PRESERVATION OF NATURAL STABILITY OF FRUIT "BROMELAIN" FROM ANANAS COMOSUS (PINEAPPLE)

Pineapple extract, "bromelain," is a rich source of proteases having therapeutic benefits. The processed fruit does not show proteolytic activity probably due to harsh conditions of sterilization. Storage of fresh fruit at -4C without preservatives retained 75 +/- 5% proteolytic activity after 180 days (with or without eight cycles of freeze-thawing in between) and was devoid of microbial contamination. Peroxidase, acid phosphatase and amylase activities were also retained by 75 +/- 5%. Immunomodulatory activity of the fresh and the stored fruit was comparable. For industrial scale, gamma irradiation of 1-2 kGray is proposed to ensure sterility that does not affect enzyme activities. Under these conditions, no signs of freeze burning are observed. The ultraviolet-visible spectra of the fresh and stored fruit extracts are also indistinguishable. The process is commercially viable and amply improves the quality of processed pineapple in terms of active "bromelain.".