Three mature disease-free plants of each cultivar were identified by a qualified agronomist and marked. When the fruits of the identified bunch for each plant and cultivar were mature (deep green, full and rounded), the bunch was harvested and 2nd and 3rd hand, each containing between 12 and 16 fingers, were picked and labeled. The samples were packed in an aerated carton and transported by road to Kampala, arriving within 48 h of harvest. On arrival at Kampala, the fruit samples were allowed to ripen naturally in a well aerated room. The ripening stages of interest in this study were stages 1 (unripe) and 5 (ripe). These indices are based on peel color: 1 = green; 2 = green with trace of yellow; 3 = more green than yellow; 4 = more yellow than green; 5 = only green tips remaining; 6 = all yellow; 7 = yellow flecked with brown (Stover and Simmonds, 1987). Three fingers from different plants of each cultivar were randomly detached from the banana hands at ripening stage 1, cleaned, hand peeled, quartered, each of the 4 quarters forming a finger were pooled into one
sample and put in labeled zip-lock bags with air removed manually and frozen at 20 8C to await lyophilization. The rest of the hand was left to ripen naturally in a well-aerated room. Sub-sampling of each cultivar for ripening stage 5 was done when the fruit peel was all yellow with only green tips, and the procedures applied during stage 1 were then followed.