Research On Processing Whole-peeled Orange

In this paper, a study of making whole-peeled citrus, which is a relatively new product from citrus fruits, is done.In the course of experiment, some main parameters are selected out. The processing of whole-peeled citrus is made up of a series of steps, including water-infusion, enzyme hydrolysis of citrus albedo, vacuum package, microwave sterilization and storage in cool temperature. Results of the experiment are described in the following.(1) The epidermal peel of citrus fruit is removed by the way of water-infusion with a injector made by self. After done under such a pressure of 0.08-0. IMpa for about 2-3 minutes, the epidermal peel of fresh fruit could separate from the inner part. As a result, the fresh fruit can be peeled quite easily by hand, just for a few seconds. Compared with a traditional method through dealing with acid then base to peel, this means has a greater advantage and a higher efficiency . In this experiment, if the fresh fruit has been boiled for about 1 minute before the water-infusion, water can infuse into the asperge more easily.(2) The whole- peeled orange is plunged into a mixed enzymic solution, which is constituded with pectinase, cellulase and some amount of activator. Outcomings in experiment indicate that the proper concentration of pectinase in the mixed solution is 0.4g per 100ml, cellulase 0. 2g per 100ml, and the activator 0.5ml per 100ml. To peel 150~170g orange fruit, 200ml enzymic solution is necessary. And the conditions to deal with the peeled fruit are listed: pH4.0, 50癈. Under the over conditions, a smooth peeled fruit in fine appearance could be gotten after 40 minutes.(3) After peeled in enzymic solution, the gotten whole-peeled citrus fruit is packaged by a plastic bag, being thick of 0.075mm .The pressure in the bag is decreased to 0. 09Mpa by a vaccumor. Then the fruit is sterilized in a microwave stove, under the microwave at the power of 720w for 60 seconds. As a result, more than 99 percent of the bacterium have been killed, and the data is under the standard of GB. On the other hand, the result of E. coli CPU is negative. So the peeled fruit will be safe to take for human. As for the fruit, the shape is pretty and the taste is good.(4)After sterilized, the packaged whole-peeled fruit is stored under a cool temperature, being at 2-4C. Judging by the result of logCFU, at a standard of 5, the conclusion is that the shelf-life can be enlonged to over 38days, which is long relatively. As the nutrients concerned, the ascorbic acid would decreased during storing. About 20 percent of ascorbic acid has been destroyed after the product stored in the refrigerator for 15days. Nevetheless, the other nutrients hold contant during the course.The processed citrus fruit is delicious in flavor, pretty in appearance, nutrious in nutrition and convenient to eat. Go through the experiment, the fresh fruit has been processed as mininusly as possible, so the appearance, flavor and color are very similar to its original one. Based on this, the gotten products can be named as mininusly processed products.