HACCP

Hazard Analysis and Critical Control Points (HACCP) for the Cannabis Industry: Part 4

By Kathy Knutson, Ph.D.
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HACCP

In Part 3 of this series on HACCP, Critical Control Points (CCPs), validation of CCPs and monitoring of CCPs were defined. When a HACCP plan identifies the correct CCP, validates the CCP as controlling the hazard and monitors the CCP, a potential hazard is controlled in the manufacturing and packaging of cannabis-infused edibles. The food industry is big on documentation. If it’s not documented, it did not happen. The written hazard analysis, validation study and monitoring of CCPs create necessary records. It is these records that will prove to a customer, auditor or inspector that the edible is safe. Here in Part 4, more recordkeeping is added on for deviation from a CCP, verification and a recall plan. 

Take Corrective Action When There Is a Deviation from a Critical Control Point

Your food safety team conducts a hazard analysis, identifies CCPs and decides on monitoring devices, frequency and who is responsible for monitoring. You create an electronic or paper record of the monitoring for every batch of edible to document critical limits were met. Despite all your good efforts, something goes wrong. Maybe you lose power. Maybe the equipment jams. Nothing is perfect when dealing with ingredients, equipment and personnel. Poop happens. Because you are prepared before the deviation, your employees know what to do. With proper training, the line worker knows what to do with the equipment, the in-process product and who to inform. In most cases the product is put on hold for evaluation, and the equipment is fixed to keep running. The choices for the product include release, rework or destroy. Every action taken needs to be recorded on a corrective action form and documents attached to demonstrate the fate of the product on hold. All the product from the batch must be accounted for through documentation. If the batch size is 100 lb, then the fate of 100 lb must be documented.

Verify Critical Control Points Are Monitored and Effective

First, verification and validation are frequently confused by the best of food safety managers. Validation was discussed as part of determining CCPs in Part 3. Validation proves that following a CCP is the right method for safety. I call validation, “one and done.” Validation is done once for a CCP; while verification is ongoing at a CCP. For example, the time and temperature for effective milk pasteurization is very well known and dairies refer to the FDA Pasteurized Milk Ordinance. Dairies do not have to prove over and over that a combination of time and temperature is effective (validation), because that has been proven.

I encourage you to do as much as you can to prepare for a recall.A CCP is monitored to prove the safety parameters are met. Pasteurization is an example of the most commonly monitored parameters of time and temperature. At a kill step like pasteurization, the employee at that station is responsible for accurate monitoring of time and temperature. The company managers and owners should feel confident that CCPs have been identified and data are being recorded to prove safety. Verification is not done by the employee at the station but by a supervisor or manager. The employee at the station is probably not a member of the food safety team that wrote the HACCP plan, but the supervisor or manager that performs verification may be. Verification is proving that what was decided by the food safety team is actually implemented and consistently done.

Verification is abundant and can be very simple. First, every record associated with a CCP is reviewed by a supervisor or manager, i.e. someone who did not create the record. This can be a simple initial and date at the bottom of the record. Every corrective action form with its associated evaluation is verified in the same way. When HACCP plans are reviewed, that is verification. Verification activities include 1) testing the concentration of a sanitizer, 2) reviewing Certificates of Analysis from suppliers, 3) a review of the packaging label and 4) all chemical and microbiological testing of ingredients and product. The HACCP plan identifies CCPs. Verification confirms that implementation is running according to the plan.

Verification is like a parent who tells their child to clean their room. The child walks to their room and later emerges to state that the room is clean. The parent can believe the word of the child, if the child has been properly trained and has a history of successfully cleaning their room. At some frequency determined by the parent, the room will get a parental visual check. This is verification. In the food industry, CCP monitoring records and corrective action must be reviewed within seven days after the record is created and preferably before the food leaves the facility. Other verification activities are done in a timely manner as determined by the company.

Food processing and sanitation
Product recalls due to manufacturing errors in sanitation cause mistrust among consumers.

