摘要:

AbstractThe production of high purity starch from corn by the wet milling process requires the addition of considerable volumes of water, which subsequently must be removed by energy intensive processes including pressing, evaporation and drying. To reduce the process energy requirement, the water added for starch washing should be reduced, since this would result in a corresponding reduction in the steepwater to be evaporated. However, this also lowers starch quality. To overcome this problem, a tubular membrane reverse osmosis system was installed to produce a high purity process water from an intermediate stream (a starch‐protein suspension). This permeate replaces a large part of the fresh make‐up water added for starch washing. Each liter of water separated via reverse osmosis with a primary energy input of about 100 joule reduces the energy use of the triple effect steepwater evaporator by 1 300 jo

ISSN:0038-9056    

DOI:10.1002/star.19830350502

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractMaiskörner im unreifen Kolben enthalten zunächst nur einheitliche Stärkekörner wie das Hornendosperm des reifen Kornes. Unter dem Einfluß des sich entwickelnden Scutellums mit dem Embryo werden bei der Nachreife der Körner die Stärkekörner in der nächsten Umgebung dieser fermentativ abgebaut. Auf diese Weise entsteht im Inneren der Maiskörner das sogenannte Mehlendosperm als optisch inaktiver R

ISSN:0038-9056    

DOI:10.1002/star.19830350503

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractBuffalo gourd (Cucurbita foetidissimaHBK) starch was examined for possible food uses through physico‐chemical, rheologic, and organoleptic examination. The gelatinization and rheologic properties of this starch more closely resembled maize starch than those of other root and tuber starches. Detailed studies of pasting behavior revealed: a high initial pasting temperature, a stable gel viscosity throughout the temperature regime, increases in viscosity associated with increased starch concentration, an acid stability similar to that of maize, and substantial increases in final viscosity with the addition of other food ingredients (especially 25% sucrose). Gels subjected to freeze‐thaw conditions underwent a significant degree of retrogradation, suggesting the need for chemical modification prior to acceptable use of this starch in frozen products. Organoleptic evaluations of vanilla and chocolate puddings prepared with buffalo gourd starch indicated their potential consumer accepta

ISSN:0038-9056    

DOI:10.1002/star.19830350504

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractExtraction with 70% ethanol of chick pea, cow pea and horse gram yielded 7.1, 8.1 and 3.6%, respectively of free sugars, all showing the presence of galactose, glucose, sucrose, raffinose, stachyose and verbascose in varying proportions. Starch was isolated in 28 – 37% yields; whereas the unavailable carbohydrates were found to be 17.6, 14.5 and 24.2% respectively. All the fractions contained uronic acid, pentoses and hexoses in different proportions. No ethanol‐soluble sugar or starch was detectable in the husk. The husk was rich in cellulose which still contained small amounts of pentose constituents, indicating probably its incomplete extraction or a strong macromolecular associat

ISSN:0038-9056    

DOI:10.1002/star.19830350505

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractIn a previous contribution a hypothesis has been proposed to explain the substantial rise of the gelatinization temperature resulting from the addition of sodiumhydroxide to a salty starch suspension. Other phenomena arising from the interactions between starch and electrolytes as reversible swelling of starch, stable starch suspensions in concentrated solutions of electrolytes, influence of acids and changes in heats of adsorption and desorption can be explained by the same hypothesis. This contribution is devoted to explain these phenomena.

ISSN:0038-9056    

DOI:10.1002/star.19830350506

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractOne of the fundamental tasks of enzyme engineering is the production of biospecific enzymes. By determination of the thermodynamic parameters of ES complex formation the affinity chromatography binding of some vitally important enzymes of the starch industry has been increased nearly to the tenfold.A wide range of most various products for the starch industry can be obtained by enzyme engineering, through controlled product formation. Of the currently applied methods, chemical modification of the active centre seems to be the most practical solution. For this purpose, substrate‐binding functional groups catalyzing product formation have been determined by specific protein reagents, reaction kinetic methods, as well as by application of an immobilized substrateanalogue. By a kinetic method based on product distribution we performed the active centre mapping of the individual enzymes. From changes in the energy map due to modification of the functional groups the positions of the individual amino acid side chains in the active centre have been determined.With knowledge of these results the ratio for products formed in the case of individual amylolytic enzymes could be modified. This promising technique has been named by us „enzyme surgery”︁. With knowledge of the role and reactivity of the functional groups, controlled and planned enzymeimmobilization can be carr

ISSN:0038-9056    

DOI:10.1002/star.19830350507

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

摘要:

AbstractIn der vorliegenden Arbeit wurde die Benetzungswärme von Pektinen mit verschiedenem Veresterungsgrad durch Methanol unter Verwendung eines Mikrokalorimeters untersucht. Es wurde gezeigt, daß zwischen der Anzahl der methoxylierten Carboxylgruppen und der bei der Benetzung von Pektinen mit Methanol freigemachten Wärme eine strenge Proportionalität besteht. Die freigemachte Wärme liegt um eine Größenordnung höher als diejenige, die bei der Benetzung mit den übrigen aliphatischen Alkoholen erhalten wird. Der Exoeffekt ist auf physikalische Adsorption zurückzuführen; es wurde keine zusätzliche Veresterung beobachtet. Die spezifische Wechselwirkung zwischen Methanol und Pektinen erlaubt es, letztere als Adsorptionsmittel für Methanol aus wäßrigen Methanol/Ethanolmischunge

ISSN:0038-9056    

DOI:10.1002/star.19830350508

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19830350509

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19830350510

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19830350511

出版商:WILEY‐VCH Verlag GmbH    

年代:1983

数据来源: WILEY