Abstract: Dry-cured hams were produced by intensified high-temperature ripening at 36 ℃ for 45 days with 6.5% salt curing. Changes in the salt and moisture contents, pH, color, myoglobin oxidation, and haem pigments and Zn porphyrin Ⅸ (Zn-PP Ⅸ) of semimembranosus were examined during processing. Furthermore, the color formation of dry-cured hams was studied and the effect of NaCl replacement with KCl on the color change during processing was examined. The results showed that there was no significant difference (P > 0.05) in physicochemical indicators, color parameters, and the content and state of red pigments between the control and 30% NaCl substitution with KCl. The unique color of dry-cured hams was formed by a combination of the oxidation state of myoglobin, red pigments contents and the state of muscle tissue. The relative contents of oxymyoglobin (OMb) and metmyoglobin (MMb) increased by about 22.07% and 25.21%, but deoxymyoglobin (DMb) decreased about 47.27%. L* value was significantly positively correlated with the relative content of DMb (P < 0.01) and negatively with the relative contents of OMb and MMb (P < 0.01) and it was significantly affected by the ratio of OMb to MMb (P < 0.01). In the low range (0%–27.49%), the higher relative content of MMb could result in a bigger a* value, and MMb had a bigger impact on a* value than did OMb. The contents of haem pigments and Zn-PP IX increased by about 394% and 5 296% during the processing of dry-cured hams and were significantly positively correlated with a* and C values (P < 0.01).

Key words: dry-cured ham, partial replacement with KCl, high-temperature ripening, color