Agri-food waste is a largely untapped resource that aligns perfectly with the principles of the circular economy. Plant-based food production in particular generates by-products such as peel, seeds, bran, pomace and oil cake; fruit and vegetable processing generates 30–35% of this waste.
These materials are nutrient-rich and brimming with bioactive compounds such as proteins, vitamins, dietary fibres, flavonoids and phenolic compounds, many of which possess significant health-promoting properties.
Bioactives such as fibre in fruits help to improve digestion, flavonoids support heart health, curcumin (from turmeric) provides anti-inflammatory properties and peels from berries help to regulate blood sugar levels.
Scientific advancements have highlighted their potential to address chronic health issues such as diabetes, cancer, cardiovascular diseases and neurocognitive disorders, primarily because of their antioxidant and antimicrobial properties.
The idea of transforming waste into usable raw materials presents a number of sustainability opportunities to the nutraceutical sector.
Bioactives not only enhance the nutritional value of food but also improve its functional properties. For example, citrus-based terpenes can enhance both aroma and taste, polyphenols can act as a preservative and extend a product’s shelf-life, and berry derived anthocyanins provide a natural and appealing colour in foods.
The global nutraceutical market is valued at approximately $450 billion as of 2024 and is set to increase in the coming years. Hence, there is a great potential to use plant waste-derived bioactives in nutraceuticals to meet the increasing demand and growth of the market.
Plant-based bioactives: rising emergence
The global market for plant-based bioactives is experiencing remarkable growth; valued at $14–15 billion in 2024, projections indicate sustained expansion in near future. The sector has witnessed a surge in product launches featuring plant-derived extracts and bioactives.
Consumers prefer sustainably/naturally sourced and manufactured food with added nutritional benefits. To meet this demand, bioactive formulators continue to invest in natural and health-focused solutions.
For example, Designs for Health (US) has launched a plant-based supplement called Performance Peptides, which is made from fava beans and is designed to be used in antiageing supplements.
HealthTech BioActives (Spain) sells cardiose, an ingredient derived from sweet oranges using an extraction process. It contains polyphenols, which are powerful compounds known for benefits such as reducing inflammation, fighting bacteria and protecting the body with antioxidants.
Businesses have long been extracting bioactive compounds from plant-based sources such as fruits, vegetables and beans (soybeans and fava, for example). However, the industry has yet to begin extracting bioactive compounds from the waste products of these plant-based sources.
Currently, upcycled/waste material from the agri-food sector has not yet become a common source because the process of converting waste into valuable compounds is expensive … and only big companies are investing in or researching this.
For example, Cargill is using apple pomace to create pectin solutions; this ingredient works as a stabiliser and thickening agent. The company also uses citrus peels to make pectin.
The waste material left from food processing mostly ends up in landfills or is used in animal feed, which is of no use to innovators. However, if they start upcycling it to produce valuable bioactive compounds, it can promote a circular economy and generate new revenue streams.
Citrus waste processing is an excellent example of a circular economy and represents a well-established sustainable value chain. The peels from citrus fruits are used to extract pectin and essential oils such as lemon, orange and lime.
They contain limonene, which is useful in a variety of ways. As of 2024, limonene, which is extracted from citrus peels and has no synthetic substitute, is worth about $400 million.
Sources: where are these ingredients coming from?
Extensive research in the past few years has been conducted to demonstrate the value of food waste as a source of compounds with bioactivity or technological potential to introduce new, more sustainable and natural alternatives to the market.
The processing of food removes peels, stems, leaves and seeds, which are often rich in fibre, alkaloids and vitamins. Similarly, grain and cereal processing yields nutrient-rich by-products such as bran and germ, which contain protein, fibre and micronutrients.
Oilseed processing, after extracting the main oil, generates a meal or cake that’s rich in protein, polyphenols and residual oil.
For instance, one of the key ingredients in the Mediterranean diet is olive pomace, a by-product of the production of virgin olive oil, which has a polyphenolic profile similar to that of the oil but in higher concentrations per unit of weight.
One of the most reported potential sources is fruit and vegetable waste as it generates a large amount of residue in the food supply chain and is rich in different types of compounds that can be used for a variety of purposes.
In addition, the concentration of bioactive molecules is very high in agricultural waste (peels, leaves, seeds, flowers, fruits and vegetables that are not suitable for the market).
The waste, mainly the inedible parts of the vegetables, is generated during vegetable processing; most of it comes from harvesting. Potatoes, carrots and tomatoes are common vegetables used in the production of juices and canned goods. These vegetables are rich in phytonutrients.
Potato peel contains bioactives such as phenolic acids, glycoalkaloids and carotenoids, whereas discarded carrots contain tocopherol, carotenoids (beta-carotene, alpha-carotene and lutein) — at concentrations of approximately 1384 mg/kg.
