The physical and sensory properties of snack crackers prepared with oat and wheat bran

Adequate intake of dietary fiber is of increasing concern to Americans, especially with recommendations by nutritionists and health professionals to consume more complex carbohydrates and fiber. Scientific research supports health benefits from physiological effects of specific fiber types. Oat bran, in particular, has increased in popularity due to its cholesterol-lowering effects. Consumer interest in nutritionally-enhanced foods is growing as indicated by market reports. In response to increased demand for high fiber foods, a study was conducted to investigate the effects of adding bran to snack crackers. Physical and sensory properties of crackers containing oat or wheat bran at four flour replacement levels, 0, 10, 20, and 30%, were studied.

Physical parameters reflecting textural quality of crackers were measured and found to give varying results. Breaking strength was significantly affected (p<0.01) by bran level but not by type; crackers decreased in breaking strength as level of bran increased. Stack height decreased as level of bran increased in wheat bran crackers but flakiness was more constant for oat bran crackers. Water activity, which has been correlated with textural quality of snack foods, did not differ significantly among treatments.

Physical measurement of color attributes revealed significant (p<0.001) treatment effects. Lightness and yellowness decreased as bran level increased, especially for wheat bran crackers. Redness increased gradually in both oat and wheat crackers as bran level increased. Overall, color was more consistent across all bran levels for oat crackers than wheat crackers.

Crackers made with 10 and 20% bran were analyzed for fiber and found to range in total dietary fiber from 8.48 to 18.51 g/100g. Oat bran crackers contained less dietary fiber than wheat bran crackers at 10% but not 20% levels.

A 6-member, trained sensory panel found significant differences (p<0.05) among treatments for color, crispness, cohesiveness, and flavor. Oat bran crackers were more consistent for color than wheat bran crackers. Judges perceived oat bran crackers to be less cohesive than wheat bran crackers. As bran level increased cereal flavor was less intense for oat bran crackers. A 50-member consumer panel found no differences in acceptability or preference between 10% oat bran and 10% wheat bran crackers with hedonic and food action rating tests. Acceptability of both oat and wheat bran crackers was low, possibly due to poor textural quality of crackers.