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

Abstract

BACKGROUND 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. RESULTS 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. CONCLUSION 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

Tailoring the physicochemical properties of starch: impact of integrated ultrasonic and ethanol pretreatment on the oil uptake of infrared fried ginkgo seeds

“…The dense crust that formed at early stage of frying inhibited the migration of internal moisture and subsequently increased the internal pressure and induce large holes and cracks 42 . These large holes would allow more oil to penetrate into the structure, thus increasing oil absorption in fried ginkgo seeds 43 . However, the fried samples with ultrasonic treatmen were observed to have a coarser morphology and smaller holes, with diameters in the range 41–62 μm, and the starch was fully gelatinized, lost its original granular structure and filled in the entire cellular structure after dehydration.…”

“…42 These large holes would allow more oil to penetrate into the structure, thus increasing oil absorption in fried ginkgo seeds. 43 However, the fried samples with ultrasonic treatmen were observed to have a coarser morphology and smaller holes, with diameters in the range 41-62 μm, and the starch was fully gelatinized, lost its original granular structure and filled in the entire cellular structure after dehydration. The gelatinization enthalpy of starch was significantly reduced after ultrasonic pretreatment and the permeability of cell structure was improved, which accelerated crust formation and increased surface roughness.…”

Migration and Distribution of PAH4 in Oil to French Fries Traced Using a Stable Isotope during Frying

“…This was related to the uneven distribution of oil and moisture in the crust and core of the French fries. Li et al 24 found that the oil in French fries was mainly distributed in the crust and the moisture was mainly concentrated in the core. Therefore, the hydrophobic PAH4-d12 mainly migrated into the crust instead of the core.…”

Effects of Steaming on Sweet Potato Soluble Dietary Fiber: Content, Structure, and Lactobacillus Proliferation In Vitro

“…The microcosmic morphology was recorded using an SEM analyzer (Regulus 8100; Hitachi Ltd., Tokyo, Japan) at an accelerating voltage of 3 kV [ 23 ]. The samples were placed on a metal stub with double-sided adhesive tape and sputter-coated with gold in a vacuum sputter coater to make the samples conductive.…”