How to Make Skyr Yogurt
How to Make Skyr Yogurt at Home: Authentic Icelandic Style Guide
The Short Answer
To make skyr at home, heat 1 litre of skimmed or low fat milk to 82 to 90°C, cool to 42°C, then stir in your live skyr starter culture. Incubate at 42°C for 10 to 12 hours until a firm curd forms. Strain through muslin cloth in the fridge for 8 to 12 hours to achieve the characteristic dense, almost dry texture that makes skyr noticeably different from Greek yogurt. The result is very high in protein and exceptionally thick.
In This Guide
Skyr has been a staple of Icelandic food culture for over a thousand years. It sits somewhere between a very thick yogurt and a fresh cheese in terms of texture, and it is one of the highest protein dairy foods you can make at home. Despite its dense, almost dry consistency, skyr has a surprisingly mild, clean flavour that is noticeably less tangy than Greek yogurt.
Making skyr at home is a longer process than other yogurt styles, primarily because it requires an extended incubation of 10 to 12 hours and a much longer straining time. But the result, a thick, protein dense fermented dairy product with a unique texture, is well worth the patience involved.
What is Skyr and How is it Different from Greek Yogurt
The Milk
Traditional skyr is made from skimmed or low fat milk rather than whole milk. This is what gives it an extremely high protein to calorie ratio. The fat content is naturally very low, making it one of the leanest high protein dairy foods available.
The Texture
Skyr is much denser than Greek yogurt. It is strained for significantly longer, typically 8 to 12 hours rather than 2 to 6, producing a texture that is almost dry and spoon standing. A spoon placed in authentic skyr should stand upright without sinking.
The Flavour
Skyr has a milder, cleaner flavour than Greek yogurt. The tang is present but gentle, with a slightly milky freshness that makes it very versatile as a base for both sweet and savoury dishes.
The Protein
Because skyr is made from skimmed milk and strained heavily, the protein concentration is very high compared to other yogurt styles. A 100g serving of skyr typically contains around 10 to 12g of protein, significantly more than standard yogurt.
What You Need to Make Skyr
Equipment and Ingredients
- 1 litre of skimmed or semi skimmed milk, for authentic low fat high protein skyr. Whole milk works and produces a creamier result but reduces the protein density
- Skyr starter culture, either our freeze dried skyr culture for a first batch or 1 tablespoon of your previous batch for reculturing
- A food thermometer, essential for accuracy at each temperature stage
- A heavy bottomed saucepan
- A clean glass jar or ceramic bowl, for incubation
- A yogurt maker, instant pot or warm oven, to maintain incubation temperature
- Muslin cloth or a fine mesh strainer, for the extended straining phase
- A large bowl, to catch the whey during straining
NutriBrew Tip: Skyr requires more patience than Greek or Bulgarian yogurt. The longer incubation and extended straining time are not optional. Rushing either stage will produce a thinner, less authentic result. Plan ahead and start your batch the evening before to strain overnight in the fridge.
Temperature Guide: What Makes Skyr Different to Ferment
Skyr uses a similar temperature profile to Greek yogurt but with a higher scald temperature and a significantly longer incubation. Here is what happens at each stage and why each one matters.
Scald at 82 to 90°C
Skyr requires a higher scald temperature than other yogurts. Heating to at least 82°C and ideally up to 90°C creates a stronger protein bond that can withstand the heavy straining required for authentic skyr without the curd collapsing.
Cool to 42°C, Add Culture
Allow the milk to cool to 42°C before stirring in the starter culture. Stir for 1 to 2 minutes to ensure even distribution. Never add the culture above 45°C as this will kill the live bacteria.
Incubate at 42°C for 10 to 12 Hours
Skyr bacteria are slower than standard yogurt cultures. A longer incubation of 10 to 12 hours is needed to allow the pH to drop sufficiently and produce a firm, cuttable curd. Do not disturb the yogurt during this time.
Optional Temperature Drop
After 3 hours at 42°C, you can optionally drop the temperature to 35°C for the remaining incubation time. This produces a milder, less acidic skyr. If you prefer a more pronounced tang, keep at 42°C for the full period.
Step by Step: How to Make Skyr
The Full Method
Step 1: Heat the milk
Pour 1 litre of skimmed or semi skimmed milk into a heavy bottomed saucepan. Heat slowly over a medium heat, stirring occasionally to prevent scorching. Bring to between 82 and 90°C. The higher end of this range produces a stronger curd that strains better.
Step 2: Cool to 42°C
Remove from heat and allow to cool to 42°C. You can place the saucepan in a bowl of cold water and stir to speed this up. Check with your thermometer and do not add the culture until the temperature is at or below 42°C.
Step 3: Add your starter culture
Stir in your skyr starter culture gently for 1 to 2 minutes until fully dispersed. If using a freeze dried culture, follow the packet instructions for quantity. If reculturing, use 1 tablespoon of your previous batch per litre of milk.
Step 4: Incubate at 42°C for 10 to 12 hours
Pour the inoculated milk into your incubation vessel and maintain at 42°C for 10 to 12 hours. Do not stir or move the vessel during this time. The curd needs an undisturbed environment to form properly. The yogurt is ready when it is firm and slightly resistant when you tilt the jar, and a small amount of whey may be visible around the edges.
Step 5: Rest at room temperature
Once incubation is complete, allow the yogurt to sit at room temperature for 2 hours before moving to the fridge or straining. This allows the protein structure to stabilise and reduces the risk of the curd breaking down during straining.
