The main reason for adding curing salts to meat and poultry is preservation. But processors are seeking alternatives as nitrates and nitrites have grown to have a negative connotation.

Pre-packaged meat cases continue to make room for the growing number of uncured charcuterie entering the marketplace. From bacon and ham to pepperoni and salami, processors are making use of a loophole in the regulations that allow for the addition of natural curing agents that enable an “uncured” claim.

Why? Because the active curing agents – nitrates and nitrites – have grown to have a negative connotation. For starters, they are lethal in large doses. They also have been shown to create carcinogenic substances in the body, hence the reason they are on Whole Foods Market’s unacceptable ingredient list. Interestingly, when nitrates and nitrites are added to meat indirectly, as an inherent component of another ingredient rather than as a manufactured isolated ingredient, Whole Foods Market and the all-natural food community say it’s OK.

Understanding the cure

Before modern-day refrigeration, salt was used to preserve perishable foods, such as fish, meat, poultry and even vegetables. In its unpurified and raw form, these salts contained other elements in addition to the sodium and chloride that today we know collectively as table salt. In sea salt, for example, one often finds saltpeter, which is also known as potassium nitrate. This compound is formed in rock outgrowth and makes its way into the salts found in the sea.

In time, scientists identified these nitrates, which they also learned get converted to nitrites by salt-resistant bacteria in meat and poultry. “Nitrites do the heavy lifting in curing,” says Jacob Burton, executive chef of Lake Tahoe’s Stella Restaurant, Truckee, Calif., and creator of the website StellaCulinary.com.

When nitrite meets water, it forms nitrous acid and nitric oxide. “In meat and poultry, these compounds combine with the protein myoglobin to form nitric oxide myoglobin,” says Jane Boles, associate professor of meat science, Montana State Univ., Bozeman, Mont. “This pigment is not stable until after cooking when the final cured pigment, nitrosylhemochrome, is formed. The cooked pigment is more stable, but is still sensitive to oxygen, temperature and light. This is why most cured products are vacuum packaged.”

Not only do nitrates and nitrites produce this desirable color, they also are responsible for adding a zingy, tangy flavor to meat. Curing also breaks down and tenderizes tough protein fibers, resulting in a compact yet tender texture.

Processors are exploring "natural curing," products that are inherently sources of nitrites and nitrates. Celery powder eliminates the need for artificial curing agents.


“But the No. 1 reason for adding curing salts to meat and poultry is preservation,” says Doyle Keffer, service applications manager-salt, Cargill, Minneapolis. “Curing prevents fats from going rancid, but most importantly, curing impedes the growth of harmful bacteria, such as Clostridium botulinum.”

Preservation and food safety are paramount. However, since the advent of refrigeration, the desirable flavor changes are the reason most consumers are attracted to salt-cured products.

Modern-day curing salts

Commercially produced curing salts are highly regulated and standardized to ensure consistency and efficient cure. “They are typically 6.25 percent isolated sodium nitrite and 93.75 percent sodium chloride,” Burton says. “They are also colored pink so that the user knows they are curing salts and not ordinary table salt. This is to prevent an overdose of the nitrite, which is lethal at 4 grams. One would never consume this much via a cure, but it is possible if applied to foods like table salt.

“Some commercially produced curing salts also contain sodium nitrate,” Burton says. “The nitrate will turn into nitrite over time, which is useful in long-cured products, such as prosciutto and some sausages.”

The nitrites provide the immediate cure, while the nitrates work on the meat later in the process, which can sometimes be as much as a year. This conversion from nitrate to nitrite gives the cure time to slowly work its way deep into meats.

The loop-hole

In efforts to appeal to natural-foods enthusiasts, processors are exploring what is known as “natural curing.” These products are free of chemical curing agents, but they are typically made with ingredients that are inherent sources of nitrates and nitrites.

The USDA defines an uncured product as one that has been preserved without the use of chemical agents. These products can be labeled “uncured,” “no nitrites added” or “no nitrates added,” very label-friendly terminology.

