Rheological properties and sugar composition of locust bean gum from different carob varieties (Ceratonia siliqua L.).
The seeds of the main Italian carob varieties, Latinissima and Tantillo, and those of two selected accessions of Latinissima were evaluated in terms of yield, rheological properties, and sugar composition of the endosperm (LBG). The separation of the seed components in Latinissima and its seedlings yielded meanly 52.2% gum, 17.4% germ, and 30.5% tegument, whereas Tantillo furnished a lower gum yield (38.5%) and a higher yield of tegument (45.8%). The viscosity of 1% LBG aqueous solutions was measured at different shear rates (3-60 rpm), pH values (3.0-6.0), and temperatures (10-60 degrees C). The best results were shown by Latinissima, whereas Tantillo provided always the poorest thickening capacity. The content of free simple sugars and sucrose in the raw flours, the total monosaccharide residues after acidic hydrolysis, the mannose/galactose ratio, and the distribution of polysaccharides by size exclusion chromatography accounted for the observed viscosities. The seeds of Latinissima showed the highest technological potential.
Rizzo
Valeria
V
Dipartimento di OrtoFloroArboricoltura e Tecnologie Agroalimentari (DOFATA), Università degli Studi di Catania, Via S. Sofia 98, 95123 Catania, Italy.
Tomaselli
Filippo
F
Gentile
Alessandra
A
La Malfa
Stefano
S
Maccarone
Emanuele
E
D002241:Carbohydrates / Q000032:analysis*; D007887:Fabaceae / Q000737:chemistry*; D005685:Galactans; D006863:Hydrogen-Ion Concentration; D008351:Mannans; D053149:Plant Gums; D011134:Polysaccharides / Q000737:chemistry*; D012212:Rheology; D012639:Seeds / Q000737:chemistry; D013045:Species Specificity; D014783:Viscosity
D002241:Carbohydrates; D005685:Galactans; D008351:Mannans; D053149:Plant Gums; D011134:Polysaccharides; C017471:locust bean gum