Use of Peroxide Value and Moisture Content as a Measure of Quality for Amaranth-Sorghum Grains Based Complementary Food

Abstract

Amaranth sorghum grains complementary food is a nutrient dense dry food product for infants and young children. It is prone to moisture absorption from the environment and fat oxidation depending on packaging and storage condition due to its low moisture content and high level of unsaturated fat. In this study, amaranth sorghum grains complementary food was stored in three types of packaging material namely, kraft paper, kraft paper with polyethylene lining and aluminium pouch being the commonly used packaging materials for dry complementary foods in Kenya. These packaged samples were stored at ambient, 25°C, 60% relative humidity and 35°C, 75% relative humidity for 180 days. The moisture content of the product and the peroxide value of the oil extracted from the product were determined using the standard methods at an interval of 45 days for 180 days. The initial peroxide value of the product at day zero was 0.48 meq O 2 Kg -1 while its moisture content was 3.7% on dry weight basis. Over the 180 days of storage, aluminium pouch was the most effective package in controlling increase in moisture content and peroxide value in comparison to the other two packages. Samples stored at 35°C, 75% RH had a shorter shelf life compared to those stored at 25°C, 60% RH and ambient conditions. It is recommended that the product should be stored below 25°C and packaged in aluminium pouch to achieve a longer shelf life. Linear equation of a plot of PV (meqO 2 /kg) versus time in days