Hygiene in catering establishments / report of the Catering Trade Working Party.

  • Great Britain. Catering Trade Working Party.
Date:
1951
Catalogue details

Licence: Public Domain Mark

Credit: Hygiene in catering establishments / report of the Catering Trade Working Party. Source: Wellcome Collection.

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    + eso Ae Sars eee cee Penal oo Og leks” Te Voges) ae en Ls | ae FL ME RES ee Bee Fe et Te Gee Sot Up i ; ” =e Pa v = (3) G) Immersion for fifteen seconds in clean water maintained at a temperature of 170°F., or an equally effective process of sterilisation by heat, or (ii) immersion for an adequate period in a solution of an effective concentration of a suitable batericidal substance, such as a quaternary ammonium compound or a hypochlorite. In recommending a solution of a quaternary ammonium compound as one of the alternatives for the final rinse tank, the Committee recognises that the effective concentration of these compounds varies between the differ- ent members of the group and will need to be specified in the instructions issued by the manufacturers. After removal from the final rinse tank, crockery should be allowed to drain and should not be wiped with a cloth. Where a hot water rinse tank is employed, utensils may be allowed to drain in the same containers in which they were immersed in the tank. H. Use of Sequestering Agents In “hard ” water, alkalis and some detergents, such as soap, form insoluble calcium and magnesium compounds which usually appear on the surface as scum ; synthetic organic detergents are effective and free from scum forma- tion at all reasonable ranges of hardness, pH and salinity.* Although the scum is unsightly if allowed to dry on utensils, a more serious objection is the conclusion of several workers that calclum and magnesium films provide a good environment for the survival and growth of bacteria. Substances which will prevent the precipitation of insoluble compounds, such as those of calcium and magnesium, are known as sequestering agents. The agents most commonly used are inorganic compounds such as the alkali poly- phosphates. Certain organic compounds have been shown to be effective, and differ from the inorganic substances in not acting in stoichiometrical (i.e., chemically equivalent) proportions. Although sequestering agents are normally in- organic, the Committee feels that the use of organic compounds in the catering industry may be expanded. The Committee recommends that sequestering agents be incorporated in dish-washing preparations the use of which in hard water would otherwise lead to scum formation. When alkali polyphosphates are used, washing solutions should contain not less than the equivalent of 0°015 per cent. of P,O,, as polyphosphate. I. Washing Facilities in Licensed Premises The Committee briefly discussed the facilities available for washing glasses in the bars of licensed premises. The conditions prevailing are somewhat different from those in other catering establishments, and the problems are to some extent specific. Practically all cleaning is done at the bar counter, a quick turn round of glasses is frequently necessary and all methods are geared up to the “rush hours” such as the period immediately before closing time. Any system of glass washing must be satisfactory at these times, which are not only the most difficult but are also those at which cleaning needs to be most effective. The cleaning which takes place after closing time is probably generally satisfactory; as the public mostly like glasses to look bright and shining they are usually polished, after cleaning and draining, and put on shelves. NE * It is not necessary, of course, to employ sequestering agents with this type of detergent.
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