摘要:

Examination of Freeze‐Dried Starch Pastes and Starch Sponges by Means of Scanning Electron Microscope.Pastes of potato and corn starch as well as various starch derivatives were examined by means of scanning electron microscope (SEM). As preparation method freeze fixation followed by freeze‐drying were used. Special attention was directed to changes occuring in pastes after slow freezing and defrosting.Sample preparation which is more complex for the SEM than for light microscope has the advantage of its picture giving more accurate information on paste structure than those obtained by light microscopy. On the one hand, tests confirm results obtained by other authors on the structure of starch pastes by means of light microscopic photography, furthermore, new information was gathered especially regarding non‐frozen pastes and pastes of starch derivatives.Illustrations of starch sponges as obtained by means of SEM are far more expressive than those obtained by conventional me

ISSN:0038-9056    

DOI:10.1002/star.19760280402

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

Molecular Weight Determinations of Carboxymethyl Starches.At the synthesis of carbomethylated starches of different degrees of substitution (DS) by monochloracetic acid on starch in alkali solution reacting in the presence of acetone for different periods of reaction time a partial decomposition of the macromolecules takes place. It could be stated that with increasing the substitution degrees the molecular weight of the ethers decreased relatively the most rapidly in the samples of lower substitution degrees. The mean valuesMnof the carboxymethylated ethers were determined by a chemical method of work which has been applied also for the determination of molecular weight of native starches. In order to determine the reducing capacities the factorfin dependence of the degree of substitution of the carboxymethyl starches has been calculated.

ISSN:0038-9056    

DOI:10.1002/star.19760280403

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

New Knowledge on Degradation of Starch by Hypochlorite. Part 2. Correlation between Aldehyde Content and Colour Formation during Drying of Oxidized Starches.By means of a standardized drying method yellowing of the hyplochlorite oxidized starch was proved to be directly dependent of the aldehyde content. Based on this method statements on storage life of oxidation products might be made.

ISSN:0038-9056    

DOI:10.1002/star.19760280404

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

Influence of Stirring and Dissolving Time on Accuracy of Starch Determination According to Ewers in Cereal and Milling By‐Products.From chemical analyses and their statistic evaluation it is seen that stirring during starch dissolving is indispensable for accuracy and good reproducibility of results during starch determination. Stirring of the sample according to the commonly applied technique can be recommanded as the most suitable method.Besides stirring it is most important to keep the exact time for starch dissolving. Even though with wheat fodder flour the highest starch content was found after dissolving time of 18 min, it is recommended not to exceed 15 min as the higher starch content is probably simulated by partly hydrolysis of pentosanes, hemicelluloses and also cellulose which become concentrated in the milling by‐produ

ISSN:0038-9056    

DOI:10.1002/star.19760280405

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

Influence of Sort and Locality on Viscosity Properties of Potato Starch.Regarding its rheological properties potato starch holds a special position compared with all other starches, which is mainly due to the phosphoric acid, resp. phosphate groups bound ester‐like to the amylopectin. The present work was carried out in order to find out, whether rheological properties of potato starch are also affected by outer influences such as year of cultivation, locality and sort. A marked influence of year of cultivation and locality as well as a less marked influence of the sort on phosphate and ash content of the starches became apparent. Locality exerts the strongest influence on viscosity. An influence of the sort can be stated, but it is mostly obliterated by superimpositio

ISSN:0038-9056    

DOI:10.1002/star.19760280406

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractA description is given of a process to recover potato protein from slightly diluted potato fruit juice. In this process the new technique of Ultra Filtration is applied. Some factors, which can give rise to serious operational problems, are mentioned. The process should help to ascertain the future of the potato starch industry, which is troubled now by severe government regulations on water pollution all over the world.

ISSN:0038-9056    

DOI:10.1002/star.19760280407

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

摘要:

AbstractThe paper presents data on the osmotic pressure of glucose syrup fractions obtained by reverse osmosis fractionation of a 43% D.E. commercial glucose syrup and membrane performance at different starting solids contents. Details regarding the production of glucose syrup fractions in the range 15–80% D.E. are given. The fractions produced consist of a narrower spectrum of sugars than is found in a commercial syrup of the same D.E. and thus offer new types of syrup to the industrial user of glucose syrups. Reverse osmosis and ultrafiltration seem to offer the only feasible economic means for obtaining specialised sugars from glucose syrup

ISSN:0038-9056    

DOI:10.1002/star.19760280408

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19760280409

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19760280410

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19760280413

出版商:WILEY‐VCH Verlag GmbH    

年代:1976

数据来源: WILEY