Pectic applications

Pectinases are the enzyme that widely used especially in industrial applications (1, 2, 3, 4). Types of the pectinases are different concerned on their properties and the actions on the pectic substances (5). Several genus of fungi could produce pectinases eg. AspergUlus, PeniciUium, Sclerotium, Fusarium and Rhizopus (6,7). 

VII. Role and Application op Pectic Enzymes 1. In Undisturbed Plant Tissue... 

NBt Reynolds number, dimensionless, taken as DVp/n and DVp/t) for Newtonian and Bingham-plastic fluids respectively. The generalized Reynolds number Dn V2 n p/y is applicable to all except thixotropic and rheo-pectic fluids... 

Pectinases These enzymes carry out the hydrolytic degradation of the D-glycosidic linkage in pectins. The latter substances, also known as pectic substances, are polymeric components of plant cell walls and. like starch, are composed of sugar residues linked by glycosidic bonds. The chemistry is the same as that shown for the amylases previously described. The main application of pectinases is in the production of fruit juices, wines, and certain other food products. 

The classification of pectic enzymes in general, their occurrence in higher plants and micro-organisms and the properties of pectic enzymes from some plants and food grade micro-organisms are described with special emphasis on their substrate specificity. Their technological roles and applications, also in combination with (hemi-)cellulases, in a variety of processes are discussed. Evidence is presented for the existence of a new type of pectic enzyme which acts specifically in the hairy regions of pectic substances. 

Table III. Technological roles and applications of pectic enzymes...

More knowledge of physical and chemical properties of pectic enzymes, their substrate specificity, pattern of action, action on plant tissues, interaction with each other and other polysaccharide degrading enzymes is essential to establish their technological roles and to improve existing applications and to develop new applications. 

The present review indicates that while pectin products continue to serve as a well-established food additive for technological purposes, the application of pectins for health benefits has many potential opportunities. In the last few decades, considerable research has been done on the physiological effects of pectin in humans as a water-soluble dietary fiber supplement. Some novel pharmacological activities of pectins and pectic polysaccharides are gaining more attention. Although most natural pectins from fruits and vegetables have not been shown to have these activities, chemical and enzymatic modifications may provide useful tools for producing such products for human health care. 

Olive pomace dry matter produced by the two-phase system is a source of arabinan-rich pectic polysaccharides that should be exploited. They contain a diagnostic terminally-linked p-(l—>5)-arabinose residue in the a-linked backbone they are able to form elastic gels with calcium, which present syneresis for high calcium concentration and are more resistant to high temperature than commercially available low-methoxyl pectin/calcium gels. These properties make them valuable as food ingredients for specific applications. 

---