Effect of Blanching on Enzyme Activity and Quality Changes in Green Peas

Fresh green peas were blanched for various times/temperatures and stored at — 23°C. At 3 month intervals peas were analyzed for per‐oxidase, polyphenoloxidase, lipoxygenase and catalase activity and ascorbic acid content. Samples were cooked and evaluated sensorily, and using Hunter color and Instron texture measurements. Enzymes exhibited varying degrees of activity over the first 3 months in storage. After 3 months, peroxidase and polyphenoloxidase activity decreased or remained constant. Lipoxygenase activity increased over storage, most noticeably in the long time/low temperature blanch treatment. Sensory evaluation indicated a gradual loss of quality due to poor flavor in the long time/low temperature blanch. Ascorbic acid content, greenness and firmness decreased gradually with storage.