Automated food microbiology: potential for the hydrophobic grid-membrane filter

Automated food microbiology: potential for the hydrophobic grid-membrane filter.

Bacterial counts obtained on hydrophobic grid-membrane filters were comparable to conventional plate counts for Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus in homogenates from a range of foods. The wide numerical operating range of the hydrophobic grid-membrane filters allowed sequential diluting to be reduced or even eliminated, making them attractive as components in a...

Automation of microbial enumeration: development of a disposable hydrophobic grid-membrane filter unit.

A disposable filter unit containing a hydrophobic grid-membrane filter (HGMF) was developed. The unit is liquid tight to serve as a specimen transport container and, by removal of the funnel extender (175- or 300-ml capacity), the unit becomes less than the height of two stacked petri plates to save space during in situ incubation. The polyethylene mesh which supports the HGMF facilitates rinse...

Rapid hydrophobic grid membrane filter-enzyme-labeled antibody procedure for identification and enumeration of Escherichia coli O157 in foods.

An O-antigen-specific monoclonal antibody, labeled by horseradish peroxidase-protein A, was used in a hydrophobic grid membrane filter-enzyme-labeled antibody method for rapid detection of Escherichia coli O157 in foods. The method yielded presumptive identification within 24 h and recovered, on average, 95% of E. coli O157:H7 artificially inoculated into comminuted beef, veal, pork, chicken gi...

Food Microbiology

Hydrophobic grid-membrane filters: new approach to microbiological enumeration.

A square grid pattern, printed in hydrophobic material on conventional membrane filters, subdivided the surface into a plurality of areas. This separated colonies from one another and prevented lateral growth, spreading, and confluence. Very high colony-packing densities were achieved (2,500/in(2); ca. 1.61 x 10(5)/cm(2)) reducing the need to dilute samples. Recovery of organisms was better tha...