Effect of deep-fat frying on ascorbic acid, carotenoids and potassium contents of plantain cylinders

The influence of thermal treatment (frying of plantain) on the micronutrients ascorbic acid, potassium and carotenoids is evaluated. Cylinders (diameter 30 mm, thickness 10 mm) of plantain (Musa AAB 'barraganete') were fried at four thermal treatments (120-180[degrees]C and from 24 to 4 min) to obtain products with approximately the same water content ([approximately equal to] 0.8 [+ or -]0.02 kg/[kg.sup.1]) and fat content ([approximately equal to] 0.15 [+ or -]0.06 kg/kg). The thermal study used the cook value and the mean cook value as indicators of the effect of several different treatment temperatures and times on quality. Deep-fat frying had no significant effect on carotenoid contents at any frying conditions, and on potassium content, except at 120[degrees] C and 24 min (loss [less than or equal to] 11%). There was a significant, but not complete, loss ([less than or equal to] 45%) of ascorbic acid. The process with the greatest effect was low temperature and long time (120[degrees] C/24 min), as observed for potassium and ascorbic acid. These results are in agreement with other studies that demonstrated short thermal treatments at high temperatures protect food nutritional quality, as shown by the cook value and the mean cook value. In our work, deep-fat frying of plantain preserved most of the micronutrient contents that were evaluated. Keywords: Deep-fat frying, ascorbic acid, carotenoids, potassium, plantain