[Report of the Medical Officer of Health for Port of London].

  • London (England). Port Health Authority.
Date:
1968
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: [Report of the Medical Officer of Health for Port of London]. Source: Wellcome Collection.

    34/54 (page 32)
    Wide variations will be observed between rot fragment counts on samples of similar mould count. Such variations may be ascribed partly to experimental error, arising from the application of a high factor to a small count, and partly to variations of assessment by four different operators over the period. It will however also be observed if the results for all samples of similar mould count are averaged that a distinct relationship appears between the two methods. It is suggested therefore that if the procedure of the Rot Fragment Count were amplified so as to obtain more uniform counts the result might afford a useful confirmation of the Howard Mould Count; and that if the relationship showed any marked departure from normal, it would indicate conditions in the puree that might affect the conclusion to be drawn from the Mould Count. Fly Eggs, Maggots, Mites For further evidence of the use of damaged fruit the A.O.A.C. First Action method 36/073, is worthwhile and often provides interesting results. Coulter's modification13 provides a cleaner re sidue by digesting the tomato tissue with sodium phosphate. 100 g. of sample is suitably diluted and digested with trisodium phosphate added to give a pH of 7.5-8.5; boiled for 5-10 minutes, then washed first through a No.10 sieve if seeds are present and secondly through a No.80 sieve until there is no further reduction in the volume of the residue, which is then transferred to a cloth or filter for counting. 32