The Asian noodle market is responsible for the increased volume of wheat imported to that region in recent years. Soft white wheat produced in the Pacific Northwest is mainly used for baked products, whereas an Australian wheat, Australian Standard White, is preferred for noodles. To enter this market soft white-wheat cultivars with properties similar to or better than Australian Standard Whitemust be developed. This process is difficult as little is known of the factors that influence noodle quality. The use of grain-protein percentage, kernel hardness, and six viscosity parameters measured by the Rapid Visco Analyzer for predicting Japanese udonnoodle quality was evaluated. The Rapid Visco Analyzer was developed to indicate quickly and reliably the starch properties of a small wheat sample. Experimental material included advanced winter-wheat selections from the Oregon State University wheat-breeding program and Stephens, a widely grown winter-wheat cultivar. Two commercial spring cultivars, Owens and Klasic, thought to have good noodle quality were used as checks as was straight grade flour milled from Australian Standard White wheat. The material was grown at two locations (Rugg and Chambers) which represent diverse environments and management systems. Protein content, kernel hardness, and six viscosity parameters (Peakl, Low, Peak2, Peakl-Low, Peak2-Low, Peakl-Peak2) were measured. A sensoryevaluation panel evaluated the end product for surface appeal, texture, and taste. Within each location differences were found for all traits except protein content at the Rugg site and surface appeal at the Chamber location. Between the two experimental sites the only traits for which no differences were detected were kernel hardness and surface appeal. Significant entry by location interactions were observed for kernel hardness, Peakl- Peak2, and the three sensory-evaluation traits. Kernel hardness and grain-protein percentage were not associated, however both were negatively associated with the viscosity parameters. Associations of grain-protein, kernel hardness, and the viscosity parameters with the sensory evaluation traits were not statistically determined. A softer kernel texture appeared most useful for predicting Japanese udon-noodle quality as determined by sensory evaluation. Grain-protein percentage was not a good indicator by itself, but each cultivar may have a protein-content range within which noodle quality is optimized. This range may be influenced by the kernel texture. The viscosity parameters did not appear useful for predicting noodle quality as determined by the sensory evaluation panel. A more sensitive sensory evaluation method may be required to detect small however important differences and different viscosity parameters should be investigated. Based on the sensory-evaluation data several experimental entries appeared promising in having the desired quality profile for Japanese udon-noodles. / Graduation date: 1994

Little is known about the effects of arabinoxylans (AX) on noodle quality. The aim of this study was to observe interrelationships between wheat flour AX, SRC tests, and noodle quality attributes, and to investigate the use of SRCs to predict cookie diameter. Cookie diameter is the most common index of overall soft wheat quality used in practice. Duplicate samples of 63 soft white wheat (Triticum aestivum) varieties and breeding lines grown at Corvallis in 2002 were selected to study the relationships between flour and noodle characteristics. Kernel hardness was positively correlated with starch damage, total AX and water-extractable AX (WEAX) content but negatively correlated with break flour yield. In this set of samples, despite significant correlations, the sodium carbonate and sucrose SRC tests were not considered to be reliable predictors of cookie diameter due to low numerical correlation coefficients. A modified extraction method for WEAX-SE and WUAX-SE was optimized and reduced in scale. During method development, WUAX 1-SE and WUAX 2-SE fractions that had been treated with protease and amylase respectively were observed using SEHPLC. The equivalent fractions had been discarded in other studies. In this study, AX was found to present in these fractions. A subset of 12 lines was used for further AX extraction. WUAX 2-SE had the highest molecular weight, followed by WUAX1-SE, and then WEAX-SE. The molecular weights of WEAX-SE ranged from approximately 411,305 and 447,282. However, molecular weight of WUAX 1-SE and WUAX 2-SE could not be specifically defined in this study. In addition, WEAX-SE contained a higher degree of substitution than WUAX 1-SE and WUAX 2-SE. For the whole sample set, flour protein content was negatively correlated with ti5A cooked noodle hardness, adhesiveness and chewiness but positively correlated with springiness. At the very low flour protein contents of this sample set, protein composition, which related to lactic acid SRC, became more important for noodle texture. Both starch damage and sodium carbonate SRC were positively correlated with cooked noodle hardness and chewiness at t₀ and t [subscript 15A] Total AX and WUAX were positively correlated with adhesiveness at to, which might result from gummy and sticky characteristics of AX. Using the subset of 12 lines, described above, increased xylose and arabinose contents reflected overall higher AX abundance, and were related to harder kernel texture, poor milling properties. They were also related to higher water, carbonate and sucrose SRCs, and smaller cookie diameter. A/X ratios of WEAX-SE and WUAX 1-SE were positively correlated with flour yield and break flour yield. The WUAX 2-SE fraction seemed to behave different from the WEAX-SE and WUAX 1-SE fractions. The relationships between A/G ratio, and milling characteristics and SRC were opposite to A/X ratios for all fractions. Decreased MW and increased abundance of WUAX in this sample set was related to poorer milling characteristics. There appeared to be no direct systematic relationships between AX and cooked noodle texture parameters in this study. However, AX content appeared to affect noodle texture indirectly, mediated through the effects ofAX on kernel hardness, milling properties, starch damage, reduced FSV, and hence harder noodle texture. Kernel hardness index, flour yield, break flour yield and tisw cooked noodle hardness were able to be predicted with some confidence using stepwise multiple regressions that used selected parameters from the WEAX, WUAX 1-SE and WUAX 2-SE fractions. / Graduation date: 2004