![]()
Section II
Application of Membrane Separation in Food Processing
![]()
4
Dairy Industry and Animal Products Processing Applications
Geneviève Gésan-Guiziou
Contents
4.1Dairy Industry
4.1.1Introduction
4.1.2Characteristics of Milk and Wheys
4.1.3Membrane Separations Applied to Milk
4.1.3.1Removal of Bacteria and Spores
4.1.3.2Fractionation of Fat Globules
4.1.3.3Standardization and Concentration of Milk Proteins
4.1.3.4Fractionation of Milk Proteins
4.1.3.5Fractionation of Individual Caseins
4.1.4Membrane Separations Applied to Whey and Derivates
4.1.4.1Concentration and Demineralization of Whey
4.1.4.2Concentration of Serum Proteins
4.1.4.3Fractionation of Individual Serum Proteins
4.1.4.4Fractionation of Peptides
4.1.5Treatment of Effluents and Technical Fluids
4.1.5.1Recovery of Process Waters
4.1.5.2Clarification of Brine
4.1.5.3Recycling of Cleaning Solutions
4.1.5.4Treatment of End-of-Pipe Wastewaters
4.1.6Conclusions and Future Trends
4.2Egg-Processing Industry
4.2.1Characteristics of Hen Egg (White, Yolk, and Whole)
4.2.2Concentration and Stabilization of Egg White and Whole Egg
4.2.2.1Concentration Before Spray Drying or Storage in Liquid Form
4.2.2.2Stabilization
4.2.2.3Types of Filtration Systems
4.2.3Extraction of Egg-White Proteins
4.2.4Conclusions and Future Trends
4.3Other Sectors
4.3.1Seafood Processing Industry
4.3.1.1Recovery of Proteins from Surimi Production
4.3.1.2Treatment of Other Effluents
4.3.1.3Fractionation and Concentration of Protein Hydrolysates
4.3.2Animal Products Industry: Blood and Gelatin
4.3.2.1Blood
4.3.2.2Gelatin
References
Over the past 30 years, the worldwide market for membrane operations in the food industry has increased to a market volume of about €800–850 million (Lipnizki, 2010). It has therefore become the second biggest market for membranes after water and wastewater treatment. This chapter will give an outlook of potential membrane applications in dairy and animal products processing. The first part of this chapter will focus on the dairy industry, the largest and most developed membrane market in the food sector, which has most successfully been able to put membranes to work for the benefit of the industry and its customers. The dairy sector encompasses a large variety of different products and membrane processes, and this chapter will give an overview of the most familiar and successful applications implemented throughout the processing chains (from product reception to wastewater treatment). The chapter will then present other established applications in the egg processing industry and other animal products processing, such as seafood, blood, and gelatin processing.
4.1Dairy Industry
4.1.1Introduction
In the food sector, the dairy industry has undoubtedly developed the most advanced extraction/separation procedures for concentration and fractionation molecules from milk and its derivatives. Processing each of the milk products (fluid milk, dried milk, cheese, etc.) is traditionally characterized by different operations of separation. The oldest operation is the standardization of milk fat content by centrifugal separation. But for more than 40 years, membrane filtration has been established as a common unit operation. The application of membrane operations to milk processing improves the separation options that are industrially applied today, enhancing the separation specificity (e.g., spores, somatic cells) and efficacy when compared to traditional technologies. It also enables the production of new, value-added-products for totally new and exciting applications.
The key membranes technologies in the dairy industry today are pressure-driven membrane processes such as microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO). Electrodialysis has only a small market. Based on their applicability range and specific membrane pore and cut-off it is possible to theoretically separate every milk component as shown in Figure 4.1. Pressure-driven membrane processes principally separate constituents according to molecule size relative to the pore size of the membrane, but it is practically experienced that apart from size, other properties of molecules such as charge, structure, shape, propensity to form gel, etc., play decisive roles in this respect and make membrane operations still complex because the various factors influencing separation results are not predictable.
Figure 4.1Approximate particle sizes of milk constituents for which separation by means of membrane filtration can be applied.
The use of membranes commenced in the late 1960s with the MMV process named after its inventors (Maubois, Mocquot, Vassal) and operated for the concentration of milk proteins. Membrane technology was also applied at this time to whey processing allowing the production of refined proteins and commercial usage, thus transforming a waste by-product from cheese production into valuable products. From then, the development of membrane applications in the dairy sector has been more or less tightly linked to the progress in membrane operations: asymmetric organic membranes in the late 1960s, composite inorganic membranes in the early 1980s, and porous ceramic membranes with multi-channel configuration in the early 1990s, which enabled the industrial application of the concept of uniform transmembrane pressure (UTP concept). The “UTP concept” was developed to reduce fouling phenomena and improve separation results by achieving an uniform transmembrane pressure over the entire length of the membrane by means of pumping the permeate (Sandblöm, 1974).
Among the membrane operations applied in the dairy sector, UF and RO are the oldest membrane processes. UF is the most widely used process, with membrane area installed specially for the concentration of the proteins contained in milk and wheys. The membrane area of RO is mainly used for whey concentration and has stabilized over the years. NF and MF have been developed since the mid-1990s at in...
