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Simplifying Food Regulation


FDA Reader: Simplifying Food Regulation

Posts tagged Food Safety
Low Acid Foods Packaged in Hermetically Sealed Containers

What You Need to Know:

  • They are commonly referred to as low-acid-canned-foods (or "LACF") even though they may not be packaged in a can.

  • Low Acid Foods in Hermetically Sealed Containers are by definition (1) shelf stable, (2) heat-treated (3) have a pH of >4.6 and (4) a water activity of 0.85

  • Examples of Low Acid Foods in Hermetically Sealed Containers include: shelf-stable milk in pouches, canned beans, vegetable broth in a pouch.

  • There are 2 primary methods for processing LACF: Using a Retort (pressuring cooker) and Aseptic Processing (a sterile packaging process)

  • They are regulated in 21 CFR Part 113: Thermally Processed Low Acid Foods Packaged in Hermetically Sealed Containers

Key Terms

Low Acid Foods have a pH of >4.6 and a water activity of >0.85

Hermetically Sealed Container is packaging which prevents the entry of microorganisms and maintains the commercial sterility of the contents.

Commercial Sterility means there is zero microbiological activity (including bacteria, spores or anything that could reproduce under shelf-stable conditions

LACF ("Low-Acid-Canned-Food"): This term is used interchangeably with "Low Acid Foods Packaged in Hermetically Sealed Containers". It may apply to foods packaged in containers other than cans (i.e. flexible pouches or jars) which is why the term "hermetically sealed container" is used.

Examples of Low Acid Canned Foods:

This list only includes food products that would be governed under the FDA. Foods that fit the definition of LACF and contain >2% meat content are governed under the USDA.

  • shelf-stable milk (commonly packaged in pouches)

  • Canned tuna

  • Canned black beans

  • Canned corn

  • Canned mushrooms

  • Canned Cauliflower

  • Shelf-stable vegetable broth

Does Part 113 Apply to your food product?

Is my product a Low-Acid-Canned-Food (LACF)?

Even if your product is not "canned", it may fall under the regulation of Part 113. Use the flow (above) to the right to determine whether your product is considered a LACF (aka "low acid food in a hermetically sealed container")

Requirements for Producers of LACF


The operators of a processing system that produces LACF must have attended an FDA approved course that instructs on how to safely process these foods. An example of an approved course is "The Better Process Control School" which is offered online or in person.

Source: Part 113.40

Equipment and Procedures

The bulk of regulation under Part 113 relates to the requirements for thermal processing and aseptic processing.

Methods for Processing LACF

The two primary methods for processing low-acid-canned-foods are retort and aseptic processing.


A retort is a large pressure cooker. Sealed containers of food (typically cans, jars, or pouches) are loaded into the retort and heated using steam and pressure. This thermal treatment kills all of the microbiological activity in the containers.

In a retort process, products are treated after they are packaged and sealed.

The use of high pressure allows the retort to achieve temperatures above boiling, which allows for products to rapidly achieve sterility.

Examples of Foods Processed by Retort: Canned beans, canned vegetables, canned soup, canned tuna

Aseptic Processes

In an aseptic process, the food products are heat processed prior to packaging. Since there is a risk that the packaging or food may become contaminated in the packaging step, the entire process takes place under sterile conditions (hence the term aseptic).

Aseptic manufacturing requires tremendous control to maintain a sterile environment during processing. The machinery to perform this type of process is typically very expensive.

Examples of Foods Processed by Aseptic Process: Shelf-Stable Milk, juice boxes

Exemptions for Producers of Low Acid Canned Foods (LACF)

Processors who operate under Part 113 are exempt from the following requirements:

  • Subpart C (Hazard Analysis and Risk Based Preventive Controls)

  • Subpart G Supply Chain Controls

However, this exemption only applies in regards to microbiological hazards regulated under Part 113. Simply -- if the food processor identifies chemical or physical hazards in their production process, they must address those hazards as they are outlined in Subpart C.

Additionally, if the processor identifies a hazard that requires a supplier-applied preventive control, then the processor would have to conduct supplier verification activities as described in Subpart G.

Source: Part 117.5 (d) (1) & (2)


Are fermented foods regulated under Part 113?

