Insight into the effect of fatty acid composition on the texture of French fries.

Abstract

Several researchers have reported that the texture of fries is affected by the fatty acid composition of oil, although the mechanism of this effect is not clear. In this regard, fries were fried in refined rapeseed oil and fully hydrogenated rapeseed oil with diverse proportions (0%, 20%, 40%, 60%, 80% and 100%) and were analyzed based on the content of moisture and oil, texture, thermal properties, crystalline properties and microstructure. The outcomes presented that fries fried in fully hydrogenated oil had less oil absorption and moisture loss than those fried in refined oil. The results from the texture analyzer, differential scanning calorimetry and X-ray diffraction showed that hardness, enthalpy and relative crystallinity increased with an increase in the proportion of fully hydrogenated oil. However, the peaks of starch-lipid complexes were hardly observed during frying. Furthermore, scanning electron microscopy results displayed that some physically trapped fat was observed in fries fried in mixed hydrogenated oil. Stereomicroscope images showed that the crust thickness of the fries increased slightly with an increase in the proportion of fully hydrogenated oil. Overall, the upsurge in crust thickness and oil crystals was responsible for an increase in the hardness of the fries. This indicated that the texture of fries can be manipulated by altering the fatty acid composition of the oil. © 2021 Society of Chemical Industry.