Ruhlman's Twenty (13 page)

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Let the shallots cool, then peel them.

1
/Cooked macaroni is tossed with the soubise and placed into the baking dish.

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/Top with shredded cheese.

ACIDIC LIQUIDS HEIGHTEN FLAVOR.
If you’ve cooked any soups or stews, you’ve already put this critical lever beneath your food to lift it up. The ability to use salt well and the ability to cook foods to the right temperature—these are important skills to have, but are often discussed explicitly in recipes and directives to home cooks. Less often stated is the importance of using acid as a seasoning device. It’s second only to salt in its potential for elevating the flavors of your cooking.

The power of acid was the first of many “a-ha” moments I experienced in culinary school. We were making a cream soup (broccoli), but the point was to learn the creamed soup technique and about the last thing I would have thought to put in my lovingly tended soup was a shot of vinegar! Vinegar in cream? I approached Chef Pardus like Oliver approaching Mr. Bumble. He sat behind his desk, paper toque rising high above his brow, grade book and tasting spoons before him. I set the soup down. Pardus drew his spoon through the soup, lifted some with the spoon, and let it fall—evaluating consistency. Good. Then he tasted. He evaluated the seasoning. The soup had the right amount of salt, but something was missing. “I want you to take this back to your station and taste the soup. Then take a spoonful and put a drop of white wine vinegar in it. Taste it, and tell me what you think.”

I did as instructed. The spoonful with the drop of vinegar was markedly better, more complex, more interesting—
brighter.
Bright is an element of flavor that takes some imagination. I don’t mean literally brighter, but synesthetically brighter: vinegar has a brighter
flavor
—clear, clean, crisp. Some people I’ve encountered don’t “see” this. But put a drop of white wine vinegar in cream of broccoli soup and taste it. The name for the change in flavor is brightness.

The vinegar in cream soup was a great lesson in using acid to season food. All dishes should be evaluated in part for their level of acidity. It’s one of the five main taste sensations. Just about everything you make, from a cream soup that begins the meal to a butterscotch sauce that ends it, can be enhanced with acid. In my opinion, the two elements that make a really good butterscotch sauce are not the butter and the sugar, but the salt and the cider vinegar that make the butter and sugar come alive. In these instances, you don’t want to taste vinegar; if you can taste vinegar in a butterscotch sauce, it has too much. Just as you don’t want to taste the salt in a soup, you don’t want to taste the vinegar.

Evaluate your food and think about its acidity. Why do pickles go well on sandwiches? It’s not for the flavor of the pickle so much as for the pickle’s acidity, which makes the other ingredients taste better. Next time you make a sandwich, think about it, evaluate your sandwich, and ask yourself if a little acidity wouldn’t make it taste better. When you taste anything, ask yourself, What would make this better? Often the answer is acid.

Acid
is a generic term for anything acidic. You can add vinegar or lemon juice to what you’re cooking, and in the same way that you can add anchovies to a pot for their saltiness, you can add, say, sauerkraut to a dish that needs a little acidity. Following are the main categories of acidic ingredients you can use to give your food contrast and brightness.

• Vinegars (Red, white, sherry, and cider are all valuable.)
  
• Citrus juices (lemon juice, lime juice) or other fruit juices (verjus, which is the juice from unripe wine grapes, or cranberry juice)
  
• Pickled fruits and vegetables (from cucumbers to capers to kimchi)
  
• Sour fruits (tamarind, sour cherries, green tomatoes)
  
• Wines (Use only those you would drink; don’t buy “cooking” wine.)
  
• Mustards
  
• Sour leafy greens (such as sorrel) or sour vegetables (such as rhubarb)
  
• Cultured dairy preparations (such as yogurt, sour cream, or goat cheese)
  

A few forms of acidity deserve special attention.

The first, by a good mile or so, is lemon juice. Lemon juice is one of the most valuable seasoning tools in the kitchen. More foods than not are elevated with the addition of lemon juice. Always have a lemon on hand. Salt, onion, lemon— a kitchen without these items is handicapped.

The second most important acid is vinegar. What’s important here is not so much the kind of wine vinegar you use (white, red, or sherry) but the quality. The better your vinegar, the more influential its impact on your food. The larger the proportion of vinegar relative to the rest of the ingredients, the more important that quality is. A vinaigrette is almost wholly dependent on the quality of the vinegar.

You usually get what you pay for. A very cheap vinegar tastes that way. The best vinegars are delicious, not simply harshly acidic. Buy a good sherry vinegar from Spain and taste it— think about the flavor. In my opinion, a sherry vinegar is the most versatile, and good-quality sherry vinegars are widely available. From a seasoning standpoint, wine vinegars are largely interchangeable. You would use a white wine vinegar when a red wine vinegar would alter the color of a dish, but, again, the quality of the wine vinegar is more important than the type of wine it was made from.

Be wary of gimmicky vinegars, those infused with herbs and fruits. I’m not saying they’re necessarily bad—just be aware that their claims may be specious. That herbs de Provence vinegar may be delicious, but think about it. If you want herbs in your food, why not put them in yourself? What is the point of a raspberry vinegar? Think about it for a minute. If the taste suits you, terrific, but flavored vinegars like this have limited uses. Better to spend your money on a quality red or sherry vinegar.

Balsamic vinegar is in its own category. This special Italian elixir prized for its flavor and the balance of acidity and sweetness is sometimes so good that it’s taken straight as a digestif. Think of balsamic vinegar more as a finishing flavor, in the category of a condiment, rather than an all-purpose seasoning.

Other components that bring acidity to a dish are pickled vegetables and mustards. Swirl a little mustard into a gravy, and that gravy becomes more interesting and complex. Sprinkle pickled chiles on braised meats such as short ribs or pot roast.

Of course, sauerkraut goes great on a corned beef sandwich, but you could also chop sauerraut and stir it into the
Winter Vegetable Garbure
for an interesting acidic counterpoint to the fresh cabbage and smoky bacon flavor.

Acidity can also be the main feature of a dish. In North Carolina, pulled pork is mixed with a vinegar-based sauce and called barbecue. This delicious contrast to the rich, unctuous slow-cooked pork shoulder should not be confused with the tomato-based sweet-sour barbecue sauces that go into pulled pork in the western part of the state, or, farther west and south, the tomato-based sauces mixed with grilled/ barbecued or smoke-roasted brisket for barbecue in Texas. All barbecue sauces include a healthy dose of vinegar.

A fish preparation called ceviche uses acid to “cook” fish. The fish is marinated in lemon or lime juice along with other aromatic ingredients and eaten at room temperature.

Acid can help preserve food by debilitating microbes that cause spoilage. Pickles are one common example. Another is an ancient preparation, now referred to as escabèche (es-keh-BEHSH), in which cooked fish gets a bath in a warm acidic sauce.

Acid is a fundamental ingredient in some cheese making. Added to warm or hot milk, acid will cause the milk solids to group together and congeal into curds that can then be pressed and aged into cheese.

But here, we are concerned with the impact acidity has on food generally, acidity as it relates to seasoning. Having an authoritative control over the acidity level of everything you prepare is one of the most important skills to develop as a cook.