Pre-Composting Appliances: Do They Work?

We get questions about pre-composting appliances often these days. Our verdict: While food scrap dryers and grinders can do amazing things, they cannot make compost in less than several months’ time. They are also not the most effective way to reduce your environmental footprint at home.

The Dirt on Countertop “Composters”

There are several kitchen appliances, such as the Mill kitchen bin and the Lomi kitchen “composter”, that dry and grind your food scraps. Mill turns the end product into chicken feed, whereas Lomi claims that its finished scraps can be added directly into the soil. In reality, it isn’t possible for large quantities of food waste to be effectively processed in a short period of time. Effective compost requires a proper proportion of vital nutrients such as nitrogen, carbon, and oxygen, of which food scraps only provide some.

So what is the best way to use these countertop kitchen appliances? Dig small holes throughout your yard, place your dehydrated food scraps in them, and mix thoroughly to avoid over-saturating your garden with specific nutrients. In larger quantities, the partially-processed food scraps will eventually decompose, but may potentially cause damage to nearby plants or make the soil less hospitable to future seedlings or plantings.

Food Waste Prevention is #1

To clarify, preventing food waste in the first place is the best way to make a difference in household methane emissions. Methane has 80 times the warming power as carbon dioxide in the first 20 years after it reaches the atmosphere, making a significant difference in how life will be experienced by future generations. Visit the Food Waste Prevention Week website for useful info on how to shop smart to reduce food waste, what sell-by dates actually mean, and how to keep food longer and use food scraps in recipes.

Of course, sometimes you will still have food waste, and that’s where green bins, compost, bokashi, and pre-composting appliances can come in. As for overall environmental impact, pre-composting appliances can be great for people who dislike the decay of food scraps in green bins or bokashi buckets or don’t have freezer storage to store scraps before curbside pickup day. They’re also great for people who want to spend less time heading to their backyard compost bin or taking their food waste to a community compost program such as Food Cycle at Solana Center.

Feed people and animals before the landfill!

Source: U.S. E.P.A.

According to the United States Environmental Protection Agency, reducing surplus food generated, feeding hungry people, and feeding hungry animals should happen before composting. Composting should be the last resort for inedible food.

Since the Mill compost bin turns food scraps into chicken feed, it does fall higher on the E.P.A.’s food waste prevention hierarchy than composting. On the other hand, mailing food grounds does increase carbon emissions. Since no thorough studies on Mill’s overall environmental impact have been undertaken yet, the jury is still out on the overall benefit.

In conclusion, pre-composting appliances can be useful in specific scenarios for specific individuals. Though a kitchen grinder does not compost make, the resulting grounds will not be detrimental to your garden if spread out through time and space. Please write to us at to share your experience using any pre-composting appliances; we’d love to hear how it works for you!