The effects of modified atmospheres, edible coating and storage temperatures on the sensory quality of carrot discs

Packaging within a microperforated oriented polypropylene (OPP) film PA-60 generated useful modified atmospheres (MAs), which resulted in retention of good textural, aroma and flavour characteristics, but allowed surface whitening and a loss of headspace aroma volatiles to occur. By contrast, plain OPP film generated anaerobic atmospheres that resulted in an overall poor sensory quality with tissue softening and excess surface moisture, a loss of aroma acceptability and production of ethanol. Use of an edible coating (Natureseal) treatment had beneficial effects on visual quality. It significantly improved sensory scores, which appeared to be caused by a reduction in surface whitening and moisture loss. Increasing storage temperature from 4 to 8 degrees C resulted in a shorter shelf-life in both films. Principal component analysis showed that MAs had the biggest influence on quality, but Natureseal treatment could further help extend shelf-life. Of the packaging films examined, PA-60 film was better at maintaining the sensory quality. However, the additional use of a Natureseal treatment and storage at 4 degrees C was most effective in extending shelf-life.