Whether it's freshly grated Parmesan on pasta or a salad topped with crumbled Gorgonzola, a little cheese adds texture and flavor to many dishes. But along with the bold flavor may come a dose of sodium, an essential ingredient in cheese that gives it form, flavor and safety.
People began using salt to create cheese as early as 5,000 years ago when nomads in central Asia and the Middle East discovered milk curdled by gastric enzymes within animals' stomachs. The nomads preserved the naturally soured and curdled milk by draining off the watery whey and salting the concentrated curds. The earliest residue of cheese making outside of an animal's stomach was found in an Egyptian pot dated around 2,300 B.C.
Today, cheese is produced from milk — typically from a cow, goat or sheep — curdled or thickened by the addition of acid, rennet (a complex of enzymes) or specialized bacteria. The mixture separates into watery whey and semi-solid curds; the curds, which are mostly fat and protein, are drained and made more resilient by adding acid and salt, which also delays the development of decaying microbes. The controlled activity of the milk and microbial enzymes helps deconstruct protein and fat molecules into smaller fragments and impart flavor to the curds.
Thousands of varieties of cheese provide palates with unique tastes, textures and versatilities. Contingent upon the composition of milk, cheese production and type of cheese, nutrient profiles of cheese vary widely and may include different levels of protein, fat, calcium, magnesium, phosphorus, sodium, zinc, vitamins A, B2, B12, D and others.
The 2010 Dietary Guidelines for Americans recommend three cups per day of fat-free or low-fat milk and milk products and the DASH diet, extolled for successfully reducing hypertension, recommends 2 to 3 servings of non-fat or low-fat dairy products daily. Still, a number of organizations have singled out cheese for its contribution to total sodium in the diet. The Centers for Disease Control and Prevention cited cheese as one of the top 10 sources of sodium in the U.S. food supply in 2012.
The conundrum we face is how to balance food safety, flavor and functionality in cheese production without sizably adding to our sodium intake.
4 Basic Ingredients and Natural Cheese Production
The type of animal milk used in cheese production defines the cheese. Other factors include the animal's diet, microbes contained within the milk and whether the milk is raw or pasteurized. Cow's milk is neutral in taste and contains about 58 milligrams of sodium per 100 grams of cheese. Buffalo's and sheep's milk have higher fat and protein contents, are richer in taste and range in sodium from 35 milligrams to 58 milligrams per 100 grams. Goat's milk has less casein and produces more crumbly cheese, ranging from 41 milligrams to 60 milligrams of sodium per 100 grams of cheese.
While stomach enzymes and brine extracts have been used for centuries to curdle milk and separate whey from curds, today chymosin (vegetable rennet) is also used. Chymosin attacks only one milk protein at one point that allows the casein particles to bond to each other and form a continuous solid gel, or elastic curd.
A host of microbes construct and deconstruct cheese. For example, lactic acid bacteria acidify milk and create much of the curds' flavor during ripening — especially in semi-hard cheeses such as cheddar, Colby, Edam and Gouda and hardened cheeses such as Asiago, Parmesan and Romano. Propionibacteria are responsible for the holes in Swiss cheese. Smear bacteria contribute pronounced odors in cheeses such as Gruyère, Muenster and Limburger. (They also grow at salt concentrations that restrict other microbes.) When cheeses such as these are wiped with salt solutions they develop their orange exteriors. And molds with powerful protein- and fat-digesting enzymes, especially penicillium, help to improve the texture and flavor of cheeses (consider the French cheese St. Nectaire). Blue molds help create cheeses such as Roquefort, Stilton and Gorgonzola, while white molds are responsible for Camembert, Brie and Neufchatel.
In cheese production, either dry salt is added or cheese is brined in a sodium solution.
- blocks pathogens, controls starter cultures
- helps secondary flora bacteria in ripening
- regulates enzymatic activity during ripening
- affects texture such as hard, runny or stringy, functional properties such as melting or congealing, syneresis (the sudden release of moisture from protein molecules) and moisture (wetness or dryness)
- influences taste and flavor characteristics, and
- contributes to shelf life.
Process cheeses — generally uniformly smooth, shelf-stable (processing helps retard aging) and designed for mass-market consumption — are produced from natural cheeses and cheese by-products with added ingredients such as emulsifiers, stabilizers, food colorings and flavor enhancers like salt, sugar, vegetable oils or whey. Manufacturers may use mixtures of sodium citrate, sodium phosphate and sodium polyphosphates with new, partly ripened or fully ripened cheese to create process cheese, resulting in varying sodium content. One slice of American cheese has about 263 milligrams of sodium.
Cheese analogues (or cheese alternatives) imitate dairy cheese and often have different melting points, tastes, textures, sodium content and other characteristics than dairy cheese. The sodium content of one slice of soy "cheese" is about 180 milligrams.
Reduced-sodium cheese, like other reduced-sodium products that carry the U.S. Food and Drug Administration food labeling, must contain 25 percent less sodium than an appropriate reference food commonly consumed (RACC). A low-sodium cheese must contain 140 milligrams or less per serving per RACC.
