Lacto-Fermented Blueberries

Ever since I began making my own sauerkraut last year, I’ve been on a lacto-fermenting kick. I wanted to ferment everything in sight, and the Noma Guide to Fermentation has been good about providing inspiration for things to ferment, as well as narratives around their trials and errors. Lacto-fermented blueberries is one of the more popular Noma recipes, which the New Yorker also covered.

How do these lacto-fermented blueberries taste? The plump and juicy acidity that characterizes fresh blueberries evolve into a more mellow tang that’s rounded out with savory notes, and has a slightly jammy consistency that works really well as a yogurt topping. It evokes the flavor of umeboshi, or Japanese preserved plums. I also really liked the addition of roasted flax seeds with the fermented blueberries – the toasty, nutty, and crunch texture made this feel even more like a complete meal.

Lacto-fermentation is exceedingly straightforward, and requires minimum time or money investment – I highly recommend you give it a go.

LACTO-Fermented Blueberries

  • Some amount of blueberries
  • 2% of its weight in salt
  • Zip lock bag and a glass jar OR
  • A vacuum sealer and a vacuum sealing bag
  1. Rinse blueberries in tap water; just enough to rinse off any visible debris or dirt. You don’t want it to be completely sterile; the bacteria that’s naturally occurring on the skin of the fruit is what’s driving the fermentation process.
  2. Mix blueberries and salt in a bowl.
  3. Using a spatula, scrape blueberries and salt into the glass jar OR the vacuum sealing bag.
    1. If using a glass jar: Fill zip lock bag with water, and place it in the jar, covering the blueberries. Minimize the air exposure the blueberries will have by gently massaging the water-filled zip lock bag into the nooks and crannies the blueberries have created.
    2. If using a vacuum sealer: Ensure blueberries are in a a single layer in the bag. Vacuum seal it.
  4. Let the blueberries hang out in a dark corner for a bit, anywhere from 3 days (if it’s a hot summer’s day) to a week. I let mine hang out for four days at around 20 degrees Celsius and I think it could’ve gone two more days for extra funk.

Caramel Sauce

Sweet, unctuous caramel sauce with notes of vanilla and a nuttiness from the caramelized sugar. I’ve discovered that it works fantastic with cream biscuits. Drizzle a generous tablespoon of caramel sauce on a halved biscuit and you have a fireworks explosion of cream on cream in your mouth.

Caramel Sauce
Recipe adapted from Ina Garten, Food Network
Makes about 2 cups

1 1/2 cups sugar
1/3 cup water
1 1/4 cups heavy cream
1/2 teaspoon pure vanilla extract

Mix the water and sugar in a medium heavy-bottomed saucepan. Cook over low heat for 5 to 7 minutes, until the sugar dissolves. Do not stir. Increase the heat to medium and boil uncovered until the sugar turns a warm chestnut brown (about 350 degrees F on a candy thermometer), about 7 to 10 minutes, gently swirling the pan to stir the mixture. Be careful – the mixture is extremely hot! Watch the mixture very carefully at the end, as it will go from caramel to burnt very quickly. Turn off the heat. Stand back to avoid splattering and slowly add the cream and vanilla. Don’t worry – the cream will bubble violently and the caramel will solidify.

Simmer over low heat, stirring constantly, until the caramel dissolves and the sauce is smooth, about 2 minutes. Allow to cool to room temperature, at least 4 hours. It will thicken as it sits.