Fizzy drinks are controversial, but I have always adored sipping on something extremely bubbly-back to my four-cans-of-diet-coke-a-day days (read: years). I’m very thankful that kombuchas and seltzers are having a moment!
Enter: Sima. This light, tart, fizzy fermented lemonade is traditionally served on May Day in Finland. Apparently it typically accompanies tippaleipä, a funnel cake. Sounds like a lovely way to usher in spring! Personally, I find this fermented lemonade delicious year-round, and it’s quickly becoming a staple in my home. The yeast, which gives sima it’s fizz, also gives it a signature tang.

Benefits of fermentation
Most likely, you’ve heard a lot about the importance of including fermented foods in your diet. Fermented foods can support your gut microbiome by supporting your good bacteria and introducing more strains. Fermentation can also increase the bioavailability of the nutrients in your food, meaning you can actually access and use more of these nutrients. Foods can be fermented in a few different ways-some foods rely on wild yeasts and bacteria out of the air, while some, like this fermented lemonade, have the yeast added directly during preparation. I love fermented foods and include several in my family’s diet. Sima has been a welcome addition to our fermentation repertoire- especially since it’s so kid friendly.
What you’ll need
As home ferments go, sima is uncomplicated to make and requires relatively little by way of equipment. It’s a great option for those who are just learning to make ferments due to it’s simplicity, but those who are more seasoned will want to give this a shot too-it’s too good to pass up! You will want:
- Large pot
- large non-metallic container- I use a glass gallon jar
- cutting board & knife
- Bottles-I use these
- Funnel
Ingredients for Finnish fermented lemonade
- Lemons
- Sugar: both white and brown
- Raisins
- Water
- Active dry yeast

How to make sima
Wash and thinly slice lemons, and set aside.
Bring water to a boil on the stove. When it reaches a boil, add brown sugar, 1 cup white sugar, and lemons and stir. Remove from heat and allow to cool to lukewarm.
Transfer to a non-metallic container (I use this jar). Add yeast when lemonade is between 110-115 degrees. If you don’t have a thermometer, it should feel only very slightly warm to the touch. Cover lightly.
Leave to sit on the counter until little bubbles begin to appear at the upper edge, approximately 8-10 hours or overnight.
Sterilize your bottles. I do this by pouring boiling water over clean bottles in the sink, then using an oven mitt to carefully transfer them to a clean area on the counter.
Place granulated sugar in each bottle- I use about 1 teaspoon each, but you can adjust to taste and to the size of your bottles, about 1-2 teaspoons per quart of sima. Place a few raisins in each bottle as well.
Strain the sima and pour into your containers. Cork or seal tightly.
Let stand at room temperature until the raisins have risen to the top of the sima. The time this takes will vary depending on the temperature of your kitchen, from 8 hours to 24 or more. When the raisins have risen, the sima is ready to drink.
Place in the refrigerator. This will both chill your sima and stop further fermentation. Enjoy!

Sima-Finnish Fermented Lemonade

Delightfully fizzy, tangy home-fermented lemonade
Ingredients
- 1 gallon filtered water
- 1 cup brown sugar
- 1 cup + 2-3 Tbsp granulated sugar
- 2-4 lemons
- 1/8 tsp active dry yeast
- about 1 Tbsp raisins
Instructions
- Wash and thinly slice lemons
- In a large pot, bring water to a boil
- Add brown sugar and 1 cup granulated sugar. Add lemons and remove from heat
- Allow to cool to lukewarm (110-115 degrees Farenheit).
- Add yeast. Transfer mixture to a non-metal container such as a large glass jar
- Cover lightly and leave to sit overnight at room temperature (or until little bubbles appear near the surface of the sima)
- Sterilize bottles and place granulated sugar in each; about 1-2 tsp per quart of water or to taste.
- Place a few raisins in each bottle
- Strain sima into bottles and cover tightly
- Leave to sit at room temperature until all raisins have risen to the top of the sima. This could take anywhere from 8-24+ hours depending on the temperature of the kitchen
- Transfer to fridge to chill and stop fermentation. Serve chilled.
Notes
1. The number of lemons you choose to include will alter the tartness quite a bit. With 2 lemons the sima will be crisp and tangy, but quite sweet. With 4 it will be very tart and not really sweet at all. I love it with 4, but it is neither kid nor husband friendly that way, at least in my house!
2. Once corked and fermenting on the counter, you will want to burp sima once a day. I typically burp my bottles once after about 12 hours fermentation time, let them sit on the counter another 12 hours or so, at which point the raisins are generally all risen. If you do not burp them at all the sima will be fizzier, but you run the risk of bottles exploding or a cork flying off. The first time I attempted sima, I left my bottles too long and when I tried to uncork them, the whole cork and clasp went shooting off into the sink, followed by most of the liquid. I'm thankful that I had the good sense to aim the bottle away from my kids.
3. To burp, I hold the cork down, flip the clasp up until I hear the carbon dioxide whooshing out. I only let out the first spurt of excess air before firmly re-corking. If you like a less fizzy sima, you can let out more air.
Do I have you excited to get some lemonade fermenting on your counter? Questions about the process? Let me know in the comments! Maybe coming soon: a version made from grapefruit…sounds seasonally appropriate and delicious.
Hi Carol,
I’m super excited to try this sima!!! My family and I love fermented fizzy drinks so this might be a big hit in my house. I’ve been neglecting my kombucha lately so this will be a good alternative. I have a question, do you think I can use some of my starter tea from my kombucha instead of yeast? Thanks!
Yes, there’s plenty of sugar in the sima for it to eat so it should work fine! My understanding is that a SCOBY prefers tea, but if it is strong it will ferment a non tea liquid too! Please let me know if you try it that way, I’d love to hear how it works.