The Recovery of Used Frying Oils With Various Adsorbents

Abstract

The recovery of used frying oils is of commercial and economic importance. One additional reuse of recovered oil could provide considerable savings to the food processors. Seven commonly used filter aids: Silasorb, Britesorb, HB 600, Purifry, Frypowder, Activated Carbon, and Magnesol, as well as two commercially unavailable adsorbents, Sorbead AF and Calsilite were studied. A number of AOCS official methods were used to evaluate their adsorptiveness, free fatty acids (FFA), conjugated diene value (CDV), total polar components (TPC), oxidative stability index (OSI), color and viscosity (V). High performance size exclusion chromatography was employed to determine the amount of polymers and low molecular weight compounds. When heated to 150C prior to filtration, HB 600 was found to reduce FFA content by 84.5%. Frypowder improved oil stability by 38.3%, and Magnesol lightened oil color by 46.3%. After statistical analysis of the data, five of them were selected, two or three of which were blended to obtain the most effective combination. The blending of HB 600 and Magnesol reduced FFA and TPC by 90.8–93.7% and 6.0–17.8%, respectively, and improved oil stability by 23.4–24.7%. The adsorbent combinations have potential for use in practical frying operation to improve the functional and healthy aspects of used frying oils.

Effect of Lavender and Thyme incorporation in sunflower seed oil on its resistance to frying temperatures

“…The released fatty acids are more susceptible to thermal oxidation under frying temperatures. The oxidized products of fatty acids give the off-flavors and odors (hydrolytic rancidity) to the frying medium and fried foods (Lin, Akoh, & Reynolds, 1998;Nawar, 1996). Therefore, controlling the level of FFA within a reasonable range would prevent the breakdown of fats.…”

“…The oil may thicken and become more viscous as it is heated. This seems to be due to the process of polymerization and also to oxidation, hydrolysis and isomerization (Lin et al, 1998). During frying process, the oil is really a heat transfer medium.…”

Impact of Frying on Fatty Acid Profile and Rheological Behaviour of Some Vegetable Oils

“…The oil may thicken and become more viscous as it is heated. This seems to be due to the process of polymerisation and also to oxidation, hydrolysis and isomerization [8]. It is a serious performance fault because it causes a number of problems.…”

Microstructure of Activated Charcoal from Coconut Shell as Consumables Oil Refining

“…Karena gugus peroksida dalam dosis yang besar dapat merangsang terjadinya kanker kolonsiklik (Suirta, 2009). Lin et al(1998) melakukan penelitian dengan campuran absorben yang terdiri 4.5% clay (tanah liat), 0.5% charcoal (arang), 2.5% MgO, 2.5% celite dapat menurunkan asam lemak bebas sebesar 74%. Widayat et al (2006) telah melakukan penelitian peningkatan kualitas minyak goreng dengan zeolit dan terjadi pengurangan bilangan asam dan hasilnya menunjukkan bilangan asam sebesar 1.71%.…”