While many people enjoy yogurt fresh from culturing, you might find you want to improve the texture and consistency of your homemade yogurt by thickening it.

When to Thicken Yogurt

Using Re-Usable Starter Cultures

If you're making yogurt using an heirloom starter culture that requires activation, it's not uncommon for the activation batch to be somewhat liquidy and thin.

This is perfectly normal, as the bacteria in the freeze-dried cultures are just starting to wake up and get active during the first batch. While you may want to jump for a thickener or groan out of disappointment, the milk is still cultured and can be used to culture future batches.

 

It's during these next few batches that the texture and consistency should even out. If you'd still prefer a thicker yogurt after a few batches, then consider using one of the methods below to thicken your yogurt.

Keep in mind that thickening agents can sometimes interfere with re-culturing, so keep some extra starter yogurt on hand if you plan to experiment with different thickeners.

Using a Vegan Yogurt Starter Culture

On the other hand, if you are making yogurt using a Vegan Yogurt Starter Culture, which is a direct-set (or single-use) culture, you'll want to add a thickening agent to help it set. Several of the thickening agents below need to be added to milk before heating and culturing, so be sure to pick out a thickener before getting started. The Vegan Yogurt Starter Kit comes with a thickening agent to help you get the perfect texture.

METHODS FOR THICKENING YOGURT

1. Adjust Your Starter or Milk

Depending on the type of milk used and the culture chosen, yogurt can be as thin as buttermilk or as thick as sour cream. Choosing a different type of milk for making yogurt, or selecting a yogurt starter with different properties are two ways to increase thickness of the final product.

2. Increase the Fat Content

The fat in yogurt is part of what makes it thick, so using whole milk will result in a thicker yogurt than skim milk.

You can also add cream to the milk or use it in place of milk to increase the fat content. Heavy cream is too low in lactose to sustain an heirloom culture long-term, so be sure to refresh the starter in whole or 2% milk after 2-4 batches if you decide to use this.

3. Heat the Milk Longer

When preparing the milk, heat it to 160º-180°F, and maintain the temperature for 20 to 30 minutes. Then cool to culturing temperature.

(If milk is accidentally heated to over 180°F, simply let it cool back to 180°F before maintaining the temperature.)

Heating the milk denatures the proteins, allowing them to form a stronger network when exposed to acid (like lactic acid produced by the bacteria in yogurt cultures). Thus, a higher temperature, held for a longer time, will give you a firmer yogurt.

It's important to heat the milk slowly to make a creamy yogurt. Heating the milk too quickly will create a grainy texture.

4. Strain the Yogurt

Our Greek Yogurt Maker, a cotton bag or tight-weave cloth, or a piece of butter muslin are all effective tools to use for draining whey from yogurt. Doing so removes some of the water, leaving the fats and proteins behind. The longer you drain whey, the thicker your yogurt will become. (Don't toss that whey either - there are lots of ways to use whey!)

5. Add Thickeners!

This is a process that is most successful with direct-set cultures, or when maintaining a separate mother culture, since the thickeners may interfere with re-culturing. Yogurt usually will not thicken until cooled, especially non-dairy yogurt. In some cases, thickening can take up to 24 hours. Even if the yogurt is thin, it is still a cultured food and may be consumed (it's great for whipping up smoothies!)

Yogurt Thickeners

Milk Solids

Powdered milk solids generally come in cow, goat, and soy varieties.

When to Add: Add to milk before heating and culturing.

Instructions: For every 3-4 cups fresh cow milk use ½-1 cup powdered milk. If using fresh goat milk or soy milk add ¼-½ cup powdered milk.

Pros: Does not require additional heating or additives. Does not introduce other ingredients.

Cons: Powdered milk is processed, which you may be choosing to avoid. This thickener is not suitable for raw yogurt.

Gelatin

When to Add: Add to milk before heating and culturing.

