不同热处理条件对副干酪乳酪杆菌K56发酵乳质构和风味物质变化的影响

Influence of varying heat treatment conditions on texture and flavor compound profiles in fermented milk produced by Lacticaseibacillus paracasei K56

中文关键词:  K56发酵乳  热处理  质构特性  风味物质

英文关键词:Lacticaseibacillus paracasei K56  fermented milk  heat treatment  textural properties  flavor compounds

中文摘要:

      目的 分析不同热处理工艺对副干酪乳酪杆菌K56发酵乳的质构及其挥发性和非挥发性风味物质的影响。方法 对副干酪乳酪杆菌K56发酵乳进行80~121 ℃的热处理, 并采用质构分析仪、顶空固相微萃取-气相色谱-质谱技术(headspace-solid phase microextraction-gas chromatography-mass spectrometry, HS-SPME-GC-MS)和液相色谱-串联质谱技术(liquid chromatography-tandem mass spectrometry, LC-MS/MS)分析其质构及挥发性、非挥发性风味物质的种类和含量变化。结果 80~110 ℃热处理条件下, 随着热处理温度的增加, K56发酵乳的硬度降低, 内聚性和弹性增加; 在110 ℃、4 s处理下, 内聚性和胶着性展现出最佳质构特性, 其硬度为6.2 g, 内聚性增加到0.18, 弹性为0.708 mm, 胶着性为4.8 g。热处理后检测到59种挥发性风味物质, 其中90~121 ℃处理显著增加了酮类和醇类; 气味活性值(odor activity value, OAV)分析显示发酵乳的主要风味物质为酯、酮和有机酸, 以δ-癸内酯和乙酸异丁酯为主要贡献物质。在652种非挥发性代谢物中, 热处理90 ℃、15 min和110 ℃、4 s, 100 ℃、15 min和115 ℃、4 s条件下存在相似的代谢物。在对照组和6个热处理组样品中, 共发现12个显著不同的吲哚物质。结论 不同热处理条件下, K56发酵乳的质构特性和风味物质发生显著变化, 110 ℃、4 s处理下效果最佳, 不仅改善其质构特性, 还增强其风味物质的多样性, 为发酵乳的品质提升提供了重要的科学依据。

英文摘要:

      Objective To investigate the effects of varying heat treatment conditions on the texture profile and volatile/non-volatile flavor compound dynamics in fermented milk produced by Lacticaseibacillus paracasei K56. Methods Fermented milk produced by Lacticaseibacillus paracasei K56 was subjected to heat treatment at temperatures ranging from 80 to 121 ℃. The texture, volatile flavor compounds and non-volatile flavor compounds were analyzed using a texture analyzer, headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results Under heat treatment conditions ranging from 80 to 110 ℃, the hardness of fermented milk produced by Lacticaseibacillus paracasei K56 decreased, while cohesiveness, and springiness increased. The optimal textural properties, particularly in terms of cohesiveness and gumminess, were achieved at 110 ℃ for 4 s, exhibiting a hardness of 6.2 g, cohesiveness of 0.18, springiness of 0.708 mm, and gumminess of 4.8 g. The 59 kinds of volatile flavor compounds were detected following heat treatment, with the 90–121 ℃ range significantly enhancing the levels of ketones and alcohols. Odor activity value (OAV) analysis identified esters, ketones and organic acids as the dominant flavor contributors in the fermented milk, with δ-decalactone and isoamyl acetate serving as the key odorants. Among the 652 kinds of non-volatile metabolites analyzed, the heat treatment groups 90 ℃, 15 min and 110 ℃, 4 s, 100 ℃, 15 min and 115 ℃, 4 s exhibited overlapping metabolites. Comparative analysis revealed 12 significantly differentiated indole compounds among the control group and 6 heat-treated samples. Conclusion The textural properties and flavor compounds of fermented milk produced by Lacticaseibacillus paracasei K56 vary significantly under different heat treatments. The treatment at 110 ℃ for 4 s achieves optimal results, enhancing texture and increasing flavor diversity. These findings provide a critical scientific basis for quality enhancement in fermented dairy products.