摘要:

Wide‐Line NMR of Water in Starch Gels at 295 KThe purpose of this work was to decide if it is possible to detect bound and free water in starch gels for T>0°C by wide‐line NMR at various RF‐levels. Therefore, we measured the longitudinal (T1) and transverse (T2) relaxation of the water protons in maize starch gels of different water concentrations at 295 K by pulsed and wide‐line NMR.The absorbed water showed single‐phase behaviour at all water concentrations. A separation into bound and free water was not seen. The determination of bound water by wide‐line NMR is shown to be a pure effect of RF‐saturation which can be calculated by the T1and T2valu

ISSN:0038-9056    

DOI:10.1002/star.19730250902

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractThe submicroscopic radial structure of the starch granule can be explained by folded‐chain crystals better than by microfibrils. Such microfibrils described especially by Sterling and also observed by myself may be artefacts which are caused by steps of carbon coated fracture planes of starch granules.The partly submicroscopic tangential shell structure of the starch granule is probably caused by a periodical change of higher and lower molecular fractions both of amylose and amylopectin.This conclusion follows from staining and fluorochroming as well as from phosphoric tungstic acid contrasting experiments in light and electron microscopy. The more crystalline layers consist exceedingly of high molecular fractions. The less tight and more amorphous regions of layers which are easier oxydated (e. g. by periodic acid) and hydrolysed (by a‐amylase) are composed of lower molecular fractions rich in phosphorus and nitrogen containing compounds (especially in wheat starch) and therefore are more hydrophilic and abounding in wa

ISSN:0038-9056    

DOI:10.1002/star.19730250903

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractThe starch granule size and distribution has been determined on 29 different samples of barley. There is a wide range in the ratio of small to large granules which varies from a minimum of 5.5:1 to a maximum of 37:1. Small granules were separated from large granules in four varieties and the average weight of the granules determined. From these values the actual percentage of small granules in the original barley starch was determined. Small granule starch may account for from 6.2–30.6% of total starch weight in the varieties examine

ISSN:0038-9056    

DOI:10.1002/star.19730250904

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractStarch granules of less than 10 μm in diameter have been separated from a sample of Cappelle Desprez wheat by a micro‐sieving technique. These smaller granules were found to contribute some 30% of the total weight of the star

ISSN:0038-9056    

DOI:10.1002/star.19730250905

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractA bacterial amylase which is active and stable in starch solutions at temperatures above 100°C has been developed. New liquefaction methods are envisaged because the enzyme is active over broader temperature‐ and pH‐ranges and is less dependent on Ca‐ions.Pilot plant experiments have been carried out, liquefying wheat and maize starch using reaction times of approx. 2 h at 105°C. The 12–14 DE‐solution could be cooled to 60°C and saccharified without retrogradation. A high temperature treatment was not considered necessary.In the traditional enzymatic liquefaction procedures the cooling stage to 85°C after high temperature treatment of starch has been very critical. The new enzyme may be added at approx. 100°C, and the risk of retrogradation is therefore g

ISSN:0038-9056    

DOI:10.1002/star.19730250906

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

摘要:

AbstractA method for the determination of silica in corn syrup is presented. A silico‐molybdate complex is formed. The interfering phospho‐molybdate is neutralized by the addition of oxalic acid. The silico‐molybdate complex is reduced by 1‐amino‐2‐naphthol‐4‐sulfonic acid to give the heteropoly blue which absorbs at 810 nm. Repeated analysis of a corn syrup gave a value of 17.8 microgram silica per gram of solids and a standard deviation of 0.06 for nine determinations. The recovery of added silica was in the r

ISSN:0038-9056    

DOI:10.1002/star.19730250907

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19730250908

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19730250909

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19730250910

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19730250911

出版商:WILEY‐VCH Verlag GmbH    

年代:1973

数据来源: WILEY