Copyright 2010 Accademia dei Georgofili
Si sono affrontati i problemi presentati dall’uso delle farine di pesce nelle produzioni ittiche biologiche. Sono stati studiati gli effetti di alcuni antiossidanti naturali come potenziali sostituti di quelli di sintesi. Gli estratti acquosi delle foglie di nocciolo e di vinacce e vinaccioli insieme all’olio di rosmarino sono quelli con maggiore potere antiossidante. L’olio di rosmarino è stato anche sperimentato con risultati positivi nell’alimentazione di spigole.
The results of the research highlighted two bottleneck of the organic food chain of the production of organic feed for fish farming: the supplying of fish meal and fish oil, and the natural antioxidants. A possible solution of the reduction of the use of fish meal and oil could be represented by the by product of fillet production and by trash or undersized fish from fisheries. This kind of material is a god source of nutrients, both of protein and of lipids, but with some constrains: chemical composition variability, collection and transportation to the processing companies in order to obtain meals suitable to animal feeding. The effects of some natural anti-oxidants in the substitution of chemical origin ones were considered with a study of a selection of plant extracts. Aqueous extracts of the leaves of hazelnuts, grape seeds, tomato peels and seeds and the oils of rosemary, of olive vegetation water showed antioxidant activity determined by means of DPPH% and TBARs. The oil of rosemary has been also tested with positive results in feeding sea bass in a long farming trial.
