影響食物中呋喃生成因素之探討

Abstract

呋喃(Furan)為一脂溶性、低沸點且易揮發之液體，其是由食物經熱處理(如工業製程和烹煮過程)後產生。過去研究已指出呋喃對囓齒類動物具有細胞毒性，且在高劑量暴露下對動物具有致癌性。另一方面，根據動物實驗的結果，呋喃亦被國際癌症研究機構(International Agency for Research on Cancer, IARC)列為可能的人類致癌物質。基於上述之毒性，經由飲食攝取呋喃的相關議題逐漸受到重視。 近年來，許多研究開始致力於探討食物中呋喃的毒性、濃度和分析方法；不同的模式系統亦被應用於了解呋喃生成之機制與相關影響因子。為評估其健康風險並降低呋喃暴露，本研究利用田口式方法配合不同的模式系統(包括醣類和抗壞血酸、胺基酸以及多元未飽和脂肪酸等三大類前驅物)進行實驗，將可能影響呋喃生成的因素列入系統中探討(例如：前驅物的種類和含量、加熱溫度以及加熱時間等)；呋喃的生成量則利用頂空固相微萃取技術結合氣相層析質譜儀(Headspace-solid phase microextraction coupled with gas chromatography-mass spectrometry, HS-SPME-GC-MS )進行分析。 結果顯示，加熱溫度和時間對於醣類和抗壞血酸生成呋喃有顯著的影響(p= 0.0006和p= 0.0448)，當加熱的溫度越高或是時間越長，其生成呋喃的量越多；另一方面，多元未飽和脂肪酸生成呋喃的量亦會受加熱溫度之影響(p= 0.0093)，而呈現差異。基於食物安全的前提下，降低加熱溫度與縮短加熱時間可有效地減少相關食物中呋喃的含量；而因呋喃生成機制複雜且影響因素眾多，未來還需更多研究進行探討與釐清。

Furan is a lipophilic and high volatile liquid with low boiling point of 31℃. It may be formed in food under heat treatment, such as the industrial manufacturing and cooking processes. The possible exposure of furan from foods raises concerns because it has been found to cause carcinogenicity and cytotoxicity on animals. Besides, furan is also classified as a possible human carcinogen (Group 2B) by the International Agency for Research on Cancer (IARC) in 1995. Recently, many studies have devoted to research on the toxicity, occurrence and analysis of furan in food. Different model systems were also performed to understand the possible factors and the associated mechanism affecting the formation of furan in foods. For the purpose of assessing health risk and reducing exposures from furan, the main objective of this study was to identify other possible factors, including the varieties and the amounts of precursors, heating temperature and heating time. Taguchi method coupled with model system was employed to find the effects of these factors on furan formation from certain precursors (e.g., sugars and ascorbic acid, amino acids and polyunsaturated fatty acids), respectively. Besides, the technique of solid phase microextraction (SPME) equipped with gas chromatography-mass spectrometry (GC-MS) was performed for the determination of furan. Under the experimental conditions of this study, the results indicated that heating temperature and time might affect furan formation from sugars and ascorbic acid (p= 0.0006 and p=0.0448, respectively). As heating temperature or heating time increased, the amount of furan produced by sugars and ascorbic acid would be increased. Besides, heating temperature also has effect on furan formation by polyunsaturated fatty acids (p= 0.0093). In the premise of food safety, furan formation would be decreased by using lower temperature to cook or sterilize for food containing above components. Shorting heating time may be helpful to reduce furan levels in food fortified with sugars and ascorbic acid as well. Further studies are still needed to clarify the complex mechanism of furan formation in foods.