Algae’s Materials Moment: From Pond to Packaging

Published on October 1, 2025

From shoes to straws, algae are surfacing as a serious contender in the biomaterials’ revolution. Once known mostly as seaweed on a sushi roll or pond scum in a petri dish, both macroalgae (seaweed) and microalgae are now being tapped for their rich supply of polymers, fillers, and lipids that can either supplement or replace fossil-derived plastics. At the heart of this shift are materials like alginate, carrageenan, and ulvan, natural polymers extracted from seaweed, alongside lipids and cell-wall components harvested from microalgae. These compounds are finding their way into edible sachets, barrier coatings, and even EVA-like shoe foams, opening a sea of possibilities.

A landmark review of algae-based bioplastics outlines two core strategies:

Direct blending of algal biomass with conventional or biopolymers.
Cultivation of algae to produce intracellular biopolymers, such as Polyhydroxyalkanoates (PHAs), a class of biodegradable plastics synthesized by microorganisms.

Both routes are progressing rapidly, with recent studies (2024–2025) showing scalable systems that feed CO₂ directly to algae cultures to produce plastics, effectively linking carbon capture with material innovation.

From Marathons to Markets: Real-World Algae Applications

A headline-making example came during the 2019 London Marathon, where Notpla’s edible Ooho pouches replaced thousands of plastic water bottles and sachets, offering runners hydration with zero packaging waste.

Another hotbed of its innovation potential is in the footwear sector, where algae-derived foams from BLOOM have been integrated into Vivobarefoot shoes as well as DC Shoes’ IMPACT-ALG insoles, which demonstrate that biobased foams can meet durability and comfort standards, even when used in high-wear items.

The wave of innovation is not slowing down. Recent reviews track algae’s expansion into:

PHAs from CO₂-fed microalgae cultures
Biocomposites combining algae and biodegradable polymers
End-of-life strategies that match materials to composting, reuse, or recycling systems

Yet, there’s a catch. As Yale E360 cautions, bioplastics aren’t automatically sustainable. If mishandled, they can persist in landfills or generate methane, a potent greenhouse gas. This shows a clear case where success is hinged not only on the feedstock, but on the full circular infrastructure. Here are just a few of the eye-catching algae-powered products already hitting shelves or scaling up:

Edible or compostable packaging:

Notpla’s seaweed pods and takeaway boxes
Glenlivet’s glassless cocktail pods

Sustainable footwear:

BLOOM-based foams in Vivobarefoot
DC Shoes’ IMPACT-ALG insoles

Tableware from seaweed resins:

LOLIWARE’s “Blue Carbon” straws and utensils
SEADISH’s Ocean’s Tableware

Barrier coatings for paper and board:

Kelpi’s seaweed coatings (scaling with 2024 funding)
SWAY’s seaweed-based packaging line

It’s not a silver bullet, but a serious substitute as algae won’t replace all plastics. But as part of a broader circular system, they’re already making an impact. When combined with renewable energy, composting infrastructure, and thoughtful product design, algae-based materials can displace some of the most problematic single-use plastics in real-world applications. This is made more evident through the EU’s 2024 CORDIS results pack, which tracks dozens of funded projects bringing this potential to industrial scale. This is a clear statement showing that algae’s materials moment isn’t just a trend, but a transition.

The article was written by Christopher Kennard (reframe.food), Project Communication Manager.

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