Starch partial substitution by the extract from Gleditsia triacanthos seed: Rheological properties of combined system in water, phosphate and acetate buffer

LORENA SCIARINI; GABRIELA NOEL BARRERA; LAURA ITURRIAGA; URSULA LOSER; PABLO DANIEL RIBOTTA

Austria

Conferencia; ISEKI Food E-CONFERENCE on Food Texture and Rheology 2019; 2019

ISEKI-Food Association

The aim of this work was to study the effect of the starch substitutions with the extract obtained from Gleditsia triacanthos (Gledi) seeds on the dispersion viscosity-profiles and gel texture properties of systems prepared in water, phosphate and acetate buffer. Commercial wheat (Wstch) and corn (Cstch) starch and the powder obtained from the extraction of Gledi milled-seeds were used. The partial substitution of Stch by Gledi was evaluated from 3 dispersions samples (2%p/v) (Stch+Gledi: 1.85+0.15, 1.70+0.30 and 1.60+0.40) prepared in water, phosphate (PB) (pH:3.6) and acetate (AB) (pH:6.5) buffer. Guar gum was used as control system. The viscosity-profile was studied by RVA. The gels (RVA gelatinized-dispersions) were analyzed by a puncture test with a texture analyser after 24 h and 7 storage days at 5 °C. The partial substitution of starch by Gledi increased the viscosity-profile in the 3 chemical environments. Although, the viscosity-profile of the samples in AB were lower than in water and PB. No effect of partial substitution of Wstch by Gledi on gel brittleness/elasticity was observed in water. However, gel brittleness/elasticity was higher in PB and AB in the systems with the higher starch substitution. The Young?s Modulus and strength of the gels were reduced in the 3 chemicals environment. In relation to Cstch systems, partial substitution by Gledi decreased the gel strength and Young?s Modulus, and increased the gel brittleness/elasticity in the 3 chemicals environment, mainly in the systems with the higher starch substitution. After 7 storage days, the brittleness/elasticity of the Wstch gels in water and BF was not affected by the starch substitution by Gledi, but this parameter was reduced in BA. The gel strength and Young?s Modulus were reduced as a result of the starch substitution by Gledi. On the other hand, Cstch gels did not show any difference in the brittleness/elasticity in water and BF, but in BA this parameter was reduced by the starch replacement by Gledi. The gel strength was reduced in the 3 chemicals environment. The gel Young?s Modulus was not influenced, but the samples with the lower starch substitution in the 3 chemicals environments showed higher Young?s Modulus values. The starch partial substitution by the extract from Gledi improved the viscosity profiles during heating and cooling. The gel brittleness/elasticity was not strongly modified by Gledi. The Young?s Modulus and strength of the gel was reduced as a consequence of partial replacements.