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PRODUCTION OF BETA-CAROTENE FROM WHEY BY BLAKESLEA TRISPORA
Abstract
The objective of the present series of investigtions was to determine the optimal culture parameters for growth and the production of (beta)-carotene by Blakeslea trispora in whey. Previous reports in the literature had indicated that B. trispora did not utilize lactose, the major carbohydrate in whey. Subsequent studies were conducted to promote lactose utilization by the mold, identify the appropriate lighting conditions for optimal carotenogenesis and determine the type of whey for most efficient (beta)-carotene production. Three concentrations of whey were hydrolyzed with either acid or lactase. After fermentation, (beta)-carotene content was greater in the controls (no acid or enzyme treatment) than in either of the hydrolyzed treatments. Dry mycelial weight increased in the hydrolyzed treatments and was greater as the concentration of whey was increased. Stock strains were sequentially transferred onto increasing concentrations of lactose. This process, acclimation, was conducted to stimulate production of (beta)-galactosidase. When grown in a concentrated whey substrate, the lactose acclimated strains produced more (beta)-carotene than the stock strains. To eliminate the sequential transfer of mycelia, the effect of short-term acclimation was investigated. Stock and lactose acclimated strains were grown in either tyndallized whey (TYN), autoclave sterilized whey (ASW), synthetic mucor medium (SMM) or 10% lactose broth (LAC) for 48 h. The growth in these substrates was inoculated into tyndallized whey. Results indicated that a short-term acclimation process did not increase (beta)-carotene production by the stock strains. The effect of illumination on growth and carotenogenesis by B. trispora grown in whey was investigated. Results indicated that the lactose acclimated strains produced the greatest quantity of (beta)-carotene when grown under continuous illumination for 48 h followed by 96 h darkness. Conversely, the stock strains produced the greatest quantity of pigment under constant illumination (11 f.c.). The production of (beta)-carotene by B. trispora was investigated in three types of commercially available whey. Washed and unwashed mycelia were inoculated into fresh fluid whey (FFW), spray-dried whey (SDW) or whey permeate (WP). Results indicated that the unwashed strain produced the most (beta)-carotene in FFW (stock) and SDW (lactose acclimated). When grown in WP supplemented with nitrogen, it was demonstrated that the lactose acclimated strains more efficiently assimilate inorganic nitrogen.
Subject Area
Food science
Recommended Citation
LAMPILA, LUCINA EMILY, "PRODUCTION OF BETA-CAROTENE FROM WHEY BY BLAKESLEA TRISPORA" (1982). ETD collection for University of Nebraska-Lincoln. AAI8217539.
https://digitalcommons.unl.edu/dissertations/AAI8217539