Phenolic extracts of coconut oil cake: a potential alternative for synthetic antioxidants

Abstract

Limitations of natural antioxidants include relatively low antioxidant activity, narrow range of food systems where the antioxidants are effective and limited thermal stability compared to synthetic antioxidants. In the present study, the phenolic extract of coconut oil cake (COCE) was tested for antioxidant activity-related food stabilization. Heat stabilities of COCE and synthetic antioxidants were determined by measuring the induction time of sunflower oil enriched with heat-treated antioxidants. In the β-carotene-linoleate emulsion used for testing antioxidant activity, COCE can retain 96 ± 2% of initial colour intensity while BHT can retain 89 ± 2% of initial colour intensity at 60 µg mL -1 concentration after two hours. TBARS contents (MDA equivalents / kg of meat) in COCE-treated and control pork samples after 14 days was 2.80 ± 0.57 and 22.55 ± 2.30 respectively. Heat stability varies in the order butylated hydroxytoluene (BHT) < (butylated hydroxyanisole (BHA) < COCE < tertiary butylhydroxyquinone (TBHQ). The results of these experiments suggest that COCE is a versatile and thermally stable natural antioxidant mixture effective in stabilizing many food systems.Keywords: coconut oil cake; antioxidants; polyphenols; DPPH; food model systems.Practical Application: Ethanolic extracts of coconut oil cake can improve the shelf life of food emulsions, meat and polyunsaturated oils. Phenolic antioxidants responsible for these food stabilizing effects are highly thermally stable. Therefore, the extracts of coconut cake can be developed as commercial natural antioxidant preparations with potential applications in food industry.

Phenolic extracts of the leaves ofPsidium guineenseSw. improve the shelf life of sunflower oil and baked cake and antioxidant status of Wistar rats

“…Then they were ground using a kitchen grinder, sieved through a 180‐µm mesh and kept at −20°C until further analysis. Ethanol:water (70:30 v/v) solvent system (1.0 mL) was mixed with the leaf powder (0.2 g) and phenolic antioxidants were extracted according to a reported method (Seneviratne, Withanage, & Jayawardena, ). Four successive extractions were performed with the solvent system (1 mL).…”

Improvement of Oxidative Stability and Microbial Shelf Life of Vanilla Cake by Coconut Oil Meal and Sesame Oil Meal Phenolic Extracts

“…Ethanol:water (70 : 30 v/v) solvent system (1.0 mL) was mixed with the powder of the oil meal (0.2 g), and total phenol contents of the meal extracts were determined using Folin Ciocalteu reagent as described earlier [12]. DPPH radical scavenging assay, ferric reducing antioxidant power (FRAP) assay, and deoxyribose degradation assay were performed as described by Seneviratne and Kotuwegedara [13] at 30 μg/mL concentration of phenolic substances.…”

“…DPPH radical scavenging assay, ferric reducing antioxidant power (FRAP) assay, and deoxyribose degradation assay were performed as described by Seneviratne and Kotuwegedara [13] at 30 μg/mL concentration of phenolic substances. Antioxidant activity in egg yolk homogenate was determined according to a previously reported method [12].…”

Effect of chain length and saturation of the fatty acids in dietary triglycerides on lipid metabolism in Wistar rats

“…Phenolic compounds were extracted to ethanol:water (70:30 v/v, 2.0 ml) by mixing the powder (2.0 g) using a vortex at 40 Hz for 2 min (twice) and centrifuged at 400 ×g for 10 min. Four successive extractions were performed for each sample and resultant extracts were diluted to 10.0 ml (Seneviratne et al, 2016). Total phenol content was determined based on a reported method (Singleton & Rossi, 1965).…”