Keto Strawberry Lemonade
Published August 1, 2020 • Updated March 15, 2026
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I cook fresh strawberries down and strain them into a concentrated juice for this sugar free strawberry lemonade. The result is bright, tart, and actually tastes like real lemonade, not sweetener water with a berry tint.
Most keto strawberry lemonade recipes just blend raw berries with water and sweetener. I’ve made enough of those to know they all taste the same: flat, diluted, vaguely pink. So I built this recipe around a different approach. You cook the strawberries first, then strain out every bit of pulp and seed. What’s left is a deep ruby concentrate that carries real strawberry flavor into the finished drink.
That cook-and-strain step is the whole reason this works. Raw blended berries add color but not much else. Cooking draws out the natural sugars and acids, and straining gives you a clean, smooth juice you can mix straight into lemonade without any grittiness or pulp floating around. I pair it with freshly squeezed lemon juice, cold water, confectioners Swerve, and two pinches of salt.
The salt matters more than you’d think. I made a batch without it once and the drink tasted sharper and one-dimensional. Two pinches won’t make it salty. They bridge the sweetness and the citrus so the whole glass tastes rounder.
For the sweetener, confectioners Swerve dissolves cleanly in cold liquid. Granular erythritol won’t. You’ll get gritty sediment pooling at the bottom of every glass. If you’d rather use allulose, I start at 1/3 cup and taste after mixing. It’s close enough in sweetness that the swap is nearly 1:1. And if you’re scaling up for a crowd, go easy. Erythritol gets bitter at high amounts and once it’s in, you can’t take it back. For a triple batch I start around 1.5 cups and adjust from there.
I make a batch of the strawberry base on Sunday and pour individual glasses over ice through the week. Fresh strawberries are best from May through September, but in winter I use frozen and the flavor is actually stronger (flash-frozen at peak ripeness beats February grocery-store berries every time). This is my sugar free summer staple, but it holds up year-round.
If you want the lemon without the berry, my plain keto lemonade uses the same freshly squeezed base. For a frozen version, pour it into molds for keto frozen lemonade pops. Add a shot of vodka and you’ve got a keto vodka lemonade. On really hot days I blend it with ice into something closer to a strawberry slushy, or go full cocktail with a keto strawberry daiquiri.
Ingredients
1 pint fresh strawberries -
4 cups of water
-
1 cup fresh lemon juice or lemon juice concentrate
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1/2 to ¾ c confectioners Swerve or use sweetener of choice
-
two pinches of salt
Step by Step Instructions
Step by Step Instructions
Cook strawberries
Add strawberries to a sauce pan and add 1/4 cup of water. Cook over medium heat until strawberries have released most of their juices. Remove from heat and let cool.
Strain strawberries
Push strawberries through a fine meshed sieve, strainer or cheesecloth to collect the strawberry juice. Discard the pulp.
Prepare the lemonade
Using a juicer or a citrus squeezer, squeeze the juice out of the lemons until you have 1 cup of freshly squeezed juice. Strain out lemon seeds and pulp by pouring the fresh lemon juice through a strainer.
Mix the lemonade base
Stir in water and powdered sweetener. Add two pinches of salt and mix until combined.
Nutrition disclaimer
The nutrition information provided is an estimate and is for informational purposes only. I am a Doctor of Pharmacy (Pharm.D.); however, this content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always consult your physician or other qualified health provider before making any lifestyle changes or beginning a new nutrition program.
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Can I use frozen strawberries instead of fresh?
I actually prefer frozen strawberries outside of summer. Flash-frozen berries are picked at peak ripeness, so the flavor is stronger than the pale, firm ones at the grocery store in February. I've made this with both, and the frozen batches consistently taste more like real strawberry. Thaw them first and drain off the excess water before cooking so your concentrate stays rich.
What sweetener dissolves best in cold lemonade?
I use confectioners Swerve because it dissolves completely in cold liquid with no gritty residue. Granular erythritol won't dissolve, and you'll feel it at the bottom of every sip. I've also tested liquid allulose and it works well. I start at 1/3 cup and taste after mixing. It's close to confectioners Swerve in sweetness, so the adjustment is minimal.
