Process Cheese

[Photo courtesy of Kraft Foods]

When I was in first grade, I went through a cerebral cheese period. My cousin Michael got me started because he brought a jar of Cheez Whiz to school in his lunch box every day. Naturally, I was jealous, but I was also curious. What was pasteurized process cheese sauce?

He would spread it on crackers, his sandwich, or dip a celery stick into it.I used to daydream about bringing Cheez Whiz to school for lunch—but, alas, it never happened. Yet other questions later arose: What was cheese food? Cheese spread? Cheese product? Imitation cheese? How were they different from just plain old American cheese? Anyhow, I forgot about it.

With this past holiday season, however, I had a renewed interest in cheese. I began to dig up some cheese factoids. Cheese is perhaps the oldest processed food known to mankind and one of the most ubiquitous foodstuffs in the world. In 1910, the average American ate 5 lb of cheese per year, but that had grown to 28 lb per year by 1998. Process cheeses, around for more than 50 years, have had a great impact on this growth spurt. I witnessed plenty of big cheeses during the holidays who had a cheese ball in the fridge, set out slices of American cheese for sandwiches, or served melted Cheez Whiz or Velveeta mixed with salsa as queso dip for nachos during college football bowl games.

To determine the difference between all the types of process cheese, I thought I could just phone Northfield, Ill.-based Kraft Foods —makers of Cheez Whiz and Velveeta—and find out all I wanted to know. However, a spokeswoman had to cheese it on providing any information for proprietary reasons. So I ended up on the Internet plowing through Title 21 Part 133 of the U.S. Code of Federal Regulations, which governs cheeses, and I contacted Dairy Management Inc. , a Rosemont, Ill., firm responsible for increasing demand for dairy products on behalf of U.S. dairy farmers.

Beginning with the basics, cheese is a concentrated dairy food made from milk. A starter culture of bacteria is first added to convert some lactose—the primary milk sugar—to lactic acid. An enzyme, commonly chymosin, is next added to coagulate casein—the major milk protein—into a soft solid, or curd, that consists of calcium caseinate and milkfat. Milkfat exists as globules of a triglyceride wrapped in a phospholipid-protein membrane.

The remaining liquid—the whey, which contains soluble proteins and lactose—is next removed to leave the fresh cheese. The curd is then stirred and heated, salt is added or the curd may be treated with brine, and the cheese is pressed into molds. For ripened cheeses, the curd is further treated with select strains of bacteria, mold, or yeast that generate enzymes that can hydrolyze fats, proteins, and lactose. These biochemical changes modify the cheese's flavor and texture as it ages.

Two criteria used by the Food & Drug Administration to define cheeses and set forth in the Code of Federal Regulations are moisture content and milkfat content. Cheddar, for example, is allowed a maximum moisture content of 39% and must contain at least 50% milkfat. Cream cheese, on the other hand, is an unripened cheese that can have a maximum moisture content of 55% and must have at least 33% milkfat.

There are a number of different types of process cheese specified by FDA, and because the federal regulations stipulate that the type of cheese must be indicated on the package label, many people have been left scratching their heads wondering exactly what they are buying and consuming.

Pasteurized process cheese, for example, is made from one or more cheeses, such as cheddar or colby, and may have cream or anhydrous milkfat added. The cheese is blended and heated with an emulsifier—typically a sodium or potassium phosphate, tartrate, or citrate—and other optional ingredients such as water, salt, artificial color, and spices or other flavorings.

The cheese is then poured into molds to solidify and is later packaged. This processing produces a smooth, mild-tasting cheese that melts easily. For pasteurized process cheese, the final product can have a maximum moisture content of 43% and must have at least 47% milkfat. An interesting twist is that the product alternatively can be labeled as pasteurized process American cheese when made from cheddar, colby, cheese curd, granular cheese, or a combination of these; when other varieties of cheese are included, it must be called simply American cheese.

Here are some of the other definitions:

 Pasteurized process cheese food is a variation of process cheese that may have dry milk, whey solids, or anhydrous milkfat added, which reduces the amount of cheese in the finished product. It must contain at least 51% of the cheese ingredient by weight, have a moisture content less than 44%, and have at least 23% milkfat.

 Pasteurized process cheese spread is a variation on cheese food that may contain a sweetener and a stabilizing agent, such as the polysaccharide xanthan gum or the Irish moss colloid carrageenan, to prevent separation of the ingredients. The cheese must be spreadable at 70 F, contain 44 to 60% moisture, and have at least 20% milkfat.

 Pasteurized process cheese product is process cheese that doesn't meet the moisture and/or milkfat standards.

 Imitation cheese is made from vegetable oil; it is less expensive, but also has less flavor and doesn't melt well.

For the record, Velveeta is pasteurized process cheese spread and Velveeta Light is pasteurized process cheese product. Cheez Whiz is labeled as pasteurized process cheese sauce, although that type isn't noted in the Code of Federal Regulations. A Kraft spokeswoman confirms that the word "sauce" just seems to be an add-on.

This array of information has brought me full circle on my cheesy odyssey that began in first grade. It has left me pondering about where we would be today without process cheese products such as Cheez Whiz or Velveeta to put on top of a burrito or on top of broccoli or cauliflower—all "dangerously cheesy" stuff, as my own first-grader now says.

Steve Ritter

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