TITLE:
Characterization of Two Different Stumps of Spirulina platensis Drying: Assessment of Water Transport Coefficient
AUTHORS:
Eloi Salmwendé Tiendrebeogo, Alfa Oumar Dissa, Fabien Cherblanc, Issakha Youm, Jean-Claude Bénet, Aboubacar Compaoré, Jean Koulidiati
KEYWORDS:
i>Spirulina platensis, Isotherm Desorption, Stump, Water Content, Water Transport Coefficient
JOURNAL NAME:
Food and Nutrition Sciences,
Vol.6 No.15,
November
23,
2015
ABSTRACT: The sorption behaviour and water transport mechanisms inside Spirulina platensis samples were experimentally analysed during isothermal drying at 25℃ and 50℃. Two different products grown in semi-industrial farms from Burkina Faso and France with initial water contents respectively of the range from 2.73 kg w /kg dm to 3.12 kg w /kg dm were characterized. A novel procedure has been developed to determine the water content profiles inside samples during isothermal drying. At both temperatures, experimental results underlined that the physical properties of Spirulina are not sensitive to the geographical origin, Burkina-Faso or France. To keep Spirulina at an water activity below 0.6 in order to preserve it from micro-organisms development, sorption isotherm curves show that a sufficient requirement is to lower the water content until an upper limit of w = 0.075 db. The evolution of water transport coefficient as a function of water content highlights a monotonous exponential dependence with a transport coefficient ranging from 1.70 × 10–10 to 94 × 10–10 m2/s. The contribution of solid phase shrinkage to the transport of water is negligible for the last drying steps.