Write a Recall Plan

In the food industry, auditors and FDA inspectors require a written recall plan. Mock recalls are recommended and always provide learning and improvement to systems. Imagine your edible product contains sugar, and your sugar supplier notifies you that the sugar is recalled due to glass pieces. Since you are starting with the supplier, that is one step back. Your documentation of ingredients includes lot numbers, dates and quantity of sugar.You keep good records and they show you exactly how much of the recalled lot was received. Next you gather your batch records. Batches with the recalled sugar are identified, and the total amount of recalled sugar is reconciled. You label every batch of your edible with a lot code, and you identify the amount of each affected lot and the customer. You have a press release template in which you add the specific information about the recall and affected lots. You notify every customer where the affected edible was shipped with a plan to return or destroy the edible. When you notify your customers, you go one step forward.

How would your company do in this situation? I have witnessed the difficulties a company faces in a recall when I was brought in to investigate the source of a pathogen. Food safety people in my workshops who have worked through a recall tell me that it was the worst time of their life. I encourage you to do as much as you can to prepare for a recall. Here are two good resources:

Please comment on this blog post below. I love feedback!

HACCP

Hazard Analysis and Critical Control Points (HACCP) for the Cannabis Industry: Part 3

By Kathy Knutson, Ph.D.
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HACCP

Parts One and Two in this series have defined Good Manufacturing Practices, introduced Hazard Analysis and Critical Control Points (HACCP) and explained the first HACCP step of hazard analysis. A food safety team will typically work from a flow diagram to identify biological, chemical or physical hazards at each step of processing and packaging. Once the hazard is identified, the severity and probability are debated. Hazards with severe consequences or high probability are carried through the HACCP plan as Critical Control Points (CCPs).

Critical Control Points definedHACCP is a do-it-yourself project.

Where exactly will the hazard be controlled? CCPs are embedded within certain steps in processing and packaging where the parameters, like temperature, must be met to ensure food safety. Failure at a CCP is called a deviation from the HACCP plan. The food safety team identifies where manufacturing problems could occur that would result in a product that could cause illness or injury. Not every step is a CCP! For example, I worked with a client that had several locations for filters of a liquid stream. The filters removed food particles, suspended particulates and potentially metal. We went through a virtual exercise of removing each filter one-by-one and talking through the result on controlling the potential hazard of metal. We agreed that failure of the final filter was the CCP for catching metal, but not the other filters. It was not necessary to label each filter as a CCP, because every CCP requires monitoring and verification.

Identification of a CCP starts more documentation, documentation, documentation.

Do you wish you had more reports to write, more forms to fill out, more data to review? No. Nobody wants more work. When a CCP is identified, there is more work to do. This just makes sense. If a CCP is controlling a hazard, you want to know that the control is working. Before I launch into monitoring, I digress to validation.

CCP validationThis is where someone says, “We have always done it this way, and we have never had a problem.”

You want to know if a critical step will actually control a hazard. Will the mesh of a filter trap metal? Will the baking temperature kill pathogens? Will the level of acid stop the growth of pathogens? The US had a major peanut butter recall by Peanut Corporation of America. There were 714 Salmonella cases (individuals) across 46 states from consumption of the contaminated peanut butter. Imagine raw peanuts going into a roaster, coming out as roasted peanuts and being ground into butter. Despite the quality parameters of the peanut butter being acceptable for color and flavor, the roasting process was not validated, and Salmonella survived. Baking of pies, pasteurization of juice and canning all rely on validated cook processes for time and temperature. Validation is the scientific, technical information proving the CCP will control the hazard. Without validation, your final product may be hazardous, just like the peanut butter. This is where someone says, “We have always done it this way, and we have never had a problem.” Maybe, but you still must prove safety with validation.

The hazard analysis drives your decisions.

Starting with the identification of a hazard that requires a CCP, a company will focus on the control of the hazard. A CCP may have one or more than one parameter for control. Parameters include time, temperature, belt speed, air flow, bed depth, product flow, concentration and pH. That was not an exhaustive list, and your company may have other critical parameters. HACCP is a do-it-yourself project. Every facility is unique to its employees, equipment, ingredients and final product. The food safety team must digest all the variables related to food safety and write a HACCP plan that will control all the hazards and make a safe product.

