紫色马铃薯全粉加工的汁液腥味物质成分及酶解脱腥效果

Off-flavor compounds of liquid from processing purple potato granules and enzymatic deodorization effect

[目的]明确冻融分离法制备紫色马铃薯全粉汁液副产物腥味物质成分,及其酶解脱腥效果。[方法]采用顶空固相微萃取气相色谱质谱联用法结合气味活度值法,分析加工中间样品、汁液副产物及γ淀粉酶酶解汁液的挥发性物质组成变化。[结果]冻融分离法制备紫色马铃薯全粉过程中样品风味及其挥发性物质成分组成变化明显。从生鲜薯片、熟化薯片、解冻薯泥、分离汁液和酶解分离汁液中分别鉴定出16种(醛类和醇类为主)、27种(醛类、醇类和酚类为主)、18种(醛类和帖烯类为主)、33种(醇类和酚类为主)和39种(醛类、醇类、酮类和酚类为主)挥发性物质。来源于生鲜薯片中的1辛烯3醇是形成汁液土腥味的关键物质,熟化阶段形成的顺3壬烯1醇和吲哚分别是汁液酸腐气味和刺激性气味的主要成分。γ淀粉酶酶解处理可有效消除汁液中的3种致腥成分,同时新生成苯乙醛、壬醛、癸醛、月桂醛、大马士酮、香芹酚等关键性呈香物质,以及吡嗪类、噻唑类杂环芳香气成分。[结论]γ淀粉酶酶解处理可有效脱除紫色马铃薯汁液腥味。

【Objective】To identify the off-flavor compounds of liquid by-product from processing purple potato granules using freeze-thaw method,and study the enzymatic deodorization effect.【Method】Changes of volatile components in partially processed samples,liquid by-product and γ-amylase hydrolysate were analyzed using head space solid phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPMEGC- MS).【Result】Significant differences were found in the sensory flavor and volatile components during the process of freeze-thaw separation of purple potato granules.We identified 16(mainly aldehydes and alcohols),27(mainly aldehydes,alcohols and phenols),18(mainly aldehydes and terpenes),33(mainly alcohols and phenols) and 39 (mainly aldehydes,alcohols,ketones and phenols) kinds of volatile compounds from fresh potato chips,steamed potato,thawed and mashed potato,separation liquid and γ-amylase hydrolysate,respectively.The key substance from fresh potato chips was 1-octen-3-ol leading to the earthy smell of separation liquid.The main substances formed in steaming process were cis-3-nonen-1-ol and indole leading to sour smell and irritant odor of separation liquid respectively.γ-Amylase hydrolysis effectively removed the three odorants in separation liquid and increased the contents of aroma components including benzadehyde,aldehyde,decyl aldehyde,lauryl aldehyde,damascene,carvacrol and heterocyclic compounds such as pyrazines,benzothiazole.【Conclusion】γ-Amylase hydrolysis can effectively remove the off-flavor of liquid by-product from purple potato granules.