Polymers in the Dairy Industry

Maubois, J.L., Recent developments of ultrafiltration in the dairy industry, Polym. Sci. Technol., 13, 305,1980. 

RO membranes are characterized by a MWCO of 100 Da, and the process involves transmembrane pressures (TMPs) of 10-50 bar, which are 5-10 times higher than those used in UF [11,36]. Unlike UF, the separation by RO is achieved not by the size of the solute with respect to the membrane pore size but due to a pressure-driven solution-diffusion process [36]. In their early development, like UF membranes, RO membranes were uniquely structured films from synthetic organic polymers and consisted of an ultrathin skin layer superimposed on a coarsely porous matrix [3]. The skin layer of the RO membrane is nonporous, which may be treated as a water-swollen gel, and water is transported across membrane by dissolving in this gel and diffusing to the low-pressure side [3]. In the dairy industry, RO is used to concentrate milk or whey by removal of water and ionized minerals [11]. 

Duan X, Chi Z, Wang L, Wang X (2008) Influence of different sugars on pullulan production and activities of a -phosphoglucose mutase, UDPG-pyiophosphorylase and glucosyltransferase involved in pullulan synthesis in Aureobasidium pullulans Y68. Carbohydr Polym 73 587—593 Duboc P, Mollet B (2001) Applications of exopolysaccharides in the dairy industry. Int Dairy J 11 759—768... 

It has been accounted that, on a production scale of PHB of 100,000 tons per year, the production costs will decrease from US 4.91 to US 3.72 kg , if hydrolysed com starch (US 0.22 kg ) is chosen as the carbon source instead of glucose (US 0.5 kg ) [33]. But this is still far beyond the cost for conventional polymers, which in 1995 was less than US 1 [32]. Lee et al. estimated that PHB and mcI-PHA can be produced at a cost of approximately US 2 kg [36]. The precondition therefore would be attaining high productivity and the use of inexpensive carbon sources. Among such substrates, molasses [37], starch [38], whey from the dairy industry [37-42], surplus glycerol from biodiesel production [39, 43], xylose [44, 45], and plant oils [46] are available. 

The main oudet (65%) for pure g. is the food market confectionery, desserts, dairy products and carmed meats are only a few products wiiere g. is used. In the pharmaceutical industry (10%), the most important application is for the manufacture of capsules. Another use is as tablet binder. An old but sensitive application is photographic emulsions (20%). No synthetic polymer has succeeded to at-... 

In preparing emulsions, many factors concerning their end-use have to be taken into account. Often, their preparation is merely an enabling step towards, for example, formation of disperse polymer systems, or enhancing a liquid/liquid extraction process. However, in many situations the emulsion is itself the end product. Abundant examples of where this is the case are to be found in the pharmaceutical, food, paint, dairy, agrichemical, cosmetic, adhesives and detergents industries. In these situations, as opposed to those where emulsification is an intermediate step, we are invariably more closely concerned with two key properties - rheology and stability. 

Fluorosilicones (FLS) are a class of polymers generally composed of siloxane backbone polymers and fluorocarbon pendant groups. Fluorosilicone materials are familiar because of their excellent properties such as high thermal stability, good chemical and environmental resistance, flame resistance, and surface characteristics. Currently, these materials are extensively used in a wide range of applications such as in the electronic, automotive, dairy, medical, and aerospace industries [1,2]. The primary and most commonly used commercially available fluorosilicone is poly(3,3,3-trifluoropropyl methylsiloxane (PTF-PMS). This polymer was discovered by Dow Coming Company [3] in 1950 and was given the trade name Silastic . It is prepared from l,3,5-trimethyl-l,3,5-tra(3, 3, 3 -trifluoropropyl)cyclotrisiloxane and has the repeat unit sfructure presented in Scheme 6.1. 

Although the main areas of NIR analysis were agriculture and food industry [270], today all fields of research and quality control seem to be concerned cfr. also ref. [271]). Applications of NIR spectroscopy are now found in many areas polymers, petrochemicals, textiles, pharmaceuticals, agricultural products, dairy products, packed products, beverages, etc. [272]. Some 450 NIR analysers are operative in the Benelux area only. 

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