The vitamin C carbon problem, and how a pharma partnership solved

Summary 

• The push towards sustainable progress in pharma is accelerating, but turning net zero ambitions into supply chain action remains a challenge, particularly when it comes to Scope 3 emissions.
• As a strategic partner to manufacturers in the pharma industry, dsm-firmenich is committed to addressing this challenge through ambitious and comprehensive sustainability initiatives - earning the Bayer Procurement Supplier Decarbonization Excellence Award in November 2025 for low-carbon vitamin C production at Dalry, Scotland.
• Read on to learn more about the partnership behind this decarbonization initiative, the specific steps that made it possible, and the transferable lessons for sustainable pharmaceutical manufacturing.

The pharmaceutical and nutrition industries exist to improve human health and wellbeing - a mission that naturally aligns with the UN’s goals for sustainable development (SDG 3). But as companies work towards net zero targets, they are increasingly accountable not just for their own emissions, but also for the emissions generated across their entire supply chain. This includes Scope 3, which covers indirect emissions across the value chain, from raw materials and ingredients to supplier manufacturing, transport, and product use and disposal.

Many manufacturers are working hard to address emissions outside of their own operations. They can take meaningful steps towards their sustainability goals by carefully selecting the right suppliers. However, maximizing impact depends on how effectively manufacturers and their partners can align on shared sustainability ambitions and decarbonization approaches. With greater transparency, investment, and collaboration, this alignment becomes a powerful opportunity to accelerate progress across the value chain.

Survey data from CPHI 2025 highlighted some of the key barriers companies face when addressing emissions. These include cost pressures (cited by 51% of respondents), regulatory complexity (36%), and responsible raw materials sourcing (34%). The knock-on effect of these challenges is visible in target adoption, where only 36% of respondents say they have Scope 3 targets—and around a quarter have no formal targets at all.

A recent decarbonization initiative driven by dsm-firmenich, in collaboration with global healthcare leader Bayer, demonstrates how companies in the pharma industry can combine expertise to turn these barriers into opportunities. Through a series of targeted investments and process improvements at dsm-firmenich’s vitamin C manufacturing site, the project has yielded results that are setting benchmarks for the future of sustainable pharma manufacturing. This article explores this specific example, what it took to deliver measurable results, and what the wider pharmaceutical industry can learn from it.

The opportunity: A high-impact ingredient for Scope 3 progress  

Vitamin C plays an important role across consumer health and pharmaceutical products, from immune support and antioxidant protection to helping meet the nutritional needs of vulnerable patient populations. As such, global demand is consistently high and stable year-round. Yet the production of vitamin C has traditionally been concentrated in coal-powered facilities, resulting in a significant cumulative environmental footprint.

For companies like Bayer, which utilizes vitamin C across a wide range of its portfolio, improving the carbon footprint of this single, high-volume ingredient can make a meaningful contribution to overall Scope 3 emissions reductions.  But achieving that improvement depends on working with suppliers who can offer lower-carbon alternatives - without sacrificing quality, traceability, and regulatory compliance.

dsm-firmenich identified vitamin C as one of its most significant emission drivers, and a priority within its own sustainability roadmap. As the sole vitamin C producer operating outside of Asia, dsm-firmenich was uniquely positioned to act - and in Bayer, found a customer that shared the belief that scientific innovation and collaboration are the drivers of sustainable progress in pharma.

“Because global demand for vitamin C is so high, even modest improvements in emissions per kilogram translate into significant carbon savings at scale. That also means the sustainability value of getting this right is outsized -not just for us, but for every customer and patient downstream.”

—Caroline Ploton, Global Sustainability Marketing Manager, dsm-firmenich HNC

The solution: Heritage manufacturing meets holistic sustainability

dsm-firmenich’s Dalry facility in Scotland was ideally placed to lead this initiative as the only vitamin C production site in the Western hemisphere. The site offered:

• Vertically integrated production, with key intermediates manufactured on-site, giving tighter control over processes, inputs, and efficiencies.
• Access to certified purchased renewable electricity, enabling immediate action on energy-related emissions.
• Proximity to partners and policy support in Scotland, facilitating collaboration on renewable energy, heat recovery, and circularity.