Meeting critical limits at CCPs ensures food safety

The HACCP plan details the parameters and values required for food safety at each CCP.The HACCP plan identifies the minimum or maximum value for each parameter required for food safety. A value is just a number. Imagine a dreadful day; there are problems in production. Maybe equipment stalls and product sits. Maybe the electricity flickers and oven temperature drops. Maybe a culture in fermentation isn’t active. Poop happens. What are the values that are absolutely required for the product to be safe? They are often called critical limits. This is the difference between destroying product and selling product. The HACCP plan details the parameters and values required for food safety at each CCP. In production, the operating limits may be different based on quality characteristics or equipment performance, but the product will be safe when critical limits are met. How do you know critical limits are met?

CCPs must be monitored

Every CCP is monitored. Common tools for monitoring are thermometers, timers, flow rate meters, pH probes, and measuring of concentration. Most quality managers want production line monitoring to be automated and continuous. If samples are taken and measured at some frequency, technicians must be trained on the sampling technique, frequency, procedure for measurement and recording of data. The values from monitoring will be compared to critical limits. If the value does not reach the critical limit, the process is out of control and food safety may be compromised. The line operator or technician should be trained to know if the line can be stopped and how to segregate product under question. Depending on the hazard, the product will be evaluated for safety, rerun, released or disposed. When the process is out of control, it is called a deviation from the HACCP plan.

A deviation initiates corrective action and documentation associated with the deviation. You can google examples of corrective action forms; there is no one form required. Basically, the line operator, technician or supervisor starts the paperwork by recording everything about the deviation, evaluation of the product, fate of the product, root cause investigation, and what was done to ensure the problem will not happen again. A supervisor or manager reviews and signs off on the corrective action. The corrective action form and associated documentation should be signed off before the product is released. Sign off is an example of verification. Verification will be discussed in more detail in a future article.

My thoughts on GMPs and HACCP were shared in a webinar on May 2nd hosted by CIJ and NEHA. Please comment on this blog post below. I love feedback!

HACCP

Hazard Analysis and Critical Control Points (HACCP) for the Cannabis Industry: Part 2

By Kathy Knutson, Ph.D.
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HACCP

HACCP is a food safety program developed in the 1960s for the food manufacturing industry, mandated for meat, seafood and juice and adopted by foodservice for the safe serving of meals at restaurants. With state requirements for the safe production of cannabis-infused products, namely edibles, facilities may be inspected against HACCP principles. The cannabis industry and state inspectors recognize the need for safe edible manufacture. Lessons can be learned from the food industry, which has advanced beyond HACCP plans to food safety plans, starting with procurement and including the shipment of finished product to customers.

In my work with the food industry, I write HACCP and food safety plans and deliver training on food safety. In Part 1 of this series, I wrote about the identification of hazards, which is the first step in HACCP plan development. Before we continue with the next HACCP step, I will discuss Good Manufacturing Practices (GMPs). GMPs are the foundation on which HACCP is built. In other words, without GMPs in place, the facility will not have a successful HACCP program. GMPs are required in the food, dietary supplement and pharmaceutical industries, all under the enforcement of the federal Food and Drug Administration (FDA). Without federal regulation for cannabis edible manufacture, there may not be state-mandated requirements for GMPs. Let me warn you that any food safety program will not succeed without proper control of GMPs.HACCP

GMPs cover all of your programs and procedures to support food safety without having a direct, instant control. For example, when brownies are baked as edibles, food safety is controlled by the time and temperature of baking. A written recipe and baking procedure are followed for the edible. The time and temperature can be recorded to provide documentation of proper baking. In the food industry, this is called a process preventative control, which is critical to food safety and is part of a HACCP plan. Failure of proper time and temperature of baking not only leads to an unacceptable product in terms of quality, but results in an unsafe product that should not be sold.

