Characterization of the textural properties of spreadable pistachio nut products

Pistachio spreads were prepared by homogenization of different compositions of honey and concentrated pomegranate juice (CPJ). Mixtures were examined with different methods such as instrumental, rheological and analytical methods by using texture analyzer and rheometer. Also, a hedonic test was run to get correlative results to these methods. Flow behaviors of all raw materials were determined and applied in four different models. In color measurements, as expected, the addition of ingredients such as honey, CPJ and milk fat lightened the pistachio paste. Frequency sweep test (FST) was done to obtain the ideal stress for rheological measurements. The creep test has given the elasticity concept for all mixtures with assisting the stress relaxation test. Texture profile analysis (TPA) was taken care out to observe how spreads behave. In addition to TPA, the spreadability test was performed to check how much force needs to be applied for the spreading of pistachio spreads. The response surface method was used to acknowledge about effects of ingredient ratios on the firmness of spreads. Results indicated that the Herschel-Bulkley model was found to describe the flow behavior of pistachio puree better than other models. Sensory analyses were performed to correlate the results of instrumental methods.