Correction to This Article
The Food 101 column in the Feb. 15 Food section misidentified the French farmer who revived the production of Epoisses de Bourgogne cheese. He was Robert Berthaut of Bourgogne, not Philippe Olivier. Olivier is a well-known cheesemonger in Boulogne-sur-Mer.

Soft on Cheese

By Robert L. Wolke
Wednesday, February 15, 2006

Two of my favorite French cheeses are Epoisses and Bucheron, the latter from goat's milk, the former from cow's milk. When I buy it, the Epoisses varies from a soft texture similar to that of brie to a thick syrup that flows as soon as the rind is pierced. And the Bucheron, even when refrigerated, slowly becomes softer and softer, eventually turning into a sharp-tasting, yellow-green, viscous liquid. What processes are taking place in these cheeses?

According to Jonathan Swift, "He was a bold man that first eat an oyster." You must be an even bolder one to put up with a slimy green liquid.

Cheeses are unquestionably among gastronomy's most sparkling gems. But the cold, hard fact is that the aging of cheeses is in reality nothing but controlled spoilage. What happens as cheeses age is what happens to any food in which bacteria and molds are allowed to have their way.

Epoisses de Bourgogne is a rare cheese produced exclusively by one stubborn farmer named Philippe Olivier in Boulogne-sur-Mer. Once a popular cheese, the Epoisses was rescued by Monsieur Olivier when it began to die out in the 1940s, and perhaps for good reason. I quote from : "Epoisses Frais, which is 30 days old, is firm, moist and grainy with a fresh acidity and mild yeasty tang. Forty days old cheese has orange-brown rind and is very sticky."

But what happens after still more time? If Olivier doesn't pasteurize his milk (as many French cheese makers do not), his cheese must be at least 60 days old to be legally imported into the United States. By then, it's probably on the verge of turning into the thick syrup you describe.

You get the drift: Cheese ripening is a slippery slope that can lead to slippery slop.

Both the Epoisses and the Bucheron are ripened by bacteria, and bacteria will continue doing their thing for as long as they are allowed. The chemistry of cheese ripening is complex, but mostly it involves decomposition of the cheese's protein (proteolysis) and fat (lipolysis). The protein breaks down into amino acids and eventually to ammonia, which has a pungent, unpleasant smell and is a clear signal of an overripe cheese, although some people enjoy a touch of ammonia in their Camembert. The fats break down into fatty acids, which have strong flavors. With exactly the right amounts of amino and fatty acids, the cheese is suitably mature. Much beyond that, and you're flirting with fate.

Moral: Make your cheesemonger sell all soft cheeses only at their peak of ripeness or slightly before. Then eat them promptly.

I'll be glad to help.

My daughter is currently deployed in the Persian Gulf, and I sent her some homemade English muffins and cookies recently. All arrived moldy and inedible. Are there any kinds of preservatives I can use in the future to prevent this?

There are some things neither of us has any control over, among them the length of time it takes to get a package to Iraq and the climate there.

Be that as it may, there are some things you can do -- not by adding chemical preservatives to your baked goods as commercial bakers do (the commercial preservatives would be hard to find anyway), but simply by packing your goods properly.

Molds need three things to grow: moisture, warmth and something to eat. You have generously provided these voracious fungi with something to eat. But with proper packaging, you can deprive them of the other two.

Let your muffins and cookies cool completely after they are baked. Until they're cool, they're giving off moisture, and if you wrap them too soon the mold spores -- which are in the air everywhere and cannot be avoided -- will have a field day. Moreover, you can take it for granted that your baked goods will be exposed to high humidity and warm temperatures as they approach their destination. If not well wrapped, the cookies -- especially soft cookies -- will absorb moisture from the air.

So before putting your baked goods in sealed plastic containers, wrap them individually and tightly in aluminum foil or waxed paper. That way, even if one or two start to get moldy, the spores won't spread to the others.

And you know those little white envelopes that come packed with new electronic equipment and other products, the ones that say "Do not eat" on them? (Why don't they stamp that gratuitous warning on the rest of the packing materials?) They contain silica gel, which absorbs moisture from the air and keeps the products dry. It wouldn't hurt to save a couple of them in a tightly closed jar and toss them into your package of goodies.

By the way, if wrapped individually, brownies will last almost forever. I have had an undeliverable package of brownies returned to me from Singapore, and they were received still fresh after I corrected the address and sent them back several weeks later.

LABELINGO: Perspicacious reader Stephen Zon of Severn sends the wrapper from a loaf of Whole Grain Flax bread from a company called The Baker. Its Nutrition Facts chart says that one slice provides 30 percent of the daily value for calcium. In smaller print, it admits that the bread is "not a significant source of . . . calcium."

Robert L. Wolke ( is professor emeritus of chemistry at the University of Pittsburgh. His latest book is "What Einstein Told His Cook 2, the Sequel: Further Adventures in Kitchen Science" (W.W. Norton, 2005). He can be reached

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