Back to GMPs. Now think of everything that was done up to the steps of mixing and baking. Let’s start with personnel. Facilities for edibles have hiring practices. Once an employee is hired, the employee is trained, and training will include food safety procedures. When working at the job after training, the employee measuring ingredients will demonstrate proper grooming and hand washing. Clean aprons, hairnets, beard nets and gloves will be provided by the facility and worn by the employee. The same goes for the employee that bakes and the employee that packages the edible. One category of GMPs is Personnel.

Edibles facilities are not foodservice; they are manufacturing. A second GMP category is cleaning and sanitizing. Food safety is controlled through proper cleaning and sanitizing of food contact surfaces (FCS). The edible facility will have in place the frequency and methods for cleaning all parts of the facility- outside, offices, restrooms, break room and others. GMPs cover the general cleaning procedures and procedures for cleaning receiving, storage; what we would consider processing to include weighing, process steps and packaging; finished product storage and shipping. Management of the facility decides the methods and frequency of cleaning and sanitizing with greater care given to processing. Without proper cleaning and sanitizing, a facility cannot achieve food safety.

I could go on and on about GMPs. Other GMPs include water safety, integrity of the buildings, pest control program, procurement, sewage disposal and waste disposal. Let’s transition back to HACCP. In Part 1 of this series, I explained identification of hazards. Hazards are one of three types: biological, chemical and physical.

At this point, I am not surprised if you are overwhelmed. After reading Part 1 of this series, did you form a food safety team? At each edibles facility, there should be at least one employee who is trained externally in food safety to the standard that foodservice meets. Classes are offered locally and frequently. When the facility is ready, the next step of training is a HACCP workshop for the food industry, not foodservice. Edibles facilities are not foodservice; they are manufacturing. Many colleges and associations provide HACCP training. Finally, at the least, one employee should attend a workshop for Preventive Controls Qualified Individual.

To institute proper GMPs, go to ConnectFood.com for a GMP checklist. Did you draw up a flow diagram after reading Part 1? With a flow diagram that starts at Receiving and ends at Shipping, the software at ConnectFood.com takes you through the writing steps of a HACCP or food safety plan. There are many resources out there for GMPs, so it can get overwhelming. ConnectFood.com is my favorite resource.

The next step in HACCP development after identification of hazards is to identify the exact step where the hazard will be controlled. Strictly speaking, HACCP only covers process preventive controls, which typically start with a weigh step and end with a packaging step. A facility may also have a step where temperature must be controlled for food safety, e.g. cooling. In HACCP, there are commonly two process preventive controls:

  • Biological hazard of Salmonella and Escherichia coli: the heat step
  • Physical hazard of metal: metal detector

Strictly speaking, HACCP does not include cleaning, sanitizing and supplier approval for procurement of ingredients and packaging. I hope you see that HACCP is not enough. There have been hundreds of recalls and outbreaks due to problems in non-processing steps. The FDA requires food manufactures to go beyond HACCP and follow a written food safety plan, which includes hazards controlled at these steps:

  • Biological hazard of Listeria monocytogenes: cleaning and sanitizing of the processing environment and equipment
  • Physical hazards coming in with ingredients: supplier approval
  • Physical hazard of glass and hard plastic: Here I am thinking of glass breaking or plastic pieces flying off buckets. This is an internal hazard and is controlled by following written procedures. The written document is a Standard Operating Procedure (SOP).
  • Chemical hazard of pesticides: supplier approval
  • Chemical hazard of mycotoxins: supplier approval
  • Chemical hazard of allergens: supplier approval, label check at Receiving and product labeling step

Does a cannabis edible facility honestly not care or not control for pesticides in ingredients because this is not part of HACCP? No. There are two ways for procurement of ingredients in which pesticides are controlled. Either the cannabis cultivation is controlled as part of the samebusiness or the facility works with a supplier to confirm the ingredient meets pesticide tolerances. Strictly speaking, this control is not part of HACCP. For this and many other reasons, HACCP is a good place to start the control of food safety when built on a solid foundation of GMPs. In the same way the food industry is required to go beyond HACCP with a food safety plan, the cannabis industry must go beyond HACCP.

