米酒成分分析與產地鑑定

Component Analysis and Origin Identification of Rice Wines

陳昱棻(Yu-Fen Chen)

指導教授 ： 凌永健

國立清華大學/理學院/化學系/碩士(2014年)

摘要

政府開放民間製酒後，米酒由於製造簡易，成本低廉，以往屢有不肖業者為了增加獲利，造假使用低成本之變性酒精或工業用酒精，做為製酒原料，私釀劣質米酒因此充斥市面，造成消費者飲用後對身體造成負擔；近年來在政府強力緝查和加嚴管制下，毒米酒已不復見，取而代之是使用價廉之米以外來源釀製之酒精，常稱為假酒，難以被人體感官直接分辨，建立完整可靠的假酒鑑定方法，以判定米含量、種類和產地實有其必要性。
本研究第一部分利用固相微萃取法結合氣相層析同位素比質譜儀，測定乙醇的碳13同位素比(δ13C)作為米酒中米含量的判定依據，其中包括：公賣局特級紅標純米酒-29.03‰、日本白鶴山田錦特別純米酒-30.04‰，並根據C3植物如米之13C同位素比應介於-24到-32‰之間，將34件米酒樣品依照乙醇δ13C值判定酒中米含量，包括：(1)小於-25‰ 則米含量高，(2) 介於-25 ‰ 到 -20 ‰ 之間則米含量中等，(3)大於-20‰ 則米含量零之原則，以判定米酒樣品中之米含量。
本研究第二部分是利用分散式液液微萃取法前處理米酒樣品，使用氣相層析質譜儀之全掃描方式，以鑑定米酒中成分，並成功定性57種化合物，使用統計處理氣相層析圖譜，可以區別米酒品牌及產地。

關鍵字

米酒 ； 氣相層析質譜儀 ； 氣相層析同位素比質譜儀 ； 13C同位素比 ； 產地

並列摘要

Since Taiwan government permitted local production of rice wines by private companies, more rice wines with poor quality have been sold in marketplaces. Some rice wines appear in market with fake labels, whereas others might be adulterated, denatured or industrial alcohol, used for profit by cost reduction. Moreover, it is too difficult to distinguish quality of rice wines by human senses. Therefore, it is necessary to develop a reliable method to monitor rice wines sold in marketplaces.
In the first part of this research, we used HS-SPME (headspace- solid phase microextraction) and combined with GC/IRMS (gas chromatograph/isotope ratio mass spectrometer) to measure δ13C of ethanol. According to the literature, rice belongs to C3 plants. Its δ13C should be in between -24 and -32 ‰. Furthermore, we used rice wine from TTL (Taiwan Tobacco & Liquor Corporation) as reference sample, and the 13C value of it is -29.03‰. Thus, we analyzed 34 rice wine samples, and classified them into three groups. (1) δ13C less than -25 ‰ as high rice content, (2) δ13C from -25 ‰ to -20 ‰ as medium rice content, (3) δ13C greater than -20 ‰ as no rice content.
In the second part of this research, we used DLLME (dispersive liquid-liquid microextraction) as pretreatment method and combined with GC/MS (gas chromatograph/mass spectrometer) to identify the components of rice wines. Finally, we determined 57 analytes and obtained gas chromatograms, which could be used to differentiate brands and origins of rice wines.

並列關鍵字

rice wines ； gas chromatograph/mass spectrometer ； gas chromatograph/isotope ratio mass spectrometer ； 13C isotope ratio ； place of origin

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