Graduation date: 1977

Call number: LD2668 .T4 1953 L53 / Master of Science

Call number: LD2668 .T4 1953 W65 / Master of Science

The factors determining the generation of aroma in starch extrudates containing added ingredients with aroma precursors were elucidated. Analyses were performed using headspace analysis of raw materials and extrudates and subsequent analysis by Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Olfactometry (GC-O. Study I described the volatile, amino acid and fatty acid profiles of Hydrolised vegetable protein (HVP)and Soy protein isolate (SPI). Studies II, III and IV descibed the volatiles developed from extrusion of different feedstocks under mild and extreme processing conditions. Wheat starch was chosen as the carrier.A comparison of the influence of the three different ingredients HVP, SPI and glucose, added to the starch feed, showed the formation of Strecker aldehydes and Maillard-type compounds were significantly affected by the addition of these ingredients. The work in this thesis demonstrated that the addition of ingredients such as HVP, SPI, glucose, cysteine, cysteine-HCI, modifies the aroma of wheat starch extrudates. Furthermore, it showed the changes in conditions of extrusion and pH will greatly influence the aroma profile of the products. / Doctor of Philosophy (PhD)

xvii, 214 leaves : ill., graphs, tables ; 29 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Physiology, 1980

No description available.

Nitrogen is essential to obtain high yields of winter wheat in south coastal British Columbia, which includes Vancouver Island and the lower Fraser Valley. An accurate recommendation for N application is required to keep input costs down for most economical returns and to limit environmental problems related to leaching of excess N. The questions are how much, when and which form of N should be applied to winter wheat. The general objective of this study is to improve our understanding of winter wheat growth and N uptake. This study monitors the soil N supply and characterizes the plant development, dry matter accumulation, and N uptake of winter wheat in South Coastal B.C.. Also, it compares the effectiveness of conventional and intensive crop N management and urea and ammonium nitrate sources of fertilizer N under intensive crop management. A series of field experiments was conducted in 1986-87 and 1987-88 with winter wheat to evaluate conventional and intensive N management in the area. Additionally, a N source study was carried out in the latter year to compare ammonium nitrate and urea. Soil N supply for winter wheat ranged from 52 to 151 kg N/ha through the two years of field experiments at five sites. Available N in the 0-50 cm soil depth varied from 10 to 100 kg N/ha through the growing season in the different treatments. An accurate estimate of N behavior involves N accumulation in the crop. During the early spring until harvest, the crop dry matter yield and N uptake patterns were plotted. The grain yields ranged from 4 to 9 t/ha for the conventional management (75 kg N/ha), and from 4 to 11 t/ha for the intensive crop management (I.CM. 225 kg N/ha) system. Between the conventional and I.CM., there was no significant difference in grain yield but there was in quality, specifically grain protein. Grain protein ranged from 8.2 to 9.7% for the conventional and from 10 to 13.7% for the I.CM. treatment. Also, there was no difference in grain yield or quality between ammonium nitrate and urea fertilized plots at final harvest. However, in the early stage at GS31, crop took up more N from ammonium nitrate (97 kg N/ha) than from urea (75 kg N/ha) and soil mineral N levels with urea were higher than with ammonium nitrate. / Land and Food Systems, Faculty of / Graduate

No description available.

The objective of this study was to examine the effects of two thermal processes, drum-drying and thermoplastic extrusion, on protein quality and digestibility of whole wheat. Coker 916 whole wheat flour was made into a simulated whole wheat spaghetti by extrusion cooking (single screw, 50 psi, 93°C) and a flaked product by drum-drying (152°C). Protein Efficiency Ratios (PER) of the original whole wheat kernels and the two processed wheat products were determined. The apparent digestibility of the four diets was determined from Kjeldahl nitrogen analysis of feces. Amino acid composition, available lysine analysis, colorimetry (Hunter L, a, b color values), and Differential Scanning Calorimetry were also conducted to investigate the effects of thermal processing on protein quality. Both thermal processes significantly increased protein digestibility while PER’s of the drum dried flakes (1.66) and unprocessed whole wheat (1.59) were significantly greater than the extruded product (1.42) Thermal processing also resulted in substantial reductions in lysine (>10%) and several other essential amino acids. Hunter L, a, b values indicated that the drum-dried flakes were lightest in color, followed by the unprocessed whole wheat and the extruded product. The observed decrease in lysine and PER of the extruded product may be due in part to Maillard Browning, as indicated by Hunter color values. It appears that total lysine or Hunter L color values may be reasonable predictors of protein quality of processed whole wheat. DSC results suggest that starch was fully gelatinized during drum-drying of the whole wheat but on partially gelatinized during extrusion cooking. / Master of Science

The majority of wheat research in the world and in Canada is conducted by the public sector. The government of Canada has introduced legislation to update its plant breeder’s rights (PBR) legislation, making Canada compliant with the International Union for the Protection of New Varieties of Plants (UPOV) 91 convention, with the goal to stimulate private investment in wheat variety research. International experience with UPOV 91 reveals a wide range of outcomes depending on the specific royalty setting mechanisms allowed within their domestic legislation. This thesis compares Canada’s existing policy to three very different international examples (France, United Kingdom, and Australia) of UPOV 91 compliant royalty collection systems for wheat. The model presented is one of a monopolistic competitive wheat-breeding industry with the introduction of a new certified seed variety. Farmers have the option to use farm saved seed (FSS) or certified seed on their farm. The additional economic benefit created from the innovation and its distribution is analyzed and interpreted for both, farmers (social benefit) and breeders (private benefit). The results of the analysis show that while each UPOV 91 compliant model generates more revenue for farmers and breeders than Canada’s current policy, they tend to generate less than expected revenue in the short-run. If a country has strong intellectual property rights (IPRs), it will attract some domestic and foreign investment and possibly a beneficial collaboration between the public, private, and producer sector, also known as P4 (public-private-producer-partnerships).