Food Chemistry Advances (Dec 2023)
Rheological and textural properties of sohphlang (Flemingia vestita) starch gels as affected by heat moisture treatment and annealing
Abstract
Sohphlang being a tuberous crop exhibits rheological properties, which are expected to change with treatment. The main aim was to study the influence of heat-moisture treatment (HMT) and annealing (ANN) on rheological properties of sohphlang starch. HMT was done for 16 h using 20 %, 25 % and 30 % moisture levels, while ANN was performed at 70 %, 75 % and 80 % moisture levels for 24 h at 50 °C. Both HMT and ANN enhanced gel formation capacity and firmness. Starch gels presented a reduced apparent viscosity with an increase in shear rate, exhibiting shear thinning behavior. Frequency tests were well described by Power law and both HMT and ANN increased the structural gel strength. Starch gels containing 10 % of HMT-30 starch exhibited an improved elastic behavior (4289.79 Pa). Irrespective of starch concentration and for all samples, G′ > G″ was observed on heating beyond Tgel and during cooling, indicating the formation of rigid gel network. Gels prepared from 15 % of HMT-30 starch showed the highest resistance to temperature than other gels. HMT-30 showed more pronounced and significant changes in properties than ANN-80. The thermal stability of sohphlang starch gels may extend its application in foods requiring severe processing conditions such as pasteurized foods.
