Study of Salted Octopus Drying Kinetics and Hygroscopy from Artisanal Fishing in Agadir Region

Abstract

Salt-and-dry technique is an artisanal fish conservation method adopted in the Maghreb countries which is based on lowering the water activity. This latter factor is crucial in food preservation, where the relationship between the water activity and the water content of the salted octopus helps control its storage. However, the realization of this processing in controlled conditions is limited by the lack of information regarding the drying time and the behavior towards humidity of this specie. This work describes the drying kinetics by plotting the drying curve (70 ° C; 1.5 m/s) and helps define the salted octopus drying time. Also it presents the desorption and adsorption isotherms at three temperatures which represent the storage temperatures (30, 40 and 50°C) following the gravimetric method. The drying of the salted octopus carried out helped reduce the water activity to a value of 0.63 and the water content of 0.505 g water/g MS during 10 hours. In addition, the sorption curves were experimentally determined and modeled by polynomial regression of order 4. The fitting has given correlation coefficients close to 1 for the three temperatures.