Reencle vs. Mill: Which Electric Composter Actually Makes Real

Quick Answer: Both Reencle and Mill are premium kitchen appliances designed to deal with food waste — but they do not do the same thing. Reencle uses a living microbial culture to biologically decompose food into real compost. Mill uses heat and grinding to dehydrate food waste into dry material it calls "Food Grounds," which is intended for chicken feed or municipal composting — not direct garden use. If you want compost, the process that produces it matters.

Table of Contents

• How Each System Works
• What Does Each Produce?
• Head-to-Head Comparison
• What Does the Science Say?
• A Note on Subscription Models
• Which Is Right for You?
• Frequently Asked Questions
• References

How Each System Works

Both Reencle and Mill sit on your kitchen counter and accept daily food scraps. Beyond that shared starting point, they operate on fundamentally different principles.

Reencle: Biological Decomposition

Reencle is a sealed aerobic composting system. Inside the drum is a living culture of thermophilic microorganisms — heat-tolerant bacteria that actively break down organic material through biological decomposition. The unit maintains the temperature, humidity, and aeration conditions those microbes need to thrive, essentially replicating the conditions of a healthy outdoor compost pile in a controlled, odor-managed enclosure.

Food scraps added to Reencle are consumed by microbial activity over time. Proteins are broken down into amino acids, carbohydrates into simpler organic compounds, and fats into fatty acids — all through enzymatic and microbial processes, not heat destruction. What remains is a biologically active material containing living microorganisms, partially transformed organic matter, and the structural precursors to stable humus.

This is composting. Not as a marketing term — as a biological process.

Mill: Dehydration and Grinding

Mill works through a different mechanism entirely. The unit heats food waste at temperatures sufficient to evaporate moisture, then grinds it into a dry, shelf-stable material that Mill calls "Food Grounds." The process is closer to industrial food drying than to composting.

The heat involved in Mill's process kills beneficial microorganisms that might have been present in the food scraps. The output is dry, odorless, and dramatically reduced in volume compared to the original waste. Mill itself does not describe this output as compost. Their primary use case for Food Grounds is as an ingredient for chicken feed or as an input to municipal composting programs.

Both systems are well-engineered for what they do. The critical distinction is what they actually do.

What Does Each Produce?

Reencle: Biologically Active Compost Material

The material that comes out of Reencle's drum is biologically active. It contains living microorganisms, partially decomposed organic matter, and compounds that support soil microbiology. It is not, however, finished compost ready for immediate garden application.

Like all compost — including material from outdoor piles, tumbler composters, and vermicompost systems — Reencle's output requires a curing period before direct use. The recommended curing time is approximately 30 days. During curing, the material continues to stabilize, temperatures normalize, and the microbial community matures into a form that is safe and beneficial for plant roots.

After curing, Reencle's output functions as finished compost: it adds microbial life to soil, contributes organic matter that builds humus, improves soil structure and water retention, and provides a slow-release source of nutrients. It is a soil amendment in the genuine sense.

Mill: Food Grounds (Dehydrated Food Waste)

Mill's output — which the company officially calls "Food Grounds" — is a dry, shelf-stable material that has been heat-processed and ground. Because the processing involves sterilizing temperatures, the material does not contain living microorganisms. It has not undergone biological decomposition.

Mill's own guidance makes the intended uses clear: Food Grounds can be sent back to Mill via a subscription pickup service for use in animal feed programs (primarily chicken feed), or deposited in municipal composting streams where they serve as a carbon input. Mill does not position Food Grounds as a finished garden compost.

The distinction matters for anyone shopping in this category expecting a garden-ready output. Food Grounds and compost are not the same material and do not behave the same way in soil.

Head-to-Head Comparison

What Does the Science Say?

The central scientific question in this comparison is whether dehydration produces compost. The answer, by standard soil science definitions, is no.

Composting is defined as the biological decomposition of organic material by microorganisms under controlled aerobic conditions. The outputs of composting — stable humus, microbial biomass, and plant-available nutrients — are the products of that biological activity. The USDA, the U.S. Composting Council, and academic soil science literature are consistent on this definition.

Dehydration removes moisture and reduces volume through heat. It does not involve microbial decomposition. The dried output retains the organic compounds present in the original food waste but has not been transformed through biological activity. It is still, in chemical terms, food waste — just dried.

This matters practically when the dried material is applied to soil. Dry, carbon-rich organic material applied directly to garden beds can temporarily tie up available nitrogen as it begins decomposing in the soil — a phenomenon soil scientists call "nitrogen drawdown" or "nitrogen immobilization." Soil microorganisms consume nitrogen to break down carbon-rich material, which can temporarily deprive plants of the nitrogen they need. Fully finished compost does not cause this effect because the carbon has already been largely transformed.

Mill's guidance appropriately steers users away from direct garden application for this reason. Reencle's output, after curing, has already undergone substantial biological transformation and does not carry the same nitrogen drawdown risk.