My thoughts will be shared in a webinar on May 2nd hosted by CIJ and NEHA. I encourage you to listen in to continue this discussion.Please comment on this blog post below. I love feedback!

HACCP

Hazard Analysis and Critical Control Points (HACCP) for the Cannabis Industry: Part 1

By Kathy Knutson, Ph.D.
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HACCP

Hazard Analysis and Critical Control Points (HACCP) Defined

Farm-to-fork is a concept to describe the control of food safety starting in the fields of a farm and ending with deliciousness in my mouth. The more that is optimized at every step, the more food safety and quality are realized. Farm-to-fork is not a concept reserved for foodies or “eat local” food campaigns and applies to all scales of food manufacture. HACCP is like putting the last piece of a huge puzzle in the middle and seeing the whole picture develop. HACCP is a program to control food safety at the step of food processing. In states where cannabis is legal, the state department of public health or state department of agriculture may require food manufacturers to have a HACCP plan. The HACCP plan is a written document identifying food safety hazards and how those hazards are controlled by the manufacturer. While there are many resources available for writing a HACCP plan, like solving that puzzle, it is a do-it-yourself project. You can’t use someone else’s “puzzle,” and you can’t put the box on a shelf and say you have a “puzzle.”

HACCP is pronounced “ha” as in “hat” plus “sip.”

(Say it aloud.)

3-2-1 We have liftoff.

The history of HACCP starts not with Adam eating in the garden of Eden but with the development of manned missions to the moon, the race to space in the 1950s. Sorry to be gross, but imagine an astronaut with vomiting and diarrhea as a result of foodborne illness. In the 1950s, the food industry relied on finished product testing to determine safety. Testing is destructive of product, and there is no amount of finished product testing that will determine food is safe enough for astronauts. Instead, the food industry built safety into the process. Temperature was monitored and recorded. Acidity measured by pH is an easy test. Rather than waiting to test the finished product in its sealed package, the food industry writes specifications for ingredients, ensures equipment is clean and sanitized, and monitors processing and packaging. HACCP was born first for astronauts and now for everyone.HACCP

HACCP is not the only food safety program.

If you are just learning about HACCP, it is a great place to start! There is a big world of food safety programs. HACCP is required by the United States Department of Agriculture for meat processors. The Food and Drug Administration (FDA) requires HACCP for seafood processing and 100% juice manufacture. For all foods beyond meat, seafood and juice, FDA has the Food Safety Modernization Act (FSMA) to enforce food safety. FSMA was signed in 2011 and became enforceable for companies with more than 500 employees in September of 2016; all food companies are under enforcement in September 2018. FSMA requires all food companies with an annual revenue greater than $1 million to follow a written food safety plan. Both FDA inspectors and industry professionals are working to meet the requirements of FSMA. There are also national and international guidelines for food safety with elements of HACCP which do not carry the letter of law.

The first step in HACCP is a hazard analysis.

Traditionally HACCP has focused on processing and packaging. Your organization may call that manufacturing or operations. In a large facility there is metering of ingredients by weight or volume and mixing. A recipe or batch sheet is followed. Most, but not all, products have a kill step where high heat is applied through roasting, baking, frying or canning. The food is sealed in packaging, labeled, boxed and heads out for distribution. For your hazard analysis, you identify the potential hazards that could cause injury or illness, if not controlled during processing. Think about all the potential hazards:

  • Biological: What pathogens are you killing in the kill step? What pathogens could get in to the product before packaging is sealed?
  • Chemical: Pesticides, industrial chemicals, mycotoxins and allergens are concerns.
  • Physical: Evaluate the potential for choking hazards and glass, wood, hard plastic and metal.

The hazards analysis drives everything you do for food safety.

I cannot emphasize too much the importance of the hazard analysis. Every food safety decision is grounded in the hazard analysis. Procedures will be developed and capital will be purchased based on the hazard analysis and control of food safety in your product. There is no one form for the completion of a hazard analysis.

HACCP risk matrix
A risk severity matrix. Many HACCP training programs have these.

