Allergens have been a growing concern for years in the food industry. As the number of allergens — and people affected by them — grows, so does concern about how food is protected as it’s being made.

“Today’s consumers have a heightened sensitivity to allergens, and we have a strong commitment to protect them,” said Bart Child, senior vice-president of commercial development of Nellson, Anaheim, Calif.

This heightened intolerance has revolutionized the food manufacturing industry to not only prioritize sanitation but also look at other ways to prevent cross-contamination. Companies that deal with many different allergens need stringent sanitation plans, strategic production schedules and, in some cases, isolated production lines.

Line isolation

“The benefits of line segregation allow us to produce products with multiple allergens on different lines at the same time,” Mr. Child said.

Line isolation can take on several forms, and it’s important for a bakery to find the system that works best for its customers, allergen matrix and production needs.

Levels of isolation

There are several types of line isolation to accommodate different plants’ needs, be they floorspace, allergen matrix, customer requirements or all three. A company can have dedicated bakeries free from a specific allergen. They can also have lines physically separated in the same building. Lines can exist in the same facility with minimal physical separation. In these cases, strict sanitation is a must.

“Ultimate isolation is achieved with totally separated facilities,” said Greg Carr, senior director of project planning, The Austin Co. “A plan to meet ultimate regulatory requirements could include selecting a big enough site to accommodate a separate plant in the future.”

When creating or expanding dedicated facilities, it isn’t just about shopping for a site with enough space, but it’s also about the neighborhood.

“Austin’s site location consultants will identify any nearby facilities that may use allergens that could conceivably contaminate new plant fresh air intakes,” Mr. Carr explained. “Where possible, Austin will request covenants that prevent future allergenic operations locating nearby.”

Ingredient segregation is a critical first step in keeping allergens away from other production areas.

Preventing cross-contamination within the same facility by separating lines requires more operational strategies as well as physical barriers to protect allergen-free production. While dedicated plants may be closest to a sure-thing in preventing cross-contamination, it’s not always feasible for every company.

“As a co-manufacturer that manages all types of allergens, building dedicated plants is not practical,” Mr. Child said.

Choose a level

Determining which level of isolation will work best for a bakery requires a consideration of several variables including the facility’s limitations, customer requirements, current allergen matrix and future production needs.

To choose the appropriate level of isolation, bakers must first identify what the risks for cross-contamination are and where opportunities for contamination exist in the process.

“We begin with a review of products and any allergens that are part of the recipes,” Mr. Carr said. “Next is predicting future products and allergens that may be used. With this information, Austin incorporates into the design what isolation is required and how it is to be achieved.”

Considering what allergens and level of business a bakery might want to attract in the future can guide bakers to what level of segregation they’d like to make room for in the event of future expansions.

If a bakery isn’t building a new facility, it’s important to evaluate the existing facility for changes to prevent any cross-contamination opportunities. For example, air locks are necessary to keep allergens from traveling across segregated production lines within a plant. However, existing mechanical systems must provide extra air to pressurize these locks. Bakers should also consider their budget and how much they are willing to spend.

“The most effective form of isolation is to create physical separation by assigning rooms to different allergens,” said Pablo Coronel, Ph.D., director of food processing and food safety at CRB. “However, this may be costly and requires planning long in advance.”

When working with an existing facility, the building itself may have limitations, specifically on space, that dictate how much isolation a bakery can achieve. Segregated warehouses, air locks, dedicated productions lines and their support systems all need space that some bakers just might not have without building a new facility.

Changeovers can signal to a baker when it’s time to make the leap from segregated lines to a dedicated allergen-free facility. When changeovers become cost-prohibitive, it’s time to make the change.

Line isolation

“Of course, that tipping point looks different for every company depending on its particular process and demands,” said Kevin Wilson, senior process engineer, Stellar. “If you’re experiencing a greater demand for your allergen-free products, it may be worth shifting those s.k.u.s to a dedicated plant to increase throughput and minimize downtime.”

Customers, whether they are end consumers or a brand, also have a big say in whether a bakery decides to use a dedicated facility or simply segregate the lines.

“A dedicated facility becomes necessary when products containing allergens are made at the same time as products that do not contain allergens, and the client wishes to avoid label disclosures such as ‘made in a facility which also processes tree nuts’ or when production is aimed at an allergy-sensitive population,” Dr. Coronel explained.

Hearthside Food Solutions, Downers Grove, Ill., has many facilities with varying degrees of allergen isolation, which enables the company to offer customers varying degrees of allergen control. All of this is discussed and vetted during the commercialization phase with input from the quality assurance, supply chain management, engineering and sales teams.

“Customers typically do a line approval audit prior to first production run,” said Dominic DeBlasio, vice-president of quality assurance and food safety, Hearthside Food Solutions. “Product label claims and certifications such as gluten-free are also discussed and reviewed. These decisions include not just the line but also the overall facility.”

