Preservation of Chayote (Sechium Edule L) Using Different Drying Methods

Abstract

Chayote (Sechium edule L) has a short shelf life due to its high moisture content (87-95%). This study aimed at prolonging the shelf life of chayote by using different drying methods: convective hot oven drying (OV), and osmo-dehydration (OD) with salt or sugar. Dried samples (at 20% moisture content) were analysed for their nutritional, rehydration, textural and sensory properties. Dried chayote was stored for three months while determining total plate count (TPC), coliforms, Staphylococcus, yeasts and moulds and sensory acceptability. The time to attain 20% moisture in chayote varied significantly (p < 0.05) from 9 h (OV and OD sugar) and 12h for osmo-dried chayote in salt. Ash, total sugar, starch and fiber increased significantly (p ˂ 0.05) from fresh sample as follows 5.2 - 28.3 g/100g (OD salt), 5.8 - 18.5 g/100g (OD sugar), 18.4 - 21.3 g/100g (OD sugar), 49.1 - 52.9 g/100g (OD sugar), respectively after drying. Vitamin C decreased from 232.5 - 38.4 mg/100g (OV) whereas zinc decreased from 1442.9 - 29.5 mg/100g (OV). Rehydration ratio varied from 2.0 ± 0.26 (OD salt after 30 min) to 2.9 ± 0.05 (OV after 20 min). Osmotically dehydrated samples were softer than air dried samples after rehydration and cooking. Total plate counts decreased from log 5.14 to non-detected. Staphylococcus aureus counts decreased from log 4.29 to non-detected. Coliform counts deceased from log 4.91 non detected respectively. Osmotic dehydration contributed to the preservation of the nutritional, textural and sensory properties of dried chayote with salt achieving better preservation than sugar. Drying increased the shelf life of chayote from days to three months with high microbial quality and sensory acceptability.