RESUMO
4-Methylimidazole [4-MEI] is a simple nitrogen-containing heterocyclic compound, and recently classified as group 2B by International Agency for Research on Cancer [IARC]. Caramel coloring is widely applied food coloring in many food products including coffee, carbonated beverages, beer and wine. In present study, y-irradiation was applied to Caramel Color III to reduce the level of 4-MEI without color changes. Caramel coloring III was y-irradiated with 1, 3, 5, 10, 30, 50 and 100 kGy. Non-irradiated caramel coloring was served as a control. The level of 4-MEI and color were analyzed on all caramel coloring. The concentration of 4-MEI in the non-irradiated caramel coloring was 714.9 mg/kg. The level of 4-MEI in caramel coloring was significantly reduced from 3 kGy y-irradiated caramel coloring [p<0.05]. After 100 kGy irradiation, the amount of 4-MEI in caramel color was at 658 mg/kg, which equates 7.9% reduction from non-irradiated sample. No color change was observed on irradiated and non-irradiated caramel coloring [p>0.05]. Therefore, y-irradiation could be used as an alternative processing method to improve the quality of caramel coloring by reducing 4-MEI content without its color change
Assuntos
Corantes de Alimentos/efeitos da radiação , Carboidratos/efeitos da radiação , Raios gamaRESUMO
En este trabajo se analizaron los cambios en los parámetros de color (L, a, b, Æ, IB) de láminas de sardina durante la deshidratación osmótica a diferentes condiciones de concentración y temperatura de la solución osmótica. Las sardinas (Sardinella aurita) se cortaron en láminas (20,1×15,0×6,4 mm3), se les midió el color y se formaron 175 grupos experimentales de 4 láminas cada uno. Se introdujeron simultáneamente siete grupos en una solución osmótica de concentración y temperatura dadas para someterlos a deshidratación osmótica, posteriormente se removió un grupo a los 20; 40; 60; 90; 120; 180 y 240 min de transcurrido el proceso osmótico y se midió el color en las láminas. Este procedimiento se efectuó para cada condición de acuerdo a un diseño factorial 5x5 donde la temperatura y concentración eran 30; 32; 34; 36 y 38°C, 0,15; 0,18; 0,21; 0,24 y 0,27 g NaCl/g, respectivamente. Se obtuvieron valores iniciales de L (36,48 ± 0,77), a (6,47 ± 0,64), b (8,74 ± 0,49), Æ (0) y IB (37,42 ± 0,69). Los valores finales variaron para L entre 40 y 47, a entre 4,2 y 2,6, b entre 7,5 y 5,7, IB entre 39,5 y 45,0 y Æ entre 5,3 y 10,4 dependiendo de las condiciones de deshidratación. Los valores de a y b disminuyeron (P<0,05) al incrementar el tiempo de deshidratación y la concentración, mientras que los de L, Æ y IB aumentaron (P < 0,05). Las disminuciones en a y b fueron menores al incrementarse la temperatura mientras que los aumentos en L, Æ y IB fueron mayores. Se obtuvieron modelos de predicción de los cambios en el color en función de las condiciones de la deshidratación osmótica.
The changes on the color parameters (L, a, b, Æ, whiteness index) of sardine sheets during osmotic dehydration were analyzed at different temperatures and brine concentrations. Sardines (Sardinella aurita) were cut into sheets (20.1x15.0x6.4 mm3), color was measured and 175 groups with 4 sheets in each were formed. Seven groups were introduced simultaneously in an osmotic solution of a desired concentration and temperature for carry out osmotic dehydration, one group was removed at 20; 40; 60; 90; 120; 180 and 240 min, and color of sheets was determined. This procedure was performed for each test condition according to a 5x5 factorial design where the temperature and concentration were 30; 32; 34; 36 and 38°C, 0.15, 0.18, 0.21, 0.24, and 0.27 g NaCl/g brine, respectively. Initial values for L (36.48 ± 0.77), a (6.47 ± 0.64), b (8.74 ± 0.49), Æ (0) and WI (37.42 ± 0.69) were obtained. Final values ranged for L from 40 to 47, for a from 4.2 to 2.6, for b from 7.5 to 5.7, for WI from 39.5 to 45.0 and for Æ from 5.3 to 10.4 according to dehydration conditions. Values for a and b decreased (P<0.05) with increasing both dehydration time and temperature while those for L, Æ and WI index increased (P < 0.05). The decreases in a and b values were lesser with increasing temperature while increases in L, Æ and WI values were higher. Models for prediction of color changes as functions of the conditions of osmotic dehydration were obtained.