Dry-cured ham is still produced by traditional methods. Controlling the amount of salt in the final product is not as straightforward as in other products. This is mainly because the amount of salt in the final product is highly dependent on the variability in salt intake, which is influenced by the ham characteristics and processing procedures. Therefore, the main approaches explored have been to modify the ham characteristics, the processing procedures or a combination of both. Here are some examples and their results.
- Reducing maturing time and increasing temperature
Meat with different pH, salting times and ageing temperatures was examined. The main findings were as follows.
- Hams with shorter salting times showed lower salt content, but intramuscular fat and protein content was not affected. Proteolysis decreased as salting time increased from 6 to 10 days.
- Salting time and ageing temperature significantly affected the texture of the ham at particular stages during processing (i.e. hardness, pastiness, crumbliness, stickiness and fibrousness) of M. biceps M. femoris but not M.semimembranosus (which is a drier muscle). Hams salted for 14 days were harder than those salted for 6 days.
- Ageing at 30 °C for the last 10 days of the process reduced the soft texture problems caused by a reduction in the sodium content; however, storage at 30 °C did not reduce softness in hams which had a low initial pH (<5.7).
- Metallic flavour in M.semimembranosus and sweetness in M.biceps femoris were higher in hams salted for 6 days.
- There was a tendency for muscles which had a low pH to show highest pastiness and adhesiveness; however, adhesiveness and pastiness were lower in hams salted for 14 days (Gou et al., 2008).
- Salt reduction, partial sodium replacement and change in post-resting temperature
The effect of different post-resting temperatures (5, 15 and 25 °C) was assessed using (i) NaCl reduction (from 30 g/kg to 15 g/kg) and (ii) NaCl reduction and addition of K-lactate (19 g/kg).
- In both formulations, longer post-resting times achieved higher drying levels, which were also negatively related to temperature. In other words, temperature accelerated the drying process.
- NaCl content was almost double in hams with standard salting.
- The addition of K-lactate increased cut surface darkness.
- A slight increase in adhesiveness was found in hams with salt reduction.
- Dry-cured hams with standard NaCl content were significantly saltier, more piquant and less sweet.
- A more intense metallic flavour was found in hams kept at low temperatures. However, increasing post-resting temperature above 5 °C reduced the processing time and the metallic flavour, but at 25 °C the hams spoiled (Costa-Corredor et al., 2009).
- Partial replacement of sodium with other salts
The effects of partially substituting sodium chloride with (i) potassium chloride and (ii) calcium chloride and magnesium chloride were evaluated.
- Total salt content (on a dry matter basis) was higher when using KCl.
- Water content was lower in hams salted with KCl; as water content affects total weight lost, hams salted with CaCl2 and MgCl2 had lower weight loss and higher water activity.
- The Na/K ratio was lower in the hams than in the salt mixture, indicating that that K+ penetrated the muscle more than Na+. However, there was a higher penetration of the inner muscles by sodium than by magnesium and calcium.
- No significant differences in colour and texture parameters were found between theformulations. However, there could be a risk of increased pastiness in hams with the CaCl2 and MgCl2 formulation.
- Sensory analysis was not carried out (Alino et al., 2010).
Can you think of any reason why KCl and NaCl should penetrate the muscle quicker than CaCl2 and MgCl2?