When a better LCA
changes the answer

Amber Numamoto, UNROOTED’s Head of Operations and Sustainability, came to alkatera in January 2026 looking for a better way to calculate the company’s impact: something she could use in real time, update easily, and not rely on third party inputs she no longer trusted.

UNROOTED had stopped calling themselves carbon neutral in 2024. From 2021 to 2024 they spent over £9,200 on carbon credits, and decided that money was better spent reducing emissions than offsetting them, something we wholeheartedly agree with. Dropping the claim meant the underlying numbers had to carry more weight, because there was no longer a purchased balance sitting on top of them.

They are also a certified B Corp, scoring 85.1 in 2023. Early in 2026 B Lab launched new standards making certification far more rigorous: independent verification replaces self-reporting, and every company must meet minimum standards across all seven impact areas, with no more offsetting a weak area with a strong one. UNROOTED recertify under the new standards in early 2027.

UNROOTED’s first full life cycle assessment was completed in 2022 for the 2021 data year. It was competent, ISO 14040 aligned, and honest about its own gaps. It was also, on inspection, carrying an error large enough to over-report on several areas of the company’s emissions.

The assessment measured one product: a single Mighty Ginger 60ml shot, chosen because it was the highest seller. That one model was then applied to the similar products and scaled for the larger formats.

Within that model, material production accounted for 72% of the product’s footprint, and glass bottle production accounted for 75% of material production. In other words, the glass bottle alone was more than half of everything.

The glass figure rested on two assumptions. The first was that producing one 66-gram glass bottle required 6.236 kWh of energy. For scale, that is roughly what a domestic fridge-freezer uses in a week. The second was that 30% of all glass bottles break during manufacturing, and that this loss should be added to every bottle’s footprint. Neither is in line with widely accepted data.

Neither assumption was invented. Both were reached honestly, by people filling gaps in supplier data with the best published material they could find. That is the point.

Elsewhere in the same assessment, the energy required to process baobab powder was estimated by taking Zimbabwe’s national per-capita annual electricity consumption, dividing it by 52 weeks and then by five working days. Lime farming was modelled on lemon farming in Spain. Label ink was calculated from an ink cartridge retailer’s page-yield page. And all of it was reported to four, five, sometimes seven significant figures.

There was one more issue, working in the opposite direction. The old model counted the energy cost of recycling as an emission and gave no credit for the virgin material that recycling avoids. Total end-of-life impact came out as a small positive burden. In a product whose packaging dominates its footprint, that is a meaningful omission.

kg CO2e per 60ml shot

Share of total product footprint · bars left of the rule are credits, not burdens

Two rows matter most. End of life moved from a small positive burden to a credit worth −0.0126 kg CO2e, because recycling now displaces virgin material instead of merely costing energy. On a product totalling 0.087 kg, that swing is one of the largest single differences between the two assessments.

And the glass bottle, which was more than half of everything in the old model, is now the largest contributor at around 37% rather than the whole story. Distribution looks like it grew, but that is because routes are now modelled individually rather than averaged into one 75-mile journey.

That is the propagated uncertainty on the result. It is calculated by root-sum-of-squares on geometric standard deviations, using the Pedigree Matrix to score every input for reliability, completeness, and temporal, geographic and technological representativeness.

The old assessment reported 0.2114 kg CO2e. Four decimal places, no range, no confidence interval, no sensitivity analysis. That is not a criticism of the people who wrote it so much as a description of what LCA reporting looked like before uncertainty propagation became standard practice. But it is the difference between a number and a measurement.

The rebuilt report also names its own weakest point. It flags the glass bottle as secondary data at medium quality, 50% confidence, marks it as the single most sensitive parameter in the model, and recommends engaging the supplier for primary verified data. A ±20% swing in that one factor moves the whole product result by ±8%.

An assessment that tells you where it is least certain is more useful than one that does not, even though it reads as less confident.

The old assessment stated that it captured 99% of emissions and that its completeness check found nothing affecting accuracy by more than 1%. Both statements were true as written. Neither would have caught a glass factor that was carrying half the product’s footprint.

From 2027, under the rebuilt B Corp standards, that distinction stops being academic. Self-reported footprints give way to independently verified ones. A verifier looking at a 2021-era model will go straight to the largest line item and ask where the number came from. “A photography feature about glass recycling” is not an answer anyone wants to give.

The last one is the tell. If the provenance is not recorded, the number cannot be verified, and in eighteen months that will be the only kind of number that counts.

UNROOTED are now scaling a biochar project in Zimbabwe with Carbon Connect and Carbon Future, converting baobab shells that would otherwise be discarded into a carbon sink. Their first purchase of biochar carbon removal credits in January 2026 matched the exact volume of shell by-product created by the baobab they bought in 2025.

We will also be assisting them in preparing for B Corp recertification in 2027, working through every tier of their supply chain using our dedicated B Corp tool that works as a step by step guide through the entire process.

“Environmental legislation is changing at a rapid pace, and that shift is going to influence every company, not just at the enterprise level, but for SMEs like UNROOTED. It’s critical that we stay ahead of the game. alkatera makes that simple. The methodology is visually reliable: you can see where the data is sourced, where you need to improve, and what the next step should be.”