摘要:

AbstractLight‐scattering, viscosity and ultracentrifugal techniques have been applied to a number of amylopectin samples. These measurements have confirmed the very large size of the macromolecule, and shown that such values are real, and are not due to aggregation resulting from hydrogen‐bonding. The hydrodynamic behaviour of amylopectin has been compared with that of the closely‐related glycogen. The difference between the two has been shown to be due to the much more flexible, coil‐like nature of the amylopectin. An examination has been made of the factors governing the extension of amylopectin as the pH is varied, and it is shown that under appropriate solvent conditions a “coil‐to‐helix” transformation may be observed. The conformation of the amylopectin molecule is discussed, and the concept that the macromolecule is a two‐dimensional e

ISSN:0038-9056    

DOI:10.1002/star.19720240802

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractStructure and Properties of Grafted Potatoe Starch. I. Morphology and Solubility. Potatoe starch, which had been grafted with poly (acrylic compounds) by the Scott‐xanthation‐process was investigated. The graft layer on the surface and in the outer shell of the granule could be made visible by electron microscopy. Swelling of grafted granules was studied and the disolution process elucidated by different methods. As a result a model for a grafted starch‐granule is proposed, consisting of an ungrafted amylose core which is surrounded by a thick shell of amylo‐pectin‐graft

ISSN:0038-9056    

DOI:10.1002/star.19720240803

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractA sample of potato starch was cross‐linked with phosphorus oxychloride and its reaction with iodine compared with that of the parent starch using an amperometric titration method. Both starches had a similar iodine binding capacity but differed considerably in the rate of reaction with iodine. With the parent starch equilibrium was reached within a few seconds, whereas the cross‐linked starch required up to 30 minu

ISSN:0038-9056    

DOI:10.1002/star.19720240804

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractPaperchromatographic Separation as Identification Method of Native and Modified Wheat Starch. The previous experiences with paperchromatographic separation as identification method of native and modified starch samples has been useful in the study of wheat starch. This technique has been applied to the separation and identification of amylose and amylopectine of native and modified wheat starches (treated by phosphate, mineral acids and different temperatures). The results thus obtained were compared with the physico‐chemical characteristics of the same material. The modification procedure and the temperature influence are precisely outlined.The evaluation of the final data permits one to judge the applied technique favourably, the method can be considered as useful and complementary in the analysis of starch materia

ISSN:0038-9056    

DOI:10.1002/star.19720240805

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractProcessing Poperties of Local Maize. 1. Dry Milling. The latest statistical informations published by the German Government indicate that about 600.000 t corn were harvested in 1971. That means 51,1 dz per unit of cultivated area with an increase of 20% per year in the corn production.The total amount of corn is used for animal feeding in Germany. Some products derived from maize from types US‐Yellow and Plata are used for cereal breakfast, starch manufacture and in brewing‐industry in other european countries. There is little, if any, available information about physical qualities of corn varieties grown in Germany. Thus, it has been felt of great importance to fill this gap.This work was carried out on 15 varities grown at different localities. The samples were milled into grits, semolina, meal, flour and germs on a Standard‐Corn‐Laboratory‐Mill. The milling products were analysed for their fat content. In general the yield of semolina with a low fat content may be affected by the variety as well as by locality. Some of the German varieties showed higher fractions of low fat content than US

ISSN:0038-9056    

DOI:10.1002/star.19720240806

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractProcessing Properties of Local Maize. 2. Starch Production. Since the results of numerous preliminary tests have clearly demonstrated that compared with oversea maize samples also French yellow maize varieties under certain conditions and in parts even with same satisfactory results proved to be quite suitable as source material for starch manufacturing process, the general quality and analytical composition of all in all 30 different varieties of French yellow maize cultivated in the two Bavarian areas of Weihenstephan and Strassmoos and their extractable recoveries of starch, gluten, germs, fibre and steep‐water dry‐matter as well as their processing properties were determined. From these all in all 30 samples the results of analytical examinations and recovery determinations obtained from only eleven different varieties of French yellow maize cultivated in the Bavarian area of Weihenstephan were compared with the correspondent results obtained from another eleven samples of yellow maize from various French departments as well as from further eight overseas samples of yellow maize and white maize from Argentina, South Africa and U.S.A. and one additional sample of Roumanian yellow ma

ISSN:0038-9056    

DOI:10.1002/star.19720240807

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19720240808

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19720240809

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19720240810

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19720240813

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY