Lacto-Fermented Sweet Plums 2 Ways

Having discussed the nutritional value of fermented fruit and veg in the last post, here’s the tutorial for home fermented plums

The basic method for lacto-fermentation we covered in our Fennel Sauerkraut recipe

RECAP: A Few Notes Of Guidance

  • lactic-acid producing bacteria exist in and on virtually all fruit and veg
  • lacto-bacteria are salt resistant & beneficial for our health. Thus salting vegetables and fuit klills off harmful microbes allowing the healthy lacto-bacteria to fully colonize and preserve food without refrigeration as well as enhacing its nutrition and flavour intensity
  • different methods are available, requiring varying amounts of salt. Our sauerkraut used a 2%-by-weight ratio of salt to vegetable. We apply exactly the exact same principle to preparing lacto-plums
  • The proces of lacto-fermentation is anaerobic: it needs an oxygen-free environment. Thus, in addition to salting we have to prevent exposing our fuit/veg to oxygen

Simply put: get the salting and anaerobic conditions right and you’ll get brilliant results every time

preserving plums through fermentation

Lacto-Fermented Plums

A savoury-sweet condiment with a gentle sharpness and umami punch to give any dish a lift.
Lacto-fermentation needs oxygen-free conditions. Our previous recipe for fennel sauerkraut achieved this by keeping the fennel immersed in its own brine with the help of a weight.
This alternative method uses vacuum-seal bags where all the air is extracted by means of a pump. Professional vacuum bags are a bit of an investment, albeit a worthwhile one. We’ve had excellent results from using a simple manual pump whwich cost just pennies.
5 from 1 vote
Prep Time 5 mins
Cuisine world


  • 1 kg plums – firm, but fully ripe weighed after removing stones
  • 20 g mon-iodized salt


  • Wash your plums in fresh water just to remove any surface debris. I avoid over-rubbing so as not to remove too much of the surface bacteria.
  • Cut the plums in half and remove the stones.
    salt fermented lacto-plums
  • For best results use electronic scales: place the bowl on the scales and parse (zero) it. Weight the plums and calculate 2% of this which will be the amnount of salt needed: 1kg plums = 20g salt
  • Toss the plums to cover evenly with salt. Place them inside your vacuum-seal bags allowing a little space between them
  • Remove all the air using your pump. Place your bag in a warm place to ferment
    lacto-fermenting plums day 1
  • Fermentation takes 5-7 days, depending on the temperature. We get good results anywhere between 18-25 C. Avoid anything above 28C, which leads to too rapid a fermentation with a product over-high in acidity and somewhat lacking in complexity and umami.
    fermenting plums in vacuum seal bag
  • After a few days the bag will swell-up with carbon-dioxide. Burp your bag by releasing the gas and repeating the vacuuming process. At this stage you can start tasting the vinegar. You decide how much sharpness you want produced and how much sweetness you want preserved.
    fermenting plums with CO2 gas
  • Once fermented to your chosen level the plums are ready to use right away. Keep them in a jar or earthenware crock fully submerged in their vinegar. Refrigerate them to stop, or at least drastically slow down the fermentation. Cover them with a loose fitting lid to allow any further CO2 to escape

Using A Jar Or Fermentation Croc

Dehydrating the plums and skins

  • the plums and their skins can be dehydrated to concentrate thjir flavour. The plums acquire a firmer, chewier texture, rather like dried apricots and are delicious in salads, desserts or added to North african tagines and other Middle-eastern dishes using fuit. The skins can be dehydrated seperately till crisp and either crumbled over sweet and savoury dishes or ground to a fine powder and sprinkled as a tart-savoury-sweet garnish on hust about anything
    salt-fermented fresh lacto-plums
  • If you live somewhere very warm just lay them out in the sun until they reach the texture you want
  • Otherwise use a dehydrator set at 40C or oven dry them on the lowest setting possible – usually around 60C
    lacto-fermented diried plums and skins
  • The vinegar itself is tart but still deliciously fruity. use it in salds as part of the dressing. The Copenhagen-based Noma Restaurant have a wonderful recipe for a custard suffused with plum-vinegar. We added the vinegar from our last batch to a batter of rice and urid dal (washed back lentil) with black cumin seeds and hing spice before allowing the whole thing to ferment overnight for South Indian Iddly (recipe coming soon) for breakfast and Dosa for supper.
    fermented batter for dosa and idly


A savoury-sweet condiment with a gentle sharpness and umami punch to give any dish a lift.
Use in place of anchovies in Pasta sauces, oriental recipes Trom thai curries to Korean Kimchis and just about anywhere to add savoury-sweet complexity. Sun-dried they are deliciously chewy on their own, in all manner of salads or in North African tagines and stews.
Keyword condiment, fermented, no-cook, pro-biotic, vegan

2 Replies to “Lacto-Fermented Sweet Plums 2 Ways”

  1. Hi ,

    I tried the lacto fermented plum recipe from the Noma book but mine are not sweet at all . Saying that I think i got the last of the seasonal plums which were not too sweet to begin with . Is it extremely important that they should be sweet to begin with ?

  2. 5 stars
    Hi this looks like the info I’ve been needing. I have access to lovely plums but have not figured out how to lacto-ferment them, and my books are silent on the subject. So – muchas gracias!

    And – which manual pump you use to remove the air? In fact, if you linked it to your blog page it make you a few pennies.

    Thanks from the mountains of British Columbia!

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