Effect of Two Blanching Methods on the Nutritional Values of Tomatoes and Pumpkin Leaves

Abstract

Various blanching methods were applied to tomatoes and pumpkin leaves (Telfairia occidentalis) to investigate the effect of the  different blanching method on some of its nutritional content. The effects of steam and water blanching as a pretreatment on raw tomatoes and pumpkin leaves (control) were investigated in this study using standard methods. For tomatoes, the %nitrogen, potassium, vitamin A, C and E) mg/100g for raw were;0.48, 68.82mg/100g, 0.88mg/100g, 38.82mg/100g, 0.78mg/100g respectively. 0.45, 69.68mg/100g, 0.58mg/100g, 32.43mg/100g and 0.55mg/100g for water blanched respectively and 0.42, 69.14mg/100g, 0.47mg/100g, 29.66mg/100g, 0.42mg/100g respectively for steam blanching. * For pumpkin leaves, the %nitrogen, potassium, vitamin A, C and E) mg/100g for raw were; 0.98, 46.82mg/100g, 4.63mg/100g, 60.41mg/100g, 0.89mg/100g respectively. 0.95, 46.73mg/100g, 2.38mg/100g,
41.08mg/100g and 0.59mg/100g for water blanched respectively and 0.94, 46.10mg/100g, 1.20mg/100g, 32.16mg/100g, 0.52mg/100g respectively for steam blanching. The results indicate that water and steam blanching significantly reduce the nutritional content. The values of the nutrient were higher in water blanching compared to steam blanching.

Keywords: Fruits, vegetable, steam, water, blanching