Study On Extraction And Separation And Molecular Distribution Of Hulless Barley Starch

Starch is a relatively cheap industrial raw material and one of the main components inpharmaceutical excipients. It is the main component of hulless barley，and it has uniquephysical and chemical properties and good potential for industrial applications. This topicfocus on the study of the extraction,physicochemical characteristics, separation, moleculardistribution of the hulless barley.The extraction of hulless barley starch: This experiment uses cellulose to assist starchextraction from hulless barley starch, choosing four main factors including added-amountof cellulose, enzymatic time, enzymatic temperature and pH value to design an orthogonaloptimization test based on single-factor tests. Using range analysis and variance analysis todeal with the test results, starch extraction yield as the evaluation index, this experimentidentifies the best extraction craft conditions. The result of the orthogonal optimization testshows that added-amount of cellulose, enzymatic temperature, as well as the interactionbetween enzymatic time and enzymatic temperature have significant effects on the starchextraction yield. The best extraction craft conditions encountered within the experimentrange would be: added-amount of cellulose is90U/g, enzymatic temperature is45℃,enzymatic time is8h and pH value is4.8, under which the starch extraction yield fromhighland barley is51.52%.We uses NaOH to assist starch extraction from hulless barley，choosing three mainfactors including the extraction time of NaOH, mass concentration of NaOH, Solid-liquidratio design an orthogonal optimization test based on single-factor tests. Using rangeanalysis and variance analysis to deal with the test results, starch extraction yield as theevaluation index, this experiment identifies the best extraction craft conditions. The resultof the orthogonal optimization test shows that the extraction time of NaOH, massconcentration of NaOH, Solid-liquid ratio have significant effects on the starch extractionyield. The best extraction craft conditions encountered within the experiment range wouldbe: the extraction time of NaOH was4hour, mass concentration of NaOH was0.5%,Solid-liquid ratio was1:5(g/mL),the starch extraction from hullessbarley was best. Underconditions above, the rate was49.43%.The physicochemical characteristics of hulless barley starch：This article adopts themethod of the gb for preliminary determination of the composition of highland barley hecontent of moisture content, crude fat, ash content, crude protein is9.84%,11.53%,0.67%and0.80%respectively. In this paper, the light transmittance of barley starch, solubility andswelling power, freeze-thaw stability and starch gelatinization characteristics were studied.The experiment results show that the light transmittance of the starch slurry decreased with the increase of the time; starch solubility and swelling force increases with the increase ofthe temperature; the freeze-thaw stability of starch paste by measuring its drainage rate toreaction analyze water rate is higher than its stability is poor; and by measuring its peakviscosity (2758cP), trough viscosity (1547cP), regenerative value (1035cP) to reflect thequality of its pasting properties.The separation of hulless barley starch：We use butanol precipitation separatingamylase and amylopectin from hulless barley starch. The results show that amylopectin isup to88%and amylose is very little,so the using of hulless barley starch shoud be focusedon the amylopectin. The main factors of the effect on separation and extraction are thestirring speed, the amount of the butanol and water, and the centrifugal forceThe molecular distribution of hulless barley starch: The hulless barley starch ismainly composed of amylopectin, and amylose is very little. By gel chromatographyanalysis, the range of peaks of amylopectin is55.0mL-67.2mL, the peak position is54mL,FWHM is7.0mL, the molecular weight is64.68×106g/mol.