Assessment of can quality concerning interactions with canned food.

Today sonsory evaluations will be taken as criteria for shelf-life estimations of canned food. Product specific quality changes have to be considered first. Limitations of the shelf-life by interaction with package material depend on several factors as food sensitivities and package specific properties. Concerning metal cans the extend of interactions has been reducted to a low level by the progress in can manufacturing. The package specific shelf-life of inside protected welded cans can be evaluated. The importance of the bottom/seam porosity (BSP) as a can quality parameter and the influencing factors are outlined with reference to the results of medium and long term storage tests. Special emphasis is given to the use of electrochemical impedance spectrometry (EIS) for testing. An AC/DC combination method for rapid quality assessments of metal/lacquer interfaces is proposed. EIS is able to give information about corrosion mechanisms, product compatibility and stresses during steriliz ation processes.