USE OF VISCOELASTIC MODEL TO DESCRIBE WATER ABSORPTION OF BEANS DURING SOAKING

S.M. Shafaei, A.A. Masoumi
Beans are a source of protein and a good alternative in animal feed. Grain soaking in hulling and cooking processes for the purpose of pericarp softening and water absorption is an ordinary practice. The rate of grain-water absorption varies with soaking. Water temperature affects the state of water absorption. Experiments indicated that the water absorption process of seeds consists of two phases. The rate of water absorption of the initial and secondary phases is high and low respectively. The main problem of all existing mathematical models for water absorption, such as the Peleg model, is that none of them assess for the second phase. Therefore, in this study the viscoelastic model, which is able to analyze water absorption in the second phase for crops, was used to predict the water absorption of beans during soaking. The model was carried out to predict the moisture content of three cultivars of bean (‘Talash’, ‘Sadri’ and ‘Mahali Khomein’). The experiments were carried out at three temperatures (5, 25 and 45°C) in triplicate using distilled water. The amount of water absorption by various seeds was determined 5, 10, 15, 30 min and one hour after immersion. The tests were followed at intervals of one hour for gelatinized seeds. The viscoelastic and Peleg models of moisture absorption were fitted to experimental data. Constants of both models were determined by data-fitting using MATLAB software for each sample at each temperature. To compare the viscoelastic model to the Peleg model, three parameters: the coefficient of determination (R2), chi-square (x2) and root mean square error (RMSE), were used. The results showed that the viscoelastic model was sufficiently accurate to predict the moisture content of the beans during soaking and there was no significant difference between the two models (P<0.05).
Shafaei, S.M. and Masoumi, A.A. (2014). USE OF VISCOELASTIC MODEL TO DESCRIBE WATER ABSORPTION OF BEANS DURING SOAKING. Acta Hortic. 1054, 191-196
DOI: 10.17660/ActaHortic.2014.1054.22
https://doi.org/10.17660/ActaHortic.2014.1054.22
immersion, moisture content, Peleg model, water absorption, mathematical model
English

Acta Horticulturae