Effects of Low Heat-Moisture Treatment in Prata Green Banana Starch (Musa AAB-Prata)

Green banana is a great potential source for starch. The functional properties of starch can be improved by applying various innovative and safe technologies with the physical modifications being most desired by maintaining granular integrity and not making use of chemical reagents. The objective of this study was to investigate the effects of physical modification by low heat-moisture treatment (HMT) using moisture contents of 15%, 20%, and 25% in Prata green banana starch (Musa AAB-Prata). The extraction yield of starch was 23.80 +/- 3.3%. The native starch showed a high amylose content (42.13 +/- 0.26%), which was reduced by HMT at 15 and 20% moisture. The HMT did not change the morphology and the degree of molecular ordering in Prata green banana starch granule observed by scanning electron microscopy and Fourier-transform infrared spectrometry, respectively. However, starch modification caused a significant reduction in the swelling power of the starches at the higher temperatures (70 degrees C to 90 degrees C), besides increasing the gelatinization peak temperature and reducing the gelatinization enthalpy determined by differential scanning calorimetry. On the pasting profile of Rapid Visco Analyzer, it was possible to verify that the HMT reduced peak viscosity, trough, breakdown, and final viscosity and increased the pasting temperature and time to peak viscosity, thereby indicating improvements in starch thermostability and broadening the starch application range in the food industry.