湿度为50%的环境中,对其整个储藏期内水分、脂肪酸值、降落数值进行监测;采用固相微萃取法结合气相色谱-质谱法对其储藏期内挥发性化合物进行分析。结果表明,随着储藏期的延长,水分整体呈下降趋势,脂肪酸值和降落数值总体呈上升趋势,且储藏温度越高,变化越明显;分析出咖啡麦芽预拌粉主要挥发性化合物41种,主要包括醛类13种、杂环类15种、酯类7种、醇类4种、酮类2种,其中,醛类物质(正己醛、壬醛、反式-2-壬烯醛)的相对浓度随储藏期的延长有增加趋势。

In order to study the quality change of coffee malt premixed powder with the extension of storage period,the coffee malt premixed powder was stored at the environment where the temperature is 25℃and 35℃,respectively,and the relative humidity is 50%respectively.Its moisture,fatty acid value and falling value were monitored during the whole storage period.The volatile compounds were separated and identified by solid phase microextraction accompanying gas chromatography-mass spectrometry during the whole storage period.The results demonstrated that with the extension of storage period,the overall moisture content shows a falling trend,while the fatty acid value and falling value show an overall rising trend.The higher the storage temperature,the more significant the change is 41 kinds of main volatile compounds of coffee malt ready mixed powder were identified.It mainly includes 13 kinds of aldehydes,15 kinds of heterocycles,7 kinds of esters,4 kinds of alcohols and 2 kinds of ketones.Among them,the relative concentration of aldehydes(n-hexanal,nonanal,trans-2-nonenal)showed an increasing trend with the extension of storage period.