Frying performance of a sunflower/palm oil blend in comparison with pure palm oil

Abstract

The aim of this study was to test the performance of a vegetable oil blend formulated as alternative to pure palm oil as frying medium. For this purpose, the evolution of many analytical parameters (free acidity, spectrophotometric indices, total polar components, fatty acid composition, short-chain fatty acids, tocopherol and tocotrienol content and composition, color, flavor evaluated by means of an electronic nose) of the selected blend (sunflower/palm oil 65 : 35 vol/vol) has been monitored during a prolonged frying process (8 h discontinuous frying without oil replenishment) in comparison to pure palm oil. Sensory attributes of the fried food were also evaluated. The blend proved to keep qualitative parameters comparable to those shown by palm oil during the prolonged frying process. Even if some oxidation indices, such as spectrophotometric indices, short-chain fatty acids and total polar components, increased faster in the blend, it showed a higher tocopherol content and a lower increment in free fatty acids as compared to pure palm oil. Chips fried in the two oils did not show significantly different sensory profiles.

Efecto de la Temperatura y Tiempo de Fritura sobre las Características Sensoriales del Ñame (Dioscorea alata)

“…En la figura 3 se aprecian los cambios en el contenido de la grasa durante la fritura, la grasosidad toma valores muy pequeños (menor a 1) a temperaturas bajas y a medida que se forma la costra la grasosidad disminuye más hasta valores cercanos a cero. Esto se debe a la deshidratación de las células internas y parte del agua evaporada, la cual es remplazada parcialmente por el aceite de fritura (De Marco et al, 2007). Sin embargo durante la fritura el vapor producido dentro del producto genera un gradiente de presión entre la estructura interna de este y la superficie externa, evitando que el aceite ingrese al interior y se adhiera a la superficie.…”

Effect of frying on the rheological and chemical properties of palm oil and its blends

“…Since it has been showed that during a prolonged frying process, the fatty acid composition in oil undergoes modifications due to polymerization, as well as pyrolytic, hydrolytic and oxidative reactions also take place (Frankel 1998;Márquez-Ruíz and Dobarganes 2007). However, the researchers have stressed that the evaluation of the resistance to oxidation does not take into account the presence of natural antioxidants in oils (tocopherols and tocotrienols) nor the initial composition of fatty acids (Marco et al 2007). The 2922 cm −1 and 2855 cm bands are due to the symmetric stretching of CH 2 groups.…”

Quality Assessment of Palm Products upon Prolonged Heat Treatment

“…As their thermal stability is concerned, palm oil and its fractions, mainly palm olein (singlefractionated), double-fractionated palm olein, red palm oil/olein and palm stearin are widely utilised in frying activities, including continuous frying 2) . These products demonstrate inherent frying properties, which is often regarded as a heavy duty frying oil with stronger resistance toward thermo-oxidation than most of the other vegetable oils and fats 3,4) . Apart from that, the availability of both palm oil and palm fractions at competitive prices also contributes to the wide usage of these products for frying purposes.…”