Why we are excited about Skyr Yoghurt

Symbiota are the proud cultivators of a true delight – an Icelandic probiotic culture that dates right back to the uber-strong Norse Vikings. Maybe this yoghurt is the powerhouse of the strength and determination behind the success of Viking warriors? Let’s find out.

What is Skyr Yoghurt, and what does it taste like?

Skyr is a traditional Icelandic dairy culture that is used to make cheese and yoghurt. It has been a cornerstone of the Viking diet since the arrival of dairy animals around the 9th century. 

Traditionally, skyr is made by fermenting milk, then concentrating the yoghurt consistency by straining away the whey. The result is a thick, spoonable and satisfying yoghurt, one that is often classified as more like a soft cheese. Modern explanations from Iceland describe the texture and taste of skyr as smooth, mildly tangy and creamy, with a decadent, spoonable texture.

What types of Icelandic cultures are in Skyr Yoghurt?

Skyr is unusual among Nordic fermented milks because it requires more heat that is easily available in the cooler climates. Often the traditional ferments of cooler Nordic countries favoured mesophilic yoghurts, which can ferment milk into yoghurt at simple room temperatures (such as Viili yoghurt and Caspian Sea yoghurt). In contrast, Skyr is made from a warm‑loving, thermophilic, yoghurt culture that requires heat to make a complete yoghurt. Studies that have examined traditional skyr cultures have found a small but consistent cast of probiotic microbes:

• Streptococcus thermophilus

• Lactobacillus delbrueckii bulgaricus

• Lactobacillus helveticus

In some cultures, lactose‑fermenting yeasts have also been found in the skyr culture starter samples. Modern research into the effects and health benefits of skyr have found that these yoghurt culture strains are supportive players in well-known probiotic health effects such as modulating the immune system, influencing healthy cholesterol levels, and helping the body to digest milk proteins more effectively.

What is the protein content of Skyr Yoghurt?

Historically, skyr was highly valued as a nutrient‑dense staple food in Iceland. Investigations by multiple modern researchers have consistently demonstrated that the fermentation probiotics of Skyr are remarkably effective at amplifying the protein content of dairy milks. 

In practical terms, the traditional straining process method of removing whey from skyr curd to gain thickness is the primary method of increasing the protein density of the final skyr yoghurt. In modern production methods, equipment such as quark separators or ultrafiltration units does the same job at scale. This concentration step brings the dry matter measurements of skyr yoghurt into the 20–25% range, a notably higher in protein density than comparative unstrained yoghurts. This generally equates to an average protein content range of 9-12%, depending on the ingredients used:

• Traditional: 11-12g protein per 100g
• Low Fat:   9-10g protein per 100g
• Flavoured (diluted):   8-10g protein per 100g

Because skim milk is often used to make skyr, the final product is both low in fat and high in protein per spoonful. This is one reason why skyr has become more popular for those interested in high‑protein, probiotic-rich yoghurts.

How does Skyr Yoghurt compare to Greek Yoghurt, and Regular Yoghurt?

Greek yoghurt and skyr are close European cousins. Both yoghurts are thick, high‑protein dairy ferments that are culturally associated with regions – Greek yoghurt with the Mediterranean, Skyr with the Nordic countries. 

There are some key similarities and differences between Skry, Greek and Regular yoghurts that we have drawn together from both research and consumers. Average ranges are given as that typically found in a plain, unsweetened variety of the yoghurt type:

How do you make Skyr Yoghurt at home?

For home fermenters, our Symbiota Skyr Yogurt Starter Culture give a clear and easy method to follow at home. The Symbiota method follows the same basic pattern described in traditional and modern skyr production – heat, culture, warm ferment, then thicken.

1. Heat the milk.

Start by heating milk to 100° C, then allow to cool to 43° C. This high heat step echoes the older practice of boiling milk for skyr, and the cool‑down makes sure the starter culture is not damaged.

2. Add the Skyr starter.

Once the milk temperature is between 40–43° C, stir in the Symbiota Skyr Yoghurt Starter Culture thoroughly. In traditional kitchens with simple Icelandic provisions, this step was done by back‑slopping from a previous batch. With Symbiota starters, you can use either a fresh starter which replicates the back-slopping traditional practice, or you can use a dried starter for convenient applications.

3. Incubate and keep warm until thick.

Keep the temperature of the cultured milk between 40–43° C and leave it to ferment for 5–24 hours, depending on your setup and desired tang. During this warm hold, the thermophilic cultures (such as Streptococcus thermophilus and Lactobacillus delbrueckii bulgaricus) get to work, thickening and acidifying the milk. If you see small curds forming during this stage, that is completely normal and a great sign that fermentation is occurring successfully.

4. Chill, then strain.

Once the milk has clearly thickened, chill the new skyr in the fridge for a few hours to set. For a very dense, traditional texture that is high in protein, strain the skyr through a cheesecloth or nut‑milk bag for 3–5 hours (ideally in the fridge). Allow the whey to drain away to leave a thick, creamy skyr yoghurt in the fabric.

*Rennet can also be used if you prefer more defined curds and whey, and this echoes the older descriptions of traditional skyr making.

5. Bottle and chill.

Transfer the strained skyr into clean jars and seal with a lid, then keep cool in the fridge until serving.

6. Repeat.

To keep the skyr culture going indefinitely, simply save a portion of the finished skyr and use it as the starter for the next batch. One tablespoon of skyr will culture one cup of fresh milk, and will provide you with a continuous, heirloom‑style supply of skyr. You’re a modern Viking now!

What types of milk can be used to make Skyr Yoghurt?

Historically, skyr began as a method to preserve milk from the sheep that Viking settlers brought back to Iceland hundreds of years ago. As the skills for farming animals shifted with advances in human knowledge, cow milk became widely available and produced a greater volume of food. Skyr made from cow milk is now the standard for modern skyr production both in Iceland and abroad.