How to Manage Odour in Pet Food Manufacturing: Proven Technologies & Regulatory Insights
The pet food manufacturing industry has grown significantly in recent years, driven by increasing pet ownership and demand for high-quality, specialized pet nutrition. However, one of the persistent challenges in this sector is managing odours generated during production. The processing of animal proteins, fats, and other organic materials creates volatile organic compounds (VOCs), sulfur compounds, and amines, which produce strong, often unpleasant odours. These odours can affect worker safety, community relations, and regulatory compliance. Effective odour control is thus critical for operational success, environmental responsibility, and maintaining a positive public image.
This article explores the sources of odours in pet food manufacturing, their impact, and the technologies and strategies available for effective odour management. It also examines Regulations, industry best practices, and emerging innovations, providing a comprehensive guide for manufacturers seeking to mitigate odour-related challenges.
Pet food manufacturing involves several processes that contribute to odour emissions, including raw material handling, cooking, extrusion, drying, and packaging. Understanding these sources is the first step in designing effective control measures.
1. Raw Material Handling
Pet food production often begins with the receipt and storage of raw materials such as meat, fish, poultry by-products, grains, and fats. These materials, particularly animal-based ingredients, can emit odours during unloading, storage, and preprocessing. Decomposition of organic matter, especially if storage conditions are suboptimal, exacerbates the issue.
2. Batching and Grinding
The raw materials or all the ingredients defined based on the formulation of the company, including protein sources such as fishmeal, chicken-meal etc. are grinded along with the other materials. During this time there will be VOC and dust generation, which will be handled in a bag filter. The dust gets trapped in the bag filter but the exhaust air after the bag filter will be having VOCs and that causes odour emission from the process.
3. Cooking
A key process in which animal by-products are cooked at high temperatures (often exceeding 120°C), leading to the release of VOCs, including aldehydes, ketones, and sulfur-containing compounds like hydrogen sulfide (H₂S). These compounds have low odour thresholds, meaning even small concentrations are detectable and potentially offensive.
4. Extrusion and Drying
Extrusion involves mixing, cooking, and shaping pet food under high pressure and temperature. The process releases steam and volatile compounds, contributing to odour emissions. Drying, used to reduce moisture content in kibble or treats, further volatilizes organic compounds, releasing them into the exhaust air.
5. Packaging and Storage
While less intense, odours can also arise during packaging if residual volatile compounds are released from freshly processed products. Improperly sealed storage areas may allow odours to escape into the surrounding environment.
Odour emissions from pet food manufacturing have wide-ranging implications:
Given these impacts, effective odour control is not just a technical necessity but a strategic priority for pet food manufacturers.
Odour regulations vary by region but generally aim to limit nuisance and protect air quality. In the United States, the Environmental Protection Agency (EPA) and state-level agencies enforce standards under the Clean Air Act, which may include limits on VOCs and hazardous air pollutants (HAPs). Facilities must also comply with local zoning laws and nuisance ordinances.
In the European Union, the Industrial Emissions Directive (2010/75/EU) sets guidelines for managing emissions, including odours, from industrial processes. Member states often have additional requirements, such as Germany’s Technical Instructions on Air Quality Control (TA Luft), which specify odour thresholds.
In Australia, the Environmental Protection Authority (EPA) in each state regulates odour emissions, often requiring facilities to conduct odour impact assessments and implement control measures. Similar frameworks exist in Canada, where provincial governments oversee compliance.
Pet food manufacturers must stay informed about applicable regulations and engage with regulatory bodies to ensure compliance. This often involves monitoring emissions, modeling odour dispersion, and reporting to authorities.
A range of technologies is available to control odours in pet food manufacturing, each suited to specific processes and compounds. These can be broadly categorized into physical, chemical, and biological methods, often used in combination for optimal results.
1. Physical Methods
2. Chemical Methods
3. Biological Methods
Beyond installing control technologies, pet food manufacturers can adopt operational and strategic practices to minimize odours:
1. Process Optimization
2. Facility Design
3. Monitoring and Modeling
4. Community Engagement
5. Training and Maintenance
If you’re looking for reliable pet food odour control, Elixir Enviro Systems is your trusted partner. We specialize in industrial odour treatment, wastewater management, and biofiltration systems for factories and processing plants.
