The Effect of Soy Flour as a Natural Antioxidant on Flaxseed in Yeast Bread

The effect of soy as a natural antioxidant against flaxseed rancidity in yeast breads was tested. Variables included: control (100% bread flour); yeast bread with 15% flax meal in place of part of the total bread flour; yeast bread with 15% flax meal and 5% soy; and yeast bread with 15% flax meal and 10% soy. Objective and sensory tests were used to evaluate breads. Peroxide values indicated that the hydroperoxides in breads increased during the first four weeks of the study, and then decreased, as would be expected as breads are exposed to more elements with time. Moisture content was not significantly different between the breads. Breads containing flax were significantly firmer (p < 0.02) in texture. Breads containing flax were also significantly lower in volume (p < 0.005) and significantly darker in crumb color (p < 0.01). The level of 10% soy contributed to a significantly darker crust color (p < 0.04). Quantitative descriptive analysis (QDA) found the level of 10% soy also contributed to an increased stale taste and aftertaste, firmer texture, coarser crumb, and drier loaf (p < 0.05). Musty aroma was not significantly different among breads and all breads containing flax had an increased grainy taste (p < 0.0001). Soy was found to have no significant antioxidant effect on the prevention of flaxseed rancidity in yeast breads.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Human Nutrition, Foods, and Exercise

Department dc:contributor.department

Human Nutrition, Foods, and Exercise

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2004

Author dc:creator

• Davis, Sarah Farthing

Chair dc:contributor.committeechair

• Conforti, Frank D.

Committee members dc:contributor.committeemember

• Marcy, Joseph E.
• Niba, Lorraine L.

• Oxidation
• antioxidant
• yeast bread
• flaxseed
• soy

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

etd-11092004-124045

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/35641