Chemical, physical, and sensory attributes of snap beans as they affect texture

Author

Beverly Dawn Buckner

Date of Award

12-1990

Degree Type

Thesis

Degree Name

Master of Science

Major

Food Science and Technology

Major Professor

John R. Mount

Committee Members

J.L. Collins, P.M. Davidson

Abstract

Ten cultivars of snap beans, grown in Tennessee, were evaluated for chemical and physical characteristics before and after processing and to determine the correlation between chemical and physical differences and sensory perception of texture. The beans were processed by canning and freezing.

The proximate composition of the fresh beans was 93% moisture and (on a dry weight basis) 17.1% crude protein, 2.1% ether extract, 7.1% ash and 72.8% NFE. Canned beans increased in moisture (93.5%) and ash (22.4%) (salt added) while frozen beans decreased in moisture (92.5%) and ash (6.3%). Fresh snap beans contained 380 mg/100 g (dwb) calcium and 262 mg/100 g (dwb) magnesium. Canned beans decreased to 259 mg calcium and 136 mg magnesium while frozen beans increased to 505 mg calcium and contained the same amount of magnesium.

Fresh and canned beans contained 32.0 and 31.8 percent total dietary fiber, respectively, and both were significantly lower than frozen beans, (34.0%). The frozen bean also contained significantly more pectin, 5.1 mg/g, than did canned beans, 4.2 mg/g. Both canned and frozen beans contained small amounts of fibrous material, less than 0.03%, which is less than the maximum legal limit of 0.15%.

Canned beans were significantly softer (27 Kg force to shear 100 g sample) than fresh or frozen beans (326 Kg and 340 Kg force, respectively). As pectin content of the beans increased the firmness of the beans also increased (r=0.83). However, the total dietary fiber did not significantly correlate with the firmness. A sensory panel was not able to significantly determine differences in texture between 'BBL- 47’ and ‘FM128' snap beans. These two cultivars had been selected based upon differences in firmness for the frozen products.

None of the snap beans had significant amounts of sloughing (0.1-1.0 ml sediment/ 100 g) and the average seed content of the snap beans was 5.7%. The color of the snap beans was comparable to these cultivars from previous studies.

Recommended Citation

Buckner, Beverly Dawn, "Chemical, physical, and sensory attributes of snap beans as they affect texture. " Master's Thesis, University of Tennessee, 1990.
https://trace.tennessee.edu/utk_gradthes/7144