Various types of algae. (Photo: Portomuíños)
Experiments with algae to produce fish preservatives
Tuesday, December 11, 2012, 01:10 (GMT + 9)
Since 2009 the Cooperative of Shipowners of the Port of Vigo (ARVI) has been encouraging a project to offer the fresh trawling fleet of Gran Sol mechanisms to improve first-sale prices of their landings through a better preservation of its resources.
One of the companies that is working on this initiative is Portomuíños, from A Coruña, through the contribution of the necessary algae for the development of a special type of biodegradable plastic -- or preservative—to be applied on fish.
The project specifically focuses on two species captured by the trawling fleet: hake, which is very important for ships of A Coruña; megrim, which is vital for vessels from Vigo, La Opinión reported.
The preservative with which the study is being carried out is called Peixepac, and researchers estimate that a further year for experimentation is still needed.
The idea is to design biodegradable plastic films that include natural substances which function as preservatives to increase the shelf life of the product.
"To this end, substances having antimicrobial and antioxidant effect on fishery products should be included in the biodegradable plastic, polylactic here, in actual storage conditions on ships," explains Bibiana Garcia Soto, of the R+D area of ARVI.
In addition, there should be no transfer of these substances to the fish, as they may modify its taste, odour or colour, the researcher added.
The chosen algae are Bifurcaria bifurcata, Ascophylum nodosum, Ulva spp, Fucus spp and Gracilaria spp; although sorbic acid was also tested as preservative.
Portomuíños is a company specializing in marine flora for human consumption, which has already been involved in other projects driven by shipowners from Vigo.
The president of the firm, Antonio Muíños, highlighted the efforts made in the selection and processing of the product for this study, and predicted that the end result could be seen "in 2013, at the latest in 2014."
The University da Coruña collaborates with Portomuíños in the characterization of the algae and the study of the temporal and spatial distribution while the University of Santiago participates in Peixepac project with two groups: College of Pharmacy and of Veterinary.
The first set is analysing the response of the algae when being introduced into the biodegradable plastic matrix, its thermal stability and the active preservative components. The second group seeks to determine the antimicrobial properties of the chosen algae extracts and of the sheets developed in the project, with each chosen substance or algae.
In addition, the Institute of Marine Research (IIM) of the Scientific Research Higher Council (CSIC) is responsible for the assessment of the organoleptic degradation of algae and of the films as antioxidants and slowing down agents.
According to Garcia Soto, the results of the tests with fish are still being analyzed, so there are no definitive conclusions.
Anyway, he ensured that good results are being observed "at organoleptic level" for the films with Bifurcaria spp and sorbic acid, "both combined in one film."
"This combination allows the shelf life of the product to be risen, slowing the deterioration of hake without adding taste, odour or colour to the product," he concluded.
By Analia Murias