The effect of whole grain rye flour arabinoxylans on the physical and chemical characteristics of a low moisture baked good.

摘要

In recent years, greater emphasis has been placed on the health benefits of whole grains. Studies have shown that whole grains are a source of fiber, reduce the risk of cardiovascular disease, diabetes and stroke and may help achieve weight loss. Rye, a cereal typically consumed as a whole grain, possesses such benefits.;Arabinoxylans are non-starch polysaccharides comprised of a beta-(1,4) linked D-xylopyranosyl backbone with alpha-L-arabinofuranose units attached as side residues via the alpha-(1,3) and/or alpha-(1,2) linkages. These compounds are found in whole grain and are particularly high in whole grain rye flour. These compounds are purported to contributor to the many health benefits associated with whole grain rye. While there are many health benefits attributed to arabinoxylans, they greatly impact dough rheology and baking by binding water, softening the dough and altering gluten functionality.;The removal or alteration of a portion of the arabinoxylans via water extraction or enzymatic degradation will change their functionality significantly. This has been demonstrated in wheat systems including wheat doughs and wheat breads but fewer studies have been conducted utilizing whole grain rye flour in whole grain rye doughs and low moisture baked goods such as cookies. Therefore, it is hypothesized that the chemical structure of arabinoxylans in whole grain rye flour will affect the product attributes of low moisture baked goods such as cookies.;The hypothesis can be tested by characterizing whole grain rye flour arabinoxylans which have been water extracted or enzymatically degraded with a variety of enzymes including Bacillus subtilis, Aspergillus niger and arabinofuranosidase. In model dough systems, it is evident that the use of the enzyme Bacillus subtilis produces a dough which requires less water and is less viscous vs. a control. In a model cookie system, the addition of Bacillus subtilis produces a cookie with a larger geometry. The Aspergillus niger and arabinofuranosidase show some differences vs. the control sample using these test methods as well.