The study – published in LWT - Food Science and Technology – reports that fish protein isolated from inexpensive fish could provide a new basis for the incorporation of omega-3 polyunsaturated fatty acids into functional foods. The researchers, led by Jacek Jaczynski, an associate professor at West Virginia University, USA, demonstrated that is feasible "to develop functional food products made from muscle protein isolate recovered frrom whole gutted fish."
“Since the protein isolate in the present study is recovered from fish and used in a formulated food product, it is a logical vehicle for increasing the consumption of omega-3 PUFAs and concurrent reduction of sodium without the need for dietary supplements in a pill or capsule form,” explained Jaczynski and his colleagues.
The team produced the functional foods using fish protein combined with omega-3 fatty acids and a potassium chloride salt replacer. They found that the end product was “nutritionally enhanced with omega-3 PUFAs, had reduced sodium and increased potassium; while the colour and texture properties were good and gelation properties were improved.”
Jaczynski and his team said that although the results of their study “point toward the potential for novel, marketable functional food products developed from inexpensive sources”, further testing and refining of the sensory and stability properties of the products are still required.
Jaczynski explained that functional foods “are food products that contain added, technologically developed ingredients with specific health benefits.” The researchers noted that food products nutrified with omega-3 PUFAs “provide a means to achieve desired biochemical effects of these nutrients without the ingestion of dietary supplements, medications or a major change in dietary habits.”
In addition to the addition of omega-3 fatty acids, there has been some scientific support for the benefits of fish protein itself. A recent study published in the Journal of Functional Foods (reported here) found that protein from blue whiting fish could help to promote the production of gut hormones associated with suppressing appetite, and may aid weight management.
Fish protein isolate was used as a main ingredient in heat-set gels made with omega-3 PUFAs oils (flaxseed, algae, fish, krill, and blend) and potassium chloride (KCl)-based salt substitute.
“The overall objective of this study was to determine physicochemical properties of a functional food products developed with omega-3 PUFAs and salt substitute using muscle protein isolate recovered ... from whole gutted rainbow trout,” said the researchers.
The team reported that colour properties were improved in all cases apart from when krill or algae oil was added – whilst texture profile analysis “showed that omega-3 PUFAs generally did not affect texture of trout protein gels.”
They revealed that addition of omega-3 PUFAs oil also improved heat-induced protein gelation. Elastic modulus was found to increase when all omega-3 PUFAs except krill oil were added.
“The functional food products developed from fish protein isolate were nutritionally enhanced with omega-3 PUFAs, had reduced sodium and increased potassium; while the colour and texture properties were good and gelation properties were improved,” concluded Jaczynski and his team.
Source: LWT - Food Science and Technology
Volume 48, Issue 1, Pages 89–95, doi: 10.1016/j.lwt.2012.02.018
“Functional food products made from fish protein isolate recovered with isoelectric solubilization/precipitation”
Authors: R. Tahergorabi, S.K. Beamer, K.E. Matak, J. Jaczynski