摘要:

AbstractThe enthalpy of the order‐disorder transition of starch increased as the starch hydration period was increased from 1 h to 24 h. This was explained as the exothermic heat of hydration cancelling part of the endothermic heat of melting. Annealing of starch was shown to occur at 3 to 8°K below the Tm of starch. This would suggest that the Tg and Tm of starch does not occur at the same temperatu

ISSN:0038-9056    

DOI:10.1002/star.19860380902

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractEine kurze Darstellung der bisher in der Literatur beschriebenen Trennsysteme für die Analytik und molekulare Charakterisierung von Stärkepolysacchariden wird gegeben. Die von uns verwendeten bzw. weiterentwickelten Trennsysteme, die sich durch hohe mechanische Stabilität auszeichnen und auch im hochmolekularen Trennbereich reproduzierbare Ergebnisse liefern, werden vorgestellt. Für die Bestimmung der molekularen Verteilung mittels GPC muß eine Kalibrierung der Säulensysteme durchgeführt werden. Synthetische Amylosen und Dextrane, die sich jedoch strukturell unterscheiden, können zur Eichung herangezogen werden. Ihr unterschiedliches Trennverhalten und ihre Anwendbarkeit als Eichsubstanzen werden diskutiert. Es werden Zusammenhänge zwischen strukturellem Aufbau und molekularer Größe in Bezug zum Trennverhalten der Polysaccharide festgestellt. Statistische, rechnerische Verfahren erlauben sowohl eine Bestimmung der quantitativen Zusammensetzung der Stärken als auch die Bestimmung der mittleren Molekulargewichte (Zahlen und Gewichtsmittel) sowie der molekularen Uneinheitlichkeit von Stärkepolysacchariden. In Folge werden Anwendungsbeispiele aufgezeigt, die von der Grundlagenforschung (z. B. strukturelle Untersuchungen) über die Verwendung bei der Pflanzenzüchtung (Sortenwahl), bis hin zur Beurteilung von nativen und modifizierten Stärken im technologischen und pharmazeutischen

ISSN:0038-9056    

DOI:10.1002/star.19860380903

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractPhosphate diesters of waxy maize starch were prepared by crossbonding reactions using various concentrations of phosphorus oxychloride (POCl3) under conditions of controlled pH and temperature in order to have the modified starch with better functional properties. The waxy maize starch treated with 350 ppm POCl3(D. B.) showed higher paste viscosity and better heat resistance and acid proofing at a range of pH 3.0–4.0 than the unmodified starch and the other diesters prepared using 250–1,000 ppm POCl3. The viscosity at 25°C of 4% pastes, added salt, sugar and acid simulating a kind of brown sauce and cooked at 95°C for 10 min, containing the diester prepared by either 350 or 1,000 ppm POCl3, was higher and more stable in a refrigerator up to 4 months than that of the unmodified waxy maize starch. Application of the diester (1,000 ppm POCl3) to an effective thickener for “instant Miso soup” was also inv

ISSN:0038-9056    

DOI:10.1002/star.19860380904

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractStarch was chemically modified by substitution with hydroxyethyl groups to three levels (0.05, 0.1, 0.15 molar substitution) to reduce the brittleness of starch film for low humidity application. Substitution with hydroxyethyl groups reduced the density and sonic modulus and increased the moisture regain of the film. The brittleness of hydroxyethyl starch film at low humidity is reduced as the flexural rigidity, intermolecular friction, tensile modulus and breaking strength is decreased and breaking extension is increased.

ISSN:0038-9056    

DOI:10.1002/star.19860380905

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractEnzymatic saccharification of starch in the case of both pure starch and starchy raw materials is a long adopted technology successfully applied on industrial scale for many years. On the other hand, a feasible procedure for enzymatic saccharification of the other glucose polymer, cellulose, has been realized so far only on pilot‐plant scale. A particularly difficult problem is the enzymatic saccharification of cellulosic substances encrusted with lignin. The first step in starch and cellulose saccharification is pretreatment and digestion of the raw material. In the case of starch, this is solved by liquefaction in the presence of thermostable alpha‐amylase in a jet cooker. As a result, starch undergoes partial degradation and liquefaction. In the case of cellulose, the most economical method of pretreatment seems to be “steam‐explosion”, although this does not involve liquefaction either, i. e., saccharification proceeds still in heterogeneous phase. Comparison is made of the energy requirements of digestion of the raw materials and costs of enzymatic saccharification for both s

ISSN:0038-9056    

DOI:10.1002/star.19860380906

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractCotton plants were subjected to water stress ranging from –1.0 to –2.2 MPa. Starch content decreased during the initial decline in water potential from –1.1 to –1.4 MPa. This change was related to an increase in soluble α‐amylase activity and a decrease in bound glucan synthetase activity. Starch content then increased sharply to nearly 200% of control levels with a decrease in water potential to about –1.6 MPa. With a further reduction in leaf water potential to –2.2 MPa, both bound glucan synthetase activity and starch content decreased rapidly, while soluble α‐amylase activity continued to increase. The enzymic data demonstrate that effects of water stress on cotton are adverse, because starch degradation products are not translocated, but accumulate as reassembled starch in

ISSN:0038-9056    

DOI:10.1002/star.19860380907

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

摘要:

AbstractThe application of two innovative fixed film and suspended growth anaerobic biological systems to the treatment of grain and food processing wastewaters is discussed. A fluidized bed fixed film system and a suspended growth membrane system are described. The technical and economic factors dictating which system is selected for treatment of a specific industrial wastewater are discussed. Case history results from successful operation of full‐scale, demonstration, and pilot‐scale systems treating respectively, soy whey, cheese whey, and wheat flour processing wastewaters are presen

ISSN:0038-9056    

DOI:10.1002/star.19860380908

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19860380909

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19860380910

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY

ISSN:0038-9056    

DOI:10.1002/star.19860380911

出版商:WILEY‐VCH Verlag GmbH    

年代:1986

数据来源: WILEY