Purification of Citrus Peel Juice and Molasses

Citrus peel juice and molasses are extremely bitter and unpalatable byproducts of orange and grapefruit juice production. Major components of interest are soluble sugars, glucose, fructose, and sucrose, which account for 60−70% of the dry solids. Analyses indicate that the remaining components are suspended tissue fragments, proteins, organic acids, mineral ions, phenolic compounds, and polyols. A purification sequence that removed a majority of bitter limonoids and phenolic compounds by adsorption on nonionic, macroporous resins was tested. Residual phenolic compounds were removed by adsorption on activated carbon or anion-exchange resin, which also removed anions of organic and inorganic acids. Taste panel results suggested that debittered products could be acceptable for food uses. Keywords: Citrus molasses; orange peel; bitterness; adsorption; macroporous resins