Assessment of meat drying in hot humid climates using natural convection, closed-type solar dryers and investigation of practicable meat drying parameters

Abstract

Two natural convection closed-type solar dryers (Cabinet and Tent) were constructed and evaluated in comparison with ambient drying method for their drying performance on different meat strip sizes in the hot humid climatic zone of West Africa, viz Accra, Ghana. Results from the studies indicated the following: Ambient drying method and the modified TSD (in Experiment 3) showed the desired functions for the initial drying stages of meat strips. The CSD showed the desired functions for later drying stages of meat strips. The effect of increased ventilation to the drying chamber of the TSD was to increase the rate of moisture removal from drying meat strips in the initial drying period. The increased ventilation however~ led to lowered temperature increases in the drying chamber and consequently lowered drying performance of the TSD during later drying period of meat strips. lxl cm raw meat strips dried and stored better than lxl cm. brined and 2x2 cm. raw and brined dried meat strips, when stored at room temperature in aerobically sealed plain LDPE bags during a 6 week storage period. Consequently, 1 cm thick meat strip seemed to be the critical meat size to dry under the present conditions of study. Brine, (containing 3-5 or 10% salt) infusion of meat strips for short or long periods prior to drying, adversely affected moisture removal from drying meat strips and subsequently shortened the storage life of the dried product. Gelatine coated (1O% gelatine solution preparation at 40°C) and hot smoked (ca. 50°C for 30 minutes) solar dried meat strips, aerobically sealed in plain LDPE bags and stored at room temperature had greatly extended shelf life during a 6 month storage period. All dried meat strip sizes studied rehydrated to more than half their original weight during a 6 hour rehydration period in water at room temperature. Sensory evaluation on dried meat strips cooked in a traditional soup indicated better meat flavour and acceptability than when cooked in ordinary water