DRY BEAN (PHASEOLUS VULGARJS) COLOR STABILITY AS INFLUENCED BY TIME and MOISTIJRE CONTENT

The color stability of 32 lines of beans to which different levels of moisture were added was evaluated in an accelerated shelf-life testing chamber for up to 10 weeks using Hunter values and National Bureau of Standard (NBS) unit of color difference (± E) techniques. With pinto beans, Hunter L values decreased as storage time increased. Also, Hunter a values increased with time. However, Hunter b values did not change with storage. With great northern beans, Hunter a and b values were more important than Hunter L value. Similar to pinto beans, along with prolonged storage, great northern bean color changed. Pinto and great northern beans having an extra 10% added moisture showed much more color change than those of control or 5% moisture added beans. Finally, bean genotype was closely related with color stability in stored pinto and great northern beans.