Beta-carotene, worth approximately $350 million, is valued as a natural pigment and antioxidant used in supplements and fortified foods. Lutein is valued at $150 million in 2024 and is gaining popularity for use in eye health supplementation products.
The fruits with the highest concentrations of bioactive compounds in their by-products are berries, apples and citrus fruits. Approximately 50–60% of this waste is derived from citrus fruits such as oranges and lemons.
Citrus peel alone represents 15.6 million tons of waste annually. Citrus fruit peel contains bioactive substances such as polyphenols, essential oils, carotenoids and carbohydrates.
The seeds, which make up about 20–25% of the fruit but are discarded, contain limonoids, polyphenols and tocopherols — which are highly sought after in the food and pharmaceutical industries — and the pulp contains phenolic acids, flavones and flavanones.
Pomace, an apple waste product, contains bioactive compounds including carbohydrates, phenolic acids and flavonoids (at concentrations as high as 2153–3734 mg/kg); these are antioxidants, antimicrobials, anti-inflammatory agents and so on.
Between five and nine million tons of pomace, or leftover skins, seeds and stems, are produced by the grape industry, mostly through the production of wine and juice. Grape by-products are rich in bioactive compounds such as proanthocyanidins, anthocyanins, phenolic acids, stilbenes and flavonols.
Among all fruits, berries have the highest level of bioactive compounds. Blueberries, bilberries and cranberries, for example, are even referred to as “magical fruits” in the industry.
The anthocyanin content of berry waste, such as press residue, is high — ranging from 27,890 mg/kg for cranberries to 43,530 mg/kg for blueberries. It has the potential to be used for the prevention of chronic diseases.
Tip of the iceberg?
Fruit and vegetable by-products are not the only sources of bioactives; the cocoa and coffee industries produce a large number of them. Coffee grounds, husks and pulp are examples of waste that contain useful compounds such as proteins, caffeine, oils and carbohydrates including mannose, galactose, glucose and arabinose.
Approximately 85% of total cocoa production yields residual biomass such as pods, husks and pulp.
This can be used to extract valuable bioactive compounds such as polyphenols, pectin, phytosterols, dietary fibre and compounds with anti-inflammatory, antidiabetic, antihypertensive and anticholesterol properties.
If a business is spending money on the manufacturing process of turning these waste materials into new compounds, the source should be able to produce a sizable quantity of them and be extremely rich in bioactives.
And the most reliable and cost-effective source is fruit by-products, which produce nearly half the amount of waste as the actual product.
Thermal treatments and other traditional methods — such as extraction with potentially toxic organic solvents — are commonly used to recover high-value compounds from food waste and by-products.
In recent years, green technologies such as microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), supercritical fluid extraction (SFE) and other emerging approaches have advanced rapidly.
Unlike traditional methods, these technologies allow for faster processing, increased yield and higher quality extracted compounds.
What is happening in the industries?
Companies are experimenting with grape pomace, particularly what’s left over from the winemaking process, to develop nutritional products. Sonomaceuticals, a US-based company, has created a product called WellVine from Chardonnay grapes.
This product is said to improve gut health and glucose levels in the body. This ingredient is used in foods such as their premium Vine to Bar chocolate and is high in polyphenols and flavanols.
CrushDynamics (Canada) uses patented fermentation technology to transform agricultural by-products, including grape pomace, into bioactive food ingredients that are rich in antioxidants. Their natural process enhances polyphenols, boosting disease-fighting and food preservation properties.
Cargill has introduced LM pectin, a bioactive compound primarily found in citrus peels and apple pomace. The ingredient is intended for lower-sugar jams, bakery fillings and fruit spreads.
The company not only uses an upcycled source to make a useful ingredient, but also uses renewable energy and partners with a biomass plant for production.
Ocean Spray Ingredients (US) uses cranberry seeds that come from the company's fruit processing by-products to make food ingredients for baked goods. These seeds are rich in fibre, omega-3/omega-6 fatty acids and protein.
Conclusion
As the nutraceutical market continues to grow, driven by increasing consumer preference for plant-based bioactives, leading players such as Cargill, ADM, Kerry and dsm-firmenich have been actively innovating in this space.
These players are already launching novel upcycled products. To further advance the industry, these companies should explore utilising agri-waste as a sustainable source to extract bioactives, thereby transforming food waste into value-added nutraceuticals.
Research highlights the immense potential of food waste for this purpose, with numerous studies already demonstrating efficient methods for implementation. However, the absence of established regulations for agri-waste-derived bioactives remains a significant barrier.
It is time for manufacturers to overcome this challenge and lead the way to creating a more sustainable and circular nutraceutical industry.
Industry examples
- https://nutraceuticalbusinessreview.com/green-bioactives-nutra-bridge-distribution-partnership-gbl-memory.
- www.eurekalert.org/news-releases/1053462.