How long does sugar-free strawberry lemonade keep in the fridge?
I store mine in an airtight pitcher for up to 5 days. The strawberry base settles, so I give it a good stir before pouring. By day 3 the flavor leans a little more tart, so I've started keeping the sweetener separate and stirring it into each glass fresh. That way the first glass on Monday tastes as good as Sunday's.
Can I make this into popsicles?
I pour the finished lemonade straight into popsicle molds and freeze for about 4 hours. The texture is more icy than creamy since there's no fat, but the strawberry flavor is intense. My keto frozen lemonade recipe uses a similar approach if you want a slushier version instead.
How do I scale this recipe for a party?
I've tripled this for a party of 20 and it works fine in one pot. The strawberries cook down fast at any volume. The one thing I watch is the sweetener. Don't scale confectioners Swerve straight up. For a triple batch I start at about 1.5 cups and taste after blending. Erythritol gets bitter at high amounts and you can't undo it once it's mixed in. Easier to add a little more than to start over.
Can I turn this into a cocktail?
I add a shot of vodka per glass for a low carb spiked lemonade. Rum works too. The strawberry concentrate is strong enough that the alcohol doesn't wash out the flavor. For something more involved, my keto margarita uses a similar citrus-and-sweetener base if you want to go the tequila route.
How many carbs are in keto strawberry lemonade?
My recipe comes out to about 3-4g net carbs per serving, depending on the size of your strawberries and how much sweetener you use. Most of the carbs come from the berries and lemon juice. Swerve and allulose don't add to the count. I track mine at 3g per glass when I use the full pint of strawberries across 6 servings.
Is there a way to make this less tart?
I've played with the lemon ratio a few times. Start with 3/4 cup of lemon juice instead of a full cup and taste from there. I also find that adding a little more sweetener softens the tartness more naturally than just cutting the lemon. If it's still too sharp for you, try adding an extra 1/4 cup of water to dilute slightly without losing flavor.
One of my favorite drinks to order as a kid was strawberry lemonade. I loved the sweetness mixed with the tartness of the lemon. It’s easy to make a sugar-free version at home. Both lemon and strawberries fit into a low-carb diet since they’re naturally lower in carbs. For sweetness, I use a sugar-free sweetener. This lemonade was made for front porch sipping on a hot summer day.
Yes, lemons are fine. I use a squirt of lemon juice while cooking to add acidity to recipes. Lemons only have 3.4 grams net carbs each, so they fit easily into your macros.
Strawberries don’t have many carbohydrates compared to other fruits. Strawberries have 8.7 net carbs per cup of chopped berries. This recipe calls for about 2 cups of berries for the entire pitcher, so you only get a small amount of carbs per serving from the strawberries.
Made this on a whim Saturday because my kids were begging for something cold, and my daughter who has been skeptical of everything I've made lately took one sip and immediately asked if there was more. The part where you cook the strawberries down and strain them (I was nervous I'd mess it up) makes it taste like actual strawberries, not that artificial syrup stuff from a mix. She's already requesting this for her birthday party in June and I'm not mentioning it's sugar free.
Ha. The secret usually comes out eventually but by then they don't care. And yeah, cooking the berries down is the whole thing - raw strawberries would just taste thin.
I used frozen strawberries because that's what I had, and was genuinely nervous it wouldn't work the same way, but cooking them down still gave me that bright concentrated juice and the color came out gorgeous. This is going to be my whole summer.
OK so I started making just the strawberry concentrate in big batches to keep in the fridge, separate from the lemonade. Holds up like 5 days no problem. Mix a glass to order and it stays fresh every single time instead of a full pitcher going flat by day two. The thing I didn't plan for: I ran out of fresh strawberries once and used frozen, cooked them down the same way, and the concentrate came out way more intense. Like, that bright strawberry punch you get in the first sip was even stronger with the frozen ones. I've been doing it that way on purpose ever since. One more thing, if you're using lemon juice concentrate instead of fresh squeezed, bump the salt up just slightly. It cuts through that flat concentrate edge. The two pinches already in the recipe are doing more work than I gave them credit for before I started playing around with it.
