Curing process offers great benefits for preserving meat. The term “curing” usually implies “preserved with salt and nitrite.”
Adding salt provides two safety benefits:
- Drains some water what results in less moisture that is available to bacteria.
- Creates salty environment which inhibits growth of spoilage bacteria.
- Swells proteins which release some rich meat juice. This juice mixes with salt and becomes sticky “exudate.” The exudate binds ground meat particles, fat and spices together.
Adding sodium nitrate to meat provides additional benefits:
- Prevents growth of pathogenic (dangerous) bacteria, notably infamous Clostridium botulinum.
- Develops pink color of meat.
- Develops "curing" flavor in meat.
- Retards fat rancidity (deterioration of fat flavor).
There are three methods of curing:
- Dry - salt, nitrite
- Wet - salt, nitrite, water
- Combination - salt, nitrite, water
To preserve meats without cooking them we have to use the drying process. Drying meat is based on eliminating water. Injecting meat with curing solution or immersing meat in curing solution introduces more water. For those reasons only dry curing method is suitable.
The dry cure method works fast and can be used under wider temperature range than other methods. The accumulating brine is drained away and not replaced, so there is a greater loss of weight than in other methods. Providing that a fresh meat is used it is a very reliable method as the salt layer acts as an impenetrable barrier to any bacteria on outside.
Today, meats are cured with sodium nitrite and they can be cured at refrigerator temperatures 36-40° F (2-5° C) as the process is not dependent on curing bacteria as was the case with sodium nitrate in the past. Although curing proceeds faster at higher temperatures, however, the growth of spoilage bacteria will be faster, too. This is why we cure meat at low temperatures.
All curing methods are covered in detail on our meat site.
Sodium nitrite comes in form of clear crystals which are dangerous as 1 g can kill a person. As they may be mistaken for common salt, they are not sold to public in pure form. Sodium nitrite is mixed with salt, and to distinguish the cure from salt, a pink coloring is added. It is sold in the US as Cure #1 or Cure #2.
Cure #1 is a mixture of 1 oz of sodium nitrite (6.25%) to 1 lb of salt. It must be used to cure all meats that will require smoking at low temperatures. It may be used to cure meats for fresh sausages (optional).
Cure #2 is a mixture of 1 oz of sodium nitrite (6.25%) along with 0.64 oz of sodium Nitrate (4%) to 1 lb of salt. It is usually used for products that will be air cured for a long time like country ham, salami, pepperoni, and other dry sausages.
US Maximum Limits for Applying Cures
Adding Cure #1 to cooked meats and regular sausages made from ground (comminuted) meat:
|Comminuted Meat (Sausages)||Cure #1 in ounces||Cure #1 in grams||Cure #1 in teaspoons|
This amount of Cure #1 corresponds to adding 156 ppm (parts per million) of pure sodium nitrite to 1 kg of meat.
These are the maximum limits and it is up to you how much you want to add, however, meat needs at least 75 ppm of sodium nitrite for any meaningful curing.
Adding Cure #1 to dry meats and sausages:
|Meat for Dry Products||Cure #1 in ounces||Cure #1 in grams||Cure #1 in teaspoons|
This amount of Cure #1 corresponds to adding 625 ppm (parts per million) of pure sodium nitrite to 1 kg of meat. It is up to you how much you want to add, however, adding 156 ppm of sodium nitrite (2.5 g of Cure #1 per 1 kg of meat) would be a good starting point.
For dry meat products and sausages you can add Cure #2 instead of Cure #1.
The reason that there are much higher allowable nitrite limits for dry cured productsis that nitrite dissipates rapidly and the dry cured products are air dried for a long time. Those higher limits guarantee a steady supply of nitrite.
Curing Meat for Dry Sausages
Traditional Curing Method. Depending on particle size, meat needs usually 2-3 days curing time. Ground meat may be cured in 1-2 days. For regular (cooked) smoked sausages meat was usually cut into 1-2 inch long cubes, mixed with salt and Cure #1 and then cured in refrigerator for 3 days. After that it would be ground,mixed with spices, stuffed and processed.
When starter cultures are added to meat, the meat can be cured inside of the casing. Starter culture introduces millions of bacteria of the desired type which immediately jump into action. This eliminates the question whether meat has enough curing and lactic acid bacteria. Those numbers are very small to begin with and that is why the 48-72 hours of curing time should help bacteria to grow. Unfortunately, spoilage bacteria will grow as well, however lactic acid bacteria can stand salt much better than other types so the overall balance is in our favor.
When starter culture is added ground meat can be mixed with salt, cure #1 or 2, sugar (if added), spices and immediately stuffed. The curing will take place inside the casing as the sausage will be dried for a long time.
Keep in mind that regular sausages are made with about 1.8% salt, but dry sausages need 3% salt. This extra salt is needed to prevent spoilage bacteria from taking over the process and ruining the meat.
NOTE Curing Meat for Regular (Cooked) Sausages
Although meat cured by the traditional curing method will result in product of the highest quality, nevertheless the latest trend is to stuff the ground meat immediately into the casing and allow the meat to cure there. Such sausages should, however, be conditioned for 1-2 hour at room temperature before being smoked or cooked. This conditioning step provides more time for sodium nitrite to react with myoglobin and develop pink curing color. Needless to say, a bigger cut ofmeat requires more curing time, otherwise a slice of ready to eat product may gave pink and grey colored areas.
For more about curing, nitrates, nitrites, American and European cures.
There is also a calculator that calculates the amount of cure for different nitrite (ppm) levels: