Nitrogen Fertilization And Storage Temperature Effects On The Nutritive Value Of Solanum Nigrum

Summary

The effects of four levels of nitrogen fertilization, three storage temperaturesand three methods of dehydration on the nutritive value of Solanum nigrum(Solanaceae) were investigated in field and laboratory experiments. Theascorbic acid content of S. nigrum increased only with the first addition of 60 kg N/ha while the crude protein content continued to increase with eachaddition of N. Nitrogen application resulted in slight decreases in Ca, Mg, P andKin the vegetable at time of harvest but increased with length of storage time.Storage of the vegetable at 25-28 °C for four days resulted in rapiddeterioration in quality, especially the ascorbic acid. However, when stored atcooler temperatures ranging between +4 °and - 6 °C, most of the qualityfactors determined were preserved throughout the four-week duration of thestorage treatments. There was no significant difference between storing thevegetable at +4 ° and storing it at - 6 °c. Drying leafy vegetables in the sun orin mechanical driers resulted in rapid decreases in ascorbic acid content buthad no significant effects on crude protein and mineral nutrient content.