Free Access
Issue |
Lait
Volume 80, Number 1, January-February 2000
New applications of membrane technology in the dairy industry
|
|
---|---|---|
Page(s) | 139 - 153 | |
DOI | https://doi.org/10.1051/lait:2000101 |
DOI: 10.1051/lait:2000101
Lait 80 (2000) 139-153
Implementation of integrated membrane processes for pilot scale development of fractionated milk components
Philip M. Kelly, James Kelly, Raj Mehra, David J. Oldfield,
Elaine Raggett, Brendan T. O'Kennedy
Dairy Products Research Centre, Teagasc, Fermoy, Co. Cork, Ireland
Abstract:
Numerous opportunities for the separation and fractionation of milk and whey components are presented as a
result of continuing developments in filtration membranes modules and processes. The preparation of
sufficient quantities of selected protein groups for functionality studies and food application tests
requires considerable amounts of starting material, particularly in the case of whey-based constituents.
Adequate amounts of membrane filtration surface area are, therefore, needed in order to expedite
processing time, limit conditions for microbial growth and increase productivity from a product
development point of view. With this objective in mind, a series of large pilot plant membrane separation
systems based on microfiltration, ultrafiltration and electrodialysis were recently installed and
commissioned. Rapid ultrafiltration of whey for the generation of high protein concentrates under a wide
variety of conditions, including `cold' filtration, is facilitated by a Memtech
spiral wound
membrane plant with a maximum surface area of 144 m2 that is accommodated within 3 modules mounted in
parallel. Designed to operate on a continuous feed-and-bleed principle, product is heated while pumping
via a plate-heater to the plant's balance tank in order to raise temperature to the desired operating
condition. Magnetic flow meters mounted on the feed, permeate and diafiltration water lines enable the
volume concentration ratio to be controlled throughout a run. Defatting of rennet whey by microfiltration
using a Tetra Pak Alcross,
Type
Special, crossflow microfiltration (MF) plant
fitted with a m pore size ceramic membrane with a filtration area of 13.3 m2 trebled flux rate
during ultrafiltration at C under steady state conditions. High protein whey protein
concentrates (ca. 80% total protein) were processed in the defatted and non-defatted state at either
C or C for functional characterisation. Preliminary analyses indicate that all
4 WPC's produced weak gels. Native phosphocasein was prepared from skim milk using the above MF plant.
Partial demineralisation of skim milk prior to MF was facilitated using an Ionics (Ionics Inc.)
Electromat
ED, featuring a 100-cell pair Mark III electrodialysis membrane stack. Electrodialysis
resulted in improvements in the heat stability profile of phosphocasein, at the expense of rennet
coagulation properties which were totally eliminated even in the presence of added calcium.
'cold' whey ultrafiltration / whey protein concentrate / phosphocasein
Correspondence and reprints: P.-M. Kelly
pkelly@moorepark.teagasc.ie
Copyright INRA, EDP Sciences