Effects of repeated deep-frying on fatty acid profiles of potato fries and frying oils: soybean oil, canola oil and their 1:1 blend
https://doi.org/10.31246/mjn-2020-0011
- Author:
Michelle Ting Yun Yeo
1
;
Xinyan Bi
1
;
Christiani Jeyakumar Henry
1
,
2
Author Information
1. Clinical Nutrition Research Centre (CNRC), Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), Singapore&
2. Department of Biochemistry, National University of Singapore, Singapore
- Publication Type:Journal Article
- Keywords:
Deep frying, reused oil, fatty acid, potatoes
- From:
Malaysian Journal of Nutrition
2020;26(No.3):389-399
- CountryMalaysia
- Language:English
-
Abstract:
Introduction: This study looked at the fatty acid composition changes in potato
fries fried in three different types of oils, namely soybean oil (SO), canola oil (CO),
and a 1:1 blend of soybean oil and canola oil (SCO), throughout an intermittent
frying process of 80 batches in five consecutive days. The study also examined the
fatty acid composition changes in SO, CO and SCO during the frying process. Methods: Fat from potato fries (extracted by Soxtec system) and oil samples from the
corresponding frying oil were analysed by gas chromatography-mass spectrometer
(GC-MS) to examine the fatty acid profile changes during the deep-frying process.
Results: Linoleic acid (LA) and a-linolenic acid (ALA) in all three oils decreased,
while oleic acid (C18:1), stearic acid (C18:0), palmitic acid (C16:0) and octanoic acid
(C8:0) increased. Formation of C18:1 trans fatty acid was observed as the frying
time increased. The fatty acid composition of the potato fries was consistent with
the fatty acid composition of the corresponding frying oils. Conclusion: Our results
showed that blending soybean oil and canola oil did not significantly improve the
frying stability of the resulting oil in terms of fatty acid profile. Due to the formation
of trans fatty acids and the decrease in polyunsaturated fatty acids, our study also
recommends not to use the same frying oil repeatedly and not to consume food
products cooked in reused oil.
- Full text:4.2020my0509.pdf
