摘要:

SUMMARY:The relatively high mould‐resisting qualities of both wood pulp and felt board as compared with composition cork are not due to the presence of fungistatic substances. Wood pulp board withstands mould attack because of its comparatively inert nature. The apparent fungistatic property of felt is due mainly to the fact that a high humidity is necessary for it to support growth; when used in bottle closures the humidity at the interface between cap and wad is normally below that required for mould development on this material. Under conditions where mould could occur, growth at the interface seems to be limited by mechanical restrictio

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00011.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

SUMMARY:A numerical analysis is given of the average microflora of fermenting cocoa beans in Trinidad sweat boxes. Both the viable count of all micro‐organisms and the relative numbers of the main groups involved were estimated.The influence of the prevailing temperature and pH of the environment on the sequence of microbial development is considered, and the main chemical changes taking place are noted.The influence of atmospheric conditions is discussed and the desirability of a thorough microbiological analysis of the fermentation process in relation to cocoa quality is stresse

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00012.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

SUMMARY:The bacterial colony count of raw milk and of milk powder using milk agar prepared from a proprietary brand of the dehydrated medium has been compared with that obtained using the fresh medium prepared in the laboratory.No significant difference was found in 17 milks which were examined using the roll‐tube technique and 8 replicates/medium but in a second series of 32 milks the plate count (3 replicates/medium) was significantly lower on the reconstituted than on the fresh medium.Some milk powders gave a much lower plate count on the reconstituted medium, due to the inability of the latter to support adequate growth ofStreptococcus thermophilu

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00013.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

SUMMARY:The effects of shaking milk samples before the addition of methylene blue, delaying the time of addition of the dye, adding a second quantity of dye with a hypodermic syringe after the initial charge had been decolourized and of increasing the storage time or varying the testing time have been studied in five separate experiments. Vigorous shaking at the time of dye addition lengthened the reduction time. This effect was more pronounced when the milk was stored in a tube than in a bottle. Delayed addition of the dye resulted in a shorter reduction time than expected for inverted samples and longer than expected for samples which were not inverted between the time they were put into the 37° bath and the addition of the dye. Second additons of dye did not usually have reduction times exceeding 1 hr. Methylene blue reduction times did not necessarily decrease with successive tests carried out over a period of time on one sample: a time of 30 min. might persist over a series of tests for 4 hr. or more and small increase and decrease in reduction time with successive tests were also noted

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00014.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

摘要:

SUMMARY:A study of the relative values of a number of bacteriological tests for assessing the condition of milk bottles indicated that the colony count of the bottle rinse solution on yeastrel milk agar incubated for 4 days at 30°, combined with a clot‐on‐boiling test applied to 1 ml. of rinse in 9 ml. of sterile milk after incubation for 72 hr. at 19–20°, gave the most useful results.The mean of the ratios of colony counts at 30° to those at 37° was 15·1, while it was as high as 22·9 for rinses with 37° of over 600 for an unsatisfactory bottle should be retained when the test is done at 30°. The thermoduric colony count of rinses of milk bottles, even when laboratory pasteurized in milk, did not provide any additional information to that given by the colony count at 30° made without pasteurization. A high proportion of the organisms in bottle rinses survived laboratory pasteurization in milk, the survival rate being highest in efficiently treated bottles.The clot‐on‐boiling test gave results in general agreement with colony counts and served to indicate the potential influence of badly contaminated bottles on the keeping quality of milk placed in them. A substantial proportion of rinses with satisfactory colony counts reduced methylene blue within 48 hr. at 19–20°.Colony counts at 37° were on the average much lower for bottles treated with steam than for bottles submitted to detergent treatment in various types of bottle washing machines. Treatment of bottles by steam or hypochlorite was more efficiently done on the far

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00015.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00016.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00017.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00018.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1952.tb00019.x

出版商:Blackwell Publishing Ltd    

年代:1952

数据来源: WILEY