%0 Journal Article
%T Effect of Maltodextrins on the Rheological Properties of Potato Starch Pastes and Gels
%A Les£¿aw Juszczak
%A Dorota Ga£¿kowska
%A Teresa Witczak
%A Teresa Fortuna
%J International Journal of Food Science
%D 2013
%I Hindawi Publishing Corporation
%R 10.1155/2013/869362
%X The study examines the effects of maltodextrins saccharified to various degrees on some rheological properties of potato starch dispersions. Pasting characteristics, flow curves, and mechanical spectra were determined for native potato starch and for its blends with potato maltodextrins having dextrose equivalents (DE) of 10.5, 18.4, and 26.5. The results showed that medium-saccharified maltodextrin (DE = 18.4) gave the strongest effect, manifesting itself as a considerable reduction in the viscosity at pasting, a decrease in apparent viscosity during flow, and a decrease in the storage and loss moduli. Addition of high-(DE = 26.5) or low-(DE = 10.5) saccharified maltodextrins had a markedly smaller effect on the rheological properties of starch. The differences in the effects produced by the maltodextrins are closely connected to the degree of polymerisation of the maltooligosaccharides in the systems. 1. Introduction Starch, one of the most common polysaccharides, has a number of specific properties that make it highly useful in the food industry and other sectors of the economy. It belongs to the cheapest thickening agents, texturizers, filling agents, and stabilizers. Heating starch granules in water environment causes them to paste. When they release amylose in the process, starch loses its specific granular structure [1¨C3]. The characteristic pasting temperature depends on botanical origin of starch as well as on the presence of other substances in the system. Sugars present in a starch suspension reduce the water activity of the system and stabilize the amorphous regions of the granules. As a result, starch pasting temperature increases and rheological properties of the system change [4¨C7]. The greater this effect, the higher the concentration of the solution and the greater the molecular weight of the substance added [3, 8, 9]. In the temperate climatic zone countries, such as Poland, potatoes are an important source of starch. Potato starch differs from cereal starches mainly in the size and structure of granules [10, 11], amylose content, phosphorus content, and manner of phosphorus bonding, as well as in fat and protein contents [1, 12¨C14]. Since natural properties of starch are not always advantageous in terms of technology and application, it is often subjected to various modifications, among them hydrolysis. Such a modification may produce maltodextrins, that is, carbohydrate polymers built of D-glucose units having a dextrose equivalent (DE) of under 20 [15, 16]. In Poland, starch hydrolysates with a DE of 20 to 30 are called
%U http://www.hindawi.com/journals/ijfs/2013/869362/