Moisture Sorption Studies using the GAB Model of a Beef Based Dambun Nama (A Ground Meat Product) Stored over a Period of Six Months

Abstract

Water adsorption isotherms of Dambun Nama, a ground beef product, were determined over a storage period of six months, at an average ambient temperature of 33.8oC and an accelerated temperature of 50oC, using the static gravimetric method. The study was aimed at establishing the moisture sorption profile of a traditional meat product Dambun Nama common in Northern Nigeria, produced from beef and stored over a period of six months. The sample was produced using a standardized method; it was sterilized, packaged in six airtight glass containers and stored at ambient temperature as the sample stock for the analyses over a period of six months. Data was generated from the sorption studies based on the isopiestic transfer method using concentrated sulphuric acid solutions. The isotherms are generally shaped like the type 4 isotherms for food products. Between 33.8oC and 50oC adsorption, the monolayer moisture content ranged from 0.036 to 0.048 gH2O/g solids, and between 0.037 to 0.049 gH2O/g solids for desorption. There was a general increase in the GAB constants K and C. The correlation coefficient (R) values obtained for adsorption ranged from 0.941 to 0.959, and for desorption, the values ranged from 0.940 to 0.957, indicating that the GAB model was suitable in describing the moisture sorption profile of Dambun Nama within the prescribed water activity ranges and storage period.