MOISTURE DIFFUSIVITIES OF MACADAMIA NUTS FROM LOEI AGRICULTURAL RESEARCH AND DEVELOPMENT LOEI PROVINCE THAILAND

Jagrapan  Piwsaoad; Chayapat  Phusampao; Sorod  Srimuanwai; Patsakorn  Detkhon

Authors

Jagrapan Piwsaoad Program of Physics, Department of Science, Faculty of Science and Technology, Loei Rajabhat University, Loei 42000, Thailand.
Chayapat Phusampao Program of Physics, Department of Science, Faculty of Science and Technology, Loei Rajabhat University, Loei 42000, Thailand.
Sorod Srimuanwai Program of Physics, Department of Science, Faculty of Science and Technology, Loei Rajabhat University, Loei 42000, Thailand
Patsakorn Detkhon Physics Research Laboratory, Department of Physics, Faculty of Liberal Arts and Science, Roi Et Rajabhat University, Roi Et 45120, Thailand.

Keywords:

Thin-layer drying, macadamia nuts, diffusivities

Abstract

This article presents the thin-layer drying of macadamia nuts, which was conducted under controlled conditions of temperature by using a convective air dryer. The 2,000 g of macadamia nuts were dried for the temperature of 40, 50, and 60C, with the air flow velocity of 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2 m s-1 until its final moisture content reach to 10% (d.b.). Besides the effects of drying air temperature and velocity, seven different thin-layer models were fitted to the experimental data of macadamia nuts. The Modified Handerson and Pabis model were revealed to be the best. The value of R2 of the Modified Handerson and Pabis model was 0.9992-0.9986, indicating good fit and RMSE were also good (0.25-0.70%). Moisture diffusivities of macadamia nuts have been determined experimentally and moisture diffusivities were found to increase with the increasing in drying air temperature.

References

Barrozo, M.A.S., Sartori, D.J.M., Freire, J.T. (2004). A study of the statistical discrimination of the drying kinetics equations. Food. Bioprod. Process., 82(C3): 219 - 225.

Ertekin, C., and Yaldiz, O. (2004). Drying of eggplant and selection of a suitable thin layer drying model. J. Food Eng., 63:349-359.

Hashemi, G., Mowla, D., and Kazemeini, M. (2009). Moisture diffusivity and shrinkage of broad beans during bulk drying in an inert medium fluidized bed dryer assisted by dielectric heating. J. Food Eng., 92(3):331-338.

Hossain, M.A. and Bala, B.K. (2002). Thin-layer drying characteristics for green Chilli. Drying Technology., 20(2):489-505.

Sadi, T. and Meziane, S. (2015). Mathematical modelling, moisture diffusion and specific energy consumption of thin layer microwave drying of olive pomace. Int. Food Res. J., 22(2):494-501.

Stephenson, R.A. and Cull, B.W. (1986). Vegetative flushing patterns of trees in south east Queensland. Scientia Horticulturae 30:53-62.