Suchergebnisse

The market value of crustaceans depreciates during storage due to the appearance of melanosis caused by polyphenol oxidases. Sulfite derivatives are used as melanosis-inhibiting agents, but their unhealthy effects make it preferable to replace them with natural preservatives. In this work, a crude enzymatic extract from whiteleg shrimp (Penaeus vannamei) was characterized and used to test the diphenol oxidase-inhibiting activity of polyphenol extracts of five underutilized halophyte plants, namely crystalline ice plant, seaside arrowgrass, purslane, sea fennel, and seashore aster. The extracts inhibited diphenol oxidase activity more efficiently than sodium sulfite. The purslane extract was rich in isoorientins, isovitexin, and apigenin, and showed the highest inhibiting effect, being this classified as mixed or non-competitive. Hydroxyl groups in the phenyl B ring could be responsible for the inhibitory activity of the extract. The polyphenol extracts tested in this work could be promising melanosis-inhibiting agents of interest for seafood industries. ; This work was supported by the Spanish Ministry of Economy and Competitiveness project (grant number AGL2014-52825-R) and cofounded with European Union ERDF funds (European Regional Development Fund). Author A. Tzamourani was funded by the Erasmus Program. ; Peer reviewed

Challenge F. ; International migration is a highly complex and global phenomenon, an ideologically charged and polarizing topic of enormous symbolic and political relevance, a phenomenon that requires an interdisciplinary approach from both a descriptive as well as normative perspective. Migratory flows have increased and are incrementally caused by armed conflicts or climate change, as well as by acute global inequalities. Given that the causes and implications of migration exceeds state limits acomprehensive study needs to abandon "methodological nationalism". The economic and social integration of the migrant population is a complex challenge, but the opportunities it opens up are also manifold: migration drives economic growth, connects different cultures, and contributes to international development. ; Peer reviewed

Salted cod is a product highly appreciated by consumers, especially in Southern Europe and Latin America. In recent years there has been increasing consumer demand for products with low sodium content, and this has led the salting industry to seek new salt mixtures to help to reduce Na+ levels without producing alterations in the properties of the final product. In this study, Atlantic cod (Gadus morhua) was initially brined with various mixtures of salts based on NaCl, at various pH levels and including KCl, MgCl2 and/or CaCl2. After subsequent dry salting with NaCl, the Na+, K+, Ca2+ and Mg2+ cation contents were evaluated, and also their effect on water loss, salt uptake, entry of chloride, water holding capacity (WHC), water extractable protein (WEP) and hardness of the end product. A greater presence of K+ in muscle was associated with greater water loss, salt uptake and hardness of the dry salted product. Moreover, incorporation of Ca2+ and Mg2+ negatively affected water holding capacity. These changes were not dependent on brine pH and might significantly alter the acceptability of the final product. © 2013 Elsevier Ltd. ; This research was supported by the European Union under project FAIR-CRAFT CT 98-9109. ; Peer Reviewed

Eight seafood protein hydrolysates (SPHs) obtained from squid, shrimp and fish gelatin were incorporated as substitutes of peptones in culture media in order to evaluate its effect on survival and metabolic activity (lactic acid, acetic acid and bacteriocins production) of Enterococcus faecalis DM19. The substitution of commercial peptones in culture media by either a shrimp hydrolysate prepared with Protamex, or by squid protein hydrolysates prepared with Esperase or Alkaline protease, stimulated E. faecalis DM19 growth up to 16%. The incorporation of SPHs, mainly from shrimp, in the culture media significantly increased production of lactic and acetic acids in more than 60%. Furthermore, the media containing SPHs stimulated antimicrobial activity by E. faecalis DM19. The inhibitory activity was observed against both Gram-positive and Gram-negative microorganisms, but it was remarkably observed against Listeria monocytogenes. SPHs incorporated in culture media render properties of bio-technological interest, which, together with their low price, make them suitable for industrial use. ; This research was financed by the Spanish Ministry of Economy and Competitiveness (projects AGL2011-27607, AGL2014-52825-R). Author M. Djellouli is funded by The National Centre of Biotechnology Research (CHER-Stage 06-2013) (CNRBt) of Algeria and ENP (Exceptional National Program) Scholarship provided by the Ministry of Higher Education and Scientific Research of Algeria (099/PNE/ENS./ESPAGNE/2015-2016). Author M. Arancibia is funded by a SENESCYT Scholarship (20100338) provided by the Ecuadorian government. ; Peer Reviewed

The recent interest in diversification in food consumption and the current salinization and desertification processes of farmland have placed the focus on halophytic plants as new food, making necessary the characterization of their biochemical composition and the identification of possible bioactive compounds. In this work, three edible halophytic plants were characterized: common iceplant (Mesembryanthemum crystallinum), sea fennel (Crithmum maritimum), and seaside arrowgrass (Triglochin maritima). The plants studied were a good source of minerals. Sea fennel showed high contents of dietary fibre and calcium (8.5 ppm, wet weight), common iceplant had a high potassium content (6500 ppm, wet weight), while seaside arrowgrass presented high levels of iron (62 ppm, wet weight). The glucose content of the three species was below 30 mg/g per dried weight. The Sb, Pb, Cr, As, Cd, and Hg content was negligible. Polyunsaturated fatty acids, mainly α-linolenic and linoleic acid, prevailed in the three species analyzed. Hydroxycinnamic and hydroxybenzoic acids predominated in common iceplant and sea fennel. Glycosylated flavones, especially isoorientin, prevailed in seaside arrowgrass. These plants present a relevant nutritional profile for which their use as foods or ingredients should be promoted. ; This work was supported by the Spanish Ministry of Economy and Competitiveness project under Grant (number AGL2014-52825-R) and cofounded with European Union ERDF funds (European Regional Development Fund). Author Sánchez-Faure was also funded by the Spanish Ministry of Economy and Competitiveness (fellowship number BES-2015-074420). ; Peer reviewed