Manipulating postharvest quality and nutritional content of spinach

The high nutri tional value of leafy salads and convenience to the consumer has resulted in continuing growth of the leafy vegetable market . The shelf -life of leafy vegetables , including spinach, is relatively short (7-14 days) and is influenced by storage conditions. This project investigated the effect of storage temperature and light exposure on quality maintenance during the storage of baby leaf spinach. A series of experiments (Experiment s 1-5) were conducted to conclude that quality loss of spinach leaves is accel erated with increasing temperature and light intensity during storage , temperature having a greater effect (Experiment 5) . Low intensity light, however, improved leaf texture maintenance when compared with samples stored in the dark. In addition to observed responses, results from Experiment s 1 and 2 (reported in Chapter 3) helped to identify leaf textural and visual quality as the best indicators of shelf -life. The f resh produce industry is keen on developing new methods, e.g . pre- storage treatment s that will enhance or maintain nutritional value of the product, retain its colour and texture. There is enough evidence in the literature to s uggest that pre- storage hot water treatment might be a good option. M ost of the studies, however, have been conducted on lettuce . Thus, the decision was made to investigate whether hot water treatment is also a good solution for im proving the quality or extending the shelf -life of baby leaf spinach. Based on the results from Experiment s 6 and 7, it was concluded that hot w ater treatments have limited commercial potential for quality improvement of spinach vii Abstract The high nutri tional value of leafy salads and convenience to the consumer has resulted in continuing growth of the leafy vegetable market . The shelf -life of leafy vegetables , including spinach, is relatively short (7-14 days) and is influenced by storage conditions. This project investigated the effect of storage temperature and light exposure on quality maintenance during the storage of baby leaf spinach. A series of experiments (Experiment s 1-5) were conducted to conclude that quality loss of spinach leaves is accel erated with increasing temperature and light intensity during storage , temperature having a greater effect (Experiment 5) . Low intensity light, however, improved leaf texture maintenance when compared with samples stored in the dark. In addition to observed responses, results from Experiment s 1 and 2 (reported in Chapter 3) helped to identify leaf textural and visual quality as the best indicators of shelf -life. The f resh produce industry is keen on developing new methods, e.g . pre- storage treatment s that will enhance or maintain nutritional value of the product, retain its colour and texture. There is enough evidence in the literature to s uggest that pre- storage hot water treatment might be a good option. M ost of the studies, however, have been conducted on lettuce . Thus, the decision was made to investigate whether hot water treatment is also a good solution for im proving the quality or extending the shelf -life of baby leaf spinach. Based on the results from Experiment s 6 and 7, it was concluded that hot w ater treatments have limited commercial potential for quality improvement of spinach leaves .