Dr. Marcin Rakowski is working as a Senior Scientist at National Institute of Marine. He has completed his specialization in maritime fishery and business related to impact of fishery on local economy at the National Marine Fisheries Research Institute. He is extending his valuable service as in fishery research allowing assessed multiplier effects of expenditure and revenue of fishermen in coastal region. His research interests reflect in his wide range of publications in various national and international journals.
Globalized seafood market changes the European traditional aquaculture production. One of the most exposed aquaculture sector in Central Europe is extensive regional fish farming especially of such species as carp, perch or pike. The extensive fish production has also lower competitiveness in relation to other imported or farmed fish products in Europe. It has also more technological problems with processing, fish bones, meat efficiency factor and discard factor. On the other side this sector produces still in sustainably and traditionally way. That tradition of carp consumption (especially during Christmas time) is one of the strongest attribute keeping this farming in Poland still in good economic condition. Neither, the grooving supply coming from global seafood markets degraded the position of domestic producers and changes the value chains. According to growing demand for cost-attractive and convinced product, carp farms are looking for effective strategies better adopting them to current market challenges. The survey of this problem has been undertaken in the EU project by acronym SUCCESS (“Strategic Use of Competitiveness towards Consolidating the Economic Sustainability of the European Seafood sector”). The project aims at establishing the synthetic competitiveness factors describing the fish and seafood species farmed and exploited in Europe. One of the searched sectors was traditional farming represented by carp. The method used in carp case studies was Agri Benchmark approach which focuses on typical farm surveys and typical behavior. The survey has been conducted at three farms in Poland representing typical farm sizes: 300, 150 and 20 hectares of water surface. The farm owners/managers were asked details about typical functional mechanisms used in operational, marketing, human resources and financial decisions. Identification of the mechanisms let the authors structure typical long term strategies in carp business and its economic efficiency. The most important variables affecting the strategies were: Farm size, position in value chain, productivity, distribution channels.
Chien-Hui Wu has his expertise in evaluation and development in function food material. Recently, his research were focusing on 2 ways, one is evaluating the metal-binding activity of collagen peptides from fish scale by enzyme digestion. On the other hand, the development of fermented food with gama-aminobutyric acid (GABA) by lactic acid bacteria isolated from aquatic animals. Now, he is teaching at the Department of Seafood Science, National Kaohsiung Marine University in Taiwan.
Thousands of tilapia fish scales are wasted without valuable utilization. Tilapia scale is rich in collagen that is hydrolyzed by enzyme digestion. The hydrolysate collagen peptides has antioxidant, anti-cancer, anti-anemia, immune regulation, anti-bacterial, hormonal regulation, inhibition of angiotensin transferase activity, prevention of arthritis, osteoporosis and other bioactive functions. Studies indicated that fish scale collagen protein hydrolysates has a well-binding capacity for calcium, iron, and copper, enhancing the biological activity of the fish scale collagen protein. The chromium content in human body significantly reduces as age increases. There have been studies indicated that trivalent chromium can regulate insulin function and maintain homeostasis of blood glucose, and improve the glucose tolerances of type II diabetes patients. Therefore, the aim of this study is to exploit the metal chelating ability of collagen hydrolysates by mixing low molecule weight fraction of collagen hydrolysates from tilapia scale with trivalent chromium (referred as C-Cr). The data showed that low molecule weight fraction of tilapia scale collagen hydrolysates can bind with 123 ppm trivalent chromium ions, forming collagen-organic chromium complex at pH 3 and 60°C maintained for 1 hr. Then addition of 50%, 100% and 200% of 750 mM chromium chloride to the collagen peptide hydrolysates was done respectively. The optimized condition was when 100% 750 mM chromium chloride was added to collagen peptide hydrolysates which can bind to 175 ppm chromium ions. In the feature, we hope to develop a functional food material with hypoglycemic activity by C-Cr components.