In this study, the effect of icing medium containing different concentration of pistachio ( L. cv. Akbari) green hull extract (PHE) was investigated on the chemical stability of rainbow trout. The fishes were stored for 12 days in flaked ice containing 0, 0.1, 0.2 and 0.3% PHE and the parameters of pH, total volatile base nitrogen (TVB-N), histamine, free fatty acids, peroxide and thiobarbituric acid index (TBA-i) were periodically evaluated. In all experiments, a significant difference was evident between control and fish muscles stored in ice containing PHE. Fish icing with 0.3% PHE could considerably retard the oxidative and hydrolytic rancidity. In addition, it had significant effect on prevention of pH increase and production of volatile basic nitrogen during 12 days storage. PHE could diminish histamine accumulation in fish muscle and improve safety of rainbow trout. Consequently, PHE could have potential of application in icing medium for preservation of fish quality especially fatty ones.

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Assessment of fermentation as the heart of the bread making process is of significant importance. For this mean a variety of methods and devices have already been invented but have always faced drawbacks such as limitation in predicting and monitoring the fermentation in situ, due to fluctuating fermentation conditions. The aim of this study is manufacturing of a system for continuous, accurate and simultaneous monitoring of pressure and temperature of bread dough in real fermentation condition by means of in-contact measurement of dough pressure during fermentation. In this research a new method in terms of dough pressure and temperature measurement during fermentation was designed in which the instrument was given the name of "fermetron"; then its precision and correctness on different flours were validated according to reliable rheological tests using alveograph and rheofermentometer. Given the close trends among parameters of rheofermentometer and alveograph with those of fermetron, its validation in regard to monitoring dough fermentation was confirmed. The tests results, while confirming the accuracy and precision of the fermetron performance, show the significant effect of the flour sample quality on the process of fermentation. Fermetron exhibits the pressure evaluation results graphically. Each graph includes five main parts which is correspondent to dough state in terms of gas production initiation, gas production rate, gas retention, gas release, yeast activity end, and multistage gas release, respectively.