Quality of Dry-Cured Hams Produced from Pre-Frozen Hams as Affected by Mechanical Tenderization and Vacuum Packaging

Abstract

Fifty frozen hams were thawed for 3 d at 2–3°C, skinned and partially defatted. Half the hams were passed twice through a Ross Industries needle tenderizer and half were not tenderized. All hams were dry-cured for 16 d with a mixture of salt, sugar, sodium nitrate and sodium nitrite. Cores of 2.54-cm diameter were obtained from the cushion of 5 hams from each group weekly for 5 weeks. Outer, middle and inner portions of the cores were analyzed for salt and nitrite. After curing, all hams were held at 13°C for 14 or 15 d for salt equalization. The intact hams were smoked and aged at 24°C until a yield of 82% or less was achieved. Half the hams in each group were then placed in vacuum bags and half were left uncovered. All were aged 4 additional weeks at 24°C. Hams were cut and examined visually, by a palatability panel, by shearing and by analyzing a center slice for moisture, salt and nitrite. Tenderization allowed faster salt and nitrite absorption but resulted in slightly lower flavor and overall satisfaction scores. Tenderized hams achieved the required 18% weight loss (82%) approximately 10 d sonner than non-tenderized hams. Vacuum packaged hams had higher final yields and contained a higher level of moisture and lower level of salt than non-vacuum packaged hams. Shear values in semitendinosus muscles were greater for tenderized than for nontenderized hams while shear values in biceps femoris muscles were higher in non-vacuum packaged than in the vacuum packaged hams. Aerobic and yeast and mold counts were higher while lactobacillus counts were lower in non-tenderized than in tenderized hams. Aerobic and lactobacillus counts were higher in vacuum packaged than in non-vacuum packaged hams. In general, tenderization allowed faster curing and aging while final aging in vacuum bags allowed higher yields.