Underpinning all of this, the facility also has 70 years of vitamin C manufacturing expertise, a strong culture of process innovation, and a legacy of secure, traceable supply chains with an excellent long-term regulatory compliance record. These characteristics made Dalry the natural site to demonstrate what comprehensive, site-level decarbonization can achieve.

Over time, the dsm-firmenich team at Dalry has implemented a series of targeted improvements and modernization programs. The cumulative result was a holistic approach to sustainability, looking beyond isolated emission hotspots to consider the full system end-to-end. Working in close collaboration with Bayer to align on specifications, verification standards, and sustainability goals, these efforts have spanned five interconnected areas:

• Energy: The site was transitioned to 100% purchased renewable electricity, plus heat recovery and heat integration upgrades to reduce energy losses and therefore reliance on natural gas. These actions directly lowered the carbon intensity of the vitamin C supplied, contributing to meaningful Scope 3 reductions for Bayer.
• Process: Major optimization projects, including modernization of key production equipment and development of more efficient fermentation and catalysis processes resulted in improvements for both energy usage and product yield. These upgrades also enabled a reduction of chemical inputs, water consumption, and waste across production.
• Materials: On the input side, sustainable, traceable raw materials with lower embedded emissions were sourced, including GMO-free wheat from Germany and pure Scottish water. In terms of output, waste stream valorization improved circularity, achieving more than 90% waste reutilization, minimizing landfill and environmental contamination.
• Measurement: A third-party Life Cycle Assessment (LCA) was conducted, providing transparent emissions data for both dsm-firmenich and Bayer.
• People and community: The program also invested in training, safety, and the long-term resilience of the site and the surrounding community.

“Our approach at Dalry has been to evaluate every lever that influences vitamin C’s sustainability -environmental and beyond. It is this systematic, site-wide focus on improvement and modernization that has delivered deep, credible impact. The close collaboration with Bayer and our shared standards has ensured these results benefit both partners. That combination of holistic thinking and customer collaboration is what turned ambition into a working approach.”

—Caroline Ploton, Global Sustainability Marketing Manager, dsm-firmenich HNC

The results: Verified impact across environment, operations, and community

The headline result was that Dalry's vitamin C achieved a 49% lower carbon footprint compared to mainstream vitamin C alternatives, as confirmed by a third-party verified LCA aligned with ISO 14040/44 standards. The benefits extended beyond emissions too:

• Strengthened customer-supplier collaboration and data transparency, enabling Bayer to advance its own sustainability claims and reporting.
• Reduced operational risk, as greater efficiency and reduced reliance on fossil fuels means less vulnerability to energy-price volatility.
• Market differentiation, supporting sustainable product positioning in consumer and pharmaceutical markets.

These achievements were recognized in November 2025, when dsm-firmenich received Bayer's Procurement Supplier Decarbonization Excellence Award, selected from a field of 20 nominees.

“Through their innovative low-carbon vitamin C, produced via a process that combines clean energy and process innovation, dsm-firmenich is empowering Bayer to lead industry transformation and tackle the challenges of carbon-intensive production.”

—Malik Akhtar, Chief Procurement Officer, Bayer Consumer Health   

The bigger picture: From one ingredient to an industry blueprint

The Dalry project shows that significant emission reductions are achievable today - not only through future technologies, but through systems-level thinking and collaboration. The principles that made it work are not unique to vitamin C. They can be adapted across other essential nutrients, APIs, and performance solutions, supporting broader emissions reductions across the health and nutrition ecosystem.

For companies looking to apply this approach, four lessons stand out:

1. Collaborate early - customer-supplier alignment accelerates investment and scales impact.
2. Take a systemic view - analyze the full lifecycle to identify the key drivers for emissions and inform your decarbonization plan.
3. Invest in technology and process improvement—modernization supports both product yield and sustainability goals.
4. Measure rigorously and share transparently—third-party verified data builds credibility and helps drive collaborative decision-making.  

“The Dalry initiative is a blueprint, not a one-off. It demonstrates how genuine progress in pharmaceutical sustainability means going beyond environmental metrics alone, embedding supply chain resilience, quality assurance, and social responsibility into how we operate. We're excited to adapt and apply this approach for site-level decarbonization across other dsm-firmenich ingredients, working with our customers to drive the next wave of sustainable pharmaceutical manufacturing.”

—Kelsey Achenbach, Vice President Pharma, dsm-firmenich