MOLECULAR WEIGHT PROFILES OF DIETARY FIBER PRODUCTS OBTAINED BY CHEMICAL OR ENZYMATIC MODIFICATIONS OF Cucumis moschata, Duch. MESOCARP

FISSORE ELIANA; RUMILLE SANDRA; MATKOVIC LAURA B; WIDER EVA A; ROJAS ANA M; GERSCHENSON LÍA N

Helsinski, Finlandia

Conferencia; Dietary Fibre 2006: Multifunctional complex of components; 2006

University of Helsinki

Molecular weight (MW) profile of the cell wall polysaccharides (CWP) that constitute  dietary fiber products obtained by chemical (B, 0.5 M-sodium citrate buffer; pH 5.2) or enzymatic (hemicellulase H, or cellulase, C) modification of pumpkin (Cucumis moschata, Duch) mesocarp were studied through a Sepharose column with 0.5 M-imidazol buffer (pH 7.0). Total carbohydrate content into each collected fraction was determined by phenol-sulphuric method. Rheological characterization of fractions obtained was performed in a Brookfield viscometer (25ºC). C-product was constituted by polysaccharides of the highest (homogeneous) MW range determined. H was constituted by CWP of the lowest MW range determined, with a uniform MW-distribution. B-product was characterized by an heterogeneous MW distribution. B, C and H-fractions were water soluble after swelling and the 1% (w/w)-B solution produced a transparent gel with thinning behavior at room temperature, while C showed lower consistency and acted as a thickener only after heating and addition of sucrose (60%, pH=3). Conversely, H-product showed newtonian behavior and a low viscosity. Cellulase or chemical modification of CW material of pumpkin mesocarp produced dietary fiber products (C, B) with interesting functional properties for food technological applications. – Este trabajo fue retirado por los autores por imposibilidad financiera de asistir.