Impact of Senescence on the Nutritional Profiles of Some Fruits Consume in Makurdi, Nigeria

Chemical and nutritional changes with senescence in some fruits commonly consumed in Makurdi, North Central Nigeria, were investigated using standard analytical methods. Four fruits: mango, pawpaw, orange and pineapple at three different stages of growth; pre-ripe, ripe, and post-ripe were screened for proximate composition, mineral elements, pH, titrable acidity, and vitamins A and C. Results indicated increase in moisture content as the fruit deteriorated in the climacteric fruits (mango and pawpaw), while in the non-climateric fruits (orange and pineapple) the parameter depreciated from ripe to over-ripe. Other proximate parameters showed a consistent rise at ripening and declining thereafter as the fruit deteriorated. In all cases, pH of the fruits showed steady rise with senescence, and this was inversely related to the titrable acidity. Beta-carotene (vitamin A) and ascorbic acid (vitamin C) showed similar trend of peaking at the ripening stages and declining as the fruits aged. Nitrogen recorded the highest concentration (45.28±0.04 mg/L) among the macronutrient elements at the ripe stage of pawpaw, while phosphorus recorded the least (1.39±0.01 mg/L) for over-ripe pineapple. The instrument failed to detect Ni in all samples analyzed in the micronutrient mineral elements category, while Ca recorded the highest (5.25±0.07 mg/L). Macronutrients showed consistency in appreciating at ripening and depreciating as the fruits aged. Only Zn showed presence in all samples among the micronutrients analyzed. Results showed that in most of the parameters investigated, nutritional and chemical contents of the fruits are at their optimum at the ripen stage of the fruits, and declined as the fruits deteriorates with age.