5.4 FDA Food Code: Time/Temperature Control for Safety (TCS) Foods

5.4 FDA Food Code: Time/Temperature Control for Safety (TCS) Foods

Exam Key: TCS food (formerly designated as Potentially Hazardous Food or PHF) requires specific time and temperature controls to limit infectious or toxigenic microorganism growth. The NEHA CP-FS exam heavily tests exact temperature thresholds, dwell times, cooling rules, date marking limits, and TPHC provisions under the 2022 FDA Food Code.

Definition of TCS Food

A Time/Temperature Control for Safety (TCS) food is defined by the FDA Food Code as a food that requires time/temperature control for safety to limit pathogenic microorganism growth or toxin formation.

Intrinsic Parameters: Water Activity ($A_w$) & pH Matrices

Food safety classification relies on intrinsic factors, specifically water activity ($A_w$) and pH. Unprocessed animal foods (raw or heat-treated) and plant foods with $A_w > 0.85$ and $pH > 4.6$ are classified as TCS foods unless scientifically proven non-TCS via interaction tables in the FDA Food Code (Table A and Table B under Annex 8).

Foods Classified as TCS Food

• Animal Foods: Raw or cooked meat, poultry, fish, shellfish, crustaceans, milk, and raw shell eggs.
• Specific Plant Foods (Heat-Treated or Cut):
  • Cooked plant foods (e.g., cooked rice, beans, pasta, potatoes).
  • Cut Leafy Greens: Iceberg, romaine, spinach, leaf lettuce, kale, or salad mixes that have been cut, shredded, sliced, chopped, or torn.
  • Cut Tomatoes: Tomatoes that have been sliced, diced, or chopped.
  • Cut Melons: Watermelon, cantaloupe, or honeydew that have been cut.
  • Raw Seed Sprouts: Alfalfa, mung bean, or clover sprouts.
  • Garlic-in-Oil Mixtures: Untreated garlic-in-oil mixtures (unless modified with acidifying agents to maintain $pH <= 4.6$ or reduced $A_w$).

Non-TCS Exceptions

• Air-cooled hard-boiled eggs with intact shells.
• Food in unopened, commercially sterile, hermetically sealed containers.
• Foods with low water activity ($A_w <= 0.85$) or high acidity ($pH <= 4.2$ standalone, or specified matrix combinations).

---

Minimum Internal Cooking Temperatures & Dwell Times

Cooking TCS food to required minimum internal temperatures for specified dwell times ensures destruction of target vegetative pathogens (e.g., Salmonella, E. coli O157:H7, Campylobacter).

Microwave Cooking Requirements

When cooking raw animal foods in a microwave oven, the food must be cooked to at least 165°F (74°C) in all parts, covered to retain surface moisture, rotated or stirred halfway through, and allowed to stand covered for 2 minutes post-cooking to equalize temperature.

---

Holding & Cooling Protocols

                      TEMPERATURE DANGER ZONE (TDZ)
                    41°F (5°C)  ────►  135°F (57°C)
            [Rapid Pathogen Multiplication Zone: 70°F to 125°F]

  ◄── Safe Cold Holding                             Safe Hot Holding ──►
   (41°F / 5°C or lower)                           (135°F / 57°C or higher)

Hot and Cold Holding Standards

• Hot Holding: Maintain TCS food at 135°F (57°C) or higher.
• Cold Holding: Maintain TCS food at 41°F (5°C) or lower.

Two-Step Cooling Protocol (FDA Food Code § 3-501.14)

When cooling hot TCS food, it must pass through the Temperature Danger Zone rapidly to prevent spore-forming bacteria (such as Clostridium perfringens and Bacillus cereus) from germinating and multiplying:

• Step 1: Cool hot TCS food from 135°F (57°C) to 70°F (21°C) within 2 hours.
• Step 2: Cool from 70°F (21°C) to 41°F (5°C) within an additional 4 hours.
• Total Maximum Cooling Duration: 6 hours total.

Corrective Action: If food does not reach 70°F within the initial 2 hours, it must be reheated to 165°F for 1 second and re-cooled, or discarded.

Approved Rapid Cooling Methods

• Dividing food into shallow stainless steel pans (product depth $<= 2$ inches for thick foods, $<= 3$ inches for liquids).
• Placing food containers in ice-water baths while stirring frequently.
• Using blast chillers or rapid cooling equipment.
• Utilizing hollow ice-paddles / ice wands to stir hot liquids.
• Adding ice as an ingredient to concentrated stocks or soups.

---

Date Marking & Time as a Public Health Control (TPHC)

Ready-to-Eat (RTE) TCS Food Date Marking

Refrigerated, Ready-to-Eat (RTE) TCS food prepared and held in a food establishment for more than 24 hours must be date-marked:

• Maximum Shelf Life: Held at 41°F (5°C) or lower for a maximum of 7 days.
• Day Calculation: Day 1 is the day of preparation or the day a commercial container is opened.
• Combined Ingredients Rule: When mixing commercially prepared RTE ingredients or multi-day components, the discard date is governed by the earliest-prepared ingredient.

Time as a Public Health Control (TPHC) (FDA Food Code § 3-501.19)

If temperature control is not maintained, time alone can be used as a public health control under strict operational conditions:

1. Four-Hour Rule (Hot or Cold TCS Food)

• Initial temperature must be 41°F (5°C) or lower (when removed from cold holding) or 135°F (57°C) or higher (when removed from hot holding).
• Maximum display duration: 4 hours.
• Food must be served, sold, or discarded within 4 hours. Unserved food cannot be returned to refrigeration or re-heated.

2. Six-Hour Rule (Cold TCS Food Only)

• Initial temperature must be 41°F (5°C) or lower when removed from cold storage.
• Food temperature must be monitored and must not exceed 70°F (21°C) during the 6-hour period.
• Maximum display duration: 6 hours.
• Food must be discarded immediately if its temperature exceeds 70°F at any point, or when the 6-hour limit is reached.

Mandatory TPHC Prerequisites: Written Standard Operating Procedures (SOPs) must be maintained on-site and approved by the regulatory authority, and containers must be clearly labeled with the exact start and discard times.