Thesis (M.S.)--University of Wisconsin--Madison, 1946. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1944. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 27-28).

Typescript, etc. / Digitized by Kansas State University Libraries

Bacillus subtilis α-amylase was used to hydrolyze starch from peeled and whole potatoes (Solanum tuberosum). Effect of gelatinization temperature, pH, enzyme concentration, temperature of hydrolysis and presence of calcium ions were investigated. Optimum conditions for hydrolysis were when α-amylase levels were 0.3 percent of the starch concentration in the presence of 400 ppm calcium at pH 7.0 and 80°C for 2 hr. After centrifugation to remove residual material, the supernatants were adjusted to pH 5.0 to 5.5 with 30 percent sulfuric acid and heated at 100°C for 10 min to inactivate α-amylase. Treatment with four percent activated charcoal decolorized the clear hydrolysate before the product was spray dried. The dried product was a light yellow powder, slightly sweet, relatively bland in taste and readily soluble in water. Dried potato hydrolysate made from peeled potatoes had a dextrose equivalent of 30 and contained 85 percent carbohydrates, 8.4 percent protein and 5.5 percent ash; while the hydrolysate from whole potatoes had a dextrose equivalent of 26 and contained 86 percent carbohydrates, 8.4 percent protein and 6.0 percent ash. The composition of the carbohydrates of the two hydrolysates were similar except the hydrolysate from peeled contained a higher concentration of glucose and lower concentration of saccharides with a degree of polymerization greater than four. At concentrations of greater than 40 percent, the potato hydrolysate made from whole potatoes did not show as high a viscosity as commercial corn syrup solids with a dextrose equivalent of 24; the potato hydrolysate adsorbed twice as much moisture as the commercial corn syrup solids at 75 percent relative humidity at 23°C for 30 days. Substitution of sucrose with whole potato hydrolysate in chocolate milk revealed that substitution of two parts of sucrose by two parts of potato hydrolysate could be used with a slight loss of desirability. Fifty and one hundred percent addition of whole potato hydrolysate to a commercial dehydrated vegetable soup mix showed no decrease in the desirability of the product. This work has shown that a useful potato hydrolysate containing significant amounts of protein can be prepared from either peeled or whole potatoes. / Graduation date: 1978

Inaug.-diss.--Münster. / Cover title. Lebenslauf. "Abdruck aus: 'Landw, jahrbücher' 1914, bd. XIVI, heft 5." "Literaturnachweis": p. 69-70.

Inaug.-diss.--Münster. / Cover title. Lebenslauf. "Abdruck aus: 'Landw, jahrbücher' 1914, bd. XIVI, heft 5." "Literaturnachweis": p. 69-70.

Thesis (M.A. in agricultural economics)--Washington State University. / Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1983. / Typewritten. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 126-147).

Thesis (M.S. in environmental science)--Washington State University, May 2010. / Title from PDF title page (viewed on June 14, 2010). "School of Earth and Environmental Sciences." Includes bibliographical references (p. 35-41).

A study involving variation in strains of the potato scab organism as isolated from a soil in British Columbia is reported. Associated with this is a study of soils from scab-free and scab-infested areas. Exchange capacity and related studies of a number of soil samples indicate a trend toward higher average exchange capacity, higher average exchange calcium and higher average calcium-potassium ratios in the samples from scab-infested areas. There is also a trend toward higher organic matter content and lighter soil textures in the scab-producing soils. In spite of these trends no definite correlations can be established under the method of soil sampling adopted. Thirty-four strains of Streptomyces scabies isolated from diseased White Rose tubers grown on the ranch vary markedly in cultural characteristics and in pathogenicity. The effect of hydrogen ion concentration on four of these strains shows a positive correlation between pH, amount of growth and hydrogen ion concentration up to the optimum pH of 7 to 8 and beyond this range a negative correlation exists. The inhibiting acid pH is 3.4 for two strains and between 4.0 and 5.5 for the other strains. The limiting alkaline pH appears to be beyond pH 11.6. Microphotographs of the Streptomyces scabies show typical open spirals and chains of conidia 0.5 to 1.0 microns in diameter. Scab control measures conducted in pots in the greenhouse and using a severely scab-infested soil sample from the ranch indicate no control by mercuric chloride applications. Applications of sulphuric acid, sulphur and calcium hydroxide indicate that a pH of 8.0 or greater is an effective but not complete control. An acid pH of 5.0 gives less control than pH 8.0 and more acidic reactions give even less control. The applications of these necessary to effect control are too high to be of practical value. The fungicidal effect of compound P-162 as determined under laboratory procedures is no indication of its efficacy in the field or greenhouse. Laboratory technique indicates that most strains are completely inhibited at 100 to 230 parts per million of compound P-162 while in the greenhouse tests 40 parts per million proved effective in giving partial control. The practical value of P-162 in the field is as yet to be determined since its commercial value and its usefulness as a control measure in the field is unknown. / Land and Food Systems, Faculty of / Graduate