为揭示Streptococcus thermophilus ND03在牛乳发酵过程和4 ℃贮藏期间产生的挥发性风味物质及其变化情况，采用3种不同纤维涂层的萃取头，运用固相微萃取-气相色谱-质谱联用（SPME-GC-MS）技术对各阶段发酵牛乳样品进行检测分析，利用主成分分析法分析各阶段样品的特征性风味物质并对各阶段样品进行感官评定。结果表明：利用50/30 ?滋m DVB/CAR/PDMS、65 ?滋m PDMS/DVB和100 ?滋m PDMS 3种萃取头分别检测出86、66和62种挥发性物质。在发酵及贮藏期间，挥发性风味物质的数量与含量存在动态变化。由主成分分析结果可知，样品的特征性风味物质在发酵期间为醛类、酮类及杂环化合物，在贮藏0 d（发酵终点） 为醇类及含氮化合物，在贮藏1、3 d为酯类及芳香族化合物，在贮藏7、14 d为烃类及酸类化合物。由感官评定结果可知，贮藏1 d的样品在色泽、滋味、气味及组织状态方面具有良好表现。菌株Streptococcus thermophilus ND03作为发酵剂具有潜在的工业应用前景。
The aim of the research was to study the volatile compounds of fermented cow milk during the fermentation and storage period at 4 ℃ using the starter strain named Streptococcus thermophilus ND03 with the method of solid phase microextraction and gas chromatography coupled with mass spectrometry（SPME-GC-MS） by three different extraction fibers. The numbers of extractions detected by different extraction fibers named 50/30 ?滋m DVB/CAR/PDMS，65 ?滋m PDMS/DVB and 100 ?滋m PDMS were 86，66 and 62，respectively. The amount and the content of volatile compounds showed significantly different between the process of fermentation and storage period. The principal component analysis results showed that aldehyde compounds，ketone compounds and heterocyclic compounds were the characteristic aroma species of samples during fermentation period. In the storage period，alcohols and nitrogen-containing compounds were the characteristic aroma species of samples named stored 0 d，namely end-point of fermentation；aromatic compounds and esters compounds were found to be the characteristic aroma species of samples named stored 1 d and 3 d；acid compounds and hydrocarbons were the characteristic aroma species of samples of stored 7 d and14 d. The sensory evaluation results suggested that the samples named stored 1 d showed good performance in color，taste，flavor and texture. All in all，Streptococcus thermophilus ND03 as the starter culture has potential industrial application prospect.
王丹,周亭亭,丹彤,张和平,孟和毕力格.Streptococcus thermophilus ND03在牛乳发酵过程及贮藏期间挥发性风味物质分析[J].食品与生物技术学报,2019,38(5):15-22.
WANG Dan, ZHOU Tingting, DAN Tong, ZHANG Heping, MENGHE Bilige. Volatile Compounds Analysis of Fermented Cow Milk during Fermentation and Storage Using the Starter Streptococcus thermophilus ND03[J]. Journal of Food Science and Biotechnology,2019,38(5):15-22.