Lignin Formation and Surface Discoloration of Minimally Processed Carrot Sticks

The effects of an ethylene absorbent and storage at 2°C on surface discoloration and phenolic changes in modified atmosphere packaged carrot sticks was studied. Lignin formation occurred and corresponded with development of white discoloration in storage. Phenylalanine ammonialyase and peroxidase activity were stimulated by slicing and both enzyme activities remained elevated during storage. Soluble phenolics increased during storage, while dry matter content decreased within 24 hr after processing and then remained constant during storage. Ethylene absorbents prevented accumulation of ethylene, but did not affect surface discoloration or lignification.