Studies On Carrot Residue By Extrusion Spray Processing And The Properties Of Treated Carrot Residue

In the study the extruding technic had been used to increase the content of soluble dietary fiber. Based on the single factor experiments, the orthogonal experiment was used to confirm the optimization of extrusion conditions, and compared the carrots residue’s chemical and physical properties before and after extrusion. New ideas and theoretical guidance were provided for new functional food research and industrialization, respectively.The result which the optimum condition of extrusion spray technic to improve the soluble dietary fiber (SDF) in carrot residue was as follows:die hole diameter 4 mm, temperature 177℃, screw speed 180 r/min. Made the SDF content increased to 25.3% from 16.8% in raw materials, and other basic nutrients contents didn’t change.A novel blasting extrusion processing was used to carrot residue, and had a certain degree effect of water holding capacity, swelling capacity, water-soluble capacity and the oil holding capacity, respectively increased by 11%,61%,1.3%,34%. And DSC measurement results show that under 200℃, carrot residue has strong thermal stability. Microstructure observation (SEM) results showed that the carrot residue after extrusion spray treatment had more holes, more porous and unconsolidated fragments.In addition, a novel water-soluble polysaccharide was isolated and extruded from carrot residue SDF and its superficial structure analysis was concisely elaborated. Carrot residue SDF was extracted by alcohol sedimentation method. The results showed that CRSDF was a kind of neutral sugar and soluble in water but insoluble in organic solvents, which contain little starch and proteins, contain 6.6% reducing sugar.The aim of this study was to elucidate the effects of water-soluble dietary fibers from carrot residue could detoxify harmful metabolites in hunman body. Water-soluble dietary fibers from carrot residue were used to evaluate their physicochemical properties and binding capacities for Pb ion, bile acid in vitro. The water-soluble dietary fibers (SDF) showed a high cation-exchange capacity and a high adsorption capacity for Pb cation. The water holding capacity of SDF was 6.63 ± 0.19g/g, peanut oil binding capacity was 6.41 ± 0.12 g/g and lard binding capacity was 8.73± 0.28 g/g. The maximum binding amount of sodium deoxycholate can be achieved 64.8% and SDF could binding with sodium cholate, sodium deoxycholate and sodium taurocholate, respectively. The rate of SDF adsorption sodium deoxycholate and sodium cholate was faster than sodium taurocholate.Neutral polysaccharide was purified from carrot residue SDF by DEAE-52-cellulose column chromatography systems. A single symmetrical narrow peak was eluted high performance liquid chromatography (HPLC), and the average molecular weight (Mn) was estimated to be 59846 Da. Neutral polysaccharide was composed of arabinose, xylose, glucose, and galactose. Molar ratio was 0.58:1.50:1.0:2.02. The FTIR spectra shows that CRSDF has stretching of -OH groups and C-H stretching. The peak position did not change before and after the extrusion, proved the stability of the extrusion process.