Impact of drying methods on textural/rheological attributes of insoluble fraction of Persian gum

Abstract

Persian gum from the almond tree that produces sticky and viscous solutions. Insoluble fraction of Persian gum (IFPG) solutions were recovered and dried by different methods including freeze drying and oven drying at two temperatures, 45 °C to 65 °C. The influence of these drying methods on the textural and rheological characteristics and color of the insoluble fraction of Persian gum were studied in current research. At a shear rate of 75 s–1, the apparent viscosity of the dried-IFPG solution was achieved between 0.21 and 0.26 Pa s. The IFPG solution-apparent viscosity decreased from 0.26 to 0.16 Pa s., as the hot temperature increased from 45 °C to 65 °C and the drying method changed (freeze drying). The achievements indicate the suitability of the Herschel-Bulkelley model for modeling the flow behavior of the insoluble fraction of Persian gum (IFPG). The drying conditions of the insoluble fraction of Persian gum caused an effect on the textural change of the IFPG-gel and the highest amount of texture parameters related to hardness, cohesiveness, fracturability and adhesiveness of IFPG-gel were 0.0441 N, 7.816, 0.0156 N and 0.53 N s, respectively. 45 °C oven dried IFPG demonstrated a color with less brightness than others. So, the effective use of this gum is in the production of edible and coating films, food emulsifier, stabilization, improvement of rheological properties, stabilization, improvement of textural properties, improvement of viscosity and reduction of syneresis.