乳蛋白酶解产物呈味肽序列的研究

Identification of Kokumi Taste Peptides in Hydrolyzed Milk Protein

能够引起味觉浓厚感的物质命名为"kokumi"类物质。通过对乳蛋白酶解得到的水提产物经凝胶柱Sephadex G-15进行分离,得到6个主要组分分离峰(分别命名为P1、P2、P3、P4、P5和P6)。将6个组分分别收集冻干后进行感官评定,选择浓厚感(kokumi)强度最大的P4组分利用反向高效液相色谱(RP-HPLC)进行进一步分离。最后利用基质辅助激光解析电离飞行时间质谱(MALDI-TOF-MS)对RP-HPLC分离得到组分P4中主要呈味肽序列进行测定,分析鉴定得到11个主要由8～9个氨基酸残基组成的肽链,其中大部分肽链来自于β-酪蛋白的酶解产物,并且鉴定得到肽链序列中Glu和Cys的含量较高,与kokumi类呈味肽类物质组分的研究报道相符。

The molecules responsible for food taste perception are defined as ＂kokumi＂ flavor compounds.Sensory evaluation revealed 6 Sephadex G-15 column chromatographic（GPC） fractions（P1,P2,P3,P4,P5 and P6） from hydrolyzed milk protein contained some ＂kokumi＂ flavor compounds,compared to skimmed fresh milk.P4 fraction separated by reversed-phase high performance liquid chromatography（RP-HPLC） exhibited the strongest ＂kokumi＂ sensation.Totally 11 peptides in P4 fraction were identified by matrix-assisted laser desorption/ionization time-of-flight-mass spectrometry（MALDI-TOF-MS）.Most peptides were originated from β-casein.MALDI-TOF-MS also exhibited that Glu and Cys in these peptides were the most important composition related to the ＂kokumi＂ flavor as previously reported.