A Comparative Study on Formation of Polar Components, Fatty Acids and Sterols during Frying of Refined Olive Pomace Oil Pure and Its Blend Coconut Oil

Abstract

The frying performance of pure refined olive-pomace oil (ROPO) and blended with refined coconut oil (RCO) (80:20) was compared during a frying operation of French fries at 180 °C. Blending polyunsaturated oils with highly saturated or monounsaturated oils has been studied extensively, however in literature there is no study has been reported so far on blending ROPO (rich in monounsaturated fatty acids) with RCO (rich in saturated fatty acids) to formulate new frying oils. At the end of the frying process, the blend of ROPO/RCO exhibited a higher chemical stability than the pure ROPO based on total polar compounds (TPC), and polymers. The rate of TPC formation was achieved 23.3% and 30.6% for the blend and the pure oil, respectively. Trans and free fatty acids content, as well as anisidine value were also observed to be the highest in the pure ROPO. This study evaluated the frying performance in the search for appropriate frying oils to deliver healthy fried products with optimized nutritional qualities.

Comparative study of polymers and total polar compounds as indicators of refined oil degradation during frying

“…The fatty acids identified were palmitic acid (C16:0), stearic (C18:0), oleic (C18:1), linoleic According to our previous results [14], the data showed that the amount of PUFAs such as the linoleic and linolenic acids decreased gradually after 60 sessions of frying in both oils (ROPO pure and ROPO/RCO) ranging between 16.95% and 0.64%, respectively, whereas, varying between 12.94% and 0.40%, respectively. Consequently, a relative increase in the percentages of SFAs such as the palmitic acid was observed.…”

“…Blending the polyunsaturated oils with more saturated or monounsaturated oils is a potential solution to improve oil stability [14].…”

“…In fact, the lowest value of C16:0 was observed for the ROPO pure with 17.24%, while the highest one for the blended oil with 20.87% after 60 sessions of frying. Many countries have established regulatory limits for TPC in frying oils and considered 25% or 16% polymers as limits [14,24].Based on the rapid measurements of TPC using the Testo 270, results revealed that both the duration of heating and the nature of oils affect the total polar compounds ( Table 2). Initially, the TPC level in the pure ROPO and blend ROPO/RCO was 9% and 9.5%, while the content of polymeric compounds was 1.9% and 0.9%, respectively.…”

“…Oils with high levels of polyunsaturated fatty acids (PUFA) are not proper for frying due to their fatty acid composition, with a higher tendency to oxidation [4,11,13]. Blending is one of the strategies used to enhance the frying stability [12,14], which improves oil functionalities and adjusts the fatty acid profile to optimal levels for frying applications.…”

Physiochemical properties of short‐term frying oil for chicken wing and its oxidative stability in an oil‐in‐water emulsion

“…PUFA is known to play a crucial role in human nutrition by preventing health disorders. Because palmitic acid is more stable against oxidation, whereas linoleic acid is more susceptible to oxidation, the C 18:2n6 /C 16:0 ratio may be an effective indicator of the degree of edible oil deterioration (Hammouda, Triki, Matthäus, & Bouaziz, 2018;Zribi, Jabeur, Matthäus, & Bouaziz, 2016). Additionally, palmitic acid level was increased after frying, which has been reported by Bansal et al (2010), who revealed that oxidative deterioration of linoleic acid under hightemperature condition led to the formation of palmitic acid.…”