摘要
嗜热链球菌是发酵乳生产中常用的发酵剂菌种之一。以分离自传统发酵乳制品曲拉中的1株具有良好风味的嗜热链球菌IMAU80285为试验菌株,采用气相色谱-质谱联用仪等仪器和主成分分析、相似度分析等方法,对该菌株在发酵乳制作和贮藏期间产生的风味物质进行全面、系统的分析。结果表明:在发酵乳制作和贮藏期间,从嗜热链球菌IMAU80285中共测得84种风味物质,主要包括酸类化合物(11种)、醛类化合物(13种)、酮类化合物(12种)、醇类化合物(22种)、酯类化合物(9种)、烷烃类化合物(14种)、含氮类化合物(3种)。主成分分析结果表明:关键性风味物质(OAV≥0.1)在发酵初期(发酵4,6 h)和前发酵与贮藏期间(后熟,贮藏1,2,3,7,14 d)有明显的区分,发酵初期(发酵4,6 h)和前发酵时,与乙偶姻、庚醛、1-壬醇、己酸乙酯等17种关键性风味物质(OAV≥0.1)有较强的相关性,而贮藏期间(后熟,贮藏1,2,3,7,14 d)与2,3-丁二酮、3-甲基-1-丁醇、丁酸乙酯等7种关键性风味物质(OAV≥0.1)的相关性较强;重叠色谱图及相似度分析结果表明,发酵乳中的风味物质在发酵乳制作及贮藏期间变化显著,随着贮藏时间的延长,发酵乳的风味差异明显。
Streptococcus(St.)thermophilus is one of the most commonly used starters in fermented milk production.In the present study,St.thermophilus IMAU80285 isolated from the traditional fermented dairy product qula with specific flavor properties was selected and detected for the flavor substances produced during the production and storage of fermented milk,by gas chromatography-mass spectrometry methods.Principal component analysis and similarity analysis was then used to systematically analyze the flavor components.The results showed that the total of 84 volatile compounds were finally detected in fermented milk during fermentation and storage,including aldehydes(13 species),ketones(12 species),acids(11 species),esters(9 species),alcohols(22 species),hydrocarbon compounds(14 species)and nitro-gen-containing compounds(3 species).Principal component analysis revealed that the apparent distinction in the flavor substance(OAV≥0.1)between the initial stage of fermentation(4,6 h of fermentation)and the completion of fermentation and whole storage period(after ripening,1,2,3,7,14 d).At the beginning of fermentation(4,6 h of fermentation)and at the completion of fermentation,there were positive correlations with 17 kinds of flavor substances with OAV≥0.1,such as acetoin,heptaldehyde,1-nonanol and ethyl hexanoate;while positive correlations were observed with 7 kinds of flavors with OAV≥0.1,such as 2,3-butanedione,3-methyl-1-butanol and ethyl butyrate during storage(after ripening,1,2,3,7,14 d).The results of overlapping chromatogram and similarity analysis showed that the flavor substances in fermented milk changed significantly during the production and storage of fermented milk.It is obviously noting that significant difference in composition of flavor substances with the increase of storage time.
作者
任为一
陈海燕
李婷
田佳乐
丹彤
张和平
Ren Weiyi;Chen Haiyan;Li Ting;Tian Jiale;Dan Tong;Zhang Heping(Key Laboratory of Dairy Biotechnology and Engineering,Ministry of Education,Key Laboratory of Dairy Products Processing,Ministry of Agriculture and Rural Affairs,Inner Mongolia Agricultural University,Hohhot 010018)
出处
《中国食品学报》
EI
CAS
CSCD
北大核心
2020年第9期190-202,共13页
Journal of Chinese Institute Of Food Science and Technology
基金
国家自然科学基金项目(31460446,31471711)。
关键词
挥发性风味物质
嗜热链球菌
气味活度值
主成分分析
气相色谱指纹图谱
volatile flavor compounds
Streptococcus thermophilus
odor activity value
principal component analysis
chromatographic fingerprinting