If the fermented food has a pH of >4.6 and a water activity > 0.85, then it is considered a "low-acid-canned food" (LACF) and is regulated under Part 113.

If the fermented food has a pH of <4.6 then it is not regulated as a Low-Acid-Canned-Food (Part 113) OR an acidified food (Part 114).

Are Alcoholic Beverages Regulated Under Part 113?

No. Alcoholic beverages are not regulated under Part 113 (Low Acid Foods in Hermetically Sealed Containers) or Part 114 (Acidified Foods).


21 CFR Part 113 -- Thermally Processed Low Acid Foods Packaged in Hermetically Sealed Containers

What is a "Kill Step" in Food Safety?

What does a “Kill Step” or "Lethality Step" mean in Food Safety?

When I was first managing a commissary producing 10,000 meals per day, our engineer was always talking about the “kill step.” I never knew what he was talking about but I have since realized it is one of the most important steps in food safety.

Most efforts we take in food safety are related to harmful bacteria. And most efforts are related to minimizing (but not stopping) the growth of harmful bacteria.

A strategy that minimizes bacteria growth is refrigeration. Most bacteria can’t reproduce quickly in cold, but they still reproduce, albeit at a slow rate. This is the reason that perishable food doesn't last indefinitely in the fridge. Of course, without refrigeration, bacteria grows quickly at room temperature and we intuitively know this is bad (i.e.leftover chicken left out overnight).

The most important thing to remember is this: if you leave food on the counter overnight and then put it back in the fridge, it won’t kill the bacteria that grew while it was sitting out, it’ll just slow down the growth process from the moment you put it back in the fridge.

This graph should help illustrate what I mean:

Food Safety Chicken Bacteria pt 1.jpg

What's Happening in this Graph?

1. You have chicken leftovers in the fridge. There is some bacteria in the leftovers, but it is still safe to eat. You can also see that bacteria growth is slow during these periods because of the cold.

2. You accidentally leave the leftovers on the counter overnight. Eek! We can see by the steepness of the line that bacteria count is growing RAPIDLY during this time, because bacteria are happy and reproduce quickly at room temperature.

3. In the morning, you see that you left the leftovers out all night. At this point, the bacteria level is unsafe to eat, but you put them back into the fridge anyway. While this slows down the growth rate of the bacteria, there is still an unsafe amount of bacteria in the chicken. Remember the refrigeration slows down bacteria growth rates, but it does not kill existing bacteria. So why did you put it back into the fridge? (keep reading!).

4. At lunch, you throw the chicken into the microwave and nuke it for 4 minutes, remembering that you left it out all night on the counter. This, my friend, is the kill step. Cooking (in this case, chicken) to 165º F doesn't slow bacteria growth, it actually kills all of the bacteria that already grew on the chicken.  At 165º only 1 in 100,000 Salmonella bacteria will survive. We call this a "Log 5" reduction because it reduces the count by 5 zeros. In effect, it "resets the clock" and makes the food safe to eat again. we see on the graph that the bacteria count plummets to almost nothing.

5. The leftovers are so goddamn hot that you went to write a blog post and forgot all about lunch for an hour. During this time, the leftovers cooled down to about room temperature, which triggered rapid bacteria growth. However, because you killed almost all of the salmonella bacteria in the leftovers, the total bacteria count remains low, despite exponential growth rates. It's still safe to eat even though it sat out at room temperature. This is fairly intuitive.

6. You remember the food and eat your (lukewarm) lunch. It tastes good and you didn't expose yourself to any food safety risk.


What Did We Learn?

  • Cooking/Reheating food ("The kill step") drastically reduces harmful levels of bacteria and makes it safe to eat.

  • Slow bacteria growth doesn't necessarily mean the food is safe to eat (as in step #3). Putting food with unsafe levels of bacteria in the refrigerator won't kill the pre-existing bacteria.

  • Fast bacteria growth doesn't necessarily mean food is unsafe to eat, as in Step #6. Think about your elementary school lunchbox (not refrigerated!). It's OK to have rapid bacteria growth for short amounts of time IF you're starting with a low bacteria count OR if there's a kill step after.

OK, So What is a Kill Step?

