# Presentation: 094230

## Guidance for Industry: Control of Listeria monocytogenes in Refrigerated or Frozen Ready-to-Eat Foods 

**Don L. Zink**
**US Food and Drug Administration**
**Center for Food Safety and Applied Nutrition**

## Control of L. monocytogenes

**Formulation of refrigerated RTE foods to prevent the growth of *****L. monocytogenes***
**Prevention of contamination during manufacturing**
**Important for non-growth foods, but critical for foods that support growth**
**Focused on RTE refrigerated and frozen foods**

## Overview of the Guidance Document

**Who should use this guidance and how it relates to other FDA regulations**
**Formulation of foods to prevent the growth of *****L. monocytogenes***
**Listericidal measures**
**Raw ingredient controls**
**Storage practices**
**Controls regarding personnel**
**Facility controls – plant design, construction and operation**
**Equipment controls – design and maintenance**
**Sanitation controls**
**Environmental monitoring**
**Finished product testing**
**Corrective actions**
**Record keeping**

## Who Should use the Guidance and how does it relate to FDA Regulations?

**Processors of refrigerated RTE (RF-RTE) foods**
**Processors of fresh-cut fruits and vegetables**
**Processors of frozen foods and other non-growth foods**
**Guidance does not establish legally enforceable responsibilities**
**Recommendations based on the Agency’s current thinking**

## Formulating Foods to Prevent the Growth of L. monocytogenes

**Foods that support the growth of *****L. monocytogenes***** present the highest risk**
***Listeria***** will not grow in foods that:**
**Have a pH of **_**<**_** 4.4,**
**Have a water activity of **_**<**_** 0.92, or**
**Are stored and marketed as a frozen food**
**Combinations of intrinsic factors can be used to prevent the growth of *****Listeria *****(the “hurdle concept”)**
**Combination of reduced pH and reduced water activity**
**Use of an antimicrobial substance(s). e*****.g.*****, sorbic acid**
**When using the “hurdle concept” it is recommended that you validate the effectiveness of the listeristatic controls and implement controls to ensure that the antimicrobial formulation is consistently manufactured**

## Use of Listericidal Measures

**Demonstrate the efficacy of the control measure:**
**Reference to scientific literature or previous validation studies**
**Scientifically valid experimental trials**
**Statistically designed surveys and/or mathematical modeling**
**We recommend that you establish and implement controls to ensure that the listericidal measure is consistently applied during manufacturing**

## Raw Ingredient Controls

**Identify ingredients that are reasonably likely to be contaminated with *****L. monocytogenes***
**Establish appropriate controls for each of these ingredients**
**Treat these ingredients with a listericidal control measure**
**Establish controls to reduce the potential that these ingredients will be contaminated**
**Purchase ingredients from suppliers that produce their products in a manner consistent with these guidelines**

## Storage Controls

**Establish procedures to minimize the time that  ingredients, in-process materials and finished products are stored**
**Use first-in-first-out inventory controls**
**Transport and store ingredients, in-process materials and products at 40 F or less**
**Minimize the amount of time that ingredients, in-process products, and  finished products are held at temperatures above 40 F**

## Controls Regarding Personnel

**Training in health and hygienic practices for all employees who enter food production and storage areas**
**Exclude employees with symptoms of gastroenteritis from food production areas**
**Ensure that maintenance personnel adhere to appropriate hygienic practices**
**Other practices:**
**Proper hand washing**
**Appropriate use of gloves**
**Appropriate footwear**
**Smocks or uniforms are preferable to street clothes**

## Facility Controls – Design, Construction and Operation

**Separate areas where RF-RTE foods are produced or exposed from areas where raw foods are processed, exposed or stored**
**Appropriate air flow and air filtration throughout the facility**
**Appropriate water systems maintained to prevent back flow and cross-connections**
**Properly designed drains and drainage systems**
**Constructed to facilitate cleaning in areas where RF-RTE foods are processed**
**Control traffic flow to prevent transfer of contamination from raw food areas to areas where RF-RTE foods are processed or exposed**
**Dedicate equipment and containers by function and by area (raw *****vs.***** processed)**
**Avoid creating aerosols that could contaminate areas where RF-RTE foods are processed or exposed                                                                        **

## Equipment Controls – Design and Maintenance

**Equipment for the production of RF-RTE foods should be readily cleanable**
**Design and construct production areas to protect equipment used to process RF-RTE foods from source of contamination**
**Food contact surfaces should be smooth, non-absorbent and easily cleanable**
**Tools for maintenance of RF-RTE food production areas should be dedicated to those areas**
**Clean and sanitize equipment and food contact surfaces where RF-RTE foods are processed or exposed after maintenance and before production**

## Sanitation Controls

**Establish and use a sanitation program that includes a written sanitation standard operating procedure (SSOP) for areas where RF-RTE foods are processed or exposed**
**A written SSOP should address:**
**The cleanliness of food contact surfaces, equipment, utensils, gloves and outer garments**
**The prevention of cross-contamination**
**Written SSOPs should include the equipment to be cleaned, disassembly of equipment****, cleaning frequency, type and concentration of chemicals and other important steps and procedures**

## Environmental Monitoring

**We recommend that you establish and implement a written plan for the collection of environmental samples from critical surfaces and areas and for testing those samples for *****Listeria***** species or *****L. monocytogenes***
**Evaluate each plant, product and process to determine the appropriate monitoring points**
**Food contact surfaces should be tested prior to cleanup and no sooner than the middle of production**
**The number of samples you collect depends on the size of your processing line, but even the smallest processors should collect a minimum of 5 sites of food-contact surfaces in each RF-RTE production line.**

## Finished Product Testing

**Establish and implement a written plan for the periodic collection and testing of finished products for *****Listeria *****species or *****L. monocytogenes***
**The purpose of testing is to serve as an ongoing validation of the adequacy of your controls and to establish a historical reference**
**Finished product testing is not done for the purpose making release decisions on a lot-by-lot basis**

## Corrective Actions

**If you detect *****Listeria *****species or *****L. monocytogenes ***** on a critical surface or in food, we recommend that you follow a corrective action plan that describes the steps to be taken and responsibility assigned**

## Record Keeping

**Document listeristatic control measures**
**Document listericidal control measures**
**List ingredients reasonably likely to be contaminated with *****L. monocytogenes***
**Retain certificates of analysis or conformance**
**A written plan for sampling and testing the environment**
**A written plan for sampling and testing RF-RTE foods**
**Written analytical methods, including the sensitivity of the method**
**Results of tests that you conduct to detect or enumerate *****Listeria *****sp. or *****L. monocytogenes***