TITLE:
Vitamin C Degradation Kinetics and Evolution of Titratable Acidity of Nectars from Three Mangifera Cultivars Indica L. during Storage at 4˚C and 37˚C
AUTHORS:
Papa Guedel Faye, Alioune Sow, Oumar Ibn Khatab Cisse, Khadim Niane, Samba Baldé, Omar Toure, Nicolas Cyrille Ayessou, Mady Cisse, Codou Mar Diop
KEYWORDS:
Vitamin C, Mango, Nectar, Acidity, Storage, Degradation, Heat
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.16 No.11,
October
31,
2025
ABSTRACT: Ascorbic acid is a water-soluble molecule essential to the human organism. This vitamin is particularly sensitive to oxidation, due to various factors such as temperature. Furthermore, the titratable acidity not only influences the stability of vitamin C, but also the organoleptic quality of food. Tropical fruits such as mango (Kent variety, papaya, “Dieg Bou Diar” (DBD)) are very popular in the formulation of nectars, due to their nutritional wealth. The objective of this study is to assess the evolution of the vitamin C concentration and the titular acidity in three fruit nectars (papaya, kent, DBD) during storage at 4˚C and 37˚C over 14 days. The content of ascorbic acid was determined by iodometry, a titrimmetric method based on the oxidation of vitamin C by iodine. The titratable acidity was measured by titration. The results reveal a significant decrease in the content of ascorbic acid, more marked at 37˚C, with a maximum loss of 46.4% in the papaya nectar, against 19.5% at 4˚C. The Kent variety has shown the fastest degradation at both temperatures, while the DBD nectar presented better global stability, in particular with stabilization of vitamin C after the ninth day at 4˚C. The papaya nectar has excellent stability at 4˚C, but undergoes marked acidification from the seventh day at 37˚C. Kent nectar, more sensitive to thermal variations, sees its acidity double at 4˚C and increase even more to 37˚C. As for the DBD nectar, it is particularly reactive to temperature, its acidity is multiplied by 2.17˚C to 4˚C and by 3.35˚C to 37˚C, revealing high sensitivity to heat. Thesis works confirm the sensitivity of vitamin C to heat and physico-chemical characteristics of fruit matrices. They highlight the importance of refrigerated storage and varietal choice to preserve the nutritional and technological quality of nectars.