Bokashi – An ancient concept with a modern twist.

Article by Piet Kruger

I was recently contacted by Rupert Van Der Merwe, owner of a business producing and selling a range of EM based products. One of the ranges that the business manufactures is Bokashi bran that is used in Bokashi fermentation.

It would come as no surprise to hear me confess that I have always had a thing for strange and exotic biological conversion processes, and consequently my fascination with the Bokashi process started many years ago. When Rupert explained what their business was all about, I thought it to be just the excuse I needed to write a short article about Bokashi.

Bokashi Fermentation

Bokashi is primarily a fermentation process where a specifically formulated bacterial-based inoculum is added to a substrate in order to accelerate the decomposition of organic fractions present in a wide variety of organic waste products.

Rupert Van Der Merwe – promoting the use of Bokashi as a food waste recycling method

Bokashi is by no means a new concept and has been a favorite of Japanese farmers for hundreds of years. Bokashi compost is somewhat of a strange beast as far as traditional composting methods go unless one understands the underlying principles.

It’s All About The Bugs

Adding specific bacteria to a substrate to achieve a specific end result is nothing new – everyday products like cheese, bread, yoghurt, beer etc all rely on microbial and bio-enzymatic interaction to become the product that we know.

On a more industrial scale, biogas facilities employ specific microbial consortiums to boost yields of methane and accelerate gas production. Sewage treatment facilities use a variety of inoculums that assist with sludge degradation, hydrolysis, odor control, de-nitrification etc.

Farmers that are familiar with the process of making silage have often commented that the silage process is quite similar to that employed by Bokashi composting except that the addition of Bokashi microbes steers the degradation pathway in a different direction resulting in a drastically different end product.

Why Anaerobic?

It is a known fact that anaerobic organisms are better suited to breaking down fat than their aerobic counterparts. This is a highly desirable characteristic when dealing with food waste which is typically high in grease and fat.

Anaerobic fermentation does not decrease the dry-matter content of the substrate to such an extent as is found in aerobic degradation. More dry matter equals better water holding capacity and a higher carbon content.

Anaerobic fermentation requires less physical inputs and is generally speaking a much easier process to implement on a small scale.

Bokashi fermentation is carried out in closed, airtight vessels and therefore process odor is not really a factor.

In Conclusion

A question that pops up frequently is what I think about Bokashi composting and what my recommendations are. I always point out that every system has its own field of application, merits and disadvantages, and Bokashi is certainly no different in this regard.

In a nutshell, I think Bokashi is a very effective small scale recycling process as long as the microbial consortium (Bokashi Bran) originates from a credible supplier that has the technical capabilities to verify and certify their products.

When used in the right context, it can be a wonderful method to recycle certain products. On the other hand, Bokashi-like any biological system -cannot provide a pathogen-free final substrate, and in my opinion should not be considered to ferment products that may be biologically hazardous.

My advice – if you’re in the food industry and looking for a small scale recycling solution for two or three buckets of kitchen waste per day, Bokashi is certainly one of the options out there.

Till next time then..