Synergetic effect of microwave blanching and modified atmosphere packaging using laser micro-perforated bags on the storage quality of carrot

The present study was undertaken to determine the combined effffect of microwave blanching and micro-perforated modifified atmosphere packaging in maximizing shelf life on the basis of quality attributes which were evaluated during storage. The carrots were blanched in water using a microwave at 360 W and then stored in micro-perforated modifified atmosphere packaging. The results indicated that blanched carrots in micro-perforated modifified atmosphere packaging showed an improved storage quality. In particular, it was observed that the fifirmness of the pretreated samples in the micro-perforated package were signifificantly improved. The enzyme activity (peroxidase) initially increased and then decreased with longer storage times. There was also a greater reduction in water content in sample C8, probably due to a higher rate of evaporation through the perforations. Water mobility which comprises tightly bound water, loosely bound water, and immobilized water were observed in all samples, while the free water level was insignificant in pretreated micro-perforated samples. The free water, T24 peak was observed for the control sample which increased with increase in storage duration. Also, the effects of this preservation method on other quality parameters such as β-carotene, water activity, moisture content, and microbial load was limited. However, sample C8 was more effective in retaining quality. Overall, this study demonstrated that blanching carrot in micro-perforated MAP at C8 was the most useful technique in preserving the storage qualities of carrot