Preserving traditional leafy vegetables using indigenous knowledge-based drying technologies to improve household food security in Limpopo Province, South Africa.

Master of Science in Agriculture (Food Security)

Collard greens and mustard greens are among several leafy vegetables grown in the Limpopo Province. They are good sources of nutrients and are available in abundance in rural communities. However, they are seasonal and highly perishable limiting their consistent supply and utilisation to contribute to food and nutrition security. Interventions that incorporate indigenous knowledge system (IKS)-based technology for processing, like drying, on traditional food items like the aforementioned traditional leafy vegetables (TLVs) may improve food and nutritional security and livelihood options of, particularly, the predominantly resource-poor rural households. Preservation of the TLVs by appropriate technologies could improve utilisation by availing TLVs off-season and providing an opportunity to earn higher income from the value added TLVs. However, the effects of the proposed preservation technologies on the quality, microbiological safety and consumer acceptability of the TLVs should be assessed. Focus group discussions held with rural and urban participants, provided insights into consumer consumption patterns, perceptions and utilisation of TLVs. The focus group discussions indicated that the green colour of the TLVs was an important quality indicator for perceived high nutritional value. However, the consumption patterns of the TLVs were negatively affected by the stigma attached to the TLVs. Having the TLVs only available in the informal markets, at certain seasons, limited their wider utilisation, especially among the youth and urban consumers, because of no or very limited exposure to the TLVs. The effects of the two preservation methods, the adapted indigenous method of blanching and sun-drying and the modern method of blanching and oven-drying, on the quality and microbiological safety of the TLVs were assessed by monitoring changes in their colour, texture, nutritional composition and microbiological content. The results indicated that the innovative IKS-based method of drying maintained colour better than the modern drying method, however, the opposite was true for texture. The different preservation methods had varying effects on the nutrient content of the two TVLs types. The total microbiological load and composition of the TLVs processed using the two preservation methods were generally within the acceptable limits. Consumer panels of 28 rural and 34 urban dwellers participated in the study to rate the sensory attributes of the differently preserved TLVs on a 5-point pictorial hedonic scale. The rural dwellers found the aroma, texture and colour of sun-dried TLVs more acceptable than oven dried TLVs. Urban residents had differing preferences for the sensory attributes of the two processing methods, but, overall, the sun-dried TLVs were preferred over the oven-dried TLVs. The interfacing intervention of modern and indigenous processing technology was found to be acceptable to the consumers; this has positive implications for improving food and nutritional security and livelihood options of resource-poor rural households.