Effect of storage conditions on industrial sugar retention in energy beets

Abstract

AbstractEnergy beets could compete with corn grain as important industrial-sugar feedstocks for biofuels. However, long-term energy beet storage is necessary to maximize processing equipment use, and storage conditions may entirely differ from those established in the sugar industry. This work evaluated combined effects of surface treatment, temperature, and storage atmosphere on beet sugar retention. Initially, beets were dipped in solutions of either a senescence inhibitor (N6-benzylaminopurine) or one of two antimicrobial agents (acetic acid and pHresh 10.0r) at weight fractions of 0.05 and 0.1%, and 0.1 and 1%, respectively. Beets were then stored for up to 36 wk either under aerobic conditions or in sealed containers, at 6ºC or 25ºC. Surface treatment did not show a statistically significant effect on sugar retention. Aerobic storage at 25ºC enabled initial beet sugar retention due to dehydration caused by low relative humidity (37%) in air. In contrast, aerobic storage at 6ºC enabled sugar retention for 24 wk; however, sugar retention decreased sharply thereafter to 56%. This decrease coincided with mold appearance on beet surfaces. Beets stored in sealed containers at both temperatures retained 38% of initial sugars. Increasing surface area to better incorporate preservatives into beet tissue could improve long-term sugar retention.