With years of experience, Elixir offers complete solutions—from design and installation to testing and maintenance. Whether your facility needs scrubbers, biofilters, RTOs, or real-time odour monitoring, we’ve got you covered.
✅ Pioneer in Industrial Odour Control in India
✅ Largest player in India having treating about 1 Million cubic meter of air each hour
✅ Experts in pet food manufacturing odour control
✅ Custom solutions for industrial odour problems
✅ In-house R&D and simulation tools
✅ Onsite odour audits and pilot testing
✅ Solutions that meet all local and global regulations
Visit www.elixirenviro.in to learn more or contact us for a custom consultation on odour control for your facility.
Odour control in the pet food manufacturing industry is a multifaceted challenge requiring a combination of advanced technologies, operational best practices, and community engagement. By understanding the sources of odours—raw materials, batching-Grinding, extrusion, and wastewater—manufacturers can deploy targeted solutions like scrubbers, biofilters, and oxidizers. Regulatory compliance, worker safety, and environmental sustainability further underscore the importance of effective odour management.
As industry continues to grow, so too will the need for innovative, cost-effective, and eco-friendly odour control strategies. Manufacturers that invest in these solutions will not only mitigate risks but also strengthen their reputation as responsible corporate citizens. By prioritizing odour control, the pet food industry can ensure a harmonious coexistence with communities and a sustainable future for pet nutrition.
Q1. What causes odour in pet food manufacturing?
A: Odours are primarily caused by raw material handling, grinding & batching of ingredients, extrusion, drying, and improper wastewater management. These processes release VOCs, sulfur compounds, and amines.
Q2. How can odour emissions be controlled in pet food factories?
A: Odour control can be achieved using technologies like biofilters, wet scrubbers, regenerative thermal oxidizers (RTOs), and proper ventilation systems. Process optimization and regular maintenance also play a crucial role.
Q3. Are odour control systems mandatory for pet food manufacturers?
A: In many regions, yes. Regulatory bodies like the US EPA, EU’s Industrial Emissions Directive, and local environmental agencies require odour emissions to be controlled and monitored. Other locations around the globe mostly have nuisance law, meaning if the neighborhood complains, the factory might need to shut down until the issue is rectified. Considering this, the cost of installation of the Odour Control Unit surpasses the disadvantages of legal penalties, factory-closures and poor neighborhood relationships.
Q5. What role does Elixir Enviro Systems play in odour control?
A: Elixir Enviro Systems offers turnkey odour control solutions tailored to pet food manufacturing, including biofilters, scrubbers, oxidizers, and real-time monitoring. They also provide audits and pilot testing to ensure effectiveness.
Proven Strategies to Keep Emissions and Nuisance Odours in Check
Composite vessels made from FRP, GRP, and SMC are the backbone of many industries—offering unmatched strength, corrosion resistance, and design flexibility. But behind these advanced materials lies a quieter challenge: the odours generated during manufacturing. These emissions, primarily from resin curing and finishing operations, can affect worker health, community relations, and regulatory compliance. In this blog, we explore the sources of odour in composite vessel production and share proven strategies to control them—so manufacturers can deliver high-performance products without compromising air quality or reputation.
FRP (Fiber-Reinforced Plastic) refers to a broad category of composites made from a polymer matrix reinforced with fibres such as glass, carbon, or aramid. GRP (Glass-Reinforced Plastic) is a subset of FRP, where the reinforcing fibre is glass. SMC (Sheet Moulding Compound) is a type of pre-impregnated fibre composite, usually consisting of chopped glass fibres and thermoset resins, used in compression moulding. These materials are popular for vessel manufacturing due to their excellent mechanical properties, lightweight nature, and corrosion resistance. However, many of the resins used—particularly polyester and vinyl ester—emit volatile organic compounds (VOCs) like styrene during processing. These emissions are the primary source of odour and present both environmental and health concerns if not properly managed. Let’s first dive into little more details on each material.
