Preparation and Storage of Pinnatu Destroys the Hypocholesterolaemic Effect of Palmyrah Fruit Pulp

Abstract

It has been suggested that the hypocholesterolaemic effect of palmyrah fruit pulp (PFP) is brought about by the soluble dietary fibre which is dominated by pectin, However, this has not been conclusively proven. The present publication describes studies to determine if pinnatu (dried PFP, fruit leather) could possess any hypocholesterolaemic activity. Neither pinnatu (prepared by drying PFP in layers as in the conventional method) nor pectin extracted from pinnatu (incorporated at a double dose to above experiment) could indicate any hypocholesterolaemic effect on normal Wistar rats. Pinnatu pectin on separation on Sepharose gel chromatography showed a high elution volume pattern indicating the hydrolysis of pectin while processing. Further it was found that pinnatu contains exopectinase activity. Subsequently, pinnatu was prepared using a modified method in order to minimize the hydrolysis of high molecular weight pectin. The Sepharose gel chromatography pattern of the isolated pectin of the modified pinnatu showed no degradation of pectin. However, after storing (6-7 months), this pinnatu pectin showed a slight shift to the lower elution volume indicating slight hydrolysis. On feeding Wi star rats with this pinnatu showed no hypocholesterolaemic effect (p=O.85). It is concluded that the preparation and storage of pinnatu destroys the hypocholesterolaemic effect of PFP. High molecular weight pectin may not be the major factor: for the hypocholesteroJaemic effect ofPFP. It is also possible that storage of pinnatu causes not only chemical but also physical changes in pectin.