Why Is My Homemade Yogurt Slimy? Causes, Fixes, and Prevention
Sneak Preview: Find out the cause of your slimy yogurt, how to avoid it in the future, whether it’s safe to eat, and more.
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The first time I made slimy yogurt, I was shocked. I expected creamy, spoonable goodness but got a stringy mess instead. Determined to figure out what went wrong, I went into full investigation mode.
There was no way I could share that batch—it would’ve ruined my yogurt-making reputation! So I dug deep to find the cause and, more importantly, how to prevent it. If you’ve run into the same problem, keep reading—I’ve got answers! Because homemade food should be food worth sharing.
Shared & Loved
“Thanks for the great site. I came here because I made my usual yogurt with 1 liter of UTH milk plus 1/2 cup of milk powder. Came out stringy and slimy, but the taste is fine. Now I understand why.”
–KM
What Causes Slimy Yogurt?
If your homemade yogurt has a stringy or slimy texture, the most likely cause is wild yeast contamination.
- Wild yeast is airborne and can disrupt the bacterial balance in your yogurt.
- Using a starter from a slimy batch will continue to produce the same undesirable texture.
- Heirloom starters are more resistant to wild yeast than store-bought yogurt starters.
Choosing the Right Yogurt Starter
The type of yogurt starter you use plays a major role in preventing slimy yogurt. There are two main types:
- Grocery Store Yogurt as a Starter
- Typically contains only a few strains of bacteria, making it more vulnerable to wild yeast.
- Over time, these strains weaken and may produce inconsistent results.
- Best practice: Refresh with a new container of yogurt every 3-4 batches to maintain stability.
- Traditional or Heirloom Yogurt Starters
- Contain a diverse blend of bacteria that make them more resilient.
- Designed to be reused indefinitely with proper maintenance.
- Less likely to be affected by wild yeast, making them a more reliable option.
“The difference with a traditional starter is that it is composed of more varied bacteria so that when one strain falls prey to phages (a virus that infects and replicates within bacteria), there will be others to take over and maintain fermentation.”Sandor Ellix Katz from The Art of Fermentation(paid link)
How to Prevent Slimy Yogurt
- Start with a reliable yogurt starter – Traditional starters are best for preventing contamination.
- Use a fresh starter – Avoid reusing a starter from a slimy batch.
- Avoid cross-contamination – Some recommend avoiding baking yeast bread the same day you make yogurt. (I do this weekly but it has never caused a problem since I started using a traditional starter.)
- Refresh your starter every 3-4 batches – Store-bought yogurt weakens over time as a starter.
- Keep utensils clean – Wash all equipment thoroughly to reduce contamination risks. I don’t think it’s necessary to sterilize all of your equipment. See the quote below.
“But generally sterilization is unnecessary. Incidental microorganisms that inevitably are found in non-sterile though clean environments cannot generally gain a foothold in a fermentation substrate. This is because the ferment either has its own indigenous microbiota (as in sauerkraut and traditional wines), or has had a critical mass of cultures introduced (as in yogurt, tempeh, and most contemporary beers). We are living in a microbial world, and these processes all developed under decidedly non-sterile conditions.
Traditional mixed culture starters tend to be stable under favorable conditions. Only in the realm of propagating pure-culture mold spores, which tend to pick up more bacterial strains with each successive generation, have I found sanitization beyond mere cleanliness to be warranted.”
Sandor Ellix Katz from The Art of Fermentation(paid link)
Is Slimy Yogurt Safe to Eat?
- Generally, yes, if it smells fine and has no mold.
- The texture will be different, and the taste may be slightly yeasty.
- If it has an off smell, discard it.
Can Slimy Yogurt Be Fixed?
- No, once yogurt turns slimy, there’s no way to reverse it.
- Do not strain it—this will only worsen the texture.
- Do not use it as a starter for a new batch.
What to Do with Stringy Yogurt
If you don’t want to eat it as is, consider using it in:
- Smoothies
- Baking (as a substitute for buttermilk)
- Cooking (soups, marinades, or dressings)
Viili Yogurt: The Exception
Viili is a Finnish yogurt variety that is naturally ropey and stringy. If you enjoy the texture, you might want to try making Viili intentionally.
Frequently Asked Questions
- Why does my yogurt have a slimy texture?
- Wild yeast contamination or using a starter from a previous slimy batch.
- How do I prevent my yogurt from turning stringy?
- Switch to a traditional starter, keep your equipment clean, and replace store-bought starters every few batches.
- Can I use slimy yogurt as a starter?
- No, a slimy starter will produce more slimy yogurt. Always start with fresh yogurt.
For more yogurt-making tips, check out this “Question and Answer” guide to making thicker, creamier homemade yogurt!
Final Takeaway
- Your yogurt starter matters! Traditional starters are more resilient and resistant to contamination, making them the best choice for long-term yogurt-making.
- If you use grocery store yogurt as a starter, refresh it often. The bacterial strains weaken over time, making contamination more likely.
- Slimy yogurt is usually caused by wild yeast. Keeping equipment clean and limiting exposure to airborne yeast can help prevent it.
- Once yogurt turns slimy, it can’t be fixed. Start fresh with a new, uncontaminated starter for the best results.
Questions? Email me: Paula at saladinajar.com. Hope to see you again soon!
Paula Rhodes, owner
As a retired home economist, I created Saladinajar.com to share my belief that you don’t have to be a chef to find joy in creating homemade food worth sharing. Bread machines (used in an unconventional way), homemade yogurt, and quick microwave recipes are my specialty.