Here are some examples of "Kill Steps" used to reduce bacteria counts in food production:

  • Cooking

  • Use of chemicals: For example, using anti-microbial produce wash reduces bacteria counts in vegetables that will be served raw.

  • Pasteurization: heating something up without meaningfully changing it's composition to kill bacteria

  • Freezing: The majority of fish intended for raw consumption is frozen for a period of 7 days to kill harmful parasites. Note that freezing isn’t effective as a kill step against bacteria.

It's important to remember that different microorganisms have different tolerances for specific treatments. Another way of saying this is: what would kill a human may not kill a cockroach (and visa versa in some cases).  Freezing kills specific parasites present in raw fish, but it doesn't kill Listeria Monocytogenes, it just slows down the growth rate. Depending on the food being manufactured, multiple kill steps may be used to address different hazards in the production process.

What Happens When You Don't Use a Kill Step

Almost all food production operations use a kill step. The reason is because we don't know the preexisting microorganism counts when we receive a product in our facility. For example, we don't know whether the vegetables that we serve raw had safe or unsafe levels of E. Coli in them when they were purchased from our supplier.  Even if our process implies good food handling practices and low bacteria growth, we still may be putting our customers at risk because our supplier did not take precautions. This graph explains the risk we take on when we don't have a kill step:

Bacteria Growth with no Kill Step.jpg

It's impossible to know the level of bacteria growth in a purchased ingredient without conducting expensive lab tests. What we can do is choose reputable suppliers, take the temperature of incoming deliveries to confirm they weren't mishandled in transport, and include a kill step in our production process. By including a kill step in our process, we are not relying on our suppliers to have a 0.00% error rate.

Bacteria Growth with A Kill Step.jpg

In order to eliminate that risk, we include a kill step so we know our food is safe to deliver to customers, even if we received unsafe products from a supplier.

So What's the Kill Step in My Process?

Before you pick a kill step, you need to be aware of what specific microorganisms are found in the foods you produce. The good news is that specific types of harmful bacteria only exist in specific food groups, so if you make raspberry jam, you don't need to worry about bacteria that lives in shellfish. You can look up what types of bacteria exist in the food you produce in this FDA Training Manual on page 485-486.

Once you know what the hazards exist in your process, you can investigate what is an appropriate kill step and implement it.

Do you use a kill step in your production? Comment below

My $250,000 Lesson in Food Safety

I had been managing a 20k square foot food manufacturing facility for 8 days when we were inspected and shut down by the local health department.

I was terrified when the inspectors arrived. What were they looking for? What would they discover that I was unaware of? This is a fear that many restaurant owners and food producers are familiar with.

I made 3 mistakes that closed our business for 4 days and cost the company $250k, excluding lost revenue.

Mistake #1: Everything is OK Because This is How We’ve Always Done It

My predecessor had twenty years experience managing food establishments. When I took over, I trusted everything was operating according to the regulations and maintained the same standard. Employees washed their hands, wore gloves, and we had a team of porters cleaning the space every night. No report of food poisoning was ever traced back to our operations.

So everything is OK, right? [winces and pushes these concerns into the back of your mind]

Mistake #2: It Is Not Our Responsibility

The fruit flies that settled on our ceiling hadn’t come from our space. They had been living in the building-wide compost bins, which was situated outside of our space, albeit directly under our kitchen. We had fly traps in place and we had written the building 2 emails about the problem already.

Food producers tell me the same thing about their suppliers: “It’s their responsibility to make sure there is no safety risk in the chicken/flour/produce/glassware they sell us.”

Really?! Would you bet a quarter million dollars and your business’ reputation on it?

Mistake #3: Food Safety is Complicated and Something I Can Ignore Until We Get Bigger

Ugh. I am really talented at avoiding things that seem daunting. Plus, food safety regulations are really long and boring.

So I covered my eyes and ears and sang to myself at the top of my lungs. I told myself I’d fix the problems when we had more resources and when we were big enough to matter.

Have you ever told yourself any of these things?

THERE IS GOOD NEWS: you don’t need to know everything about food safety to ace 3rd party audits, and scale operations to millions of dollars in sales. In fact, most food establishments only need to control 1-3 hazards.

I will teach you to achieve food safety excellence without changing your operations, incurring huge costs, or taking up your time.

What part of food safety worries you? Post in the comments.