Garbage Enzyme

Making an ‘Eco Enzyme’



Grade 5 Make Garbage Enzymes


The following information is taken from a document written by Datin Moo Siew Yoong and was originally developed by Dr Poompanvong of Thailand.

This eco enzyme is produced by the fermentation of kitchen scraps (fruit and vegetable waste only) with water and brown sugar.

The product has applications as a natural fertilizer and pesticide and an additive to animal feed. In the home it can be used for general cleaning, laundry and mould removal. It is also a good insect repellent, can unblock drains and be used to remove pesticides from fruit and vegetables. Not only then is it a way of using up old food waste, it takes the place of several harmful chemicals.

To make the enzyme combine 3 parts waste with 10 parts water and 1 part brown sugar in a sealable plastic container (e.g. in a 5 litre water bottle, add 3 litres of water, 300g of brown sugar and 900g of waste). Stir the mixture and close the lid. Release the pressure build up every day by opening the cap. The final enzyme can be filtered out using a sieve lined with a cloth after 3 months. Uses (and dilutions) are listed at the end of this page.

A Word of Caution from an excellent article in the Malaysian Star Newspaper....As a chemist I was skeptical about some of the claims made and this answers a lot of the hype. The final section shows the value of the process though and why we are encouraging students to try it.

Tuesday April 21, 2009

Enzyme pseudoscience


I WISH to point out that a lot of the facts championed by the garbage enzyme movement is largely inaccurate and falls perilously into the category of pseudoscience. I feel compelled to correct some of the myths and misrepresentations.

Garbage enzyme is nothing more than vinegar produced from organic wastes. It is essentially homebrew vinegar except that starch-rich food like rice is replaced with kitchen waste. The key ingredient is the sugar that is metabolised by bacteria into alcohol which subsequently is reduced to acetic acid (vinegar). Jaggery is used as impurities in it to ensure a supply of bacteria. The breaking down of sugar into alcohol releases carbon dioxide (CO2). This is why one has to open the container daily to release the gas and to ensure a supply of oxygen to promote aerobic fermentation. If there is insufficient oxygen in the mix, anaerobic process will take place, releasing methane. Methane and CO2 are poisonous to humans and therefore an airy place is a must to avoid inhaling excessive amounts of the gases. Both are also greenhouse gases.

It is not surprising that garbage enzyme works “wonders” in cleaning stuff as it is essentially vinegar. The weak acid is effective in dissolving oil. Acetic acid is also a good descaling agent that removes limescale. However, it is not advisable to use vinegar on metal surfaces as corrosion may occur in long term use. This is why it is recommended to use garbage enzyme in diluted form. Long term handling of the enzyme with care should also be advocated due to its corrosive effect on human tissues.

The insect-repelling effect of garbage enzyme is from the pungent smell of vinegar that is disliked by insects. The seemingly greening of plant leaves is probably due to the drying of acetic acid that forms a crystallised surface on the plant. Vinegar in diluted form has been used as fertiliser for ages.

The myths

Ozone is produced from garbage enzyme in fairly minute amounts compared to ozone of industrial origin. Besides being a very strong oxidising agent which is corrosive and an irritant, ozone is also a greenhouse gas at near ground level. The ozone that protects Earth from damaging radioactive sunrays is produced from interactions between high altitude oxygen and sunrays. If ground level ozone is beneficial and capable of repairing the ozone hole, the tonnes of ozone produced by industrial activity and automobiles would have done the trick. Sadly, the reverse is true.

It is claimed that ozone produced from garbage enzyme will reduce CO2 in the atmosphere. The contrary is true. The fermentation produces CO2 and ozone, if produced, will actually react with carbon to produce CO2 due to ozone’s strong oxidising properties. Hence there is a net increase of CO2 instead, but the fact that this CO2 comes from plants results in a near neutral carbon cycle.

Ozone is an unstable molecule and will react quickly with other substances. If ozone produced by garbage enzyme escapes from the container before reacting with the container contents, the interaction of ozone with heavy metals in the atmosphere will only transform the substances into acids that result in smog and acid rain.

It is claimed that garbage enzyme converts ammonia to nitrate, which is labelled as a natural hormone and nutrient for plants. Nitrate is inorganic and so is not a hormone. Although a nutrient to terrestrial plants, nitrate in sufficiently high concentration in waterways and in oceans causes algae booms and depletion of oxygen in water. Hence nitrate is considered a marine toxin.

It is also claimed that garbage enzyme converts carbonate and this is beneficial to sea plants and marine life. On the contrary, acetic acid attacks carbonates such as calcium carbonate – a compound found in rocks and shelled marine animals – and converts them to acetate salts plus CO2 and water. Acetate salts are hygroscopic and disintegrate easily, in turn causing the thinning of the shells of marine animals. Therefore it is not advisable to indiscriminately release acetic acid into waterways as it will end up in oceans. Acetic acid attacks on shelled marine animals may lead to the collapse of the marine ecosystem, already a phenomenon observable due to raising acidity of seawater.

The plus sides

Having said all of the above, there are advantages in making garbage enzyme. The benefits are: reduction in chemical cleaning agent; use of local materials and reduction in waste materials going to landfills; and less burden on the environment since organic cleaning agents are usually more biodegradable than petrochemical-based ones.

But one should introduce more oxygen to the fermenting solution (by stirring) to promote an aerobic process; place the enzyme-making container in airy places to prevent buildup of gases especially if you are producing the enzyme in large quantities; and handle the enzyme with care as if handling chlorine bleach.

Don’t pour garbage enzyme directly into drains as they connect directly to waterways and ultimately lead to the ocean. Only use garbage enzyme for cleaning within the bathrooms and kitchens as the waste pipes connect to treatment facilities (either a septic tank or sewer treatment plant), enabling the enzyme to further break down before reaching waterways. Don’t use garbage enzyme in concentrated form. – YSG

An overview of uses is given below. More detailed applications can be found in the Archives section of this site.



Vegetable and fruit wash

1 capful in a basin of water. Leave to soak for 40 mins


1 part bodywash:1part enzyme:8 parts water (Make markings on the side of the bottle to help)

Cleaning product

1 part original:1part enzyme:8 parts water (Make markings on the side of the bottle to help)


1 part enzyme:500 parts water


1 part enzyme:1000 parts water


1 part enzyme:100 parts water

Odour neutraliser

1 part enzyme:1000 parts water