Moisture Sorption Characteristics of Dambu-nama – A Nigerian Dried Meat Product

Abstract

Moisture sorption characteristics of traditional Dambu-nama (control) (TDBN) and laboratory Dambu-nama (LDBN), a cooked, pounded, shredded and dried Nigerian meat product, were determined at four different temperatures (10oC, 20oC, 30oC and 40oC) and relative humidities of 10 – 96% using the standard static, gravimetric method. The GAB, Oswin, BET and Henderson sorption models were tested to fit the experimental data. Both adsorption and desorption isotherms were sigmoidal in shape (type II). EMC decreased with increase in temperature (ranged 7.3496 at 10oC to 4.3189 at 40oC) but increased with increase in water activity (7.3496 at water activity of 0.1471 to 47.7869 at water activity of 0.9554) respectively. The percentage root mean square (% RMS) for LDBN and TDBN for both adsorption and desorption were best described by GAB model, followed by Oswin and Henderson. Net isosteric
heat of desorption (122.71 kJ/mol) were found to be greater than those of adsorption (68.5 kJ/mol) at low moisture content.