Novel front end processing method of industrial beet juice extraction for biofuels and bioproducts industries

Abstract

Conventional raw beet juice extraction in food-grade crystal sugar production is a highly involved and energy intensive process, which includes beets washing, thawing of frozen beets, cossettes slicing, and high temperature denaturation and diffusion. Industrial beets, a new feedstock bred for non-food industrial use, processing for biofuel and bioproducts applications can use less stringent quality requirements and simplify the juice extraction process. A novel simplified front end processing (FEP), which is less expensive, energy efficient, and involved only common equipment (hammer mill and basket press), was developed and tested. The hammer mill pulverized the beets and basket press extracted the juice. Four beet conditions (fresh, frozen, thawed and fresh-frozen) and four presses with water addition were tested for juice extraction. The juice concentration had decreased with the increased number of presses, and the fitted exponential equations (R2 ≥ 0.97) determined the juice concentration as a function of number of presses. Frozen beets consistently produced significantly high concentration juice followed by fresh-frozen, thawed, and fresh beets. Freezing had a beneficial effect in increasing the cumulative approximate sugar extracted. Two presses for fresh (92%) and three for frozen (97%) beets extracted the most available sugars. Future research may focus on water temperature, beet particle size, juice for extraction, microbial stability, energy economics, and products utilization. This new FEP efficiently extracts industrial beet juice and has direct scope in industry deployment as well as enhances the potential of the fuel generated being recognized as an advanced biofuel by the renewable fuel standards.