How is yogurt made

By playing with the variables at your disposal, you'll be able to dial into the style you like most. It's a personal journey toward the very best yogurt of your dreams.

These are the basic steps. The milk you use will have a huge impact on your final yogurt. Let's start by looking at the obvious variables, like fat percentage. They all work. You can also thicken your yogurt by adding a small amount of unflavored gelatin 1 teaspoon per quart of milk before scalding the milk in step four, below. You don't have to add either of these things, and I'd suggest starting out by not adding them, but it's something to play with over time as you seek your own house style.

Beyond fat percentage, there's the milk's origin and processing to consider. Most types work. You can use raw milk, if available, or pasteurized milk; grass-fed milk or milk from cows raised on feed; homogenized milk or creamline milk Homa of White Moustache recommends stirring the cream in only after the yogurt has been made for the best texture. The one kind of milk that routinely gets a bad rap is ultra-pasteurized milk, which most major organic brands are, as well as the UHT milks that are shelf-stable at room temperature when unopened.

I've managed in my tests to successfully make yogurt using ultra-pasteurized milk, but my limited success doesn't disprove the wisdom of more experienced yogurt makers that it's a more difficult kind of milk to work with. I'd avoid it. The starter is the set of bacterial cultures that will ferment the milk's natural lactose sugars into lactic acid, thickening the milk and souring it at the same time.

There are a million options. You can buy freeze-dried starter cultures, which look like powder, or you can use a plain store-bought yogurt with live active cultures.

Store-bought is easier, plus you get some extra yogurt out of it, but your options are limited to what's on supermarket shelves. Freeze-dried starter cultures come in wider varieties. I've had good experience with the products from Cultures for Health. They sell basic yogurt cultures, plus ones tailored for specific yogurt styles, like Greek and Bulgarian yogurt, as well as a handful of heirloom varieties. Some of the heirloom varieties they offer are mesophilic, meaning they do their work at room temperature as opposed to the more common thermophilic cultures used in most store-bought yogurt, which requires a warmer environment ; this can take longer and often produces a runnier yogurt than thermophilic cultures.

I had mixed success when attempting to make some of those mespohilic cultures during my testing, as you can see in the photo above, in which some of the samples separated into distinct layers of curd and whey.

For most people starting out, a good store-bought yogurt with live active cultures, such as Fage, will be easy to procure and will yield great results, but, once again, you're free to experiment and find what you like best. Of all the variables I tested, skipping the scalding step was one of the few that led to near-certain failure.

Scalding does a few important things. First, scalding the milk helps kill off any unwelcome microbes that may have found their way into it. The less your starter culture has to compete with, the better.

But this isn't the only reason to do it—otherwise ultra-pasteurized milk would be a lot more successful. That leads us to the single most important thing scalding does: It denatures the whey protein lactoglobulin. According to Harold McGee in On Food and Cooking , lactoglobulin, once denatured, gathers on the surface of the milk's casein proteins. This coating of lactoglobulin acts as a barrier, making it more difficult for the casein proteins to bind to each other in small, tight-knit groups, which would form a lumpy, broken curd, not the smooth one we expect of yogurt.

Instead, the caseins bond more loosely into an interconnected network that makes for a consistent, gelled mass. How long you scald the milk determines how much water in the milk is allowed to cook off, concentrating the milk proteins and fat and resulting in a thicker texture. This is another one of those levers you have at your disposal: scald the milk more briefly for a looser yogurt, or hold it at the higher temperature for upwards of 30 minutes to concentrate it.

Just be careful to scrape the bottom of the pot during this step, or you'll end up scorching the milk and infusing the yogurt with a burnt taste.

If you were to add your starter culture to the hot milk, you'd kill it and then you'd have no yogurt. So you need to let the milk cool down to a temperature zone in which the lactose-eating bacteria can survive and thrive.

Freeze-dried starter cultures can be stirred right into the milk. If using yogurt as your starter, it helps to thin it first with some of the warm milk so it can disperse evenly, then stir that into the pot. This is the big moment, when your liquid milk transforms into thick cultured yogurt.

