Efeito de diferentes processamentos sobre o teor de ácido ascórbico em suco de laranja utilizado na elaboração de bolo, pudim e geléia

Abstract

RESUMOEste estudo teve por objetivo avaliar a estabilidade do ácido ascórbico em suco de laranja cv. "Pêra" utilizado como ingrediente na elaboração de bolos, pudins e geléia. Os bolos e os pudins foram assados em forno convencional e de microondas, e a geléia foi elaborada em tacho aberto. Estas preparações foram submetidas a análises para determinação dos teores de ácido ascórbico e de sólidos solúveis totais, da acidez total titulável e do pH. Os teores de ácido ascórbico em bolos e pudins, quando comparados ao do suco de laranja in natura apresentaram redução de, respectivamente, 76,09% e 41,76%, quando assados em forno de microondas, e de 84,21% e 46,71%, quando assados em forno convencional. A geléia de laranja apresentou redução de 24,86% no teor de ácido ascórbico em relação ao suco de laranja in natura. A cocção de bolos e pudins realizada em forno de microondas proporcionou maior retenção do ácido ascórbico, quando comparada àquela realizada em forno convencional. Estas preparações apresentaram perda superior à da geléia, elaborada em tacho aberto. Foi observado, também, que os bolos perderam mais ácido ascórbico do que os pudins, em ambos os métodos de cocção avaliados. Palavras-chave: ácido ascórbico, suco de laranja, processamento térmico. SUMMARY EFFECT OF DIFFERENT PROCESSING METHODS ON ASCORBIC ACID CONTENT IN ORANGE JUICE USED TO MAKE CAKES, PUDDINGS AND JELLY. The aim of thisstudy is to analyze the stability of ascorbic acid in orange juice cv. "Pera" used as an ingredient to prepare cakes, puddings and jelly. Cakes and puddings were baked in conventional and microwave ovens and the jelly was prepared in a pan without a lid. Ascorbic acid content, total soluble solids, total tritatable acidity and the pH were determined in all prepared foods. The AA content in cakes and puddings, when compared to the content of orange juice in natura had a reduction of 76.09% and 41.76%, respectively when baked in a microwave oven and of 84.21% and 46.71%, when baked in a conventional oven. Orange jelly showed a reduction of 24.76% in the ascorbic acid content related to orange juice in natura. Preparing cakes and puddings in a microwave oven provided a greater retention of the ascorbic acid, when compared to the conventional oven. These preparations had a higher loss to jelly, made in a pan without a lid. It was also observed that the cakes lost more ascorbic acid than the puddings in both evaluated cooking methods.

Bioactive Compounds and Antioxidant Activity of Pineapple Fruit of Different Cultivars

“…In this study, Imperial cultivar showed promising results, since its vitamin C content was similar to that found for orange, citrus fruit considered as a reference for vitamin C content (SILVA et al, 2006;. PADAYATTY et al, 2003).…”

Nutritional and antioxidant potential of canjiqueira fruits affected by maturity stage and thermal processing

“…Both unripe and ripe fruit jellies showed higher IC 50 value, which is related to lower antioxidant activity. The reduce in AA content resulting from jelly processing was previously reported by SILVA et al (2006) in jelly made of orange juice, with 75% of retention in ascorbic acid content. Thermal processing can reduce the levels of phytochemicals due to lost of cellular integrity by enzymatic action or by factors such as light and oxygen (VOLDEN et al, 2008).…”

“…Processing cause nutritional changes in foods, but it also makes them more sensorially appealing to the consumers and increases their shelf life (SILVA et al, 2006). Processing can affect the levels of some bioactive compounds of fruits and vegetables due to the exposure to oxygen and long periods of high temperature (RODRIGUEZ-AMAYA, 1999).…”

Persimmon pulp and jelly: chemical characterization and rheological behavior

“…The persimmon jellies presented values of solids superior to 65 o Brix, in line with this recommendation. SILVA, LOPES and VALENTE-MESQUITA (2006) in the elaboration of orange jelly, found value of 65 ºBrix, value identical to that found by DAMIANI et al (2008), who elaborated a jelly from mango peels. FOLEGATTI et al (2003) still in the study of industrial use of umbu, processed the jelly at the proportions of 40:60 and 50:50 and obtained values of 67.5 ºBrix and 67.1 ºBrix, respectively.…”