Titolo: Use of oil mill by-products to improve fish rearing in an aquaponic plant and to enhance some fishery products of reduced commercial interest. Food processing, quality, security and safety interactions.

Bando: PRIN

Durata: 24 mesi

Coordinatore: PROF. ENRICO NOVELLI

Budget BCA: € 99.167,00

Responsabile scientifico: prof. Enrico Novelli

Research Team: Novelli Enrico

Abstract: The composition of the diet used in aquaculture has important repercussions on the fish metabolism, on its body composition, on the aptitude for transformation into foods for human nutrition and their shelf life. In this research proposal one target it is the use a concentrate rich in hydroxytyrosol (an agricultural by-product from the Oil mill Vegetation Water, OVW) as an ingredient for the feed to be used for tench nutrition in the broodstock phase and tench in the fattening phase in an aquaponic system. Some experiments conducted in aquaculture have shown that the addition of phenols of different botanical origin to the diet of marine or freshwater fish causes a certain modulation of the lipid metabolism or of its immune status or inflammatory response to environmental stresses. OVW phenols has never been tested before in tench (Tinca tinca) ongrowing with the aim to improve the flesh quality and the reproductive performance. Both in vivo effects and growth, survival and yield performance will be measured. Part of the fish will be left intact and submitted to freshness evaluation, the large part will be processed into fillets and immediately subjected to rapid measurements by means of Near Infrared Spectrophotometry and Image Analysis. The main objectives of the research are: i) evaluation of the effect of the OVW phenols on immuno responce and broodstock performance of the fish during rearing, ii) evaluation of the effectiveness of rapid measurement systems (Nirs and IA) in predicting the most correct technological destination of the fresh fillet as well as the freshness variation during storage, iii) possible employment of the vegetable part (Ulva spp) of the aquaponic system as food product. At the same time, the research aims to bring new knowledge and insights on the in vivo effect of Hydroxytyrosol. The wide variety of its biological activities is largely associated with its strong antioxidant activity due to the presence of the o-dihydroxyphenyl fraction. The products collected within the aquaponic system (fish and Ulva) will be processed together with an olive patè to obtain an emulsified food product to be cooked and packaged. A significant part of the activities connected with the aquaponic plant will be dedicated to information and awareness-raising initiatives on the circular economy carried out through seminars with food business operators, public authorities, schools and consumers. Another target is the enhancement of some fishery products of reduced commercial interest but, at the same time, of good nutritional value with which is intended to obtain a ready-to-cook fish preparation to which an extract rich in phenols with high functional activity has been added. To mitigate some commercial problems limiting the use of some of these fish products (non-costant availability of fish on the market, for example), the technological quality of the product will also be tested after a suitable period of storage at freezing temperatures.