Spring has sprung and that means one thing: It's time for pickles. Whether on a burger, within a taco or atop a salad, pickles give any dish great added texture and that vinegary bite that can easily become habit-forming. However, what is it that vinegar actually does to turn fresh fruit and vegetables into the sweet-savory-sour pickles that we love? Here's a look at the science behind vinegar pickles.
First, a disclaimer: There are two distinct methods for pickling in this world. The one discussed below ensures preservation by immersing produce into an acidic solution (i.e. vinegar), like dill pickles and Mexican escabeche. The other, much older method is fermentation caused by a chemical reaction between naturally present bacteria and a food's sugars, like kimchi. While we are solely focusing on the first method in this case, you can find a more in-depth explanation of the latter here.
The Ingredients
Vinegar pickling (or quick pickling) is a simple process. Water, salt and vinegar (and sometimes sugar) are combined and heated and then fruit or vegetables are immersed in that liquid. However, there is a lot of variation within those ingredients that needs to be taken into account.
According to Eugenia Bone, author of Well-Preserved: Recipes and Techniques for Putting Up Small Batches of Seasonal Foods, the most important thing about vinegar is its five percent acidity, which causes changes in flavor and texture and acts as a preservative. In terms of which vinegar to use, it depends on the desired taste and color of your pickles. Distilled white vinegar and white wine vinegar are most popular because they won't affect the color of most vegetables (red onions, however, will turn bright pink when exposed to white vinegar). The other common option is cider vinegar, which offers a milder flavor, but causes the produce to darken.
Next, there's the question of salt. According to Bone, the best salts to use for pickling are pickling (or canning) salt or kosher salt. Pickling salt is pure granulated salt and is free of anti-caking agents, which can cause the pickling liquid to turn cloudy. Kosher salt, however, has large crystals, which do not dissolve as quickly as pickling salt. Either salt is fine, but kosher salt will take more effort to use.
The water you use to pickle can also make a big difference. According to Bone, hard water, which is rich in minerals, and heavily chlorinated water can both interfere with the pickling process. But if you're comfortable drinking the water, it's probably fine for your pickling project.
The Process
There's one more defining thing about vinegar pickling: It involves no fermentation. In addition, vinegar pickled foods lose much of their nutritional value over time. Nonetheless, they stay quite delicious for quite a while.
Vinegar-based pickling is a much faster process than fermentation pickling. In its quickest form, you'll just boil a vinegar solution, pour it over the the object of your pickling desire, let it all cool and stash it in the fridge.
But for maximum preservation power, you'll want to do this: Brine the vegetables (to add crispiness and flavor), then drain them, then boil them in a vinegar solution. Package the vegetables and liquid into jars, cover them in the remaining hot vinegar solution and can them.
Either way, the vinegar's acetic acid will increase the the vegetables' acidity and kill off any existing microorganisms, which will help prevent prevent short-term spoilage.
The Science
Pickling is a sort of controlled decay, according to according to Dr. Bruno Xavier, a food processing authority at Cornell University. "When living organisms die, they activate several responses in the tissue that trigger the release of enzymes," says Xavier, that start to break down the vegetable. The acid from the vinegar, along with naturally forming acids in the food itself, slows down that decaying process. "There are certain salts," Xavier adds, "especially those containing calcium, that will help preserve some of the crunchiness of the pickle." You'll find those salts in commercial pickles.
And that's why you can pickle green beans in June and enjoy them in October. If you're inclined to give this a shot yourself, here's some pickling inspiration.
FAQs
The main principle of pickling is to add an acid such as vinegar or lemon juice to reduce the pH to low acid foods. The pH range is usually below 4.6. Acid foods include such as tomatoes – green ones work better, all hard vegetables – such as zucchini, onions, cucumbers, cauliflowers, eggplant and so on.
What is the principle behind pickling using vinegar? ›
The main principle of pickling is to add an acid such as vinegar or lemon juice to reduce the pH to low acid foods. The pH range is usually below 4.6. Acid foods include such as tomatoes – green ones work better, all hard vegetables – such as zucchini, onions, cucumbers, cauliflowers, eggplant and so on.
How does pickling work scientifically? ›
In chemical pickling, the food is placed in an edible liquid that inhibits or kills bacteria and other microorganisms. Typical pickling agents include brine (high in salt), vinegar, alcohol, and vegetable oil, especially olive oil but also many other oils can be alternatively used (Lee, 2004).
