Kefir Berry Smoothie

Before you start

Kefir is a cultured milk drink made by fermenting milk with kefir grains or a starter culture. It is thinner than yogurt and noticeably tart, with a slight fizz in some brands. In a smoothie it acts as both the liquid and the creamy element, adding a pleasant tang that makes berries taste brighter.

The main thing to manage is acidity. Plain kefir is quite sour, and paired with tart berries the result can be sharp. A little honey and some banana or mango balance it out. Store-bought plain kefir is the easiest choice, and you can buy whole-milk or low-fat versions. Because kefir is already thin, use mostly frozen fruit and skip extra liquid at first.

Ingredients

• 240 ml (1 cup) plain kefir — whole milk or low fat
• 150 g (1 cup) frozen mixed berries
• ½ small frozen banana — or 75 g frozen mango
• 1-2 tsp honey — to taste
• 1 tbsp ground flaxseed or rolled oats — optional, for thickness
• Splash milk or water — only if needed

Method

1. Shake the kefir container well; the cultures and fat can settle.
2. Pour the kefir into the blender, then add the honey and flaxseed or oats if using.
3. Add the frozen berries and banana or mango.
4. Blend on high for 40 to 50 seconds until smooth and evenly purple.
5. Taste. If it is too sour, add more honey; if it is too thick, add a splash of milk. Pulse to combine.
6. Pour into a glass and drink right away.

Tips for success

• Plain kefir is best; flavored kefirs often contain a lot of sugar.
• Blueberries and strawberries are milder than raspberries and blackberries, so choose them if you want a less tart smoothie.
• Some kefirs are slightly fizzy. Blending releases the bubbles, which can make the smoothie foam; let it stand a moment before pouring.

Substitutions

Kefir

Thin plain yogurt with milk (about 2:1) for a similar tang; it is less sour than kefir.

Frozen berries

Frozen cherries, peaches or mango all work; mango is the sweetest and softens the tartness.

Honey

Maple syrup or a pitted date sweetens it; a date also adds body.

Variations

Green kefir

Add a handful of baby spinach and use mango instead of berries.

Kefir peach

Use frozen peaches and a pinch of cinnamon.

Troubleshooting

Too sour

Kefir and berries are both tart. Add honey, a sweeter fruit like banana or mango, or a little milk.

Too thin

Kefir is a pourable liquid. Add more frozen fruit or a spoon of oats or flaxseed.

Overly foamy

Fizzy kefir was blended at high speed. Let it settle for a minute or stir gently before drinking.

Storage

Drink fresh. Keep opened kefir refrigerated at 4°C (40°F) or below and use it by the date on the container; discard it if it smells off or shows mold. Smoothie leftovers keep covered in the fridge up to 24 hours.