The papaya (Carica papaya) and Guava (Psidium guajava) are widely grown in the Sudan, where the fruits are usually consumed in fresh form. Many producing areas in the country are known to have a surplus of production which could be wasted because of the seasonality of production, difficulties in marketing and perishable nature of the products.
The objective of the research was the effort to preserve Papaya and Guava fruits by means of canning in forms of slices in syrup, and to determine the effect of canning method on some Papaya and Guava constituents.
White Guava was brought from Food Research Centre experimental farm, while Papaya was brought from Eldamazin Research Station. Canning was done by conventional method with double seaming and heated by steam. The effect of canning method on products quality was evaluated by chemical and organoleptic analysis; there was considerable decrease in vitamin C for Papaya from 43.77 to 18.80 mg/100g, moreover, vitamin C decreased in Guava from 568.77 to 131.27 mg/100g. Acidity decreased for Papaya from 0.2650 to 0.00115, whereas in Guava there was dramatically decrease from 0.45 to 0.17; moreover, reducing sugars showed slightly decrease from 3.90 to 3.60 % and from 5.90 to 5.30 % for Papaya and Guava respectively. The total sugar revealed a significant increase from 4.00 to 9.90 % and from 8.90 to 12.70 % for Papaya and Guava, respectively. Papaya pH was increased from 5.90 to 6.20, whereas in Guava increased from 5.19 to 5.30. Furthermore, TSS showed a highly increase from 3.0 to 11.0 and from 6.0 to 12.0 for Papaya and Guava, respectively.
The effect of canning on products’ quality was also evaluated by organoleptic analysis. Papaya recorded for color 8.1 out of 10, flavor 12 out of 20 and texture 14.7 out of 20. For Guava for color 8.7 out of 10, flavor 16.5 out of 20 and texture 14.2 out of 20. According to these organoleptic results, the color, flavor and texture were well accepted by the panelists.