Performance of palm olein and modified rapeseed, sunflower, and soybean oils in intermittent deep‐frying

Abstract

The frying performance of rapeseed, soybean, and sunflower oils with modified fatty acid composition, and palm olein (PALMO) was compared during a rotational frying operation. The frying was conducted at 185 ± 5°C for 6 days where French fries, battered chicken, and fish sticks were fried in succession. At the end of the frying period, high‐oleic rapeseed and sunflower oils exhibited a significantly higher frying stability than PALMO and other modified oils, based on total polar components (TPC), polymers, and non‐volatile carbonyl compounds formation (anisidine value (AV)). The rate of TPC formation was 2.9, 2.9, 3.2, 3.2, and 3.4% per frying day for high‐oleic low‐linolenic rapeseed (HOLLRAP), high‐oleic sunflower (HOSUN), mid‐oleic sunflower (MOSUN), low‐linolenic soybean (LLSOY), and PALMO, respectively. Although the contents of free fatty acids (FFA) in the used oils were significantly below the regulatory discard level, in PALMO formation of these compounds was 1.7 times higher compared to the modified oils. Color component formation and tocopherol degradation were also observed to be the highest in palm olein. A 15‐member consumer panel awarded HOLLRAP and HOSUN the highest overall sensory acceptance scores, while for LLSOY and PALMO the lowest. Practical applications: Although several frying oils are available in today's market, only a few of them can deliver satisfactory performance during extended frying operation. Thus, the search for the ideal frying oils/fats is an ongoing task. The present study assessed frying performance in the quest for the appropriate frying oils/fats in order to deliver healthy fried products with optimized nutritional qualities.

Rancimat Test for Measuring the Oxidative Stability of Cooking Oils Upon Prolonged Frying: Short Communication

“…This can be explained from the basis of significant level of tocotrienols in POo that constitutes more than 70% of the total vitamin E content. The presence of three double bonds at the side chain of tocotrienols makes them more susceptible to deterioration when exposed to excessive heat in comparison to their tocopherols counterpart (Aladedunye and Przybylski, 2014). Interestingly, a balance proportion of POo with SBO and CNO, respectively and a tertiary blend containing POo, SBO and CNO gave identical depreciation rate with that of their unary form; this however is not true for binary blend of 50% SFO.…”

Feasibility of Continuous Frying System to Improve the Quality Indices of Palm Olein for the Production of Extruded Product

“…25 ; Belgium, Argentina and Chile 2.5 ; and Panama 3 22 . Assuming 1 of FFA is taken as the bench mark, it is conjectured that palm olein, in the case of intermittent frying, can be utilised for another 4 days before discarded.…”

“…three double bonds at the side chain of tocotrienols is prone to degradation in comparison to their tocopherols counterparts 25 .…”

“…This can be elaborated from the spectrum of non-volatility of the polar compound fractions -i.e. polymerised and oxidised TAG, DAG and FFAdeveloped during excessive heat treatment 25 . Oils containing high level of polar compounds are potentially toxic and can be easily absorbed by human body 27 .…”

“…Palm olein appeared to be darker 21.2 R when potato chips were continuously fried for 56 h Ahmad Tarmizi and Ismail, 2014 . The incidence of colour reversion in palm olein can be explained from the perspective of its inherent antioxidants content; trace pigments, tocopherols and particularly tocotrienols are susceptible to the formation of red-brown quinone polymer which can further cause oil colourisation upon exposure at elevated temperatures 25 .…”