Reducing sodium in cheese production is challenging, particularly in artisanal and specialty cheeses such as aged cheddar, blue, bloomy rind and curd. While different formulations have been investigated, such as using potassium chloride and other mineral salt replacers, sea salt, umami, yeast extracts, whey permeate and other cultures, coagulants and enzymes, there are both advantages and shortcomings for using ingredients other than sodium in cheese production. Food safety, quality, functionality and flavor may each be affected.
Yet, progress has been made.
The salt content of commodity mozzarella has been reduced to meet USDA specifications, and reduced-sodium process cheese and blended cheese for commodity purchase by schools have both been formulated.
Sodium plays a critical role in cheese production and a small amount of quality cheese can add lots of flavor, making foods such as vegetables and whole grains more desirable. Rather than eliminate cheese or turn to reduced-sodium cheese to lower daily sodium intake, have great-tasting cheese with plenty of whole grains and fresh fruits and vegetables. This way, you can have your cheese and be charmed, too.
Jacqueline B. Marcus, MS, RDN, LDN, CNS, FADA, FAND, is a consultant based in Highland Park, Ill., and author of Culinary Nutrition: The Science and Practice of Healthy Cooking (Elsevier 2014).
Savory Sun-dried Tomato and Asiago Biscotti
Recipe by Abigail J. Dougherty
1 cup all-purpose flour
1 cup white whole-wheat flour
3/4 cup cornmeal
1/2 teaspoon baking soda
1 1/2 teaspoon baking powder
1/2 teaspoon garlic powder
1/2 teaspoon salt
1/4 teaspoon pepper
1/4 cup smoked sun-dried tomatoes, coarsely chopped
3/4 cup Asiago cheese, finely grated, plus more for sprinkling
1/2 cup low-fat buttermilk
2 whole eggs, lightly whipped
2 tablespoons butter, melted
- Preheat oven to 375°F. Line a large baking sheet with parchment paper.
- In a large bowl, whisk flour, corn meal, baking soda, baking powder, garlic powder, salt and pepper until combined. Add sun-dried tomatoes and cheese to the flour mixture and stir until just combined.
- In a separate small bowl, combine buttermilk, eggs and melted butter. Pour buttermilk mixture into flour mixture and stir until sticky and just combined.
- Separate dough into two equal portions. Working with one section at a time, transfer dough onto parchment paper and mold dough into 10×3-inch rectangle. Flatten slightly to 1-inch height.
- Bake at 375°F for 25 minutes or until toothpick poked in the center comes out clean. Let cool for one hour.
- After biscotti have cooled, preheat oven to 325°F. Using a serrated knife, cut loaves into .- to .-inch slices.
- Replace each slice (cut side down) onto ungreased baking sheet and bake at 325°F for 12 minutes.
- Turn slices over and sprinkle with about 1⁄2 teaspoon of cheese per slice (if desired). Bake for additional 15 minutes.
- Transfer biscotti to wire racks to cool.
Serves 18 to 20
Serving Size: 1 biscotti
Calories 100; Total fat 3g; Sat. Fat 1g; Chol. 25mg; Sodium 188mg; Carb. 15g; Fiber 1g; Sugars 1g; Protein 4g; Potassium 82mg; Phosphorus 82mg
Abigail J. Dougherty, RDN, LD/N, is based in Tampa, Fla. She is a Stone Soup blogger and the author of TheSoulOfHealth.com.
White Beans with Parmesan-Cranberry Rice and Sage
Recipe by Tram Le
Olive oil cooking spray
2 tablespoons extra-virgin olive oil
2 tablespoons unsalted butter
3 cloves garlic, minced
1 tablespoon shallot, minced finely
3 tablespoons sage, chiffonade
1 15-ounce can white beans, drained and rinsed
1/4 cup dried cranberries
4 cups brown basmati rice, cooked
Zest and juice of 1 lemon
1/3 cup chicken broth
1/4 cup Parmesan cheese, grated
1/4 teaspoon kosher salt
1/4 teaspoon black pepper
1/3 cup panko breadcrumbs
1 tablespoon Parmesan cheese, grated
1 tablespoon sage, chiffonade
Olive oil cooking spray
- Preheat oven to 400°F. In an 8-inch saute pan over medium heat, heat the olive oil and butter for 2 minutes until bubbly. Add the garlic, shallot and 3 tablespoons sage; saute for 1 minute.
- Add the beans and stir to coat the beans with the olive oil mixture. Pour the mixture into a large bowl.
- Add the dried cranberries, brown basmati rice, lemon zest and juice, chicken broth, 1/4 cup Parmesan cheese, salt and pepper. Stir to combine and pour into 8 x 8-inch baking pan, coated with cooking spray.
- In a small bowl, stir together the panko breadcrumbs, 1 tablespoon Parmesan, and 1 tablespoon sage.
- Top the rice mixture with the breadcrumb mixture and spray evenly with olive oil spray.
- Bake in the middle rack of the oven for 15 minutes, or until lightly golden. Serve warm.
Serving Size: 1 cup
Calories 365; Total fat 11g; Sat. Fat 4g; Chol. 14mg; Sodium 240mg; Carb. 56g; Fiber 7g; Sugars 4g; Protein 11g; Potassium 411mg; Phosphorus 245mg
Tram Le, MS, RD, is based in Annapolis, Md. She is a Stone Soup blogger and author of This Veg Life.