Study On Production Of Corn Fiber Oil, Oligosaccharides And Dietary Fiber From Destarch Corn Fiber

Corn fiber is a kind of cheap and abundant by-product of corn starch industryduring wet milling，which accounts for about10-20%of the dry weight of the corn.So the output is very large. But the use value of corn fiber is low at the present stagethat it is usually as animal feed.In this paper, the corn fiber was used as raw material.The study was to explore the higher economic value of corn fiber after afterremovaling of starch.The development levels of corn fiber oil, oligosaccharides anddietary fiber was explored respectively.The corn fiber contains19.41%of starch,18.52%of cellulose,37.47%ofhemicellulose,10.80%of protein,3.51%of fat and other ingredients. The more starchof corn fiber will directly affect the purification effect of downstream products, whichin turn affect the product value. Therefore the first step is to remove the remainingstarch effectively. In order to explore the best temperature, time and solid-water rateof the removal rate of starch from corn fiber, the cooking process was used on thebasis of single factor experiments and orthogonal experiment. The results showed thatoptimum destarching conditions were solid-water rate of1:17(g/mL), temperature of120℃, time of2h. Under these conditions, the removal rate of starch was89.09%.Corn fiber oil has more features than corn germ oil, such as more phytosterols andvitamin E.In this paper, the corn fiber oil was extracted by the solvent extractionmethod and the aqueous enzymatic method respectively.For the solvent extractionmethod,the results showed that optimum solvent was n-hexane, solid-liquid ratio was1:16(g/mL), time was1h, temperature was40℃. The extraction ratio of corn fiberoil was82.58%.For the aqueous enzymatic method, the results showed that thecellulase was4%，xylanase was5.33%，ratio of material liquid was1:12(g/mL)，timewas24h. The extraction ratio of corn fiber oil was75.05%. The contents ofphytosterols by two ways were higher than average, which are2870mg/100g and2960mg/100g respectively.In the aqueous enzymatic method，the precipitation by-product could be changedto dietary fiber after simple treatment. Its basic physical and chemical properties were detected. Results showed that water-hold power was5.85g/g, oil-hold power was2.98g/g, expansibility is2.50mL/g, adsorption capacity of bile acid sodium were20.15mg/g and40.63mg/g when the concentration were2mg/mL and3mg/mL.So thedietary fiber was basically same with the reported dietary fiber.At the same time in thepreparation of dietary fiber, the oligosaccharides mixture could be got after enzymesolution be dried.Corn fiber contains a high proportion of hemicellulose, it also has high nutritionalvalue. Hemicellulose could be extracted when corn fiber under the effect of diluteacid. The results showed that optimum extracted conditions were temperature of105℃, time of2h, acid concentration of1%,solid-water rate of1:12.5(g/mL).Underthese conditions，the almost all hemicellulose can be extracted.The oligosaccharideswere basic forms of hemicellulose after acid hydrolysis...