To make it happen, you merely need to give the milk and bacteria the opportunity they need to do their thing. Throughout much of my testing, I obsessed with creating the most temperature-stable environment possible, worrying about fluctuations of even a couple degrees. You have more latitude than that—that, really, was Homa's point. This isn't to say the incubation temperature doesn't matter. It does, and it can affect the final yogurt, but it's more complicated than simply holding a single "perfect" temperature without variation.

Here's what happens during this phase: The lactose-eating bacteria produce lactic acid as a byproduct, which begins to sour the milk. As the pH drops and the milk grows more acidic, the milk proteins begin to bond and gel which the scalding step helped prep for.

How quickly the bacteria eat the milk sugars and produce lactic acid is connected to the temperature of the milk. How is yogurt made?

Is yogurt healthy? What kinds of bacteria are in yogurt? Yogurt earns its reputation as a healthy snack by being high in protein and minerals.

It's also a good food for people who are lactose intolerant, since it contains a special enzyme that breaks down lactose in the intestines. Since yogurt can be made in regular, low-fat, and non-fat varieties, you can choose a specific yogurt that meets your goals for daily fat intake. Wonder What's Next? Ask a friend or family member to help you check out the following fun activities: Do you like to go shopping for groceries with your family? Get out and get some yogurt today!

Take a field trip with an adult friend or family member to a local grocery store. Find the dairy aisle and check out their selection of yogurt. How many different flavors can you find? Which ones sound delicious to you?

If you can, get several different types of yogurt to take home and sample throughout the coming week. Do you like yogurt? Do you love fresh pineapple and raspberries? If so, then you're going to want to try out this yummy recipe for a Yogurt Parfait as soon as possible! Be sure to check the list of ingredients before you get started.

You might need to head to the store for a few supplies first. Feel free to substitute other fruits to make your own tasty treat, too! If you're up for a challenge, why not try to make your own homemade yogurt?

Jump online and read through the instructions to make Plain Homemade Yogurt. You'll need just a few simple supplies. Be sure to ask an adult for help along the way. Have fun making homemade yogurt for your entire family! Did you get it? Test your knowledge. Wonder Words milk sugar acid treat goat dairy flavor yogurt primary tangy texture creamy alternative bacteria ingredient fermentation consistency lactose Take the Wonder Word Challenge.

Join the Discussion. Noah Feb 12, Feb 6, What's up, Eniaya? How did you like this Wonder of the Day? Kevin McMurtrie Jun 7, Hello Wonderopolis, That wonder about yogurt is super-dee-duper! By varying the types of organisms in the cultures, yogurt is produced much faster and lasts longer than conventional yogurt. Additionally, the nutritional aspects of yogurt will be more thoroughly investigated There is some evidence that has shown consumption of yogurt has a beneficial antibiotic effect.

It has also been shown to reduce the incidence of lactose intolerance and other gastro-intestinal illnesses. Other purported benefits of yogurt include the reduction of cholesterol, protection against certain cancers, and even boosting the immune system. The research is still not complete on these benefits however, these factors will likely be important in the continued market growth of yogurt. Helferich, W. Yogurt: All About It, Hui, Y. Dairy Science and Technology Handbook.

Robinson, R. Edited by Gordon R. New York: Van Nostrand Reinhold, , pp. K and A. Edited by B. London: Elsevier Applied Science Publishers, , pp Toggle navigation. Made How Volume 4 Yogurt Yogurt. When the milk arrives at the plant, its composition is modified before it is used to make yogurt.

The milk substance is fermented until it becomes yogurt. Fruits and flavorings are added to the yogurt before packaging. Other articles you might like:. User Contributions: 1.

Obi Theodora. The article is quite educative. But i will like you to add references to the article and also I want to know what happens to yoghurt during storage. That is what happens to the fat content, total solids and total soluble solids. Can you recomend the best culture to be used as a starter to give a good taste of yogurt?

How can I prepare yogurt at home just for household consumption? I liked the article i think it was educational and i would like to know more. So how many products would be produced per day? I would real appreciate it if you answer my questions as soon as posssible. I want to prolong the shelf life of yogurt for their small sales. Is sodium benzoate added as a preservative? At any stage of production it can be added? How much is the recommended amount healthy?

I am waiting for your reply. Thank you.