Determination of physicochemical, compositional, conformational and rheological properties of gum produced from sage seed (Salvia sclarea) at optimum conditions

In this study, physicochemical, conformational, compositional and rheological properties of the sage seed gum (Salvia sclarea) produced at different optimisation conditions were determined. Firstly, the effects of different temperature levels, times, seed:water ratios and pH levels were examined on the gum yield and determined the most effective two parameters as the temperature and the time. Central composite design was used to determine the effect of these factors and calculated the yield of the gum samples. Afterwards, the gum samples to carry out the analysis were produced and determined their physichochemical, conformational, compositional and rheological properties. According to physicochemical analysis results, the temperature and time parameters affected the physicochemical properties except pH values. According to crude fiber analysis, It was determined that sage seed gum was used as a source of potential fiber. Moreover, according to phenolics values, It was specified that sage seed gum had high amount of phenolics more than the gums which took part in the literature. Therefore, antioxidant properties of gum were fairly higher than the other gums. The peaks which were obtained as a consequence of the FT-IR analysis showed an alteration according to temperature and time parameters. According to the obtained peaks, It was determined that the gum contained galactose, mannose, arabinose and rhamnose. On the purpose of carrying out the rheological analysis, steady, frequency and three interval thixotropic test (3ITT) were applied. Herschel Bulckley, Power-law and Second order structural model were applied to determine steady, frequency and three interval thixotropic test (3ITT), respectively. The maximum viscosity value of gum was obtained from the gum samples extracted at 85°C, 1 hour. When analyzed viscoelastic properties of gum, all of the samples dominated their elastic-like behaviour under the 0.1 Pa strain. Second order structural model was applied to third interval of 3ITT and according to the results of tests all of the samples showed viscous-like behaviour. In addition, the deformation and recovery percentage of samples were determined and maximum and minumum deformation and recovery rate were specified. Even though purification step applied to gum extracted from sage seed is inadequate, mannose to galactose ratio results determined with sugar analysis by HPLC revealed that sage seed gum can be alternatively used as a thickening agent compared to commercially used guar gum.