Rethinking Pet food Sustainability: Upcycled and Rendered Ingredients as Strategic Tools for People, Pets and Planet

For pet food manufacturers, environmental goals cannot be treated separately from nutrition, cost, palatability, safety, or processing performance. A formulation may look attractive from an environmental perspective, but if it compromises digestibility, animal acceptance, manufacturing efficiency, supply reliability, or affordability, it will struggle in the marketplace. The challenge is to reduce environmental impact while maintaining product performance and profitability.

Ultimately, sustainable pet food must balance the needs of people, pets, and planet—providing safe and nutritious diets for companion animals while making responsible use of natural resources and supporting economically viable food systems. This aligns with the broader concept of nutritional sustainability, which considers nutrient adequacy together with ecological, social, and economic dimensions of the food system (Swanson et al., 2013).

Upcycled and rendered ingredients deserve renewed attention because they support waste reduction, nutrient recovery, resource efficiency, and the economic realities of pet food production.

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Reframing the Word 'Byproduct'

One of the main barriers to broader acceptance of rendered and upcycled ingredients is not only technical, but linguistic. Terms such as 'byproduct,' 'meal,' or 'rendered' may be misunderstood by consumers, even when the ingredients are safe, nutritious, and functional.

A byproduct is not, by definition, a poor-quality material. AAFCO defines byproducts as secondary products produced in addition to the principal product (AAFCO, n.d.). In pet food, many byproducts originate from the human food system. They may include organ meats, bones, fats, connective tissue, trimmed material, or other nutrient-rich fractions that are not commonly consumed by people in certain markets but still contain valuable protein, fat, minerals, and functional compounds.

This distinction is important. Dogs and cats do not require ingredients because they sound appealing to humans; they require nutrients. Protein, amino acids, essential fatty acids, minerals, vitamins, and energy can be supplied through many ingredient streams. The role of the formulator is to evaluate these materials based on nutritional contribution, safety, digestibility, consistency, and suitability for the intended product.

At the same time, consumer perception matters. Rendered ingredients remain widely used across the industry, but in premium and super premium segments, many consumers associate fresh meat, named meats, or meat as the first ingredient with higher quality. This does not make rendered ingredients less valuable, but it does require more careful positioning. The industry's task is to communicate how different ingredient streams contribute to nutrition, sustainability, affordability, and performance without ignoring the expectations that shape purchasing decisions.

Upcycled, Rendered, and Circular Nutrition

In sustainability discussions, the terms 'upcycled,' 'rendered,' and 'circular' are sometimes used interchangeably. They are related, but they are not identical.
 

• Upcycled ingredients represent the broader concept. The Upcycled Food Association defines upcycled foods as using ingredients that otherwise would not have gone to human consumption, produced through verifiable supply chains, and having a positive environmental impact (Upcycled Food Association, n.d.). In pet food, this may include side streams from food processing, agriculture, fermentation, cereal milling, oilseed processing, fruit and vegetable production, seafood processing, dairy processing, and animal protein production. Their value lies in redirecting usable nutrients away from waste or lower-value applications and into safe, useful products.
   
• Rendered ingredients are more specific. Rendering is the process of reclaiming animal-derived materials, such as meat, bone, and fat and transforming them into stable fats and proteins that can be used in feed, pet food, biofuels, and other applications (North American Renderers Association, n.d.). In pet food, rendered ingredients may include poultry meals, meat and bone meals, animal fat, poultry fat, palatants, and specialty protein meals. These materials are often derived from parts of animals that are not commonly consumed by people in a given market but remain rich in protein, fat, minerals, and other nutrients.
  
  Therefore, rendered ingredients can fit within an upcycled or circular nutrition strategy when they recover nutrients from the human food and livestock systems. However, not all upcycled ingredients are rendered. Upcycled materials may also include brewer's grains, fruit pomace, vegetable fibers, oilseed meals, fermentation co-products, marine trimmings, and other nutrient-rich streams.
   
  
• Circular nutrition is the broader framework that connects both categories. The circular economy is based on eliminating waste, circulating products and materials at their highest value, and regenerating natural systems (Ellen MacArthur Foundation, n.d.). Applied to pet food, circular nutrition can be understood as the intentional use of safe, nutrient-containing streams from existing food and agricultural systems to reduce waste, improve resource efficiency, and deliver nutritional value. Under this framework, upcycled and rendered ingredients are not second-tier alternatives. They are strategic tools for designing pet foods that support people, pets, and planet.
  

Sustainability Must Be Paired with Performance

The environmental value of upcycled and rendered ingredients is strongest when it is paired with nutritional and commercial performance. A responsible ingredient must still be delivered in formulation, processing, and feeding.

For rendered meals and upcycled protein sources, this means evaluating amino acid profiles, digestibility, ash level, mineral balance, fat quality, freshness, palatability, processing compatibility, cost-in-use, and supply reliability. For fats and oils, it means understanding energy density, fatty acid profile, oxidative stability, and palatability contribution. For hydrolysates and specialty fractions, it means considering peptide profile, functional positioning, solubility, taste, and claims support.

