How to make LAB (Lactic Acid Bacteria) culture
Checking the pH of the finished LAB culture - the pH should remain around 4.0 or under. (Some light brown yeasts have colonised the surface)
What: How to make Lactic Acid Bacteria (LAB) culture. This is a simple starter culture based on using rice, water, molasses and milk. It makes a culture of mainly fermenting bacteria called Lactobacillus.
Use: It can be used directly on soils and plants, as a compost inoculant and for many other purposes.
Benefits: LAB can increase soil health and populations of soil organisms. It can also be used as a foliar spray for added microbial benefits. As a foliar spray LAB can increase populations of beneficial microorganisms on the plant surface. A symbiotic relationship forms when lactobacillus eats the sugars or sap on the leaf. The microbe then provides pathogen protection to the plant. The microbe produces natural antimicrobial and antifungal compounds as waste. Compounds such as hydrogen peroxide, acetic acid, and lactic acid
Cost: It costs ~$0.35/litre to make (with relatively little effort) whereas may cost from $5 / litre (commercial quantities) to $35.00 / litre (retail quantities) if purchased so there is a significant incentive to produce this yourself
Notes: Many recipes on the internet suggest this method (or similar methods) produce Bokashi or EM1 (or sometimes more simply just EM – Effective Microorganisms). It is true that a large portion of Bokashi or EM1 is a Lactobacillus culture – and in fact many commercially available versions of Bokashi or EM1 are just that – principally a Lactobacillus culture. However true Bokashi should have three types of microbes including several strains of lactic acid bacteria, yeasts, and photosynthetic bacteria. Using this method is unlikely to have a final product with photosynthetic bacteria - though it will likely have several strains of yeasts. Note that many people use a LAB culture (perhaps unknowingly if purchasing a commercially produced product) in their Bokashi setup and appear to get very effective results – so the likely main driver of those results is the Lactobacillus culture. (I will do a subsequent blog on how to produce photosynthetic bacteria)
Acknowledgements: The following approach is largely derived from a biofertilizer workshop run by Soil Land Food but the author also acknowledges the work done by Juanfran Lopez who shared a similar approach at his biofertilizer workshops as well as Milkwood Permaculture and also Jadam’s Korean Natural Farming (KNF). Ever the tinkerer, the author has also made some adjustments to suit his on-farm set up.
Ingredients
Clean water - non-chlorinated or if chlorinated, i) bubble off the chlorine for a few hours, or ii) Boil the water for 20 minutes and then let cool, or iii) Add 10 mg of Vitamin C (ascorbic acid) per litre of water, or iv) Add a small amount of humic acid
Rice (any type)
Molasses
Milk (skim or full cream is fine – must have lactose so don’t use vegetarian based ‘milks’ such as oat / almond / soy etc). Can also make from milk powder – but be careful of calf raising mixtures as they often have antibiotics in them
Equipment
Buckets, measuring jug, pH tester, 20 pail/ 200L drums and / or IBC (or possibly something bigger – I am aware of one regenerative farmer who makes batches of 135,000L)
Batch Quantities:
METHOD
3 step process: -
Volumes given for 20/ 200 / 1000 L batch – but adjust on pro-rata basis for other quantities
1. Make rice water: Add 1.75 / 35 / 175 litres of water to a 2 / 40 / 200 litre barrel or IBC. Add rice to the water. Leave for 3 - 7 days in a sheltered place with a loose-fitting lid. Check the rice water each day. The liquid should change during this time. It should smell slightly sour and may have a slightly milky colour to it. When the liquid rice water has soured somewhat decant the water off and keep it. Throw away the rice (or use it in your compost). This liquid rice water is a culture mainly of Lactobacillus species.
2. Make whey: Now add this rice water to the 3.5 / 70 / 350 L of milk in a 10 / 200 / 1000 litre IBC with a wide lid. Cover with a loose-fitting lid and store for a few days until it curdles and milk solids separate. Remove and discard the solids (put in compost) with a scoop. Keep the creamy-yellow whey. You should have about 5 / 100 / 450 litres of whey
3. Make culture: Then add equal parts water (approx 5 / 100 / 450 litres) to this liquid whey. Add in 0.5 / 10 / 50 litres of molasses to the product. Leave for around 10 days with the lid loosely on. Protect from insects with mesh if needed. It will stop bubbling and giving off gas when it is finished. This is stable LAB Culture product. Check the pH of the product. It should be at 4 or just below. Visually check the liquid. It should be light to mid brown colour with a slightly sweet-sour smell. Store the product in a cool, shady place with the lid tightly on. Check fortnightly and gas out if needed If it is not used within a few weeks of making then seal the container tightly for long term storage. It should last for at least 6 to 24 months but it should be checked every few weeks to see if it is stable. Some light brown, pink or light grey yeasts may colonise the surface over time. This is OK. The pH should remain around 4 or under. The smell should remain the sweet/sour smell of lactic acid and molasses. If it is giving off gas you can take the lid off for a few hours every month or so.
Application rate:
Typically use at the rate of ~20L / Ha by blending up with water and spraying at the appropriate rate. Note that you should use within 24 hours once blended.