Impact of two processing methods on the antioxidant, hypolipidemic and hypoglycaemic capacities of Irvingia gabonensis (wild mango) almonds

Abstract

The effects of roasting and boiling on the nutritional value, the chemical composition and some biological activities of Irvingia gabonensis (wild mango) almond-based soups were evaluated. The nutritive value of powders, the polyphenol and flavonoid contents, the antioxidant activities of the aqueous extracts of Raw (RAP), Boiled (BAP) and Roasted then Boiled Almonds Powder (RBAP) were determined. RAP, BAP and RBAP were supplemented at 10% in the diet of streptozotocin-induced diabetic rats for twenty-eight days during which the fasting blood glucose was weekly assayed. Results showed RAP extract exhibiting the highest phenolic (20 mg GAE/g) and flavonoid (17.76 mg GAE/g) contents, as it also presented the best DPPH radical scavenging and FRAP capacities. Boiling and roasting significantly reduced the nutritive value, the phytochemical contents, the antioxidant, hypoglycaemic and hypocholesterolaemic capacities of the almonds powders. RAP better reduced the fasting blood glucose level (59.65%) than BAP (46.6%) and RBAP (34.34%). Furthermore, RAP induced a more significant decrease in triglycerides, total and LDL cholesterol concentrations than did the treated forms. HDL cholesterol was significantly lower in groups treated with BAP and RBAP than in the RAP. Culinary treatments reduced the bioactive properties of Irvingia gabonensis almonds. Boiling alone better preserved these capacities than roasting before boiling.

Keywords

• Irvingia gabonensis
• Culinary treatments
• Antioxidants
• Diabetes mellitus