title: Fermentation of Opuntia stricta (Haw.) fruits for betalains concentration.
abstract: Fermentation of juice and homogenized fruits of Opuntia stricta fruits has been developed and optimized. The aim was to obtain the red food colorant betanin from prickly pear, at high concentration and low viscosity. Among three strains assayed, Saccharomyces cerevisiae var. bayanus AWRI 796 has been the optimum for this process. The optimum temperature value was found to be 35 degrees C for both sugar consumption and pigment preservation. After fermentation, biomass and residual vegetal tissue were discarded by centrifugation. Supernatant was concentrated under vacuum. Therefore, liquid concentrated betanin was obtained, with low viscosity and being sugar free. Besides, bioethanol was obtained as byproduct. Characteristics of the final product obtained were pH 3.41, 5.2 degrees Brix, 9.65 g/L betanin, color strength of 10.8, and viscosity of 52.5 cP. These values are better than obtained by other procedures.
authors.affiliation: Departamento de Ingenieria Quimica y Ambiental, Universidad Politecnica de Cartagena, Cartagena (Murcia), Spain. rosario.castellar@.upct.es
authors.forename: M R
authors.initials: MR
authors.lastname: Castellar
authors.forename: J M
authors.initials: JM
authors.lastname: Obón
authors.forename: M
authors.initials: M
authors.lastname: Alacid
authors.forename: J A
authors.initials: JA
authors.lastname: Fernández-López
mesh_terms: D050859:Betacyanins / Q000032:analysis; D050858:Betalains / Q000032:analysis*; D001628:Beverages / Q000032:analysis; D050260:Carbohydrate Metabolism; D004396:Coloring Agents / Q000032:analysis*; D005285:Fermentation; D005638:Fruit / Q000737:chemistry / Q000378:metabolism*; D029747:Opuntia / Q000737:chemistry / Q000378:metabolism*; D010936:Plant Extracts / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013696:Temperature
chemical_list: D050859:Betacyanins; D004396:Coloring Agents; D010936:Plant Extracts; D050858:Betalains; C020228:betanin