摘要:

AbstractAcid Hydrolysis of β‐D‐Fructofuranosyl Bonds. Generally, glycofuranosides are hydrolyzed at a higher rate than the glycopyranosides under identical conditions. The present paper is dedicated to the hydrolysis of β‐D‐fructofuranosides which are containing different aglycone moieties: methyl group, substituted methyl group (in inulin), glucosyl group (in sucrose) and substituted glucosyl group (in raffinose). The energies of activation were between 25.1 and 25.6 kcal/mole and the entropies of activation between 8 and 9.5 entropy units. The values of the reduced rate constants (values extrapolated to pH 0 and 100°C) depend on the size of the aglycone.The mechanism of splitting of ketofuranosides differs from that of the aldofuranosides and of aldopyranosides. According to the reported data these compounds are hydrolyzed by formation of a tertiary carbeniumcation, i. e. by plitting of the O‐fu

ISSN:0038-9056    

DOI:10.1002/star.19720241002

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractCalorimetric studies have been made on the complex formation of cyclodextrins with triiodide ion or p‐nitrophenolate anion in aqueous solutions by using microcalorimeter. The heats of complex formation of α‐, β‐, and γ‐dextrin, respectively with both the guest compounds were obtained and marked differences in magnitude of the reaction heats were observed for the three dextrins. The association process of the dextrins with the guest compounds in aqueous solutions was briefly discussed with respect to the points of stoichiometry and ther

ISSN:0038-9056    

DOI:10.1002/star.19720241003

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractBarley starch exists in two clearly defined populations of large (ca. 25 μ diameter) and small (ca. 5, μ diameter) granules, whilst in wheat there is a range of granule sizes with no similar bimodal distribution. The small granules of barley represent about 90% of the total starch granules by number, but account for only about 10% of the total starch in weight. Fractions containing only large or only small granules have been isolated from both barley and wheat. The small granules from barley have a higher amylose content than the large granules, a higher gelatinisation temperature, and are usually associated with more protein. In contrast, large and small granules from wheat differ only slightly in their respective amylose contents but, like barley differ in gelatinisation temperatures and amounts of associated protein. It is proposed that starch synthesis in the small starch granules of barley is under different genetic control from that in the large granule

ISSN:0038-9056    

DOI:10.1002/star.19720241004

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractThe investigation has shown damaged starch to be a significant factor in the high water absorption by 63 straight‐run flours of a number of varieties of Indian wheats. A significantly high positive correlation (r = + 0.81 to + 0.87) was obtained between water absorption and damaged starch contents compared to a value of + 0.50 for water absorption and protein content. The prediction of water absorption from damaged starch and protein contents is discusse

ISSN:0038-9056    

DOI:10.1002/star.19720241005

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractAbsorption of SO2During Swelling of Maize. Part 1. Distribution in Fractions. It has been shown by means of S‐35‐labelled SO2, that protein and germ take up most of SO2during the swelling of corn. The uptake by the maize kernels is only 6% from the amount solved in swelling water. The swelling process does not change the fatty acids composition of the total lipids of corn. There are only traces of sulfur in the extracted f

ISSN:0038-9056    

DOI:10.1002/star.19720241006

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

摘要:

AbstractAbsorption of SO2During Swelling of Maize. Part 2. Technological Aspects. Investigations had been made by means of a modified method for practical starch extraction from maize kernels. Already after steeping in 0.8% sulfur dioxide in steeping water a final sulfur dioxide content in the starch lower than 8 mg/kg was observed. Studies in three german starch plants showed that the sulfur dioxide content of products from different process steps before the hydrocyclon station varied. After refining of raw milk this differences could not be observed any longer. Due to a further addition of sulfur dioxide during the refining steps the industrially produced starches contained much more sulfur dioxide than those extracted by the laboratory method. These results have been confirmed by processing industrially steeped maize in the laboratory without further addition of sulfur dioxide during the refining steps.

ISSN:0038-9056    

DOI:10.1002/star.19720241007

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19720241008

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19720241009

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19720241010

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19720241013

出版商:WILEY‐VCH Verlag GmbH    

年代:1972

数据来源: WILEY