The recent recall of a popular salad dressing due to undeclared allergens highlights the vital importance of following facility policies in food manufacturing and packaging plants. Errors involving product contamination (48 percent), misbranding (27 percent), and undeclared allergens (16 percent) remain the three leading causes of food recalls.1 The good news is that many ingredient- and allergen-related incidents are preventable if plant employees receive and understand the proper training.

Allergen- and gluten-related recalls of products typically come down to two causes: intentional and unintentional adulteration. In cases of intentional adulteration, a person or business intentionally transfers an allergen or other gluten grain [rye, barley, or wheat—the latter of which is already classified as an allergen by the U.S. Food and Drug Administration (FDA)] into a product that is not supposed to have these ingredients, causing a major threat to consumers. The main reason a business may commit this act of food fraud is for economic gain. An example of intentional adulteration occurred in 2015 when ground peanut shells were added to packaged cumin spice. Fortunately, plants today typically have a food defense program in place to prevent this kind of adulteration. When a low-risk ingredient is found to be adulterated, it is important to institute policies to protect at-risk consumers. 

By contrast, unintentional adulteration can occur when, for example, a manufacturer makes a claim that a product is gluten-free, and employees do not follow good manufacturing practices (GMPs) or labeling is not properly reviewed. Breakdowns in protocol may involve failing to wash hands after consuming foods that contain gluten, wearing smocks during meal breaks, and bypassing beard nets on the production line. These risks are increased when staff rotate from production lines that package food containing gluten to lines that package gluten-free products.

Warehousing, ingredient staging, and weighing are other areas for allergen and gluten concerns. Many facilities use dedicated weighing utensils or disposable scoops to avoid mixing even minute amounts. A good practice is to double-bag partial bags of ingredients being returned to ingredient storage. 

Essential Elements of an Effective Training Program

Since employees are the cornerstone for preventing allergen and gluten adulteration, providing proper training to staff can prevent errors that could lead to a recall. An effective training program for gluten-free manufacturing also includes proper procedures for labeling gluten-free products and double-checking packages during quality assurance. Of course, training must also address personal hygiene skills, such as handwashing, which should be done with a surfactant, using sufficient mechanical pressure for at least 20 seconds. FDA's Health and Personal Hygiene Handbook,2 which includes standard protocol for the food manufacturing industry, is available on FDA's website.

The Food Allergy Safety, Treatment, Education, and Research (FASTER) Act was signed into law in 2021. Effective January 1, 2023, the Act adds sesame to the list of major food allergens. With this change taking effect, now is the perfect time to include rye and barley in allergen training as controlled ingredients (in addition to wheat, which is already listed). Hybrids of these grains are considered to be gluten containing, the most common being triticale, a rye-wheat blend and not a common ingredient. 

Training for the manufacturing of gluten-free products must have a protocol that defines sources of gluten and celiac disease, which affects more than 3 million Americans, along with non-celiac gluten sensitivity, impacting up to 6 percent of the U.S. population. During this focused training, it is important to dispel the misconception that anyone can eat a small amount of gluten without suffering adverse effects. While it might be possible for people who adopt a gluten-free diet as a lifestyle choice to eat gluten on occasion, people diagnosed with celiac disease may become extremely sick. Permanent damage from eating even a tiny amount of gluten is an area of concern, as up to 40 percent of people with celiac disease do not have gastrointestinal complaints with gluten ingestion. 

Addressing decontamination procedures is another essential element of a comprehensive training program for gluten-free product manufacturing. Employees should receive instruction on the steps for decontaminating themselves. Decontamination should occur whenever an employee returns from a meal, whether that meal is taken in the onsite breakroom or consumed offsite at a restaurant. In non-dedicated facilities, employees should decontaminate whenever they rotate jobs from a production line that packages products containing gluten to a production line that packages gluten-free foods. 

In addition to handwashing protocol, training on decontamination should address changing protective clothing, such as smocks, hair and beard nets, and shoe coverings, where required by the facility's risk management plan. Enforce facility policies to never take smocks home to launder. The facility is responsible for providing clean, non-disposable protective clothing. Another best practice is to use color-coded hair nets or other clothing for employees who work with gluten-free products in non-dedicated facilities.

More Training Basics

It might be tempting to limit training to production line staff, but anyone who accesses the facility, from production line employees to contractors and auditors, should participate. To be truly effective, training should be top-down so that everyone, including corporate executives, follow the same personal hygiene protocol. Those who complete the training, and those visiting, should read and sign an acknowledgement of requirements. This applies whether the plant is a two-person shop or a facility with 2,000 or more employees. 

At a minimum, it is best to conduct training annually to promote retention. For plants that work with gluten-free foods daily, an annual training session may be sufficient, but reinforcement training at random intervals may be necessary at facilities where working with gluten-free products is sporadic. However, this training does not need to be formal, classroom-based training. A simple standup team review of proper procedures, with time at the end for questions, can be a terrific way to reinforce learning. 

When designing training content, use visual aids and relevant examples whenever possible. For example, most people can relate to a can of beer because it forms a part of their daily lives, even if they do not drink it themselves. Remember, beer has barley malt, a gluten grain. To assess the effectiveness of training, incorporate quizzes and oral discussions, which are a good option when training employees where English is a second language or with staff that are uncomfortable taking tests.

Making Good on Gluten-Free Claims

Guiding principles underlying the Food Safety Modernization Act (FSMA)—hazard analysis risk-based preventive controls (HARPC) and hazard analysis and critical control points (HACCP)—are that cross-contact can happen at any time. Although risk is reduced in a facility dedicated to producing gluten-free or other allergen-free foods, it can never be eliminated altogether, so it is important to avoid a false sense of security. Oats can come into contact with gluten at any point in the supply chain, even if the facility practices stringent supplier protocols. GMP failures by staff may occur, as well. 

When shopping for products, gluten-free consumers rely on certification marks to identify products that are safe to eat. One safe way to fulfill responsibility as a manufacturer of gluten-free products is to obtain training materials from a credible source. Gluten-free organizations like the Gluten-Free Certification Organization (GFCO)3 and celiac centers like the Mayo Clinic are good places to start. Online resources are another excellent option. TEDEd offers an educational cartoon video, titled, "What's the Big Deal with Gluten?"4

The financial and reputational damage of a widely publicized recall can be a nightmare for any reputable food manufacturer. Implementing an effective training program that includes personal hygiene protocol, understanding the health issues associated with celiac disease and non-celiac gluten-sensitivity, and learning how to wear and decontaminate protective clothing can reduce or eliminate leading causes for food recalls.

With careful planning and a little imagination, a training program on GMPs for gluten-free manufacturing will go far in preventing an unwanted crisis while delivering products that gluten-free consumers love and trust.


  1. Kopolovich, Harry. M.D. "Food Recalls: Causes and Dangers." Hackensack Meridian Health. September 1, 2022.
  2. U.S. Food and Drug Administration (FDA). Retail Food Protection: Employee Health and Personal Hygiene Handbook. March 7, 2022.
  3. Gluten-Free Certification Organization (GFCO). "The Leader in Gluten-Free Certification." 2022.
  4. TEDEd and William D. Chey. "What's the Big Deal with Gluten?" YouTube. June 2, 2015.