Physicochemical, Rheological and Sensory Properties of Different Brands of Sesame Pastes.

Abstract

The chemical characteristics, rheological properties and sensory evaluation of nine different brands of the sesame pastes were investigated. The sesame pastes showed a significant difference for the crude fat, protein, crude fibre, total sugars, total ash, moisture content, and acid values (p < 0.05). The fat content ranged from 51.80% to 61.56%, and the protein content varied between 16.08% and 18.97%. All sesame paste samples are pseudoplastic materials. The flow indexes lied between 0.67 and 0.81 for the tested sesame pastes (p > 0.05). The consistency coefficient of the different sesame paste brands varied significantly (p < 0.05), ranging from 4.48 to 24.21 Pa・sn, indicating that the consistency coefficient is a more sensitive parameter for measuring the flow behaviour of foodstuff. The areas of the hysteresis loops of the white-sesame paste of "Haoweisi" brand and the black-sesame paste of "A Yimeng couple" brand were higher than the other sesame pastes, indicating that these two samples were difficult to be restored to their original structures and such restoration required a longer time. Both Storage modulus (G') and loss modulus (G″) of the sesame pastes increased with increasing frequency, and G' values were greater than the G″ values, exhibiting the typical properties of the viscoelastic solid, the results may provide the valuable reference for choosing the sesame pastes as the spreadable butters or salad dressings, and for further processing.