Factors Affecting Thermally Induced Furan Formation

Authors: Fan, Xuetong; Huang, Lihan; Sokorai, Kimberly

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/24/2008
Publication Date: 9/24/2008
Citation: Fan, X., Huang, L., Sokorai, K.J. 2008. Factors Affecting Thermally Induced Furan Formation. Journal of Agricultural and Food Chemistry. 56:9490-9494.

Interpretive Summary: Furan, found in a wide range of thermally processed foods including fruit juice, is “reasonably anticipated to be a human carcinogen” according to the U. S. Department of Health and Human Services. It is also known that heating solutions of juice components (such as sugars and vitamin C) produce furan. This study was conducted to investigate effects of heating time and heating temperature on furan formation in apple cider and the effect of pH and phosphate on its formation in solutions of sugars, vitamin C and fatty acids. Our results suggest that significant amounts of furan were produced in apple cider only at higher temperatures (100 Celsius or above) and prolonged treatment time (more than 4 min). The pH and presence of phosphate played significant roles in furan formation in solutions of individual food components. The information will be useful for the food industry to adopt measures that minimize furan formation in thermally processed foods.

Technical Abstract: Furan, a potential carcinogen, can be induced by heat from sugars and fatty acids. However, factors that contribute to its formation in foods are unclear. The objective of this research was to investigate the effects of pH, presence of phosphate, heating time and heating temperature on furan formation. Results showed that little furan was formed by heating fresh apple cider at 90 C for up to 10 min. However, furan formation increased linearly with time at temperatures of 100, 110 and 120 C as heating time increased from 2 to 10 min. Even so, heating apple cider at 120 C for 10 min only induced the formation of about 3 ng/g furan. Heat-induced furan formation from simple sugars, ascorbic acid and linoleic acid was profoundly affected by pH and the presence of phosphate. In general, the presence of phosphate increased furan formation in solutions of sugars and ascorbic acid. In a linoleic acid emulsion, phosphate increased formation of furan at pH 6, but not at pH 3. When ascorbic acid solution was heated, higher amounts of furan were produced at pH 3 than at pH 6 regardless of phosphate’s presence. However, in linoleic acid emulsion, more furan was produced at pH 6 than at pH 3. As a result, the highest amount of furan was formed from the linoleic acid emulsion at pH 6. Our results suggest the importance of high temperature, pH and phosphate in thermally-induced furan formation. The information may help food industry to minimize furan formation in thermally processed foods by altering formulations and processing conditions.