The goal is not to replace performance with sustainability. It is to identify ingredients where both reinforce each other. Rendered and upcycled ingredients can support that balance because they often provide concentrated nutrients, established supply chains, favorable cost structures, and strong formulation utility.

This also connects to nutritional sustainability. A sustainable pet food system must provide adequate, safe, and effective nutrition while balancing environmental, social, and economic considerations. In practical terms, sustainability is shaped by what ingredients are selected, how efficiently nutrients are delivered, how well the diet is digested, and how much food the pet ultimately consumes (Swanson et al., 2013).

Five Strategies for Rethinking Petfood Sustainability
First, formulate for nutrient delivery while recognizing market position. Ingredients should be evaluated by what they deliver nutritionally and functionally. At the same time, premium and super premium products must also address consumer expectations around ingredient identity, label presentation, and perceived value. The opportunity is to combine both disciplines: sound formulation and substantiated market positioning.

Second, use various sources of protein. No single protein source needs to carry the entire nutritional, sustainability, and marketing burden of a product. Rendered proteins can be combined with fresh or frozen meats, plant proteins, yeast proteins, marine ingredients, hydrolysates, insect proteins, or single-cell proteins to optimize amino acid balance, cost, palatability, label appeal, and environmental profile.

Third, measure quality more precisely. Crude protein and crude fat are useful starting points, but they are not enough. Better evaluation should include amino acid profile, protein digestibility, fat quality, peroxide value, anisidine value, free fatty acids, ash and mineral balance, microbiological quality, and palatability response. This is especially important for rendered ingredients, where freshness, processing control, and raw material handling can significantly influence performance.

Fourth, build sustainability into procurement. Ingredient sourcing should include documentation of traceability, food safety systems, rendering controls, supplier quality programs, energy efficiency, and environmental reporting. Sustainability should be part of supplier selection, specification development, and quality assurance—not only a marketing claim after formulation is complete.

Fifth, communicate circular nutrition carefully. Consumers may be interested in sustainability, but they are also sensitive to language. Overclaiming can damage trust. A better approach is to explain that upcycled and rendered ingredients help recover nutrients from existing food systems, reduce waste, support efficient use of resources, and contribute to complete and balanced nutrition.

Measuring Footprint and Formulation Value

The next stage of pet food sustainability will require better measurement. Carbon footprint, water use, land use, ingredient scarcity, transportation distance, digestibility, and nutrient density may all become part of more advanced formulation decisions. Life-cycle assessment tools and supplier-specific data can help companies compare options more accurately.

However, rendered and upcycled ingredients require thoughtful assessment because many are co-products of existing systems. Their environmental value is tied to allocation methodology and to the fact that they recover nutrients that might otherwise be discarded, composted, landfilled, or used in lower-value applications. Simple comparisons between 'animal' and 'plant' ingredients may miss this nuance.

The industry needs tools that consider not only environmental impact per kilogram of ingredient, but also environmental impact per unit of digestible nutrient delivered. This is especially relevant for proteins, fats, and mineral-rich ingredients. A low-impact material that contributes little usable nutrition may not be as sustainable as a more nutrient-dense option that supports efficient formulation and feeding.

Rethinking Protein and Rethinking Value

The future of sustainable pet food will not be built only on novel ingredients. Innovation will continue through new proteins, fermentation-derived ingredients, precision nutrition, and improved packaging. But it will also depend on making smarter use of nutrient streams that already exist.

Upcycled and rendered ingredients offer a bridge between environmental responsibility, pet nutrition, affordability, and manufacturing performance. They can help reduce waste, support circular nutrition, and maintain the nutritional quality and economic viability required by the market.

In that sense, rethinking protein also means rethinking value. The question is not only where protein comes from, but how completely, responsibly, and intelligently we use it. For the pet food industry, that may be one of the most important sustainability opportunities ahead.

By Juan Gomez-Basauri, Ph.D. - MAGELLAN LLC
Source: All Pet Food Magazine

References
AAFCO n.d. 'Byproducts.' Accessed June 17, 2026 (https://www.aafco.org/consumers/understanding-pet-food/byproducts/) 
Ellen MacArthur Foundation. n.d. "Circular Economy Introduction." Accessed June 17, 2026. https://www.ellenmacarthurfoundation.org/topics/circular-economy-introduction/overview.
Kelly S. Swanson, Rebecca A. Carter, Tracy P. Yount, Jan Aretz, Preston R. Buff. Nutritional Sustainability of Pet Foods. Advances in Nutrition. Volume 4, Issue 2, 2013. Pages 141-150, https://doi.org/10.3945/an.112.003335
North American Renderers Association. n.d. "Animal Rendering - What Is Rendering." Accessed June 17, 2026. https://nara.org/what-is-rendering/.
Upcycled Food Association. 2020. "About Upcycled Food." Accessed June 17, 2026. https://www.upcycledfood.org/upcycled-food.