Step 6: Strain in the fridge for 8 to 12 hours
Line a fine mesh strainer with muslin cloth and place over a large bowl. Pour in the set yogurt, cover and refrigerate for 8 to 12 hours. The longer you strain the denser the skyr becomes. See the straining section below for full details.
How to Strain Skyr: Getting the Right Texture
Straining is where skyr becomes skyr. The extended straining time removes significantly more whey than Greek yogurt straining, producing the characteristic dense, almost dry texture that traditional skyr is known for.
4 Hours Straining
Produces a very thick, creamy yogurt similar to a rich Greek yogurt. Good texture for eating with fruit or granola but not yet the dense skyr consistency.
8 Hours Straining
Produces authentic skyr texture. Dense, almost dry, a spoon placed in the surface will stand upright. This is the traditional consistency and what most people associate with Icelandic skyr.
12 Hours or Overnight
Produces a very firm, cheese-like consistency. Excellent spread on toast or crackers, used as a cream cheese substitute, or blended with herbs for a dip. Extremely high protein concentration.
Do not throw away the whey. Skyr produces a large amount of whey during straining due to the extended strain time. This whey is rich in protein, probiotics and B vitamins. Use it in smoothies, bread making, soups, marinades or as a liquid for cooking grains. It keeps in the fridge for up to 1 week.
How to Recultue Skyr
Like all our yogurt cultures, skyr can be reused indefinitely by saving a small amount of each batch to start the next.
Reculturing Rules
How much to use: 1 tablespoon of your previous batch per 1 litre of new milk.
Important: Save your reculturing portion before straining, from the freshly set yogurt rather than the strained skyr. Straining removes moisture and concentrates the culture, which can affect consistency when used as a starter.
Freshness window: Use yogurt no more than 7 days old. Beyond this the bacterial strains weaken and the yogurt will become progressively thinner over successive batches.
Backup: Every 4 to 5 batches, freeze a small amount of freshly set skyr before straining as a backup. If a batch fails you can restart from frozen without purchasing a new culture.
Skyr Troubleshooting
Skyr is Too Thin After Straining
Cause: Milk not heated high enough or straining time too short
Fix: Scald to at least 85 to 90°C and strain for a full 8 to 12 hours in the fridge. Using whole milk instead of skimmed also produces a slightly less firm curd.
Curd Broke Down During Straining
Cause: Yogurt moved to the fridge too quickly after incubation
Fix: Always allow the set yogurt to rest at room temperature for 2 hours before refrigerating or straining. This stabilises the protein structure.
Yogurt Did Not Set After 12 Hours
Cause: Culture killed by heat, incubation too cool, or culture past its best
Fix: Always confirm temperature with a thermometer before adding the culture. Skyr needs a consistent 42°C for the full incubation period.
Skyr Tastes Too Sour
Cause: Incubated for too long at high temperature
Fix: Drop the temperature to 35°C after 3 hours and finish incubation at the lower temperature. This produces a noticeably milder result.
Grainy or Lumpy Texture
Cause: Milk heated too fast, culture added too hot, or yogurt disturbed during incubation
Fix: Heat milk slowly, confirm temperature before adding culture, and do not move or stir during incubation.
Getting Thinner Over Batches
Cause: Reculturing from strained skyr or from yogurt older than 7 days
Fix: Always save the reculturing portion before straining and use yogurt no older than 7 days. Start fresh from a frozen backup if the culture has weakened.
Frequently Asked Questions About Making Skyr
Is skyr the same as Greek yogurt?
No, though they are similar in that both are strained dairy products with a thick texture. Skyr is traditionally made from skimmed milk and strained for much longer, producing a denser, higher protein result with a milder flavour. Greek yogurt is made from whole milk, strained for a shorter time and has a richer, creamier texture with a more pronounced tang. Our Greek yogurt guide covers the full comparison.
Can I make skyr with whole milk?
Yes. Whole milk produces a creamier, richer skyr with a slightly less firm texture after straining. If you want the traditional lean, very high protein skyr that Iceland is known for, skimmed or semi skimmed milk is the right choice. Whole milk skyr is closer in character to a very thick, strained Greek yogurt and is equally delicious, just different in nutritional profile.
Why does skyr need such a long incubation compared to other yogurts?
The specific bacterial strains in skyr work more slowly than those in standard yogurt cultures. A full 10 to 12 hours is needed to allow the pH to drop sufficiently and produce a firm, cuttable curd that can withstand the extended straining process. Shorter incubation produces a softer set that breaks down during straining and results in a thin, disappointing texture.
How long does homemade skyr last in the fridge?
Homemade skyr stored in a sealed container will keep well for up to 2 weeks in the fridge. Because of its high acidity and low moisture content after straining, it is actually quite shelf stable compared to other fresh dairy products. Always use a clean spoon when serving to avoid introducing contamination.
What can I use skyr for besides eating it plain?
Skyr is extremely versatile. Use it in smoothies as a high protein base, as a substitute for cream cheese on toast or in dips, blended with herbs as a savoury spread, in baking as a substitute for buttermilk or sour cream, or layered with fruit and granola. Overnight strained skyr has a consistency very close to cream cheese and works well in any recipe that calls for it.
Explore More Yogurt Cultures
From classic Greek and Bulgarian to Scandinavian Viili and Finnish Piima, we have a culture for every taste.