So where do you start? Create a flow diagram naming all the steps in processing and packaging. If your flow diagram starts with Receiving of ingredients, then the next step is Storage of ingredients; include packaging with Receiving and Storage. From Storage, ingredients and packaging are gathered for a batch. Draw out the processing steps in order and through to Packaging. After Packaging, there is finished product Storage and Distribution. Remember HACCP focuses on the processing and packaging steps. It is not necessary to detail each step on the flow diagram, just name the step, e.g. Mixing, Filling, Baking, etc. Other supporting documents have the details of each step.

For every step on the flow diagram, identify hazards.

Transfer the name of the step to the hazard analysis form of your choice. Focus on one step at a time. Identify biological, chemical and physical hazards, if any, at that step. The next part is tricky. For each hazard identified, determine the probability of the hazard occurring and severity of illness or injury. Some hazards are easy like allergens. If you have an ingredient that contains an allergen, the probability is high. Because people can die from ingestion of allergens when allergic, the severity is high. Allergens are a hazard you must control. What about pesticides? What is the probability and severity? I can hear you say that you are going to control pesticides through your purchasing agreements. Great! Pesticides are still a hazard to identify in your hazard analysis. What you do about the hazard is up to you.

Microbiology 101 Part Two

By Kathy Knutson, Ph.D.
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Microbiology 101 Part One introduced the reader to the science of microbiology and sources of microbes. In Part Two, we discuss the control of microorganisms in your products.

Part 2

The cannabis industry is probably more informed about patients and consumers of their products than the general food industry. In addition to routine illness and stress in the population, cannabis consumers are fighting cancer, HIV/AIDS and other immune disorders. Consumers who are already ill are immunocompromised. Transplant recipients purposely have their immune system suppressed in the process of a successful transplant. These consumers have pre-existing conditions where the immune system is weakened. If the immunocompromised consumer is exposed to viral or bacterial pathogens through cannabis products, the consumer is more likely to suffer from a viral infection or foodborne illness as a secondary illness to the primary illness. In the case of consumers with weakened immune systems, it could literally kill them.Bacteria, yeast, and mold are present in all environments.

The cannabis industry shoulders great responsibility in both the medical and adult use markets. In addition to avoiding chemical hazards and determining the potency of the product, the cannabis industry must manufacture products safe for consumption. There are three ways to control pathogens and ensure a safe product: prevent them from entering, kill them and control their growth.

Prevent microorganisms from getting in

Think about everything that is outdoors that will physically come in a door to your facility. Control the quality of ingredients, packaging, equipment lubricants, cleaning agents and sanitizers. Monitor employee hygiene. Next, you control everything within your walls: employees, materials, supplies, equipment and the environment. You control receiving, employee entrance, storage, manufacturing, packaging and distribution. At every step in the process, your job is to prevent the transfer of pathogens into the product from these sources.

Kill microorganisms

Colorized low-temperature electron micrograph of a cluster of E. coli bacteria.
Image courtesy of USDA ARS & Eric Erbe

The combination of raw materials to manufacture your product is likely to include naturally occurring pathogens. Traditional heat methods like roasting and baking will kill most pathogens. Remember, sterility is not the goal. The concern is that a manufacturer uses heat to achieve organoleptic qualities like color and texture, but the combination of time and temperature may not achieve safety. It is only with a validated process that safety is confirmed. If we model safety after what is required of food manufacturers by the Food and Drug Administration, validation of processes that control pathogens is required. In addition to traditional heat methods, non-thermal methods for control of pathogens includes irradiation and high pressure processing and are appropriate for highly priced goods, e.g. juice. Killing is achieved in the manufacturing environment and on processing equipment surfaces after cleaning and by sanitizing.

