摘要:

AbstractIn dem vorliegenden Beitrag werden von insgesamt 15 verschiedenen Verfahren der industriellen Weizenstärkegewinnung sechs Produktionsprozesse beschrieben. Die Einteilung der 15 Verfahren kann einmal nach den beiden möglichen Ausgangsmaterialien Weizenkorn und Weizenmehl und zum anderen nach der Trenntechnik in mechanische, chemische und fermentative Separation erfolgen. Schließlich ist auch eine Einteilung in bezug auf das Nebenprodukt Weizenkleber dahingehend möglich, daß in Abhängigkeit von der angewandten Verfahrenstechnik Vital‐Kleber oder denaturierter Kleber erhalten wird. In dem vorliegenden Fall ist die Klassifizierung der Produktionsprozesse nach den beiden möglichen Ausgangsmaterialien Weizenkorn und Weizenmehl vorgenommen worden. Von den insgesamt 15 Produktionsprozessen gehen sechs Verfahren von dem Rohstoff Weizenkorn ausAbschließend wird ein modifiziertesLongford‐Slotter‐Verfahren vorgestellt, nach dem im Laboratorium unvermahlener Weizen unter Zusatz von 0,2% Schwefeldioxid bei einer Temperatur von 37°C 15 h gequollen wird. Nach diesem modifizierten Longford‐Slotter‐Verfahren ist es bei einmaliger diskontinuierlicher Zentrifugation und einmaliger Flutung möglich gewesen, 54% Stärke mit einem Rohproteingehalt von 0,4% zu gewinnen, was einem Wirkungsgrad von

ISSN:0038-9056    

DOI:10.1002/star.19840360102

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractThe properties of starches during development of several endosperm mutants of maize were investigated. Starch contents of normal andwaxy(wx) kernels were higher than those ofdull (du), sugary‐2 (su2), and amylose‐extender (ae) kernels, and in general the greater increase in starch contents occurred earlier in kernel development. The normal,du, su2, andaemutants in that order, respectively, increased the apparent amylose concentration of the starches as measured by the “blue value” method. Within each of these genotypes, absorption intensity increased and λ max. of absorption curves shifted to a longer wavelength region with increasing maturity. Waxy starches did not change in either of these properties at any of the developmental stages. Few detectable differences were observed in X‐ray diffraction intensity, gelatinization temperature, heat of gelatinization, and the photopastegrams within these genotypes during development. Exhaustive degradation of starch granules by glucoamylase showed thataestarches were more resistant to amylase than the other starches. Except forwx, the starches tended to be more resistant to amylase with increasin

ISSN:0038-9056    

DOI:10.1002/star.19840360103

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractThe availability for reaction of amylose and amylopectin in potato starch was investigated by etherifying potato starch in granular form and in solution with diethylaminoethylchloride to a very low degree of substitution. The distribution of ether groups over both starch fractions was subsequently determined. A higher reactivity of amylose with respect to amylopectin was found for granular starch, in contrast with reaction in solution, where both starch fractions show almost equal degree of substitution. This indicates a difference in physical state between amylose and amylopectin in granular potato starch. Furthermore it was shown, that the relative reactivity of the starch fractions can be varied by physical modification of the native starch.

ISSN:0038-9056    

DOI:10.1002/star.19840360104

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractThe effects of organic molecules on the gelatinization temperature of starch in water seem to stem from the electron polarizability of those organic molecules. The same fundamental characteristic is the basis of the explanation for the effects of anions on the gelatinization temperature. The proposed hypothesis is capable to explain the familiar phenomena which arise from the interactions between starch and electrolytes.

ISSN:0038-9056    

DOI:10.1002/star.19840360105

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractThe corn hull hemicellulose was isolated from unsteeped and for 30 and 60 h steeped grains. The hemicellulose was fractionated by Sephadex G‐100 column chromatography in order to compare the fraction constituents of each hemicellulose. Also the relative percentage and molar ratio of the sugars in each fraction were determine

ISSN:0038-9056    

DOI:10.1002/star.19840360106

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

摘要:

AbstractFollowing the introduction and widespread application of immobilized glucose isomerase for the industrial production of isosyrup (HFCS), the most significant challenge facing experts is to solve the problem of increasing the fructose content. In addition to well‐known procedures another approach may be the changing of the equilibrium of the enzymatic reaction by modifying the active centre of the enzyme. Histidyl‐, ϵ‐amino‐, arginyl‐, tyrosyl‐ and tryptophyl‐ amino acid side chains in the active centre have been modified by means of selective protein reagents. The results were evaluated by kinetic methods and the role of functional groups of amino side chains has been determined. A new hypothesis is proposed for the mechanism of enzym

ISSN:0038-9056    

DOI:10.1002/star.19840360107

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19840360108

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19840360109

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19840360110

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19840360114

出版商:WILEY‐VCH Verlag GmbH    

年代:1984

数据来源: WILEY