Cross-Contact. What’s That About?
The proverb “Cleanliness is next to godliness” is often used to emphasise the importance of keeping our surroundings clean. Cleaning and sanitation are particularly important parts of an allergen management programme due to possible severe or lethal health consequences. This consequence makes it a high-risk consideration; one that must be managed along the food chain using a coordinated approach. Part of this approach is the allergen declaration by food business operators; however, a review of food recall information showed an increasing trend in products being recalled due to undeclared allergens. The US Food and Drug Administration’s (FDA) list of Recalls, Market Withdrawals and Safety Alerts has recall examples such as undeclared eggs, tree nuts, milk and soy. This goes to show that allergen declaration cannot be the sole strategy; it must be incorporated in a proactive approach.
A proactive approach means having an allergen management programme that speaks to how to prevent cross-contact and having a cleaning and sanitation programme that can prevent this. Cross-contact is when allergen is unintentionally transferred to foods that are without an allergen. Food business operators and workers are familiar with cross-contamination, which is the transfer of bacteria or other microorganisms to food; these are usually destroyed by heat or high pressure processing. However, these methods do not generally work on allergens.
Like cross-contamination, cross-contact can happen in three ways: People to food, food to food, and equipment to food. A food service worker, without adequate awareness of cross-contact, can unwittingly create a food safety hazard. It may be as simple as putting the peanut beside the orange or using the same spoon to portion out the rice that has been used for the eggs. Similarly to cross-contamination, cleaning is one of the most effective ways to prevent cross-contact. Since allergens can be hard to remove from food contact surfaces, it is important to note that “microbial-clean” does not mean “allergen-clean”. Factors that affect allergen cleaning include types of allergens and concentration in food, equipment (age, design, material of food contact surface), food processing temperature and type of cleaning method (wet or dry).
The method of cleaning is usually determined by the area or equipment designed to accommodate water. With wet cleaning, soaps and sanitisers are used along with automatic, semi-automatic or manual cleaning process. Commonly, the lines are flushed with ingredient; however, this material must be a part of the traceability system. In wet cleaning the acronym TACT is utilised. This stands for: Time (how long to apply), Action (automatic or manual), Chemical (component and concentration) and Temperature used. Chlorinated alkaline detergents and enzymes are excellent to remove protein soils, while acids and water effectiveness is poor. For dry cleaning, compressed air, vacuum and dry steam can be used or purging the lines with ingredients such as salt. Cleaning for “allergen-clean” can be very challenging in a dry environment.
Whatever method is used to achieve allergen-clean must be validated; that means ensuring the effectiveness of the allergen controls. Allergen cross-contact may not be prevented in all cases; however, strategies must be employed by the food business operator to reduce the levels. An allergen management programme is a must have.