Pre-cut fruits and vegetables constitute a fast growing sector of the food industry. Upon being cut, however, fruits and vegetables rapidly undergo an enzymatic browning process which detrimentally affects their quality. Polyphenol oxidases play a major role in this phenomenon as they generate o-quinones which subsequently polymerize to form brown pigments. Although a number of chemical compounds have being used to inhibit these enzymes, natural alternatives are highly desirable.

Kurt Schulach, University of Florida, USA, and colleagues discovered that blue mussels (Mytilus edulis) extracts efficiently inhibit a broad range of polyphenol oxidases. By further characterizing and purifying the mollusks extracts, the researchers attributed the inhibitory activity to the sulfinic acid hypotaurine (C₂H₇NO₂S, pictured). This compound may, thus, represent a novel natural strategy to prevent the enzymatic browning of fruits and vegetables.

• Polyphenol oxidase inhibitor from blue mussel (Mytilus edulis) extract,
  K. F. Schulbach, J. V. Johnson, A. H. Simonne, J. Kim, Y. Jeong, Y. Yagiz, M. R. Marshall,
  J. Food Sci. 2013.
  DOI: 10.1111/1750-3841.12059