What is the chemistry behind pickles? ›
As lactic acid bacteria grow in your pickle crock, they digest sugars in the cucumbers and produce lactic acid. Not only does this acid give the pickles their characteristic sour tang, it controls the spread of spoilage microbes.
Why does vinegar help preserve things like pickles? ›
Vinegar is an acidic substance that functions as a preservative. Vinegar is a strong acid (acetic acid), and when used for pickling, it lowers the pH of preserved foods. Because just a few germs can thrive in a low pH environment, vinegar aids in preservation.
Why do you have to boil vinegar for pickling? ›
You take all of your ingredients, apart from the product that is being pickled, and bring them to a boil. The heating process helps activate the flavors in the brine and marry them together. This hot brine is then poured over what is to be pickled and then stored in the refrigerator.
What is the best concentration of vinegar for pickling? ›
Picklers should look for a pickling vinegar with 5% acetic acid concentration or higher. This is to ensure your vinegar is acidic enough to prevent the growth of bacteria and mould in your pickle jars. The more acidic the vinegar, the longer your pickles will last.
What is the biological concept of pickling? ›
Pickling is the process of preserving edible products in an acid solution, usually vinegar, or in salt solution (brine). In the latter case, the acid that does the preservative action (lactic acid mainly) is produced by fermentation. The process of pickling is also known as brining and the resulting foods as pickles.
What is the theory of pickling? ›
The “Pickles' Theory of Relativity” talks about the ratio between Salt, Sugar Vinegar and Water in creating the perfect pickling liquid. In this case the ratio is 1:3. First, apply the 1:3 ratio to vinegar and water- 1 cup of vinegar to 3 cups of warm water.
Can you pickle with just vinegar? ›
Vinegar-based pickles are the most common form of pickling. Cut vegetables are submerged in just boiled vinegar brine. This process destroys the natural culture and rich enzymes. The acidic nature of denatured vinegar does the preserving.
Quick pickling is simply the act of storing fresh produce in a brine of vinegar, salt, water, and sometimes sugar, in the refrigerator. These pickles are not canned and are ready to eat mere hours after making, though I usually wait at least a day or two.
What's the difference between fermentation and pickling? ›
An easy way to remember the difference between the two despite their overlap is that pickling involves putting food into an acidic brine to produce a sour flavor, whereas fermenting gives food a sour flavor without any added acid.
Can bacteria grow in pickle brine? ›
Most bacteria cannot grow well in acid fluids like pickle juice. So its the combination of salt and acid.
What is the principle of pickling? ›
Pickles are preserved by a combination of increased acidity (reduced pH), added salt, reduced moisture and added spices. Pickles can be prepared using one of two main methods: lactic acid fermentation of vegetables, either with or without the addition of salt the preservation of vegetables in acetic acid (vinegar).
Should I add water to pickling vinegar? ›
You'll need vinegar, water, kosher salt and sugar for a basic brine. (Don't use iodized salt for your pickles, as it could make the brine cloudy and change the color and texture of the vegetables.) The basic ratio for quick pickles is 1:1 vinegar to water, and includes some combination of salt and sugar.
Do real pickles use vinegar? ›
Pickling preserves food in a solution of vinegar, salt, and sometimes sugar. This acidic environment prevents the growth of bacteria, making the pickled food safe to eat and extending its shelf life.
What is the principal of pickling? ›
The pickling process involves placing produce in a salt brine solution which draws moisture out through osmosis. Lactic acid bacteria in the produce ferment in the brine, producing lactic acid which preserves the food. Proper salt concentration and temperature are needed for fermentation.
What is the principle of vinegar? ›
Vinegar can be made from any carbohydrate source, amylaceous, or sugary substrate through two successive fermentations: alcoholic fermentation, which is carried out by means of yeasts, and acetic fermentation, with acetic bacteria as the protagonist.
How is pickling vinegar different than regular vinegar? ›
Vinegar used for pickling must at least 5% acidity. Look at the label to be sure that the vinegar you are using is 5% acidity. Sometimes vinegar will be labeled as grain; 5% acidity is the same as 50 grain. Most white and cider vinegars used for making pickles and salsa are 5% acidity, but not all.
What is the principle ingredient in vinegar? ›
Vinegar is an acid with its key ingredient, acetic acid. It is widely used for food preservation and cooking. The acetic concentration for table vinegar is typically 5% whereas higher concentration upto 18% is used as preservative. The word "vinegar" is derived from vin aigre, meaning "sour wine".