A. GRP: Definition and Composition
GRP (Glass Reinforced Plastic) is a composite material composed of glass fibres, such as E-glass or S-glass, embedded in a plastic resin matrix, typically polyester, vinyl ester, or epoxy. The term emphasizes the use of glass fibres as the primary reinforcement, making GRP a specific subset of fibre-reinforced composites. It is widely chosen for its balance of strength, corrosion resistance, and affordability.GRP offers good mechanical strength, excellent corrosion resistance, and moderate stiffness, though it is heavier than carbon-based composites. It is cost-effective and ideal for large structures like storage tanks, pressure vessels, pipes, and marine vessels such as boat hulls. GRP is commonly used in industries like water treatment, air pollution control, chemical storage, oil & gas, and marine applications due to its durability and resistance to harsh environments.
B. SMC: Definition and Composition
SMC (Sheet Moulding Compound) is a composite material made of chopped glass fibres (typically 25-50 mm long) mixed with a thermosetting resin, usually polyester, along with fillers like calcium carbonate and additives. Supplied as mouldable sheets, SMC is designed for compression moulding, enabling the production of complex shapes with consistent thickness and high-quality surface finishes.SMC provides good mechanical strength, dimensional stability, and an excellent surface finish, but its shorter, chopped fibres result in lower strength compared to continuous-fibre composites like GRP for high-load applications. It is well-suited for smaller, intricate components such as covers, enclosures, automotive panels, or small tanks, where high-volume production and aesthetic quality are priorities. SMC is less common for large vessels due to its structural limitations, being that said, many companies have come up with designs with steel supports making the SMC panel tanks suitable for somewhat larger applications as well.
C. FRP: Definition and Composition
FRP (Fiber Reinforced Plastic) is a broad category of composites that includes any type of fibreglass, carbon, aramid, or basalt—embedded in a plastic resin matrix. GRP is a type of FRP when glass fibres are used, but FRP also encompasses high-performance fibres like carbon or aramid. This versatility allows FRP to be tailored for a wide range of applications, from general-purpose to specialized uses.FRP’s properties vary by fibre type: glass-based FRP (like GRP) offers corrosion resistance and moderate strength, carbon-based FRP provides a high strength-to-weight ratio and stiffness, and aramid-based FRP excels in impact resistance. Glass-based FRP is used for tanks and pipes, like GRP, while carbon or aramid-based FRP is employed in aerospace, automotive, high-pressure vessels, and advanced marine structures like aircraft components or high-performance yachts. FRP’s cost ranges from affordable (glass) to expensive (carbon/aramid), depending on the fibre and manufacturing process.
Odour control in FRP/GRP manufacturing is far more than a matter of comfort—it’s a critical aspect of health, safety, and compliance. The Odours are largely caused by VOCs, such as styrene, a common component in polyester and vinyl ester resins. Prolonged exposure to styrene and similar compounds can lead to respiratory issues, neurological symptoms, and other health problems for workers. Additionally, regulatory agencies worldwide impose strict limits on VOC emissions to safeguard air quality and public health. Non-compliance can result in significant fines and legal challenges. Beyond regulations, persistent Odours can strain relationships with neighbouring residents and businesses, potentially damaging a company’s reputation. Effective Odour management, therefore, is essential for worker well-being, regulatory adherence, and maintaining community goodwill.
The manufacturing of GRP (Glass Reinforced Plastic), SMC (Sheet Moulding Compound), and FRP (Fiber Reinforced Plastic) vessels involves processes and materials that can release odorous compounds. The primary sources of odours stem from the resins, solvents, and additives used, as well as specific manufacturing techniques. Below is a detailed breakdown of the odour sources for each material, organized by material type.
