Aquaculture is one of the fastest-growing sectors in food production. Due to the large volume of fish production, there is also a substantial generation of side-streams that are not used for consumer products. These aquaculture side-streams include backbones, belly flaps, fish fins, gills, heads, liver, roe, skin, viscera, and meat adhered to the bones. The same nutritional compounds present in fish products produced for human consumption are also available in these side-streams. Therefore, there is a need to analyze whether fish side-streams that are rich in bioactive compounds can be incorporated into novel food, feed, and other high-value products. This will benefit human health and contribute to the sector’s overall sustainability by using natural resources efficiently.

AQUABIOPRO-FIT partners, Centro Tecnológico de la Carne de Galicia and Universitat de Valencia, analysed the nutritional properties of gilthead sea bream side-streams. This fish species is one of the most important marine finfish species reared in Europe and is mainly produced in the Mediterranean and Northern European countries. This study characterized the nutritional value of several sea bream side-streams and compared it to the muscle, the most commonly marketed part of the fish.

More than half of the total wet weight of the processed gilthead sea bream is not used for consumer products and is considered side-streams. These side streams are rich in:

• protein (10%–25% of the total side stream)

• fat (17%–35% of the total side stream)

• high levels of essential amino acids (41%–49% of total amino acids)

• omega-3 fatty acids (about 13% of total fatty acids)

• macro and micro elements, especially i) calcium and phosphorous in head, fishbone, and gills ii) iron and zinc in liver.

The health properties associated with these bioactive compounds reveal that gilthead sea bream side-streams could be used as ingredients for value-added products such as protein, oils, and mineral supplements. Before these ingredients are incorporated in consumer products, more studies will need to be conducted to evaluate microbiological levels and safety. However, this research demonstrates the great potential of Gilthead sea bream side-streams as promising sources of valuable bioactive compounds and ingredients for the food industry.

Read the full article for more information: Pateiro et al (2020) Nutritional Profiling and the Value of Processing Side-Streams from Gilthead Sea Bream (Sparus aurata)