Quality and Storage Stability of Precooked Pork Head Bone Broth

In order to clarify the optimal storage temperature and storage period of prepared pork head bone broth, which was made using an autoclave, changes in color, pH, total bacterial count, thiobarbituric acid reactive substances (TBARS) value, total volatile basic nitrogen (TVB-N) content, droplet size, ζ-potential, and microstructure were examined during storage at -3, 4, or 10 ℃. The results showed that during the whole storage period irrespective of storage temperature, the color gradually deepened, the pH was significantly reduced, the total bacterial count, TBARS value, TVB-N content and droplet size were significantly increased, the absolute value of the ζ-potential was significantly reduced (P < 0.05), and microstructural aggregation occurred. All quality indexes changed significantly faster at 10 ℃ than at -3 and 4 ℃. On the 25^th day at 10 ℃, the total bacterial count reached 6.76 (lg (CFU/g)) , and the TVB-N content was increased significantly up to 20 mg/100 g; while the total bacterial count remained at a lower level for up to 60 days at -3 ℃ and for up to 35 days at 4 ℃, and the broth maintained better quality characteristics. In conclusion, the bone broth can be stored at 10 ℃ for only 25 days, but as long as 60 and 35 days at -3 and 4 ℃, respectively.