INVESTIGADORES
PONCE Nora Marta Andrea
artículos
Título:
Characterization of Acid-Extracted Pectin-Enriched Products Obtained from Red Beet (Beta vulgaris L. var. conditiva) and Butternut (Cucurbita moschata Duch ex Poiret)
Autor/es:
ELIANA N. FISSORE; NORA M. A. PONCE; MARINA DE ESCALADA PLA; CARLOS A. STORTZ; ANA M. ROJAS; LIA N. GERSCHENSON
Revista:
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
Editorial:
AMER CHEMICAL SOC
Referencias:
Lugar: Washington,; Año: 2010 vol. 58 p. 3793 - 3800
ISSN:
0021-8561
Resumen:
Chemical and rheological characteristics of fractions enriched in soluble dietary fiber are reported.These fractions were obtained through acid hydrolysis of butternut (Cucurbita moschata Duch exPoiret) and red beet (Beta vulgaris L. var. conditiva) cell wall enriched powders. Hydrolysis wasperformed using citric acid at different pH values and reaction times (2 and 3 h). Yields obtained forbutternut fractions were between 21 and 28 g/100 g; for red beet, yields were 24 and 31 g/100 g forpH 1.5 and 11 and 17 g/100 g for pH 2.0 for previously mentioned times; in general, the increase ofthe yield was directly correlated with the decrease of pH and the increase of reaction time. Productsenriched in low methoxyl pectins were obtained in all cases. At the lowest pH assayed, pectins wereessentially constituted by homogalacturonan; a significant content of neutral sugars was determinedat the higher extraction pH. Neutral sugars were constituted mainly by arabinose, galactose,rhamnose, and glucose in different proportions for each fraction; in general, butternut fractionsshowed high glucose contents. Flow behavior for 2.00% (w/v) aqueous systems of the differentproducts was evaluated. Data obtained for fractions isolated at pH 1.5 fit to Herschel-Bulkley andCross models while those isolated at pH 2.0 fit to Ostwald and Cross models. All samples showedlow viscosity and, hence, poor thickening properties.