The challenge
Aquaculture is a rapidly growing sector that requires solutions to improve profitability and sustainability while reducing dependence on fishmeal and fish oil in feeds.
At the same time, the brewing industry generates around 8 million tonnes of organic-rich by-products each year. The challenge was to reduce the organic waste produced by the brewing sector while providing a sustainable and economically viable solution for feeding farmed fish.
The solution
In collaboration with the brewing sector, AZTI has developed an innovative process to valorise brewing by-products (spent grain and brewer’s yeast) for use as alternative raw materials in aquaculture feeds, in line with circular economy principles.
The scientific team evaluated their nutritional value, digestibility and effects on fish growth—in species such as rainbow trout—demonstrating that fishmeal can be partially replaced without compromising product quality, fish health or final taste.
The results
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Development of six new ingredients, four applicable to aquaculture feeds and two for nutraceutical uses.
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Valorisation of up to 75% of brewing by-products, significantly reducing industrial waste.
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Feeds containing 20% yeast, 15% spent grain and only 15% fishmeal, achieving growth performance comparable to commercial feeds.
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A tangible contribution to the sustainability and circularity of two key sectors: food and aquaculture.
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Demonstration of the potential of the bioeconomy as a driver of innovation and business competitiveness.