ISSN:0038-9056    

DOI:10.1002/star.19820340802

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractType A starches (Manihot utilissima, Dioscorea dumetorumandColocasia antiquorum) and type B starches (Canna edulis, Dioscorea alataandDioscorea cayenensis) are investigated. Results show that the degradation of the pure tuber starch as compared with that of feeds made from a particular starch is more or less the same. However, type A starches are more rapidly degraded by bacterial α‐amylase. The susceptibility to attack is compared to the nutritional efficiency of the feeds using axenic and holoxenic chickens. Comparison of the degree of degradation of the starch granules in the crop as well as in the feces (byin vitroandin vivostudies) is made by scanning electron microscopy. Type A starches show always a higher susceptibility to α‐amylase attack. The feed efficiency tested on chicken and digestibility of tuber starches in the sheep rumen and in the chicken crop increase as their ease of degradation by bacterial α‐amylase (in vitro) i

ISSN:0038-9056    

DOI:10.1002/star.19820340803

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractThe gelatinization behaviour of 6 starches extracted from corn flours and grits has been studied in relation to their performance in extrusion. It was found that favourable extrusion behaviour correlated with a high amylose content, a significantly lower gelatinization temperature and a more rapid gelatinization process as monitored by small angle light scattering in response to temperature jumps.

ISSN:0038-9056    

DOI:10.1002/star.19820340804

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractThe rheological properties of concentrated wheat starch gels were measured with shear stress relaxation experiments in cone‐plate geometry. The water content of the investigated gels were 80, 60, 50 and 30% (w/w), respectively, and the relaxation modulus (G) and half relaxation time (T1/2) were studied after heating to different temperatures. For the gels with 50% and 60% (w/w) of water, a maximum value ofGwas obtained when the temperature interval for gelatinization was passed. When these gels were heated to higher temperatures,Gdecreased, andT1/2 increased, whereas gels with 30 and 80% (w/w) of water behaved differently. The influence of particle size distribution on the rheological properties of concentrated starch gels, was also investigated. It was found thatGandT1/2 increased with a greater fraction of small starch granule

ISSN:0038-9056    

DOI:10.1002/star.19820340805

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractAn einigen mittel‐ und hochveresterten Citratstärken (2,6 bis 3,75% esterartig gebundene Citronensäure) wurde das Ausmaß der Esterspaltung unter milden Reaktionsbedingungen (pH = 2,5 bzw. 4,4,8,0 und 8,5; Temperatur 40 bzw. 55 und 80 °C) untersucht. Im sauren Bereich werden in 100 h maximal 5% der esterartigen Bindungen gespalten. Im schwach alkalischen Bereich werden bei 40 °C ähnliche Werte gefunden, bei 80 °C und pH = 8.0 wurde jedoch innerhalb von 20 h der Citratester zu 80%

ISSN:0038-9056    

DOI:10.1002/star.19820340806

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractThe exocellular α‐amylase of a strain ofAspergillus nigervan Tieghem (elaborating both dextrifying and saccharifying thermophilic amylases) was purified to homogeneity. Purification was achieved by providing cultural conditions for the organism to preferentially synthesize α‐amylase and fractionation of the culture filtrate by DEAE‐Sephadex chromatography. Its purity was established by gel electrophoresis and confirmed by sedimentation studies. The molecular weight of the enzyme was 56,230. Its Km values on different starches, temperature and pH optima for activity and energy of activation were established. Compared to literature values for other fungal α‐amylases, this enzyme exhibited a lower energy of activation, increased tolerance to lower pH and enhanced affinity to starch, highlighting its potential industrial application. While Ag+, Pb2+, Hg+, Al3+and EDTA inhibited the activity of the enzyme, Ca2+enhanced its activity, apart from conferring thermal stability and lowered activation energy. The product of its action on starch were maltooligosaccharides, maltose a

ISSN:0038-9056    

DOI:10.1002/star.19820340807

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

摘要:

AbstractThe physiological response to the ingestion of glucose and glucose syrups is well documented in the literature. More recently, hydrogenated glucose syrups have become available but little is known of their physiological effect in man although sorbitol (hydrogenated glucose) has been used for many years in diabetic foods. Some metabolic effects of maltitol (hydrogenated maltose), which is a major component in hydrogenated syrups, have been described but the results obtained are equivocal. Our present work concerns physiological studies of hydrogenated glucose syrups and maltitol in animals and human subjects. In rats it has been shown that maltitol is utilized in some quantity by the gut microflora as shown by differences between conventional and germ‐free animals. Intravenously injected maltitol is excreted almost quantitatively in the urine producing no significant rise in blood glucose. This contrasts sharply with intravenously injected maltose which induces a significant blood glucose rise and of which less than 10% is excreted in the urine. In human subjects hydrogenated glucose syrup may be tolerated at levels between 80 and 120g per day without diarrhoea. Our studies indicate that although after an oral dose maltitol and hydrogenated glucose syrup induce lowered blood glucose and serum insulin peak values, compared with glucose, total influx of the three carbohydrates shows no difference. This may have importance regarding the use of maltitol and hydrogenated glucose syrup in diabetic foods. Long term feeding trials with human subjects, using maltitol and hydrogenated glucose syrup as the sole dietary carbohydrates, show that some adaption to the carbohydrates occurs during the trial as judged by elevated blood glucose and serum insulin peak values at the end of the trial compared with initial value

ISSN:0038-9056    

DOI:10.1002/star.19820340808

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19820340809

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19820340810

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19820340811

出版商:WILEY‐VCH Verlag GmbH    

年代:1982

数据来源: WILEY