Thoughts from the Farm: Acid
Hey there local food eaters,
Do you think about and taste for acid when you cook?
Do you think and taste when you cook at all, or just follow a recipe?
Today I'm continuing to share what I've learned from the great non-recipe cookbook Salt Fat Acid Heat, and we’re talking about ACID.
Acid, the author Samin Nosrat expounds upon, is a balancing flavor. "Acid grants the palate relief, and makes food more appealing by offering contrast." Think cranberry sauce with a heavy thanksgiving meal. Or lemon sherbet in between courses at a fancy restaurant (do they still do that?). A big green salad with lots of vinegar to finish off a Sunday supper.
She tells a story of making carrot soup at Chez Panisse and being told by the chef to, "Add a capful of vinegar to the pot before you bring it up!" "Vinegar? Who'd ever heard of putting vinegar in soup? Was [the chef] crazy? Did I hear him right? I didn't want to ruin the entire pot, so I took a spoonful of my beautiful soup and added a single drop of red wine vinegar. Tasting it, I was floored. I'd expected the vinegar to turn the soup into a sweet-and-sour abomination. Instead, the vinegar acted like a prism, revealing the soup's nuanced flavors -I could taste the butter and oil, the onions and stock, even the sugar and minerals within the carrots. If blindfolded and quizzed, never in a million years would I have been able to identify vinegar as one of the ingredients. But now, if something I cooked and seasoned ever tasted so dull again, I'd know exactly what was missing."
I have a theory that a lot of obsessive hot sauce users are really after the acidic flavor, not just the spice. We have a friend who puts Frank's Red Hot, or Sriracha on everything, to the point that it's annoying. I've said to him before, "Can you please taste the food how it is before dumping hot sauce all over it?" It is an easy way to make a taste explosion in your mouth without attention to detail.
There are other ways. Samin shows in drawing form the preferred tart flavors around the world:
She explains, "The term mouthwatering has long been a synonym for delicious. Foods that are the most enjoyable to eat [literally] cause our mouths to water - that is to produce saliva. Of the five basic tastes, acid makes our mouths water the most. When we eat anything sour, our mouths flood with saliva to balance out the acidity, as it's dangerous for our teeth. The more acidic the food, the more saliva rushes in. Acid, then, is an integral part of many of our most pleasurable eating experiences." Pleasurable, and probably healthful too. Lots of folks these days start eating sauerkraut or kimchi for health reasons, because they are touted as probiotic, digestion- enhancing foods. And they are, for a myriad of reasons. They also taste good, and can be addicting. Once you get used to a bit of fermented vegetables with a meal, it doesn't taste or feel right to go without, in my opinion.
A handful of things I've learned about cooking with acid:
Just as cooking with fats, the type of acid influences the direction of a dish, so let geography and tradition assist you in choosing type of acid. "A peanut butter sandwich, for example suffers without the tang jelly provides. No proper Brit would consider eating a plate of fish and chips without malt vinegar. Imagine carnitas tacos without a spoonful of salsa". Maybe this concept is why the willy nilly hot sauce use is slightly offensive to me; and perhaps my extravagant use of sauerkraut would be to someone else!
Acid and vegetable COLOR: acid dulls vibrant greens, so wait until the last possible moment to dress salads or squeeze lemon on to cooked green vegetables like asparagus. However, acid preserves the vibrancy of reds and purples such as cabbage, red chard stems, or beets; they benefit from being cooked in a slightly acidic medium. Raw fruits and vegetables such as sliced apples, bananas, or avocados retain their natural color better if coated in water with a few drops of lemon juice.
Acid and vegetable TEXTURE: "Acid keeps vegetables and legumes tougher, longer. When cooking vegetables in a soup, stew, or just in water, wait to add vinegar or other acidic seasoning till after they are soft. Add tomatoes at the end.
Acid and proteins: Acid tenderizes initially (denaturation), but then toughens (coagulates) proteins. With eggs, "a few secret drops of lemon juice will produce creamier, more tender scrambled eggs. For perfect poached eggs, add a capful of vinegar into boiling water to hel pspeed up coagulation of the white and strenthen the outer texture, while preserving the runny yolk." With fish, don't marinate for more than a few minutes, unless you are making ceviche; lemon juice as a garnish is perfect though. With meat, acid helps break down collagen, which is tough structural component. "Add wine or tomatoes as you begin to cook braises and stews, since the more quickly the collagen melts, the sooner the meat will grow juicy and succulent."
Salt, time, and tradition can produce acid by way of fermentation. Our favorite foods: beer, wine, sourdough bread, cheese, pickles, cured meats, coffee, chocolate, etc. are preserved largely through the chemistry of acidity. These ingredients can also be used in dishes as sources of balancing acidic flavor.
Layer acid use, by using both "cooking acids" from the start (i.e. tomatoes for sauce, cooking vinegar in a braise) as well as garnishing or seasoning acids to serve (i.e. a final squeeze of lemon, or dash of balsamic vinegar).
Learn and practice the trick of quick-marinated onions. Soaking sliced onions in vinegar for even a few minutes mellows their bite, making raw onions so easy to eat even little kids love them; when Terra was three, she would sit with the near empty salad bowl, eating all of the vinegary onions saying, "I LOVE onions!"
Use acid to balance the dish, as well as the meal. Light and sour salads balance out rich, meat based meals, and the acid and fiber may aid digestion also.
"Play to each element's strengths: use Salt to enhance, Fat to carry, and Acid to balance flavor. Now, with the knowledge of how they affect various foods, add each to a dish at the right time in order to season it from within. Add salt early to a pot of beans, but acid late. Season meat for a braise in advance, then start it off on the heat with a dose of cooking acid. When it's done and rich in flavor, lighten it with a garnishing acid."
Thanks for the cooking lesson, Samin!