عنوان
پدید آورنده
موضوع
رده
کتابخانه
محل استقرار
شماره کتابشناسی ملی
شماره
TLpq303877270
زبان اثر
زبان متن نوشتاري يا گفتاري و مانند آن
انگلیسی
عنوان و نام پديدآور
عنوان اصلي
Preparation and properties of a thick -boiling, phosphorylated wheat starch for food use, and location of phosphate esters on starch by phosphorus-31-NMR spectroscopy
نام عام مواد
[Thesis]
نام نخستين پديدآور
S. T. Lim
نام ساير پديدآوران
P. A. Seib
وضعیت نشر و پخش و غیره
نام ناشر، پخش کننده و غيره
Kansas State University
تاریخ نشرو بخش و غیره
1990
مشخصات ظاهری
نام خاص و کميت اثر
148
یادداشتهای مربوط به پایان نامه ها
جزئيات پايان نامه و نوع درجه آن
Ph.D.
کسي که مدرک را اعطا کرده
Kansas State University
امتياز متن
1990
یادداشتهای مربوط به خلاصه یا چکیده
متن يادداشت
Wheat and corn starches were phosphorylated at various initial pH's by roasting at 130C for 2 h with 5% sodium tripolyphosphate (STPP) in the presence of 5% sodium sulfate. At pH 10, a wheat starch phosphate with 0.22% phosphorus (20% reaction efficiency) was obtained, which showed good thickening power and good stability of paste consistency. The best corn starch phosphate (0.16% P, 13% reaction efficiency) was obtained at an initial pH 11 with 5% STPP. Phosphorylation of starch below pH 9 with STPP showed almost totally monostarch phosphate; cross-linking was insufficient to stabilize the starch pastes. Wheat and corn starches were also phosphorylated with a mixture of 5% STPP and 2% sodium trimetaphosphate (STMP) in the presence of 5% sodium sulfate. The most viscous and shear-stable products were obtained at an initial reaction pH 9.5. However, phosphorylation using STMP with the two phosphate salts was extremely sensitive to pH, especially above pH 9.5. Paste clarity of the phosphorylated starches indicated cross-linking of starch with STMP began to accelerate rapidly above pH 8, but with STPP above pH 10. P-NMR spectroscopy was used to locate the phosphate esters on a wheat starch phosphate (D.S. 0.014) prepared by roasting the starch with 5% STPP in the presence of 5% sodium sulfate at an initial pH of 6. Spectra were measured on the usd\alphausd-limit dextrins and the usd\alphausd,usd\gammausd-limit phosphodextrins prepared from the starch phosphate using B. amyloliquefaciens usd\alphausd-amylase and A. niger glucoamylase. The P signals of several model compounds were recorded for comparison, including usd\alphausd-D-glucopyranose phosphates, methyl usd\alphausd-D-glucopyranoside phosphates and limit dextrins from amylose phosphate. It was concluded that the wheat starch phosphate had mainly C-6 and C-3 phosphate esters in a ratio of 2:3, and most substitution occurred along the linear segments of usd\alphausd-1,4 linked AGU's. The endogenous phosphate groups in potato starch also were detected on C-6 and C-3 in a ratio of 4:1. The P-NMR spectrum of the usd\alphausd-limit dextrin of potato starch showed the nonreducing end of the usd\alphausd-limit phosphodextrins contained all the 3-phosphate esters, but none of the 6-phosphate esters. The presence of 6-phosphate on the internal and the nonreducing AGU's in the usd\alphausd,usd\gammausd-phosphodextrin showed localized C-6 phosphorylation in potato starch, but isolated C-3 phosphorylation.
موضوع (اسم عام یاعبارت اسمی عام)
موضوع مستند نشده
Agricultural chemicals
موضوع مستند نشده
Biological sciences
موضوع مستند نشده
Food science
موضوع مستند نشده
Food science
موضوع مستند نشده
Phosphorus-31-NMR
موضوع مستند نشده
Pure sciences
نام شخص به منزله سر شناسه - (مسئولیت معنوی درجه اول )
مستند نام اشخاص تاييد نشده
P. A. Seib
مستند نام اشخاص تاييد نشده
S. T. Lim
دسترسی و محل الکترونیکی
نام الکترونيکي
مطالعه متن کتاب وضعیت انتشار
فرمت انتشار
p
اطلاعات رکورد کتابشناسی
نوع ماده
[Thesis]
کد کاربرگه
276903
اطلاعات دسترسی رکورد
سطح دسترسي
a
تكميل شده
Y
