摘要:

AbstractStarch was isolated from fresh mango seed kernels. The effect of glucoamylase‐α‐amylase on the granule ultrastructure was evaluated by scanning electron microscope. Amylose and amylopectin were isolated and their molecular structures were studied, using enzymic methods, HPTLC, and gel permeation chromatography. The structure of amylopectin was similar to amylopectin of other starches. The shortest branch chain had 6 glucose units. Amylose had a ß‐amylolysis limit of 77%. In order to improve solution stability during debranching with pullulanase and chromatography, amylose was partially acetylated. The debranchin of the unmodified and modified amyloses produced a 15–25% decline in the limiting viscositiy number and a slight shift in the molecular size distribution. These results are consistent with the concept that a fraction of the amylose molecules have limited branching and that these branched chains contain a significant number of gluc

ISSN:0038-9056    

DOI:10.1002/star.19810330702

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

摘要:

AbstractSome maize endosperm mutants have branched‐chain starch components with long exterior chains which make the blue‐value procedure for estimating amylose content questionable. Gel filtration was used to estimate starch composition of normal, high‐amylose, waxy and other maize endosperm mutants. Loosely‐branched polymers appeared responsible for the apparent amylose content. In some mutants high and intermediate loosely branched polysaccharides were found in addition to amylose. The sweet corn background of some endosperm genotypes influenced the types of polymers produced compared to the dent backgrounds used by previous rese

ISSN:0038-9056    

DOI:10.1002/star.19810330703

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

摘要:

AbstractThe gelatinization properties of potato starch were modified by coating the surface of the starch granules with lipids by an aqueous dispersion of monoglyceride or an ethanol monoglyceride solution. The volumes of gels were smaller than those of the untreated starch. In the polarizing microscope it was observed that decreased disruption of starch granules in connection with gelatinization occurs with increasing amount of lipids present on the surface. The gelatinization enthalpy and the gelatinization temperature at a low water content measured by DSC (Differential Scanning Calorimetry) were not influenced by the lipid coating. A third endothermic transition, however, was observed for the lipid‐coated starch. Freeze‐drying, used in the preparation of the lipid‐coated starch, was found to lower the gelatinization enthalpy as well as the gelatinization temper

ISSN:0038-9056    

DOI:10.1002/star.19810330704

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

摘要:

AbstractThe foodstuff from which the studied starches (maize, amylomaize, waxymaize, manioc, bread‐wheat, potato, rice and haricot bean) derive only has little influence upon the quantities of gamma radio‐induced acids. The ratiosrbetween the maximal and minimal found values are respectively 2.5 and 3.2 for formic acid and total acidity. Ifris equal to 13.6 for free acidity, it is only due to the very small values in haricot bean, potato and rice starc

ISSN:0038-9056    

DOI:10.1002/star.19810330705

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

摘要:

AbstractThe substitution parameters, molar substitution (MS) and degree of substitution (DS) for commercial O‐(2‐hydroxyethyl) derivatives (HES) of starch have been determined by measuring the relative amounts of glucose and its O‐(2‐hydroxyethyl) derivatives in hydrolysates of HES. The monomers in the hydrolysate were estimated by conversion to per‐O‐ethylated alditols which were analysed by gas chromatography. The identity of the monosubstituted derivatives was confirmed by their mass spectra and by synthesis of model compounds. Disubstituted monomers were identified by their mass spectra while trisubstituted components were no

ISSN:0038-9056    

DOI:10.1002/star.19810330706

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

摘要:

AbstractSeveral synthetic polymers were examined to isolate α‐cyclodextrin from an enzymatic hydrolyzate of starch. Amberlite XAD‐2 and XAD‐4 were suitable for this purpose. These polymers did not adsorb any type of sugars except cyclodextrins. The adsorbed cyclodextrin could be eluted by heating. By these procedures, α‐cyclodextrin from a crude cyclodextrin mixture was isolated and crystallized without using any organi

ISSN:0038-9056    

DOI:10.1002/star.19810330707

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19810330708

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19810330709

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19810330710

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19810330716

出版商:WILEY‐VCH Verlag GmbH    

年代:1981

数据来源: WILEY