For gardeners who want to improve soil biology — not just add organic bulk — the process used to produce the amendment is directly relevant to the result they will see in the garden.

A Note on Subscription Models

Mill's business model includes a monthly subscription service for the pickup and redistribution of Food Grounds. Check mill.com for current subscription pricing. Without the subscription, the practical utility of the Mill unit is reduced, since the Food Grounds must either be sent through the subscription service or disposed of through a municipal composting program (where available).

The ongoing subscription cost is a meaningful factor in the total cost of ownership.

Reencle does not require a subscription. The output stays with the user and goes directly into the garden. The only ongoing consumable cost is periodic replenishment of the microbial starter culture — a significantly lower recurring expense than a monthly pickup subscription.

Which Is Right for You?

This is a genuine trade-off decision, not a clear-cut one. Here is an honest framework.

Choose Reencle if:

• Your goal is to produce garden compost — to build soil biology and add finished organic matter to your beds
• You garden regularly and want a consistent, year-round source of compost from your kitchen
• You want to avoid an ongoing subscription model and keep the output of your system
• You are committed to the biological process of composting, not just volume reduction of food waste

Mill may be worth considering if:

• Your primary goal is reducing the volume of food waste in your home, and you are comfortable with the output going elsewhere (feed programs, municipal composting)
• You have no garden or minimal interest in using compost yourself
• You prefer the higher-capacity dehydration process and are comfortable with the subscription model
• Odor management is your highest priority, and you prefer the dry, odorless output of dehydration

The key is aligning your choice with what you actually want the output to do. If the answer is "go into my garden as compost," Reencle produces that. If the answer is "leave my house in the cleanest form possible," Mill's system serves that goal.

Frequently Asked Questions

Does Mill make real compost?

No. Mill's output — which the company calls "Food Grounds" — is dehydrated, sterilized food waste. It is produced through heat-based drying and grinding, not biological decomposition. Compost is the product of microbial activity breaking down organic material over time. Mill does not describe its output as compost, and their recommended uses (chicken feed, municipal composting input) reflect this. Mill's Food Grounds are not equivalent to garden compost and are not intended for direct soil application.

Can I use Mill Food Grounds in my garden directly?

Mill does not recommend direct garden application as the primary use case for Food Grounds. Dried, undecomposed organic material applied directly to soil can cause a temporary nitrogen drawdown as soil microbes begin breaking it down — potentially depriving plants of available nitrogen in the short term. Mill's subscription service routes Food Grounds into animal feed programs or municipal composting. If you want a garden-ready output, Reencle's biologically active material — after a 30-day curing period — is designed for that purpose.

Which is better for the environment, Reencle or Mill?

Both divert food waste from landfill, which is meaningfully positive — landfilled food waste produces methane, a potent greenhouse gas. Reencle's output adds organic matter back to soil, contributing to long-term carbon sequestration in the garden. One Reencle Prime unit offsets an estimated 0.39 metric tons of CO2 equivalent per year based on avoided landfill emissions. Mill's Food Grounds, when used in feed programs, displace some conventional feed production, which also carries environmental value. Both approaches are improvements over throwing food waste in the trash — the question is whether you also want a garden compost output.

Is Mill more convenient than Reencle?

Mill's dehydration process is largely hands-off and produces a dry, shelf-stable output that does not require active management of a living microbial culture. In that sense, it has a lower operational complexity. Reencle's living microbe culture requires more attention — you are managing a biological system, not just a machine — and the output requires a 30-day curing period. However, Reencle's subscription-free model means one less recurring task and bill. Convenience depends on what you weigh more: operational simplicity or subscription logistics.

Which is more expensive long-term?

Mill's total cost of ownership is generally higher over a multi-year horizon when the subscription is factored in. The Mill unit costs approximately $999 upfront (first year typically includes subscription). Ongoing subscription fees add $33–$45 per month, which totals roughly $1,200–$1,600 over three years of use. Reencle's upfront cost is approximately $499–$599, with periodic microbe culture replenishment as the primary ongoing cost — typically a fraction of Mill's monthly subscription. Over three to five years, Reencle's total cost of ownership is substantially lower for most users.

References

1. Reencle Official Product Page — reencle.com
2. Mill Official Product Page — mill.com
3. U.S. Composting Council — Compost Definition and Standards: compostingcouncil.org
4. U.S. Environmental Protection Agency — Composting At Home: epa.gov/recycle/composting-home
5. USDA Natural Resources Conservation Service — Soil Health and Compost: nrcs.usda.gov
6. Rynk, R. et al. — "On-Farm Composting Handbook," NRAES-54, Cornell University (1992) — foundational reference on aerobic composting biology
7. Magdoff, F. & Van Es, H. — "Building Soils for Better Crops," SARE Handbook (3rd ed.) — nitrogen immobilization and organic matter dynamics
8. BioCycle — Compost Quality and Maturity Standards: biocycle.net