عنوان مقاله English
The goal of this research is to compare the traditional and industrial methods in production of sour orange juice and to reach the optimum conditions for juice color maintenance. In the present study the juice was collected from three stages of sour orange juice production line namely prior to pasteurization process (UNP), following pasteurization and homogenization (PH) and after supplementing the juice with standard quantity of sodium metabisulfit (PHS). The juice from all three stages was poured into dark color air tight seal glass bottles. The samples were stored under ambient temperature (~ 20oC and 35oC), cold room temperature (~ 4oC) and freezing (-18oC). Various physicochemical characteristics including pH, total solid content (Bx), HMF and vitamin C contents and color parameters were assessed at one week intervals for 16 weeks. Results were analyzed with SPSS software in 95% confidence level. The analysis of the data indicates that the color quality decreased with time while HMF content shows an increasing trend. The vitamin C shows a decreasing trend with time and increasing temperature. The trend of color change in samples stored in refrigerated and freezing conditions were almost the same. Furthermore, sodium metabisulfit shows its color protecting effect only at higher storage temperatures (25 and 35oC) and during final weeks of storage. In the present study the changes on pH and total solid content of the samples regardless of storage temperature and condition was negligible.
کلیدواژهها English