A. GRP Vessel Manufacturing: Odour Sources
GRP vessels are made using glass fibres and thermosetting resins (e.g., polyester, vinyl ester, or epoxy) through processes like hand lay-up, filament winding, or resin transfer moulding (RTM). Odour sources include:
(i) Resins (Styrene Emissions):
(ii) Solvents and Thinners:
(iii) Curing Agents and Catalysts:
(iv) Open-Mold Processes:
(v) Dust and Fumes:
B. SMC Vessel Manufacturing: Odour Sources
SMC is a pre-mixed composite of chopped glass fibres, polyester resin, fillers, and additives, moulded into sheets and compression-moulded under heat and pressure. Odour sources are generally less intense than GRP due to the closed-mould process but still significant:
(i) Resins (Styrene and Other VOCs):
(ii) Additives and Fillers:
(iii) Compression Moulding:
(iv) Solvents for Equipment Cleaning:
(v) Post-Moulding Finishing:
C. FRP Vessel Manufacturing: Odour Sources
FRP encompasses a broad range of composites, as an umbrella category, FRP includes both GRP and SMC, but also other forms like carbon-reinforced or aramid-reinforced plastics, or other fibres, using resins like polyester, vinyl ester, or epoxy. Odour sources depend on the fibre and process but overlap with GRP for glass-based FRP:
(i) Resins (Styrene and Epoxy Emissions):
(ii) Solvents and Cleaning Agents:
(iii) Curing Agents:
(iv) Manufacturing Processes:
(v) Fiber-Specific Odours:
The manufacturing of GRP (Glass Reinforced Plastic), SMC (Sheet Moulding Compound), and FRP (Fiber Reinforced Plastic) vessels involves resins, solvents, and additives that release odourous volatile organic compounds (VOCs), notably styrene from polyester resins. These odours, described as pungent or chemical, can affect worker health, community relations, and regulatory compliance. Effective odour control strategies are essential to mitigate these emissions, improve workplace safety, and adhere to environmental standards. The odour control strategies are categorised into two – process/product specific odour control strategies with respect each product and End of pipe solutions applicable for all the three products. First, we will cover few tailored strategies for each material, focusing on ventilation, material selection, process optimization, and followed by end-of-pipe solutions or advanced filtration methods.
A. GRP Vessel Manufacturing
(i) Ventilation and Air Extraction Systems:
GRP vessel manufacturing frequently employs open-mould techniques such as hand lay-up or spray-up, where styrene-rich polyester resins are exposed to air, resulting in significant VOC emissions. To address this, robust ventilation systems, including local exhaust ventilation (LEV) systems, are critical. These systems are installed at key emission points, such as resin application and curing stations, to capture odorous air. Regular maintenance of these systems prevents resin residue buildup, which could otherwise exacerbate odours, and ensures consistent performance in high-emission environments.
The implementation of ventilation systems not only reduces odours but also enhances workplace safety by minimizing worker exposure to harmful VOCs. For closed-mould processes like resin transfer moulding (RTM), sealing moulds tightly and integrating ventilation at demoulding stages further controls odour escape. These systems can be tailored to facility size, with smaller setups using standalone filtration units and larger plants opting for integrated HVAC solutions.
(ii) Use of Low-Styrene or Alternative Resins:
A proactive approach to odour control in GRP manufacturing involves selecting low-styrene or styrene-free resins to reduce VOC emissions at the source. Traditional polyester resins contain high styrene levels, contributing to strong odours and health risks. Low-styrene polyester resins or vinyl ester resins emit fewer VOCs during curing, significantly decreasing odour intensity. While these resins may increase material costs, they offer long-term benefits, including reduced odour complaints, improved worker safety, and alignment with environmental regulations.
The adoption of alternative resins requires careful consideration of application suitability, as vinyl ester or epoxy resins may have different mechanical properties or curing requirements compared to polyester. Manufacturers must evaluate these factors against the specific needs of GRP vessels, such as corrosion resistance for chemical storage. Pilot testing low-styrene resins can help assess performance without disrupting production. This strategy also supports sustainability goals by reducing the environmental impact of VOCs, making it appealing for facilities aiming to enhance their corporate social responsibility profile.
B. SMC Vessel Manufacturing
(i) Enclosed Mixing and Moulding Processes
SMC manufacturing involves pre-mixing chopped glass fibres with polyester resins and additives to create mouldable sheets, followed by compression moulding in closed systems, which inherently produces fewer odours than GRP’s open-mould processes. To control odours during mixing, enclosed systems with integrated ventilation or extraction units are essential. Automated mixing equipment minimizes styrene release by containing the process, while local exhaust ventilation captures any emissions during material handling. During compression moulding, closed moulds reduce odour escape, but residual styrene may be released when moulds are opened. Installing LEV systems near moulding machines ensures these emissions are captured and treated, maintaining a low-odour environment.
Enclosed processes offer significant advantages, including reduced worker exposure to VOCs and compliance with workplace safety regulations. For facilities producing high volumes of SMC components, such as small tanks or automotive parts, these systems enhance efficiency by streamlining odour control within the production line.
