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Liz Thorpe knows her cheese. When the vice president of New York's Murray's Cheese Shop and author of The Cheese Chronicles isn't helping high-end restaurants select the right fromage for their dessert menus, she's traveling around the country taste-testing products herself. Thorpe has tried every type of cheese: the creamy, the crumbly, the limp, the spongy and even something flavored with Jamaican jerk spices. TIME talked to Thorpe about unpasteurized cheese, how Swiss got those holes and how white and yellow cheddar differ.

How did you become so interested in cheese?

I'd always liked eating cheese. I moved to New York City after college and the food-shopping experience was unlike anything I had ever encountered. My neighborhood had a lot of old, southern-Italian food vendors and there was one shop that had a cheese counter. There were 30 different options of cheese, but they didn't look or taste anything alike. It was very baffling and exciting to me.

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You mention in the book that although there are hundreds of different cheeses, there are only a handful of basic recipes. How do we get so many varieties?

There are about a dozen steps in the basic process of turning milk into cheese. All cheeses go through some combination of those steps, but any tiny variation in any one of them will create a different texture and flavor. The first step in cheese making is called acidification  the process of converting the sugar in milk into acid. You do that by putting starter bacteria in your milk. There are hundreds of different bacteria that work at different speeds to produce different cheeses. You could have 500 or 1,000 variations on just that one step. There's something very exciting and mysterious about it that's almost like magic.

What's the difference between white cheddar and yellow cheddar?

Yellow cheddar has had a natural plant-based coloring added to it called annatto, which comes from a South American plant. It doesn't affect the flavor or texture. It's not a chemical. People's preference for white versus yellow is mostly cultural. Wisconsin is yellow cheddar territory. Vermont is white cheddar. We have some shops out in Ohio, and the idea of selling white cheddar there is crazy. But there is no intrinsic difference.

Why does Swiss cheese have holes in it?

As the cheese ripens, there is a bacteria inside it that breaks down the protein. It stretches the cheese and makes holes. The number and size of the holes has to do with how much bacteria is in the cheese, how active it is, and the temperature of the room that the cheese is aged in.

In the 1990s, people discovered goat cheese. In the early 2000s, high-end restaurants started offering cheese plates. What do you see as the next big cheese trend?

Cheese is something people are much more interested in and knowledgeable about than they were 20 years ago. But people are still pretty limited. They know Swiss, cheddar, goat cheese, blue cheese, brie  and that's about it. But they keep learning. It's like what happened with wine. Fifty years ago, Americans didn't drink any wine. Then they discovered European wines. Then people started trying to make wine in California. Now people know American wine and European wine and they're starting to learn about grapes, like the difference between Merlot and pinot grigio. I think that will happen with cheese. I also think we'll see a lot more American-made cheeses from specific producers. That, to me, is the next big wave. We finally discovered wine, but cheese is about 20 years behind.

What is raw-milk cheese and why are people afraid of it?

Raw milk means unpasteurized. By law, raw-milk cheese must be aged for at least 60 days because it kills all the bad bacteria in the unpasteurized milk that might make people sick. After 60 days, it's safe. Raw-milk cheese has more vitamins and is better for you, but if you don't know about the 60-day rule you may think it's dangerous to eat. People want to be safe and they don't want to get sick. They know there's a law but they don't know what the law is. Eventually they'll learn.

Is there anything in Cheez Whiz or powdered cheese that is actually cheese?

No, none of that is cheese. It's primarily made out of vegetable oil. Real cheese is made out of three things: milk, salt and some sort of coagulant, which will be listed either as enzymes or rennet on the label. You can add flavoring such as dill or pepper or nuts. Aside from that, cheese has three ingredients and only three ingredients.

If someone came to you with only a basic knowledge of cheese and they wanted to try something new, what would you suggest?

I think I would start with a variation of a cheese they have some familiarity with. I'd suggest an aged, clothbound cheddar. This is basically cheddar that is made in a traditional English style, in a big 30- to 50-lb. wheel, not in a block. The wheel is wrapped in cheesecloth and sealed with melted lard or some sort of oil. It's aged in a room on a wood shelf for nine to 14 months. The flavor development is totally different from cheddar that you would, say, grate on an omelet. It's drier, more crumbly and the flavor is nutty. It has a lot of caramelized toffee flavors to it. It's not sharp. People love it.