Instructions: For every 3-4 cups milk, sprinkle 1 tablespoon of gelatin into 1 cup of cold milk. Gelatin must be heated to at least 95⁰F to activate. Mix well to combine. For yogurts cultured at room temperature, be sure to allow the milk to cool to the culturing temperature before adding starter culture.

Pros: Can achieve very thick, commercial-style texture. Neutral taste.  Suitable for raw milk yogurt as it doesn’t need to be heated beyond the raw threshold.

Cons: Not suitable for vegetarians or vegans.

Pectin

When to Add: Prepare thickener in milk before heating and culturing.

Instructions: When making 1 quart of yogurt, pour 2 cups of milk into a blender. Add 1-2 teaspoons pectin (depending on the type of pectin), and blend until pectin is incorporated. Add to the rest of the milk and heat to 140⁰F. Cool to culturing temperature and add culture.

Keep in Mind: The quantity of pectin may need adjusting depending on the milk or pectin used. Sugar-activated pectin may require additional sugar in the milk to be effective. Calcium-activated pectin uses the calcium in the milk to set up. When using non-dairy milks, add the amount of calcium water specified by the recipe.

Pros: Best choice for vegan yogurts. Consistent results. Gives texture similar to gelatin and can be very thick.

Cons: Pomona’s is not available in all grocery stores (but you can find it here or in the Vegan Yogurt Starter Kit). Not suitable for those with a citrus allergy. Standard (sugar-set) pectin has a large impact on the flavor of the yogurt and requires large amounts of sugar. Not suitable for making raw yogurt.

Agar

When to Add: Add to milk before heating and culturing.

Instructions: For every 3-4 cups milk, dissolve ½ teaspoon powdered agar into the milk. Heat to 190⁰F and hold for 10 minutes. Cool to culturing temperature and add culture.

Pros: Low allergen and good vegan option.

Cons: Texture may be inconsistent. Requires longer heating period to work properly. Not suitable for making raw yogurt.

Guar Gum

When to Add: Add to milk before culturing or to yogurt after it's cultured.

Instructions: For every 3-4 cups milk, add 1 teaspoon guar gum to cold milk before heating and culturing. (You can also add it to milk after heating, but milk should be cooled first.) Or, add 1 teaspoon guar gum per 3-4 cups of cultured yogurt.

Pros: Can be added after the yogurt is cultured. Does not require heating to work, so it is suitable for making raw yogurt.

Cons: Texture is not as smooth as other methods. Requires thorough blending to avoid lumps.

Tapioca Starch

When to Add: Add to milk before heating and culturing.

Instructions: For 3-4 cups of milk, dissolve 2 tablespoons tapioca starch into the milk and heat to 140⁰F. Cool to culturing temperature and add culture.

Pros: Easier to find than some products. Good option for vegans.

Cons: Can be very inconsistent. If overheated, it will fail, but it must reach at least 140⁰F to work.

Arrowroot Starch

When to Add: Add to milk before heating and culturing.

Instructions: For 3-4 cups of non-dairy milk, dissolve 1½-2 tablespoons of arrowroot starch into the milk and heat to 140⁰F. Cool to culturing temperature and add culture.

Pros: Good option for non-dairy milks.

Cons: Not recommended for use with dairy milks.

Ultra-Gel (modified corn starch)

When to Add: Add to cooled milk after heating milk and before culturing.

While regular corn starch can be used, it is not particularly stable and can yield an odd consistency.

Instructions: For 3-4 cups milk, add ¼ cup Ultra-gel to the milk after is has been heated and cooled. Mix well to combine.

Pros: Does not appear to require heat to work. Easy to find. Gives consistent results.

Cons: Highly processed. Not available in a GMO-free option.

What Not to Do

It may be tempting to add more cultures to the yogurt in an attempt to increase the probiotic content, but this is rarely successful.

Yogurt cultures are carefully balanced so that the strains work together to give a particular result in terms of taste and consistency. Adding additional strains can weaken or even kill off the yogurt cultures, and may even produce something that is harmful to eat.

So, when working with yogurt starter cultures, try one of the methods above to thicken your homemade yogurt to your liking.