Additionally, Regular cleaning of mixing and moulding equipment prevents resin buildup, which could contribute to persistent odours.
(ii) Post-Curing and Off-Gassing Management
After moulding, SMC vessels may retain residual styrene, leading to odours during storage or use. Post-curing techniques, such as exposing moulded parts to controlled heat in a dedicated chamber, accelerate the off-gassing process, allowing VOCs to be released in a contained environment. This can be achieved using ovens or curing rooms equipped with ventilation systems that direct off-gassed air through and odour control unit (OCU). Alternatively, parts can be stored in well-ventilated off-gassing areas before finishing or packaging, reducing odour levels in the final product.
C. FRP Vessel Manufacturing
(i) Ventilation and Air Extraction Systems:
FRP vessel manufacturing, which includes GRP and other fibres like carbon or aramid, often involves open-mould processes that release significant styrene and other VOCs. Therefore, proper ventilation and air extraction is the key strategy.
(ii) Process Optimization and Enclosure:
Optimizing the manufacturing process for FRP vessels can significantly reduce odour emissions by minimizing solvent use, use of epoxy resins with milder odour and optimising curing times. Selecting faster-curing resins or adjusting formulations to lower styrene content decreases VOC release during production. Enclosing open-mould processes in booths or isolated areas equipped with exhaust systems allows for better control of odorous air, directing it through filtration units before release.
For closed-mould processes like filament winding or pultrusion, ensuring moulds are tightly sealed and equipped with integrated ventilation systems prevents odour escape during curing or demoulding, enhancing overall air quality management. Process enclosures offer dual benefits of odour control and improved production efficiency by reducing material waste and worker exposure to VOCs.
D. End-of-Pipe solutions or Advanced Filtration Systems
Effective odour control combines process optimization, engineering controls, and air treatment technologies. By combining enclosed systems with air treatment, manufacturers can achieve a cleaner workplace and minimize community complaints, particularly in urban settings where facilities are near residential areas.
Advanced air filtration systems are highly effective for removing these compounds from the exhausted air. These filters adsorb styrene and other organic molecules, achieving up to 99.5% reduction in odourous VOCs. Key advanced filtration strategies include:
Employing these systems can mitigate community complaints by preventing odourous emissions from escaping the facility, which is critical for plants located near residential areas. Another factor which is overlooked in many places are the employee training; Ensuring proper storage, mixing, and application techniques minimizes unnecessary emissions. Implementing these changes requires upfront investment in equipment and process redesign, but the resulting reduction in odour complaints, improved public relations and regulatory penalties offsets these costs and justify the investment. Regular process audits and air quality monitoring ensure that optimizations remain effective, allowing manufacturers to adapt to changing production demands or regulatory requirements while maintaining a low-odour environment.
Odour is not just an operational issue—it’s a community and compliance matter. Many jurisdictions have strict odour and VOC regulations. For example, styrene is a listed hazardous air pollutant (HAP) under U.S. EPA regulations. Manufacturers must monitor emissions and often report to local environmental authorities. In regions like the EU, occupational exposure limits (OELs) and industrial emissions directives (IED) govern VOC discharge. Facilities must demonstrate that Best Available Techniques (BAT) are being used for odour control.
Equally important is proactive communication with the community. Transparent environmental practices and prompt response to concerns build trust and social license to operate.
Elixir Enviro Systems Pvt Ltd (EES) offers specialized odour control solutions tailored to the unique challenges of FRP/GRP manufacturing facilities. Our services and technologies help reduce VOC emissions, improve workplace safety, and ensure regulatory compliance.
1. Design of Ventilation systems, Enclosure and Containment Solutions
2. Process Optimisation Consulting
3. On-site Services
4. Odour Control Equipment
5. Regulatory Compliance Support
Controlling odour in GRP, SMC, and FRP vessel manufacturing is not just a regulatory necessity—it’s a mark of modern, responsible manufacturing. By combining smarter material choices, better processes, and effective air treatment systems, companies can uphold product quality while protecting the environment and their communities. The result is a cleaner, more sustainable path forward for the composites industry. Partnering with Elixir Enviro Systems ensures access to industry-leading solutions for effective Odour management.