Abstract: Citrus peel can be divided into the white layer and the pigmented layer where contains different active ingredients respectively. To separate the white layer from the pigmented one can effectively improve the utilization of citrus peel. A citrus peel layered machine was designed in this paper. Peel of sweet orange was used as experimental material and the influence factors such as transfer rate of the citrus peel， depth of saw-tooth， rotation speed of the band-saw， and area of the citrus peel on the layered rate and homogeneity of the machine were investigated. The optimized manipulating processes of the machine were 40-60 tablets of peel per minute in transfer rate， 5 mm depth of saw-tooth， 1400 r·min-1 in the rotation speed of the band-saw and less than 5 cm2 in citrus peel area. Under the optimized condition， the layered homogeneity was 98%. Compared with the pectin and the carotenoids extracted from the whole citrus peel， the brightness in L* value of the pectin from the white layer increased by 53% and concentration of the carotenoids from the pigmented layer increased by 3.2 times with the same volume of solvent as that used in whole peel when 2 mm of pigmented layer was cut off using the peel layered machine.

Key words: citrus peel, layered machine, pectin, carotenoids