Physico-chemical and mechanical thermo-rheological characterization of three varieties of triticale starches

Abstract

Nowadays, starch is an excellent biodegradable option instead of synthetic polymers, to avoid contamination. In this work, triticale starch from three varieties (Faraón, Peteroa and Aguacero) was isolated and the physico-chemical and thermo-rheological properties were evaluated. Also, mechanical properties of thermoplastic films using this starch were assessed. From the physico-chemical analysis it was found that the moisture, protein and lipids contents were slightly different among starches. Amylose value was similar. Thermo-rheological behavior measured by Mixolab® revealed that initial water uptake was higher for Faraón variety due to the grain morphology observed by Scanning Electron Microscopy (SEM). Values for gelatinization temperature obtained were 82.2 °C for Faraón starch, followed by Peteroa (72.0 °C) and finally Aguacero (65.6 °C). From the mechanical properties, Faraón thermoplastic starch (TPS) films showed the highest value of Young’s modulus (1.90 ± 1.09 MPa) for the composition 50/25/25  (starch/glycerol/water). The highest elongation at break (64.77 ± 14.14 %) was obtained for Peteroa composition 50/35/15 (starch/glycerol/water).  Then, triticale mainly used to feed animals more than for human consumption, could be good alternative for preparing biodegradable films with potential applications in agriculture and food packaging.