Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-03T03:13:12.225Z Has data issue: false hasContentIssue false

223. Bacteriological studies of canned milk products

Published online by Cambridge University Press:  01 June 2009

Agnes A. Nichols
Affiliation:
The Hannah Dairy Research Institute, Kirkhill, Ayr

Extract

1. A survey of evaporated milk and canned cream samples from three condensed milk factories and from general sources has been undertaken to determine to what extent non-sterility occurred in commercial practice. In addition to the examination of sound samples many others have been tested which were obviously defective or which were associated with defective packs. 100% of the tins examined from general sources were sterile. The factory samples, especially those of canned cream, had a lower sterility percentage, although it appeared that this was associated with some special circumstance of operation and that a sterile pack should ordinarily be quite attainable.

2. An account is given of the methods used for sampling the can contents and for the recovery of bacteria from unsterile cans and their identification. The necessity for a large inoculum in such sampling is emphasized, since although the bacteria may survive for many months in the tins, they may be present in small numbers.

3. Data are presented regarding the types of defective samples encountered and the associated bacteriological flora. “Bloats” in evaporated milk and thin bitter and putrid cream were the two main causes of spoilage encountered.

4. By using the heat resistance of the organisms which were recovered from the cans as a basis of classification the. defects have been divided into two groups, namely (1) a mixed general flora which does not withstand high temperatures, and (2) a restricted heat resistant flora which is of the sporeforming type.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1939

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

(1) Savage, & Hunwicke, (1923). Spec. Rep. Food, Invest. Bd, Lond., no. 13.Google Scholar
(2) Allen, (1932). Bull. Hannah. Dairy Res. Inst. no. 3. oGoogle Scholar
(3) Esty, & Stevenson, (1925). J. infect. Dis. 36, 986.CrossRefGoogle Scholar
(4) Hammer, (1927). la St. Coll. J. Sci. 2, 1.Google Scholar
(5) Hunziker, & Wright, (1910). Purdue Agric. Exp. Sta.Google Scholar
(6) Hammer, (1917). Res. Bull, la agric. Exp. Sta. no. 38.Google Scholar
(7) Hunziker, (1935). Condensed Milk and Milk Powder, 5th ed., 445.Google Scholar
(8) Gibson, & Topping, (1936). Soc. Agric. Bad. Conf., Reading.Google Scholar
(9) Gibson, (1937). Soc. Agric. Bad. Conf.,Edinburgh.Google Scholar
(10) Gibson, (1938). Soc. Agric. Bad. Conf.,Bristol.Google Scholar
(11) Howat, , Jackson, & Nichols, (1937). Milchw. Weltkongress, 2, 241.Google Scholar
(12) Nichols, & Jackson, (1938). Soc. Agric. Bad. Conf,Bristol.Google Scholar
(13) Nichols, , Howat, & Jackson, (1937). J. Dairy Res. 8, 331.CrossRefGoogle Scholar
(14) Wilson, & Shipp, (1938). Chem. Ind. 57, 834.CrossRefGoogle Scholar
(15) Cameron, & Esty, (1926). J. infect. Dis. 39, 89.Google Scholar
(16) Thayer, (1912). Bull. Ver. agric. Exp. Sta. no. 170.Google Scholar
(17) Hammer, & Hussong, (1932). J. Dairy Sci. 15, 220.Google Scholar
(18) Kelly, (1926). Trans, roy. Soc. Can. section v, 387.Google Scholar
(19) Morrison, & Rettger, (1930). J. Bad. 20, 299.Google Scholar
(20) Hammer, (1915). Res. Bull. la agric. Exp. Sta. no. 19.Google Scholar
(21) Hunziker, & Cordes, (1923). Quoted from Hunziker, , Condensed Milk and Milk Powder, ed. v, 442.Google Scholar
(22) Sarles, & Hammer, (1932). J. Bad. 23, 301.Google Scholar
(23) Hussong, & Hammer, (1931). la State Coll. Agric. J. Sci. 6, 89.Google Scholar
(24) Guide to the Conduct of Clean Milk Competitions (1934). Bull. Min. Agric., Lond., no. 46.Google Scholar
(25) Rice, & Downs, (1923). J. Dairy Sci. 6, 532.Google Scholar
(26) Downs, (1925). J. Dairy Sci. 8, 344.CrossRefGoogle Scholar
(27) Rogers, , Dahlberg, & Evans, (1920). J. Dairy Sci. 3, 122.CrossRefGoogle Scholar
(28) Knudsen, (1922). Den. Kgl. Veterinaerog. Landbohøjskoles Aarsskrift, p. 282.Google Scholar
(29) Smith, (1938). London School of Hygiene and Tropical Medioinei Private communication.Google Scholar