1.1 FDA Food Code & Temperature Control

FDA Food Code & Temperature Control

Core Principle: Temperature control is the most effective way to prevent foodborne illness. By controlling the amount of time Time/Temperature Control for Safety (TCS) foods spend in the Temperature Danger Zone, you disrupt the bacterial growth cycle.

The FDA Food Code serves as a scientifically based model for regulating retail and food service segments of the industry. While the FDA publishes the Food Code, it is not federal law. Instead, it is offered for adoption by local, state, and federal governmental jurisdictions. Updates are generally issued every four years. A profound understanding of the Food Code's temperature parameters is paramount for any Registered Environmental Health Specialist (REHS) conducting inspections, as temperature abuse is a leading cause of foodborne illness outbreaks.

The Temperature Danger Zone (TDZ)

The Temperature Danger Zone (TDZ) is defined as the temperature range between 41°F and 135°F (5°C to 57°C). Within this range, pathogenic bacteria can survive and multiply rapidly. If TCS foods remain in the TDZ for too long, the pathogens can reach infectious levels or produce heat-stable toxins that cannot be destroyed by subsequent cooking.

Bacterial Growth Phases

Understanding the bacterial growth curve is essential for sanitarians:

1. Lag Phase: Bacteria adjust to their environment. Growth is slow. Proper refrigeration prolongs this phase.
2. Log (Exponential) Phase: Bacteria multiply rapidly, doubling as often as every 20 minutes under ideal conditions in the TDZ.
3. Stationary Phase: The number of new bacteria equals the number dying as resources deplete.
4. Death Phase: Bacteria die off faster than they multiply due to lack of nutrients or toxic waste buildup.

To keep bacteria in the lag phase and prevent the explosive log phase, strict adherence to cold holding and hot holding requirements is required.

Holding Temperatures

Cold Holding

All cold TCS foods must be maintained at 41°F (5°C) or below. At these temperatures, bacterial metabolism slows significantly, extending the lag phase. When inspecting, the REHS should check the internal temperature of the food, not just the ambient air temperature of the cooler.

Hot Holding

All hot TCS foods must be maintained at 135°F (57°C) or above. High temperatures prevent vegetative bacterial cells from multiplying. Note that roasts can be held at 130°F under specific oven parameters, but 135°F is the standard for general hot holding.

Cooking Temperatures

Cooking food to the correct internal temperature destroys vegetative pathogens (though it does not destroy spores or heat-stable toxins). The FDA Food Code establishes minimum internal cooking temperatures based on the type of food and the pathogens typically associated with it. The temperature must be maintained for a specific time, usually 15 seconds, to ensure lethality.

The Two-Stage Cooling Process

Improper cooling of hot foods is one of the most common causes of foodborne illness. When a large batch of hot food is placed directly into a refrigerator, the core can remain in the TDZ for days. The FDA Food Code requires a two-stage cooling process to move food quickly through the most dangerous part of the TDZ (135°F to 70°F), where spore-forming bacteria like Clostridium perfringens and Bacillus cereus germinate rapidly.

The Rule:

• Stage 1: Cool from 135°F to 70°F within 2 hours.
• Stage 2: Cool from 70°F to 41°F or below within the next 4 hours.
• Total Time: The entire process must not exceed 6 hours.

If the food does not reach 70°F within the first 2 hours, it must be reheated to 165°F for 15 seconds and the cooling process restarted, or the food must be discarded.

Approved Cooling Methods

An REHS should look for these methods during an inspection to verify active cooling:

• Placing food in shallow pans (no more than 2-3 inches deep).
• Dividing food into smaller or thinner portions.
• Using rapid cooling equipment like blast chillers.
• Stirring the food in a container placed in an ice-water bath.
• Using ice paddles or cooling wands to stir hot liquids.
• Adding ice as an ingredient.

Reheating for Hot Holding

When previously cooked and cooled TCS food is reheated for hot holding, it must be rapidly heated to an internal temperature of 165°F for 15 seconds within 2 hours. The rapid heating ensures the food does not linger in the TDZ. Reheating equipment must be capable of achieving this; steam tables and hot holding units are generally not designed for reheating and should only be used to hold food already at 135°F or higher.

Dry Storage Requirements

While temperature control focuses heavily on TCS foods, ambient conditions in dry storage are also regulated to prevent spoilage, mold growth, and pest infestations.

• Temperature: Dry storage areas should be maintained between 50°F and 70°F.
• Relative Humidity: Humidity should be kept between 50% and 60%.

Elevated humidity can cause canned goods to rust, leading to compromised seals and botulism risks, while dry goods like flour and sugar can absorb moisture and become caked or moldy. Proper ventilation is necessary to maintain these conditions.