Effects of Maturity on the Proximate Composition of Lettuce (Lactuca sativa)

Abstract

The effects of maturity on some proximate compositions of lettuce are reported in this study. Samples of lettuce (Lactuca sativa) were collected from a lettuce grower at “Chanchaga” in Minna, Niger State, Nigeria 50, 60 and 70 days after transplanting (DAT). For each of the stages of maturity the samples were analysed for carbohydrate, fat, protein, fibre, ash, moisture, vitamin C and beta carotene contents using techniques adopted from various standard methods. All analyses were done in triplicates. A one- way ANOVA was used to analyse the data obtained. The average value of carbohydrate (11.44±0.66%) obtained from the samples harvested 50 DAT was significantly higher (p≤ 0.05) than those harvested 60 and 70 DAT. The average values of all the assessed proximate compositions of the lettuce harvested at the three different maturity stages showed significant variations (p≤ 0.05) but the trends in these variations differed from one parameter to the other. The protein and fat contents of the assessed samples showed a clear increase in values as the harvest days after transplanting increased, the other parameters do not have a clear pattern variation among the three different maturity stages investigated. It is then concluded from this study that proximate composition of lettuce is actually influenced by the stage of maturity at harvest. However, the variations have no definite pattern, while in some parameters the values increased with increase in stage of maturity, others do not have definite pattern in the changes