摘要:

Examination of a holder pasteurizing plant giving occasional apparently inexplicable phosphatase test failures proved that excessive froth on the surface of the milk during holding, resulting from an unsuitable type of pre‐heater, was causing the trouble. Uninsulated lids allowed considerable loss of heat from the froth. Other plants of the same make were examined and the same inherent faults found.Two other makes of holder plant with well insulated lids were also tested. There was a large air space under the lid in one plant in which phosphatase test failures occurred in the froth and surface milk, whereas the other plant, with no air space, gave no failures.One hundred bacterial cultures from two bulked froth samples from two plants were tested for heat resistance. A number of these, including a streptococcus, a sarcina, a micrococcus, and several Gram‐negative rods, were found to have heat resistance similar to that of tubercle baci

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05035.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

摘要:

during the examination of chilled water from a churn immersion cooler it was observed that when the water was not changed at frequent intervals the colonies on standard nutrient agar incubated at 22° became entirely composed of aFlavobacteriumsp. Colony counts greater than 106/ml. were obtained at 3–5° and 22°. Although the dominant organism produced no visible change in litmus milk yet 0.1 ml. of chilled water clotted the milk within 48 hr. at

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05036.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

摘要:

An apparatus is described in which side illumination from strip lights gives clear illumination without glare of colonies against a black background. The Petri dish lies in an unrestricted field and removal of the lid is unnecessary.

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05037.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

摘要:

The milk production conditions on 44 farms (18 designated and 26 non‐designated) have been assessed by score‐card marks for visual conditions, facilities, equipment, and methods. Over a period of one year fortnightly samples from these farms were subjected to routine resazurin tests and laboratory pasteurized counts. The results were compared with the total score‐card marks and the equipment assessments of the farms. It was found that neither test alone sufficed to detect unsatisfactory production, but failure on the two tests combined agreed well with the production conditions and facilities.The relation of season and mean shade atmospheric temperature to the thermoduric bacterial content of the milk was studied but no clear association was obs

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05038.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05039.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05040.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05041.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05042.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY

ISSN:0370-1778    

DOI:10.1111/j.1365-2672.1950.tb05034.x

出版商:Blackwell Publishing Ltd    

年代:1950

数据来源: WILEY