Effect of Maceration Time on Micronutrient Concentrations of Canarium schweinfurthii Pulp Flour

Abstract

The effect of wet heat-processing on the micronutrient composition of Canarium schweinfurthii (CS) pulps eaten as traditional snack in most parts of Nigeria was investigated. Fresh wholesome seeds of C. schweinfurthii, obtained from Aba (Abia State, Nigeria) were washed in several changes of distilled water and divided into four lots. The first lot was used raw (CSraw) and the 2nd, 3rd and 4th macerated in water (55ºC) for 15, 30 and 45min to obtain CS15, CS30 and CS45 respectively. CS30 represents sample traditionally processed to accepted cooking tenderness. The raw and wet-heat treated seed pulps, dried for 48hr in air-circulatory oven (50ºC) and milled into flours were evaluated for vitamin and mineral contents using standard methods. The mineral and vitamin contents of the plant food were affected by the processing method. There were progressive increase in the concentrations of Ca, Na, P, Zn, and Pb; and decrease in those of Fe, I, K and Mg as maceration time was increased. The concentrations of Cu, Mn and Se were increased to their peak values and then reduced as the processing time was extended. Highest values were obtained (per 100g sample) for Fe (7.78mg), I (12.0µg), K (11.34mg) and Mg (8.37mg) in CSraw; Ca (21.41mg), Cu (289.33µg) and Mn (4.76mg) in CS15; Na (23.36mg), Se (8.0µg) and Pb (122.67µg) in CS30 and; P (21.33µg) and Zn (1.79mg) in CS45. Vitamins C (2.37mg/100g) and E (1.97mg/100g) were the most abundant vitamins in the sample. The concentrations of all the vitamins investigated increased to their respective peaks values at 15min maceration (CS15) and then, with exception of thiamine, reduced with the extension of the processing time to 45min. It can be concluded that maceration for 15-30mins improves the micronutrient contents of CS pulp.