 

 

Uncured products can be labeled
"uncured," "no nitrites added or
"no nitrates," very label-friendly
terminology.

“The history of using spices to preserve food extends back to the early history of cooking,” says Joe Forsthoffer, director of corporate communications, Perdue Farms, Salisbury, Md., manufacturers of Coleman Natural products.

Coleman’s uncured meats, like most others in the market, rely on celery, one of the richest all-natural sources of nitrates/nitrites. Spinach and Swiss chard are also recognized as being concentrated sources.

“Coleman Natural brand consumers are looking for products that are free of nitrates and nitrites,” Forsthoffer says. “We are able to meet their expectation while maintaining the same high level of food safety and without compromising shelf-life requirements.”

Tom Brown, vice president, Florida Food Products Inc., Eustis, Fla., says, “Color and texture are two variables that have defined meat quality for generations and cannot be compromised, even when natural.”

Using locally grown celery, Florida Food Products invented a minimally processed, all-natural celery powder that eliminates the need for synthetic curing agents. “It provides curing and shelf stability in an easy-to-use powder format,” Brown said. “Its active ingredient is naturally occurring sodium nitrate/nitrite yet is labeled simply as celery powder.”

Blended with sea salt and sold in powder form, the ingredient is readily soluble in water. It can be applied to meat via marinade – by injection, tumble or soak – with other seasonings. Usage levels vary from 0.2 percent to 0.6 percent.

The company also markets a natural cure accelerator based on cherry powder and evaporated cane juice, with the active ingredient being ascorbic acid. “The naturally occurring ascorbic acid accelerates the cure to meet challenging process conditions,” Brown said.

France-based Naturex SA recently introduced a line of acerola cherry ingredients, including a natural cure accelerator. “Our acerola cherry powder is a natural curing enhancer,” says Baptiste Demur, business manager. “Put simply, it is a natural alternative to sodium erythorbate.”

Sodium erythorbate increases the rate of nitrite reducing to nitric oxide, thus accelerating the curing process while at the same time lowering residual nitrite levels. “It also enhances cured color stability over the shelf-life of the meat product,” Demur said. “Cherry powders standardized to high levels of naturally occurring organic acids serve the same functions. Consequently, natural curing can be completed more efficiently using cherry powder in combination with a natural alternative to sodium nitrate or sodium nitrite.”

Demand for natural ingredients will continue to grow.


At the 2014 IFT Annual Meeting + Food Expo in June, Naturex showcased an all-natural beef jerky concept cured with the company’s Swiss chard powder and enhanced with acerola cherry. It was further protected with the company’s rosemary extract to help maintain flavor freshness throughout shelf-life.

Sometimes colors are added to assist with visual appeal. The US Dept. of Agriculture recently approved a five-fold increase in the level of tomato lycopene allowed as a colorant in ready-to-eat (RTE) meat products. This increase allows tomato lycopene colorants from manufacturer LycoRed Ltd., Israel, to effectively replace FD&C Red #40 and carmine in a wide assortment of deli meats, sausages and hot dogs.

“The USDA decision changes the ballgame for us,” says Roee Nir, colorant business unit manager. “We now may offer RTE meat manufacturers dramatic color options that previously were only attainable with artificial or insect-derived colors.”

Both of the LycoRed clean-label colorants are acceptable for use in RTE beef, pork and poultry products, as well as RTE meats for the fast-growing kosher and halal markets. Kosher and halal rules forbid products colored with carmine.

“Cured meats can range in multiple hues, and this new regulatory approval allows processors to add red shades that range from blue tones to reddish-orange,” Nir says. “This works for both meats and meat analogs, which are typically gray after processing. The ingredient is pH independent and we have a grade that is especially designed for higher temperatures and fat content.”

The demand for natural ingredients in the meat and poultry industry will continue to grow. With charcuterie, the question “to cure or not to cure?” really comes down to ingredient selection, as nitrite is essential for color, preservation, taste and texture. “Cured meats – chemically or naturally – simply are delicious,” Burton concludes. 

Donna Berry is a contributing editor from Chicago and is the owner of Dairy & Food Communications.