1. Field of the Invention
The present invention relates to the inactivation of undesirable enzymes.
2. The Prior Art
It is well known that certain enzymes in food products contribute to their spoilage during storage over long periods of time.
The traditional method to inactivate these undesirable enzymes is to expose the food product to elevated temperatures which will normally destroy such enzymes. The application of heat, however, has a deleterious effect on the quality, feel or "freshness" of the food product. Thus, the elevated temperatures are not specific to enzymes but also degrade other components of the food which contribute to desirable qualities in the food product.
It has been reported in the literature [Owusu-Yaw et al, J. Food Sci., Vol. 53 (2), pp. 504-507 (1988); reported in abstract form at IFT Annual Meeting, Jun. 16-19, 1987] that the enzyme, pectinesterase (PE) can be irreversibly inactivated after addition to orange juice by lowering the pH of the juice product. This is achieved by the addition of hydrochloric acid or ion exchange resin. The addition of chemicals, however, to food products is viewed by the general public as undesirable and there exist many regulations governing the addition of such chemicals to foods. The use of ion exchange resins suffers from the additional disadvantage that it removes or destroys many flavor attributes of the food product viewed as desirable by the consumer.
It is an object of the present invention to provide a system for inactivating deleterious enzymes in foods which reduces or eliminates the above-noted disadvantages.