CHANGES IN PHYSICOCHEMICAL PROPERTIES AND VOLATILES OF PORK BALANGU AS POSSIBLE INDICATORS OF SPOILAGE DURING AMBIENT TEMPERATURE STORAGE

Balangu is a traditional Nigerian grilled meat normally prepared from beef, and this study was aimed at producing it from pork. Changes in its physicochemical properties and volatiles were determined during storage at 30C. Solid phase mass extraction gas chromatography-mass spectrometry analysis showed identification of 71 volatiles belonging to different classes of compounds. Principal component analysis indicated that ethanol, 3-hydroxy-2-butanone, 3-pentanol, 2-butoxyethanol, 1-hydroxy-2-butanone, 2-heptanone, un-decane, 2-ethyl-furan, butoxylactone and 2,3-butanedione were among the principal volatiles identified. Thiobarbituric acid (TBA) value and free fatty acids increased from 0.38 (mg malondialdehyde/kg) and 0.58 (KOH/g lipid) to 0.68 and 0.69, respectively, during storage. Conclusively, the volatiles associated with the pork Balangu were heterogeneous, some of which may be indicators of spoilage in the product. Organoleptically acceptable Balangu could be produced from pork; however, the results of TBA and sensory evaluation indicate that the product's shelf life may not exceed 2 days. PRACTICAL APPLICATIONS Balangu is a Nigerian traditional grilled meat product consumed by many people as delicacies, mostly during leisure. Producers of the product do not normally exhaust their sales on the day of production, thereby leaving remains until the second day or beyond; and unfortunately due to poor storage facilities, the remains are kept at ambient temperature of approximately 30C. This temperature may encourage spoilage by opportunistic microorganisms and have adverse effect on the physicochemical properties of the product. This practice of storing the product at ambient temperature usually results in its rejection by customers, although it has not been reported in the literature. The knowledge of the physicochemical properties and volatiles would be useful toward probable improvement in sensory quality of the product in future studies, especially with the use of biological or chemical agents that possess antioxidant properties and are considered safe in food uses.