Carob Fruit Polyphenols Reduce Tocopherol Loss, Triacylglycerol Polymerization and Oxidation in Heated Sunflower Oil

Abstract

Heated oils may contain potentially toxic altered compounds. A denatured carob fiber, very rich in non-extractable tannins (Exxenterol Ò ), exhibits antioxidant activities in in vitro experiments. The present study was designed to evaluate in sunflower oil (SO) heated to frying temperature, the protective effect on oil thermal oxidation and polymerization of adding 10 mg Exxenterol/kg oil (SO-10) and 50 mg Exxenterol/kg oil (SO-50). After 2, 8 and 16 h at 180°C, SO displayed a relevant increase in triacylglycerol-derived polar material (PM) and polymer contents and a decrease in a-tocopherol concentrations. Thermal oxidation changes were significantly checked in SO-50 throughout the 16-h heating, while SO-10 only displayed protection from thermal oxidation during the first 2 h of heating. Oil frying-life was doubled because formation of PM and polymers was inhibited by more than 50%. Results clearly show that this non-extractable tanninrich fiber can be successfully employed as an additive to significantly prolong sunflower oil frying-life, and thus decrease the potential toxicity of the heated oil.

Utilization of Carob Fruit as Sources of Phenolic Compounds with Antioxidant Potential: Extraction Optimization and Application in Food Models

“…In the last decade, there have been some attempts to recover phenolic antioxidants from carob fruit using different extraction techniques and solvents [9][10][11]. In addition, researchers have attempted to utilize carob antioxidants to reduce lipid oxidation in cooked pork meat [12], Atlantic horse mackerel [13], and sunflower [14] as well as improve the antioxidant potential in durum wheat pasta [15] and milk beverages [16]. To the best of our knowledge, information about the phenolic composition and antioxidant potency of carob fruit is still obscure as there is no available comparative study on the effect of solvents in extracting phenolic compounds and antioxidant activity.…”

Can Carob-Fruit-Extract-Enriched Meat Improve the Lipoprotein Profile, VLDL-Oxidation, and LDL Receptor Levels Induced by an Atherogenic Diet in STZ-NAD-Diabetic Rats?

“…Now we have focused our attention on the development of a meat product enriched with carob fruit extract (CFE) because we have proven that it has hypoglycemic and hypolipemic properties in healthy animals [ 21 , 22 ]. Likewise, although CFE has been found to reduce oxidative alterations during meat storage [ 23 ], and to work as an antioxidant at frying temperatures [ 24 ], as far as we know, CFE has never been tested as a potential functional ingredient for meat products addressed at improving lipoprotein composition in streptozotocin plus nicotinamide (STZ-NAD) rats as an animal model of diabetes [ 25 , 26 ].…”

Heating and storage of structured acylglycerols with succinyl-linked stigmasterol residue does not cause negative chemical or biological changes

“…There is lack of information on the effects of acyl group position in the glycerol backbone on oxidation and degradation during long term heating at frying temperature. Previous studies have generally compared the stability of oils and fats, which have different fatty acid compositions and positions in glycerol 31 , 32 . The structure of triacylglycerols may be among the most important factors determining their thermal stability.…”