Vegetable quality can be influenced by various factors such as genotypic differences, pre-harvest conditions, cultural practices, stage of maturity, harvesting methods and postharvest handling procedures as well as the interactions among these factors. The research was aimed at determining variation in nutrient content of the spinach and lettuce during growth and maturation period. The Seeds were planted and analyzed for proximate, mineral and vitamin content at the age of 3, 5 and 7 weeks to observe the variation. Proximate composition for the spinach and lettuce samples shows a decrease with an increase in age of the leaves (3wks -7wks) except for carbohydrate content which increase with increase in age, The minerals analysis of the leaves showed zinc, iron and copper decrease with increase in age while calcium and magnesium increase with increase in age. There is high amount of retinol (vitamin A), and ascorbic acid (vitamin C) in both leaves at week 3 while the content decrease with increase in age. It is concluded that most of the proximate, mineral and vitamin contents used to decreases with an increase in growth period, therefore young leaves are more nutritious than fully matured leaves.
Seldimirova et al. (Mon,) studied this question.