Preparation of high dietary fiber powder from lemon juice by-products

Lemon ( Citrus limon cv Fino) juice industry by-products were used to obtain high dietary fiber powder. The effect of processing variables (direct drying, and washing previous to drying) on functional properties, fiber content and type, microbial quality and physicochemical properties of the fiber were evaluated. The obtained fiber powder had good functional, microbial quality and favorable physicochemical characteristics to be used in food formulations. Processing conditions affected fiber composition and properties. Water holding capacity was enhanced by washing (7 g water/g non-washed fiber powder; 12.6 g water/g washed fiber powder) and slightly decreased by the reduction in fiber particle size. Oil holding capacity (6.7 g oil/g fiber powder) was not affected by those factors. Acid detergent and neutral detergent fibers were highest in powder from washed lemon residue (23.73 and 32.91%, respectively). a w was lowest in washed lemon fiber powder (0.13). Washing prevented fiber browning during drying as reflected in color parameters. Washing water rinsed green components. Drying was the responsible for the decrease of bacterial populations (approx. 90% reduction in microbial counts).