Plastics in gastronomy.
Division of plastics. According to the applications, plastics are divided into:
• construction plastics - for the production of utility items,
• coating materials - for permanent coating of finished metal products, wood etc.. for decorative and protective purposes,
• adhesive materials (glues, whales) - for joining different materials,
• impregnating materials - for wood refinement, paper, fabrics.
Due to the possibility of plastic processing, plastics are divided into:
• thermoplastic - plastic at elevated temperatures, a hardening on cooling, can be reworked many times,
• thermoset - transforming irreversibly from a plastic state into a hardened state under the action of temperature,
• coagulating - in liquid form, solids upon evaporation of the solvent or the use of a coagulation bath (shear).
Plastics in gastronomy. Some plastics are used in the production of small equipment, machines and equipment for catering establishments. Belong to them:
• Viscose foil (cellophane) transparent, non-toxic, resistant to fats and oils, gauze- and vapor-tight, hygroscopic, susceptible to printing, not susceptible to welding. It is used for sausage casings, food packaging.
• Aminoplasty (melamine) - water resistant, high temperature and light. They are used for laminated boards, tableware, installation components.
• Polyethylene (PE) - resistant to low temperatures, poorly absorbing water, chemically resistant, not susceptible to varnishes and adhesives. Easily dyed and melted. Applies to food packaging (bottles, jars, buckets, bags).
• Polyvinyl chloride (PCW — winidur) - hard, not very springy, brittle at low temperatures, chemically resistant, glues and welds well, easily molds hot; it can be tinted in different colors. It is used in the manufacture of kitchen equipment (tace, cathedrals, rolling pins) and sanitary installations, building and furniture elements.
• Polichlorek vinylidenu (saran) - oil resistant, fats and chemicals and at temperatures from -20 to + 90 ° C; it is characterized by high mechanical strength. It is used for shrink wrapping films, mainly for frozen food (especially poultry).
• Police rules (S, K) - non-toxic, resistant to alcohol, water, oils and acids, except concentrated nitrogen, not resistant to organic solvents. It is used for decorative products, containers for food and for non-alcoholic drinks.
• Polytetrafluoroethylene (teflon) - non-toxic, temperature resistant up to 250 ° C, chemically resistant, does not absorb water, it is an excellent insulator. It is used for linings of heating apparatuses (piece, frying pans without fat, dishes) and cake making machines, valves for acids and bases, seals etc..
The advantages of plastic products include: lightness, possibility of giving any color, good insulating properties, easier to keep clean than wooden products. The disadvantages are: susceptibility to scratches and cracks, softening in contact with oil, fragility, fragility, low resistance to high and low temperatures and the toxicity of some of them in contact with food. Maintenance of equipment made of plastic consists of washing in soapy water, rinsing in hot water, air drying. Such equipment should be protected against overheating, especially against direct contact with fire.