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Effect of polyphenol oxidase on discoloration of rolled noodle products

Woojoon Park, University of Nebraska - Lincoln

Abstract

Three sets of wheat samples were investigated for quality factors related to Asian raw rolled noodle production. The sets included forty advanced experimental hard white wheat lines from two different Kansas locations (Sample Set 1); eight hard white wheat samples from California, Colorado, and Idaho (Sample Set 2); and ten hard red wheat varieties grown at three Nebraska locations (Sample Set 3). Variation in wheat and flour quality characteristics were influenced by varietal characteristics, environmental conditions, and/or wheat classes. Variation in wheat and flour Chromameter L (whiteness), a (redness), and b (yellowness) values was significantly (P $<$ 0.05) affected by growing location or variety. Sample Set 2 provided wheat with brighter and yellower color than Sets 1 and 3. A rapid and simple qualitative wheat discoloration test was developed. This wheat discoloration test may be used as a screening tool for eliminating early generation wheat lines with very high polyphenol oxidase levels or as a means to moderate the influence of polyphenol oxidase on noodle quality attributes. A quantitative method also developed in this study may generate baseline data on currently grown wheat varieties for polyphenol oxidase levels. Variation in wheat and flour polyphenol oxidase activity may be partially due to varietal characteristics or environmental conditions. Noodle color values at storage times of zero, 6, and 24 hours were different among varieties and growing locations. Noodle storage time had a significant (P $<$ 0.05) influence on noodle L, a, and b color values. Noodles made from Sample Set 2 had higher weight and volume gains with less cooking loss and shorter cooking times than those from Sample Set 3. Polyphenol oxidase activity was related to noodle color, resulting in a decrease in brightness and an increase in yellow color. Agronomic quality characteristics, proximate composition, and wheat and flour color appeared to be related to noodle discoloration during storage. However, the influence of wheat and flour quality characteristics on noodle color varied among each sample set.

Subject Area

Food science|Agronomy|Analytical chemistry

Recommended Citation

Park, Woojoon, "Effect of polyphenol oxidase on discoloration of rolled noodle products" (1995). ETD collection for University of Nebraska-Lincoln. AAI9604432.
https://digitalcommons.unl.edu/dissertations/AAI9604432

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