Effects of amidated low methoxyl pectin on healthy restructured fish food from Mexican flounder (Cyclopsetta chittendeni)

Nowadays an increasing demand of functional foods exists. In the case of fish products, pectins can be added to offer an additional healthy value to the consumer with a positive effect in the textural properties. Therefore, it is possible to take advantage of species with low commercial value or that are captured incidentally and sacrificed by error, like Mexican flounder (Cyclopsetta chittendeni). The objective of this work was to determine the effect of the addition of amidated low methoxyl pectins (ALMPs) on the functional and mechanical properties of restructured fish products from Mexican flounder. Different concentration of pectins (0 as control, 10, 20, 30 or 50 g/kg) and degrees of amidation (5, 10 or 25%) were studied. The fish pastes obtained were incubated at 40C for 30 min before they were cooked at 90C for 20 min. Backward extrusion, expressible water (E_w) and color of fish pastes were determined, and treated gels were characterized by changes in mechanical properties (texture profile analysis, puncture test and torsion test), E_w and color. Results obtained suggest that the ALMP with the highest degree of amidation increased mechanical properties and the water-holding capacity of fish gels. Gels containing 10 g/kg of 10 or 25% ALMP showed adequate mechanical and functional properties with almost no changes perceptible in color attributes. ALMP can be used to offer to consumers healthier fish foods based on mexican flounder.