If you have done everything reasonable to stop microorganisms from getting in the product and you have a validated step to kill pathogens, you may still have spoilage microorganisms in the product. It is important that all pathogens have been eliminated. Examples of pathogens include Salmonella, pathogenic Escherichia coli, also called Shiga toxin-producing E. coli (STEC) and Listeria monocytogenes. These three common pathogens are easily destroyed by proper heat methods. Despite steps taken to kill pathogens, it is theoretically possible a pathogen is reintroduced after the kill step and before packaging is sealed at very low numbers in the product. Doctors do not know how many cells are required for a consumer to get ill, and the immunocompromised consumer is more susceptible to illness. Lab methods for the three pathogens mentioned are designed to detect very low cell numbers. Packaging and control of growth factors will stop pathogens from growing in the product, if present.

Control the growth of microorganisms

These growth factors will control the growth of pathogens, and you can use the factors to control spoilage microbes as well. To grow, microbes need the same things we do: a comfortable temperature, water, nutrients (food), oxygen, and a comfortable level of acid. In the lab, we want to find the pathogen, so we optimize these factors for growth. When you control growth in your product, one hurdle may be enough to stop growth; sometimes multiple hurdles are needed in combination. Bacteria, yeast, and mold are present in all environments. They are at the bottom of the ocean under pressure. They are in hot springs at the temperature of boiling water. The diversity is immense. Luckily, we can focus on the growth factors for human pathogens, like Salmonella, pathogenic E. coli, and Listeria monocytogenes.

The petri dishes show sterilization effects of negative air ionization on a chamber aerosolized with Salmonella enteritidis. The left sample is untreated; the right, treated. Photo courtesy of USDA ARS & Ken Hammond

Temperature. Human pathogens prefer to grow at the temperature of the human body. In manufacture, keep the time a product is in the range of 40oF to 140oF as short as possible. You control pathogens when your product is at very hot or very cold temperatures. Once the product cools after a kill step in manufacturing, it is critical to not reintroduce a pathogen from the environment or personnel. Clean equipment and packaging play key roles in preventing re-contamination of the product.

Water. At high temperatures as in baking or roasting, there is killing, but there is also the removal of water. In the drying process that is not at high temperature, water is removed to stop the growth of mold. This one hurdle is all that is needed. Even before mold is controlled, bacterial and yeast growth will stop. Many cannabis candies are safe, because water is not available for pathogen growth. Packaging is key to keep moisture out of the product.

Nutrients. In general, nutrients are going to be available for pathogen growth and cannot be controlled. In most products nutrients cannot be removed, however, recipes can be adjusted. Recipes for processed food add preservatives to control growth. In cannabis as in many plants, there may be natural compounds which act as preservatives.

Oxygen. With the great diversity of bacteria, there are bacteria that require the same oxygen we breathe, and mold only grows in oxygen. There are bacteria that only grow in the absence of oxygen, e.g. the bacteria responsible for botulism. And then there are the bacteria and yeast in between, growing with or without oxygen. Unfortunately, most human pathogens will grow with or without oxygen, but slowly without oxygen. The latter describes the growth of Salmonella, E. coli, and Listeria. While a package seals out air, the growth is very slow. Once a package is opened and the product is exposed to air, growth accelerates.

Acid. Fermented or acidified products have a higher level of acid than non-acid products; the acid acts as a natural preservative. The more acid, the more growth is inhibited. Generally, acid is a hurdle to growth, however and because of diversity, some bacteria prefer acid, like probiotics which are non-pathogenic. Some pathogens, like E. coli, have been found to grow in low acid foods, e.g. juice, even though the preference is for non-acidic environments.

Each facility is unique to its materials, people, equipment and product. A safe product is made by following Good Agricultural Practices for the cannabis, by following Good Manufacturing Practices and by suppressing pathogens by preventing them coming in, killing them and controlling their growth factors. Future articles will cover Hazard Analysis and Critical Control Points (HACCP) and food safety in more detail.

Microbiology 101 Part One

By Kathy Knutson, Ph.D.
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I have been studying microorganisms for over 35 years, and the elusive critters still fascinate me! Here in Microbiology 101, I write about the foundation of knowledge on which all microbiologists build. You may have a general interest in microbiology or have concerns in your operation. By understanding microbiology, you understand the diversity of microorganisms, their source, control of microorganisms and their importance.

