Residual effect of CO2 on hake (Merluccius merluccius L) as a function of the period of time in controlled atmosphere storage

Whole gutted hake kept in a controlled atmosphere (60% CO 2 /15% O 2 /25% N 2 ) for 7 and 12 days in containers in the hold of the fishing vessel and then stored conventionally in ice was compared with hake stored in ice and treated in the traditional way. The residual effect of the atmosphere containing CO 2 prolonged the shelf-life of chilled hake by 2-5 days compared with that of hake stored in ice. This residual effect of CO 2 was dependent on the period of time in the controlled atmosphere; 12 days in this atmosphere was the optimum to obtain the maximum residual effect of CO 2 . On day 25 the legal limit of total volatile basic nitrogen (TVBN) was reached in hake previously kept under the controlled atmosphere for 12 days (CA12), and the hake was also rejected in the inspection and pH analyses. However, this lot did not reach the legal limit of trimethylamine nitrogen (TMA-N) during the 25 days of storage. Similar results were found by a sensory panel, who rated the hake kept in controlled atmosphere storage (CA12) well. Les atmospheres controlees seraient tres utiles a bord des bâteaux de peche lors de sorties en mer de 15-20 jours, pour prolonger la duree de conservation des poissons. Le sujet de cette etude est d'examiner l'effet residuel du CO 2 sur le merlu entier eviscere, entrepose dans la glace et traite par les voies traditionnelles en comparaison avec le merlu conserve a bord d'un bâteau pendant 7 a 12 jours sous atmosphere controlee (60% CO 2 , 15% O 2 , 25% N 2 ) et dans la glace. Ce traitement est efficace et economiquement viable pour des durees d'entreposage superieures a 16 jours.