KANSAS CITY, MO. -- According to USDA guidance documents on the control of Listeria in ready-to-eat foods, some specific scenarios in processing facilities that could lead to contamination with Listeria include:

A packaging line is moved or modified significantly.

    Used equipment is brought from storage or another plant and installed into the process flow.

An equipment breakdown occurs.

    Construction or major modifications are made to an area where RTE foods are processed or exposed (replacing refrigeration units or floors, replacing or building walls, modifying sewer lines).

A new employee, unfamiliar with Listeria controls, has been hired to work in, or to clean equipment in, the area where RTE foods are processed or exposed.

    Personnel who handle RTE foods touch surfaces or equipment likely to be contaminated (floor, trash cans) and do not change gloves or follow other required procedures before handling the food.

Periods of heavy production make it difficult to clean the floors of holding coolers as scheduled.

    A drain backs up.

Product is caught or hung-up on equipment – (stagnant product in a system can be a major site of microbial growth during production.)

    Raw or under-processed foods are placed in an area designated for cooked foods.

Frequent product changes on a packaging line cause a change in packaging film, labels, forming pockets or molds, line speeds, etc.

    Personnel are used interchangeably for packaging raw and cooked foods.

Increased production causes employees to perform wet cleaning of lines that have been taken down from production in the same room as lines that are running product.

    Equipment parts, tubs, screens, etc. are cleaned on the floor.

Waste bins in the RTE area aren’t properly maintained, cleaned and sanitized.

    Re-circulating pumps and lines are not cleaned and sanitized.

Indiscriminate use of high-pressure hoses in cleaning.

    Inappropriate use of footbaths in dry processing areas.

Water is sprayed on wheels on transport cars when in-process product is stored near the wheels.

M+P’s Sanitation Tips are to be used only as guidelines for cleaning and sanitizing processing facilities. Specific issues and questions should be addressed by a sanitation crew supervisor.