Process parameter optimization of dual-roller peeling device for satsuma mandarin peeling machine

Abstract: Orange petal can is the traditional citrus processing product in China, and is also the most competitive product from China on the citrus processing product market in the international. The annual output of orange petal can in China is more than 0.6 million tons, accounting for more than 75% of the world canned orange production, and the annual export volume reaches 0.3 million tons, accounting for more than 70% of the world canned orange trade volume. China has replaced Japan and Spain and become the world center of the canned orange product; and Satsuma Mandarin is the main material of orange petal can. Currently, the peeling of citrus fruit mainly relies on the manpower, which not only has inefficient production, high labor intensity, but also is not conducive to product safety and healthy. With the rising of labor cost and the more and more strict hygiene requirement of the food market, replacing the manual operation mode and realizing the automatic peeling of citrus is the key problem to be solved for citrus processing industry. Huazhong Agricultural University has designed a kind of citrus stripping unit which includes ring cutting, pericarp opening, peeling and other processes, and the peeling process is realized by roller peeling device. In order to improve the peeling rate of citrus and decrease the damage rate of sarcocarp in the mechanical peeling process, this paper takes Satsuma Mandarin which is the main raw material of orange petal can as the test object, takes peeling rate, damage ratio and the sensory evaluation of citrus flavor as the main indexes, and conducts an experimental investigation of the process parameters and the effect of citrus peeling, so as to provide the basis for the design of Satsuma Mandarin peeling equipment. In the experiment, pretreatment method, roll rotation rate and plate translational speed are the main influence factors. And on the basis of the single factor test of the main affecting factors, an orthogonal test is conducted to study the influence of peeling effect for each factor on the roller peeling device using the self-designed peeling machine. Results show that the pretreatment method, roll rotation rate and plate translational speed have significant effect on peeling rate, while less effect on damage ratio. With the integrated balance method, the optimal parameters are selected, which are 3 min for hot steam heating, 60 r/min for roll rotation rate, and 12.98 mm/s for plate translational speed. Under the conditions, peeling rate is 100%, and damage ratio is 1.96%. The results provide the technical basis for the operation and optimization of the roll citrus peeling equipment.