The rheological, pasting, and gel textural properties of corn starch blended with date syrup (DS) or sugar (SG) were studied. The average amylose content of the starch was 27.8%. Corn starch gel is considered elastic since the elastic modulus (G') was much greater than the viscous modulus (G″). Different effect between DS and SG on corn starch gel was observed, where SG addition and DS replacement experiments exhibited the highest G'. The tan δ of all samples was in the range of 0.02-0.20 indicating elastic behavior since it is less than unity. The hardness of starch gel ranged from 13 to 146 g and 212-145 for DS replacement and DS addition, respectively. Unlike the replacement experiment, the addition experiment exhibited significant increase in peak viscosity, setback and pasting temperature (p > 0.05). The magnitude of the effect of DS on corn starch gel was more evident compared to SG. This was apparent by looking at the slopes of the linear regression of the log of G' or G″ versus the log of frequency. Based on the information provided here, date syrup application can expand to cover the baking and beverage industries.
Keywords: Corn starch; Date syrup; Pasting; Rheology; Texture.