2. Materials and methods
2.1. Raw materials
Red pitaya and guava were purchased from the market in Sri
Kembangan, Selangor, Malaysia. To minimize variation in fruit composition due to source and maturity, they were purchased from the same
lot. Fruits are washed and mashed with a pulper without removing
the skins and seeds in order to maintain the ‘whole fruit’. Proximate
analysis of pulp for moisture content, fat, crude protein, crude fiber,
ash water activity and vitamin C were carried out, and samples were
stored at −20 °C until further used.