The frozen thing tracks. Flash-frozen berries are picked ripe so the concentrate comes out more intense than fresh grocery store ones in February. And that salt note with lemon juice concentrate is something I've never actually written up. Useful.
Cooked the strawberries down a few extra minutes for more concentrate and the flavor gets freakishly intense in the best way (completely different drink). Ditched the Swerve for monk fruit and zero aftertaste. Finally.
Monk fruit was overdue for this one. Swerve's aftertaste is way more noticeable in something this tart than it is in, say, a cookie.
Froze the leftover strawberry concentrate in an ice cube tray instead of plain ice. Keeps everything cold without watering it down as it melts. Also threw a splash more lemon juice in before freezing, and that extra tartness as they melt is so good. Spring hit and I've been through a batch every week.
I've been using plain ice like a fool. The concentrate cubes make so much more sense. Extra lemon in before freezing, I need to try that.
Most sugar-free strawberry lemonades just taste like pink sweetener water. This one is actually tart. Pretty sure it's cooking the strawberries down first that does it. Made it twice this week already.
Yeah, that's exactly it. Cooked-down berries concentrate in a way raw strawberries just can't.
Made the strawberry base in a big batch Sunday and kept it in the fridge. Two minutes in the morning once that's done. By day three it gets a little more tart, so I just sweeten mine fresh now instead of pre-mixing the whole pitcher.
Yeah, day three it gets noticeably more tart. I do the same thing now - base in the fridge, sweeten per glass. Confectioners Swerve dissolves fast so it's barely any extra step.
I've made probably four or five keto strawberry lemonades this past year. Not one tasted like actual lemonade, just that sweetener flatness. Cooking the strawberries down and pushing them through a strainer is what changes everything here, the flavor concentrates in a way that just blending raw berries never does. This one actually tastes bright and a little tart, not just strawberry-flavored water with Swerve in it. Spring drink sorted.
The straining step is the one I almost cut during testing. That concentrated syrup is why it actually tastes like lemonade. Blending raw berries just gives you pink water.
My grandma made this from scratch every summer and I've missed it since going keto. The Swerve finish is a little different but it hits the spot.
That Swerve finish mellows out if you let it sit for a bit. If it's still noticeable, liquid allulose runs cleaner - I've used both and allulose is closer to the real thing.
My daughter's birthday is next Saturday and she asked for a pink lemonade, so I want to make this for her party. The recipe makes 6 servings but I'm feeding closer to 20. When I scale up the strawberries that much, can I cook them all in one pot or is it better to do smaller batches? I'm also nervous about the Swerve. I've heard it can get bitter when you use a lot. Would I scale the 1/2 cup straight up, or should I start low and taste as I go?
One pot is fine. Strawberries cook down fast anyway.
For the Swerve, don't scale it straight. Start around 1.5 cups for a triple batch and taste after blending. Erythritol gets bitter at high amounts, and once it's in, it's in. Much easier to add.
Made this four times now, and somewhere around batch three I switched to frozen strawberries instead of fresh (it's February, fresh ones taste like cardboard) and somehow the flavor got stronger, not weaker. Still messing with the Swerve amount but I'm not going back to fresh until at least June.
Frozen in winter is the better choice. Flash frozen at peak means stronger flavor than February strawberries at the grocery store. For Swerve I usually start at 1/2 cup and taste before adding more.
If I want to use liquid allulose, can you tell me how much I should use or do I just keep pouring it in to taste?
Start at 1/3 cup and taste after blending. Liquid allulose and confectioners Swerve are pretty close in sweetness so it shouldn't need much adjusting.
I really liked this drink. I used swerve and it tasted really good.
Swerve blends in so cleanly for this one. If you used the granular, try the confectioners version next time. Even smoother.