Effect of prickly pear (Opuntia ficus-indica) and algarrobo (Prosopis spp) pod syrup coatings on the sensory and chemical stability in roasted peanut products

Abstract

The purpose of this work was to determine the oxidative stability of roasted peanuts coated with prickly pear and algarrobo pod syrups. General composition, total phenolic compounds and radical scavenging activity were determined on prickly pear and algarrobo pod syrups. Chemical (peroxide value) and descriptive analyses were performed on samples of roasted peanuts, roasted peanuts with prickly pear syrup and roasted peanuts with algarrobo pod syrup stored at 23 ºC for 112 days to determine protective effect of the syrup coating on the product stability. Prickly pear syrup showed higher moisture, protein, ash, lipid, phenolic compound content and lower carbohydrate content than algarrobo pod syrup. Prickly pear syrup also showed higher antioxidant activity (DPPH Inhibition). Peroxide value, oxidized and cardboard intensity flavors increased and roasted peanutty intensity attribute decreased across the storage time for all studied products. Therefore, the addition of syrup coating provided protection against lipid oxidation. Peroxide value reached 10 meqO2/kg after 8.5 days in roasted peanuts, 20.7 days in roasted peanuts coated with prickle pear syrup and 29.5 days in roasted peanuts coated with algarrobo pod syrup at 23 ºC. In consequence, algarrobo pod syrup had the highest protective effect in the roasted peanut product stored at room temperature.