基于快速气相色谱电子鼻研究超高压射流处理脱脂乳的感官品质

Quality Evaluation of Skimmed Milk Treated with Ultra-high Pressure Jet Using Fast Gas Chromatography-Based Electronic Nose

以新鲜脱脂乳为原料,探究超高压射流(ultra-high pressure jet,UHPJ)处理对脱脂乳感官品质的影响。脱脂乳经100~300 MPa UHPJ处理后,采用电子眼、电子鼻、感官评价分别检测脱脂乳颜色、气味及综合风味变化。结果表明:脱脂乳的主要色号以4095白色为主,占比46.80%~53.83%;电子鼻共检测到酯类、酮类、醛类等42种挥发性风味成分,大部分风味成分呈乳香、果香、烘烤香、青草等气味,主成分分析结果显示,300 MPa处理脱脂乳样品和其他样品风味相差较大;感官评价结果显示,UHPJ处理脱脂乳的乳香和甜味较为突出,不同样品之间在甜味、蛋白胨味、铁锈味、烧焦味和寡淡味方面差异明显,250、300 MPa处理样品生成的二甲基硫等硫化物能够显著增强脱脂乳的烧焦味、蛋白胨味。综上,200 MPa UHPJ处理能较完整地保留脱脂乳中的风味成分,进而实现原料乳风味的保持。

This study explored the impact of ultra-high pressure jet(UHPJ)treatment on the quality of fresh skimmed milk.After UHPJ treatment at pressures ranging from 100 to 300 MPa,the changes in the color,odor and overall flavor of skimmed milk were detected by using electronic eye,electronic nose and sensory evaluation.The results showed that the main color number of skimmed milk was white 4095,constituting 46.80%–53.83%.A total of 42 volatile flavor components such as esters,ketones,and aldehydes were detected by electronic nose.The majority of the flavor components exhibited milky,fruity,roasted,and grassy aromas.Principal component analysis(PCA)revealed that the flavor of samples treated at 300 MPa differed greatly from that of other treated samples.Sensory evaluation indicated that among the flavor attributes evaluated,milky aroma and sweetness were prominent,and there were considerable differences between different samples in terms of sweetness,peptone-like,rusty,burnt and bland flavors.Samples treated at 250 and 300 MPa generated sulfide compounds such as dimethyl sulfide that significantly enhanced the burnt and peptone-like flavors of skimmed milk.In conclusion,UHPJ treatment with 200 MPa can better retain the flavor components in skimmed milk and consequently maintain the flavor of raw milk.