Mango soy fortified yoghurt (MSFY) powder was obtained after recirculatory convective drying, conditioning and grinding and was packaged in pouches of high density polypropylene (HDPP) and pouches of aluminium laminated polyethylene (ALP) pouches. The shelf life of MSFY powder was predicted on the basis of free flowness of product under accelerated storage condition (38 +/- 1 degreesC, 90% relative humidity) and was calculated to be 45 and 54 days in HDPP and ALP, respectively. The storage stability of MSFY powder in terms of quality parameters free fatty acid (FFA), thiobarbituric acid (TBA), hydroxymethyl furfural (HMF), starter counts and colour change was studied in both packaging materials. The magnitude of quality change of MSFY powder measured during storage suggests that ALP was better than HDPP. The kinetics of quality parameter change was of zero order. (C) 2004 Elsevier Ltd. All rights reserved.