The study authors: K. O. Falade, O. C. Aworh. Department of Food TechnologyUniversity of Ibadan. The results of research on "Adsorption isotherms of osmo-oven dried african star apple (Chrysophyllum albidum) and african mango (Irvingia gabonensis) slices" conducted by K. O. Falade, O. C. Aworh (Falade, K.O. & Aworh, O.C. Eur Food Res Technol (2004) 218: 278. doi:10.1007/s00217-003-0843-8).



Halves of deseeded and deskinned pulps of African star apple (Chrysophyllum albidum) at three different stages of ripeness were immersed in sucrose solutions of 44°B, 52°B and 60°B in water baths at 27 °C and 40 °C for 8 h. About 10 mm slices of African mango (Irvingia gabonensis) at two different stages of ripeness were immersed in osmotic (sucrose) solutions of 52°B, 60°B and 68°B in water baths at 27 °C and 40 °C for 10 h. The adsorption isotherms of the osmo-oven dried fruit pieces were conducted at water activities between 0.1 and 0.9, at 20 °C and 40 °C. Higher equilibrium temperature and solids gained in the osmo-air dried pieces caused a depression of the adsorption isotherms, especially at low and intermediate a_w range. Crossing of the 20 °C and 40 °C isotherms for both African star apple and African mango occurred at a_w ~0.8. Sorption data was fitted into eight isotherm models. Guggenheim–Anderson de Boer (GAB) model was best fitted (r²=0.912 for African mango, and r²=0.998) for modelling and calculation of the monolayer moisture (M_m) content. M_m content increased with increasing degree of ripeness and total solids of osmo-oven dated products. M_m decreased with increased temperature. M_m of African mango and African star apple was in the range of 2.91–6.55 and 7.66−16.04% d.b., respectively.

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The complete study "Adsorption isotherms of osmo-oven dried african star apple (Chrysophyllum albidum) and african mango (Irvingia gabonensis) slices" (K. O. Falade, O. C. Aworh):

Adsorption isotherms of osmo-oven dried african star apple (Chrysophyllum albidum) and african mango (Irvingia gabonensis) slices

Falade, K.O. & Aworh, O.C. Eur Food Res Technol (2004) 218: 278. doi:10.1007/s00217-003-0843-8