Hearthside’s network of plants includes locations with isolated and dedicated allergen rooms, physical walls and separate air handling systems specific to each line, and separate facilities.

Isolated organization

In a facility dedicated to being peanut-free, gluten-free, tree-nut free or dairy-free, preventing cross-contamination is pretty straightforward. Nothing containing the offending allergen is allowed inside the facility, whether that’s ingredient deliveries, employee lunches or vending machine contents. This high level of security combined with stringent sanitation programs minimizes the risk of an allergen sneaking onto the production floor.

A bakery with shared production lines, no matter how segregated, requires specific design strategies and operational practices to ensure no cross-contamination occurs.

“If isolation is to be achieved in a single building, several issues need to be addressed, including cross-contamination at the receiving docks or silos, separate and isolated storage areas, misuse of tools and equipment, air movement and employee movement,” Mr. Carr said. “It’s always easier and less costly to include isolation systems when the plant is first constructed. The cost and disruption to make modifications later can be mitigated if those future changes are planned in the initial design.”

Ingredient segregation is a critical first step in keeping allergens away from other production areas. Ingredient receiving is a soft spot where allergens can come into contact with ingredients for non-allergen product. It’s important that these are received on separate docks and then stored away from the others. Warehouses can be segregated by racks. Dr. Coronel suggested that half-used containers be secured with double closures to prevent powders and particulates from accidentally mixing with other products.

“Shipping and receiving should be aware of allergens, and extra care must be taken to prevent damage to allergen bags and cross-contamination,” he said.

Not only does ingredient storage need to be segregated, but separate ingredient delivery systems can minimize the risk of cross-contamination, said Mr. Wilson. Pump/tank systems, scaling hoppers and conveying lines that only handle ingredients for allergen products reduce the amount of downtime necessary for sanitation. Mapping out and controlling a flow path for allergens moving through the facility can also minimize opportunities for contamination.

“Today’s consumers have a heightened sensitivity to allergens, and we have a strong commitment to protect them.”

Bart Child, Nellson

Nellson saw the need for this after receiving feedback from its various teams on how the company could improve allergen protection.

“This resulted in our commitment that every one of our factories not only had segregated lines but also our materials handling, storage, processes and protocol needed to be modified,” Mr. Child explained.

The bar manufacturer’s new facility in Ontario, Calif., was built with five segregated production lines, each functioning independently. Every one has its own electrical system, sanitation and production rooms and other support systems. This allows each line to operate as a plant-within-a-plant.

Dust and air movement is another risk factor that must be mitigated to keep allergens separate across production lines. Bakers want to minimize dust and filter the air to keep allergens from traveling throughout the plant.

“Dust collection helps reduce the migration of airborne particulates that are generated from the process,” said Brian Gifford, mechanical engineer at CRB.

Air locks can also ensure allergen particulates stay in their dedicated areas. Placed at entries into dedicated allergen spaces, air locks can be maintained at a higher pressure than surrounding spaces. This creates a bubble or hill that pushes clean filtered air into the allergen space and the area connected to the air lock and prevents contaminated air from flowing into an allergen-free space.

“Air locks are always a good option to create full segregation between an allergen room and surrounding areas because they protect the room from equalizing in pressure with the adjacent space when a door is opened,” Mr. Gifford said. “This could allow particulates to migrate out of the room as people exit or enter a room.”

Mr. Gifford stressed that when using an air lock, there must be adequate space in the facility to accommodate a separate room, and the HVAC system must also be retrofitted and rebalanced to accommodate it.

Accounting for people

A well-designed facility can minimize risks of cross-contamination, but bakeries still must account for an unpredictable factor: the people moving throughout a plant. Their clothes and shoes can carry allergen particulates across airlocked thresholds. They can also move pieces of equipment from an allergen area to an allergen-free area. Without the proper tools and training, employees can undo the safety valves put in place to prevent contamination.

Line isolation

“Employee awareness and training is key to our allergen control program,” Mr. DeBlasio said. “We are a process-driven environment dedicated to best practices. Constant vigilance and communication are critically important.”

Hearthside provides employees on the production floor with One Point Lessons on key steps for quick visual reminders throughout the manufacturing process.

Mr. Child said Nellson also is committed to ongoing training. The company has a robust program to ensure that workers honor the integrity of the segregated lines.

When managing employee movement, hand and boot washing are standard procedures before entering or leaving an allergen room. This prevents particles from the floors or leftover on hands from being tracked into allergen-free areas.

Allergens and the concerns around them aren’t going away any time soon. As providers of safe food, it’s important for bakers to have the safest manufacturing environment possible, whether that’s segregated lines under one roof or a dedicated allergen-free facility.