ABSTRACT
ABSTRACT: This research evaluated the influence of blanching on osmotic dehydration in sucrose solutions of papaya of Formosa cultivar. The characterization of invertase present in the fruits was also done. Blanching possibly caused damages to the cellular structure resulting in higher water loss, sugar gain and, thus, effective diffusion coefficients than fresh papayas during osmotic dehydration. The invertase extracted from papaya pulp presented optimum temperature of 45 °C and optimum pH of 4.8. Considering the low production cost of papaya and the invertase characteristics, the fruit shows to be a potential source for the referred enzyme extraction.
RESUMO: O objetivo desse trabalho foi avaliar a influência do branqueamento na desidratação osmótica de mamão Formosa em soluções de sacarose. A caracterização da invertase presente nos frutos também foi realizada. O branqueamento possivelmente danificou a estrutura celular do vegetal resultando em maior perda de água, ganho de açúcar e, consequentemente, maior coeficiente de difusão do que os mamões frescos após a desidratação osmótica. A invertase extraída da polpa do mamão apresentou temperatura ótima de 45 °C e pH ótimo de 4.8. Considerando o baixo custo de produção do mamão e as características da invertase, essa fruta apresenta-se como potencial fonte de extração da enzima.
ABSTRACT
Fruits are generally recommended for a balanced meal, as they are good sources of vitamins, minerals, and fiber, which may improve blood glucose control. However, fruits have simple sugars with a wide glycemic index (GI) range. The purpose of this study was to analyze the sugar content and composition and to determine the glycemic indices of the most frequently consumed fruits in Korea, including apple, tangerine, pear, water melon, persimmon, grape, oriental melon, and peach. The sugar content and composition of the fruits were analyzed by high performance anion-exchange chromatography (Dinonex model DX-600). The GI of the fruits was measured in 13 healthy subjects (seven females and six males) after permission was received from the University Hospital institutional review board (KHU-IRB 1114-06). The subjects consumed 50 g of glucose as a reference and carbohydrate portions of eight fruits. Blood samples were collected at 0, 30, 60, 90, and 120 min after consuming the fruits. The GI values for the fruits were calculated by expressing the increase in the area under the blood glucose response curve for each subject. As a result, the total sugar contents of 100 g fruits were: grape (13.9 g), apple (12.3 g), persimmon (11.9 g), oriental melon (11.2 g), watermelon (9.3 g), tangerine (8.9 g), peach (8.6 g), and pear (8.3 g). The GI values of the fruits were as follows: GI value of peach (56.5 +/- 14.17), watermelon (53.5 +/- 18.07), oriental melon (51.2 +/- 18.14), tangerine (50.4 +/- 15.16), grape (48.1 +/- 14.05), persimmon (42.9 +/- 18.92), pear (35.7 +/- 14.38), and apple (33.5 +/- 11.92). These findings will help individuals choose fruit for controlling blood sugar.