Part 1

The term microbiology covers every living being we cannot see with the naked eye. The smallest microbe is a virus. Next in size are the bacteria, then yeast and mold cells, and the largest microbes are the protozoans. The tiny structure of a virus may be important in the plant pathology of cannabis, but will not grow in concentrates or infused products. A virus is not living, until it storms the gate of a living cell and overtakes the functions within the cell. Viruses are the number one cause of foodborne illness, with the number one virus called Norovirus. Think stomach flu. Think illness on cruise ships. Viruses are a food service problem and can be prevented by requiring employees to report sickness, have good personal hygiene including good hand washing, and, as appropriate, wear gloves. Following Good Manufacturing Practices (GMPs) is critical in preventing the transfer of viruses to a product where the consumer can be infected.

The petri dishes show sterilization effects of negative air ionization on a chamber aerosolized with Salmonella enteritidis. The left sample is untreated; the right, treated. Photo courtesy of USDA ARS & Ken Hammond

The largest microbial cell is the protozoan. They are of concern in natural water sources, but like viruses, will not grow in cannabis products. Control water quality through GMPs, and you control protozoans. Viruses and protozoans will not be further discussed here. Bacteria, yeast and mold are the focus of further discussion. As a food microbiologist, my typical application of this information is in the manufacturing of food. Because Microbiology 101 is a general article on microbiology, you can apply the information to growing, harvesting, drying, manufacture of infused products and dispensing.

It is not possible to have sterile products. Even the canning process of high temperature for an extended time allows the survival of resistant bacterial spores. Astronauts take dehydrated food into space, and soldiers receive MREs; both still contain microbes. Sterility is never the goal. So, what is normal? Even with the highest standards, it is normal to have microbes in your products. Your goal is to eliminate illness-causing microorganisms, i.e. pathogens. Along the way, you will decrease spoilage microbes too, making a product with higher quality.

Petri dish containing the fungus Aspergillus flavus. It produces carcinogenic aflatoxins, which can contaminate foods and cause an invasive fungal disease.
Photo courtesy of USDA ARS & Peggy Greb.

Yeast and mold were discussed on CIJ in a previous article, Total Yeast & Mold Count: What Cultivators & Business Owners Need to Know. Fuzzy mold seen on the top of food left in the refrigerator too long is a quality issue, not a safety issue. Mold growth is a problem on damaged cannabis plants or cuttings and may produce mycotoxin, a toxic chemical hazard. Following Good Agricultural Practices (GAPs) will control mold growth. Once the plant is properly dried, mold will not grow and produce toxin. Proper growing, handling and drying prevents mycotoxins. Like mold, growth of yeast is a quality issue, not a safety issue. As yeast grow, they produce acid, alcohol and carbon dioxide gas. While these fermentation products are unwanted, they are not injurious. I am aware that some states require cannabis-infused products to be alcohol-free, but that is not a safety issue discussed here.

What are the sources of microorganisms?

People. Employees who harvest cannabis may transfer microorganisms to the plant. Later, employees may be the source of microbes at the steps of trimming, drying, transfer or portioning, extract processing, infused product manufacture and packaging.

Ingredients, Supplies and Materials. Anything you purchase may be a source of microorganisms. Procure quality merchandise. Remember the saying, “you get what you pay for.”

Environment. Starting with the outdoors, microbes come from wind, soil, pests, bird droppings and water. When plants are harvested outdoors or indoors, microbes come from the tools and bins. Maintain clean growing and harvesting tools in good working condition to minimize contamination with microbes. For any processing, microbes come from air currents, use of water, and all surfaces in the processing environment from dripping overhead pipes to floor drains and everything in between.

In Part 2 I will continue to discuss the diversity of microorganisms, and future articles will cover Hazard Analysis and Critical Control Points (HACCP) and food safety in more detail. What concerns do you have at each step of operations? Are you confident in your employees and their handling of the product? As each state works to ensure public health, cannabis-infused products will receive the same, if not more, scrutiny as non-cannabis food and beverages. With an understanding and control of pathogens, you can focus on providing your customers with your highest quality product.