Protein quality of drum-processed cereal–bean–sardine composite supplementary foods for preschool-age children

Acute, severe undernutrition during childhood remains a common health problem in many parts of the world and makes a significant contribution to childhood mortality. This study was conducted to evaluate the protein quality and growth/rehabilitation potential of supplementary foods developed from locally produced materials in Tanzania. Six diets, namely rice meal (RM), bean meal (BM), rice–bean meal (RBM), rice–bean–sardines meal (RBSM), corn–bean–sardines meal (CBSM) and corn–bean meal (CBM), were formulated to maximise the amino acid score as recommended by FAO/WHO/UNU for preschool children. Biological qualities of the diets, including apparent and true protein digestibility, net protein retention ratio, food efficiency ratio, protein digestibility-corrected amino acid score and rehabilitation potential, were evaluated using Sprague Dawley weanling rats. Net protein retention ratio varied significantly (p < 0.05) among control diet (0.93), RBSM (0.92), CBSM (0.86), RM (0.66), RBM (0.44), CBM (0.28), BM (0.12) and corn meal (CM) diet (−0.40). True protein digestibility ranged between 82 and 99%, with BM showing the lowest digestibility. The protein digestibility-corrected amino acid scores were 100% (control diet), 77% (CBSM), 89% (RBSM), 58% (RM), 90% (RBM), 47% (CBM), 85% (BM) and 48% (CM). Two test diets, CBSM and RBSM, showed the greatest potential to support growth and rehabilitation of undernourished rats, while CBM, RBM, BM and CM did not display acceptable growth. These results suggest that cereal–bean–sardine composites are of high quality and have potential for use as supplementary/rehabilitation foods for preschool- and school-age children as well as adults. Copyright © 2004 Society of Chemical Industry