Is the use of enzymatic detergents in the food industry an alternative?
Innovation and the development of new hygiene products for the food industry provide new solutions for cleaning and disinfection, thus improving the safety, efficiency and sustainability of these processes. Innovation in the field of detergency and disinfection explores the applicability and performance of new technologies such as enzymes, proteins that act as biocatalysts (accelerate chemical reactions such as the hydrolysis of biomolecules). Due to the great diversity of enzymes available at industrial level and the specificity of the reactions they catalyse, the use of enzymes has become widespread in many fields, including food production (e.g. milk coagulation, cheese flavour and texture enhancers, dough consistency reduction and juice clarification), biotechnology, wastewater bioremediation, biofuel production, detergency and even in the field of cosmetics (1).
In the field of detergency, the most interesting characteristics of enzymes are their specific activity at moderate pH values and their biodegradability. Moreover, they are obtained from fermentations carried out by microorganisms in culture, which allows them to be generated on a sufficiently large scale for industrial use (2). With these characteristics, adding enzymes to detergent formulations is possible and feasible, as low quantities of enzymes are required to obtain the desired effect. Thus, enzymatic detergents can act specifically on dirt or other substrates by breaking them into smaller particles and increasing the effectiveness of the detergent.
The laundry sector has more than 30 years of experience in the use of enzymatic detergents (3), with favourable results in terms of efficiency, dirt removal and also in the sustainability of the process. In this field, it has been observed that the use of enzymes has made it possible to reduce the time and temperature of washing, resulting in energy and water savings (4). In the food industry, the scenario is different. Although enzymatic detergents represent a green and highly efficient alternative to conventional detergents, their use for general cleaning is limited and enzymatic detergents find their market niche in specific applications, such as biofilm or allergen control and membrane cleaning.
Biofilm control treatment
One of the most important applications of enzymatic detergents in the food industry is the control of biofilms, due to the microbiological risk they pose to the food industry. To understand the role of these products in the treatment of biofilms, it is first necessary to know what they are.
Reversible adhesion → Irreversible adhesion → The proliferation and production of the expolymer → Maturing → Dispersion
Biofilms are microbial structures that form on surfaces when microorganisms stick to them and begin to group, divide and secrete extracellular polymeric substances (EPS). These substances allow the microorganisms to stick to each other and to the surface and also create a protective layer against external physical and chemical agents. Biofilms, due to this EPS layer, are structures that are very difficult to remove with conventional detergents and disinfectants. Moreover, they can harbour multiple pathogenic microorganisms such as Listeria monocytogenes, Salmonella or Campylobacter, among others. Therefore, their presence poses a significant risk to the food industry.
Biofilms find ideal environments for their formation at points in the production chains of food industries; the formation of biofilms requires the presence of nutrients, moisture and surfaces to adhere to. Therefore, the control of biofilms is becoming increasingly important in the hygiene plans of food industries. Due to the difficulty to attack biofilms and their resistance to conventional products, specific cleaning and disinfection products and protocols have been developed to achieve their controlling using, among others, enzymatic technology. In this case, enzymatic detergents present a combination of enzymes that break down the EPS matrix of biofilms, acting on proteins, lipids and sugars, the main components of EPS. Breaking down the EPS matrix means removing the protective layer of the biofilms and exposing the microorganisms inside them to the outside environment, so that if a disinfectant is applied, it will be able to reach the microorganisms that formed the biofilm, act on them, and eliminate them (5).
Enzymatic detergents used in the food industry are neutral detergents, do not damage surfaces and are safer for operators. They are also biodegradable and leave no residues. They are generally applied at temperatures between 45-55°C and using the same foaming equipment or CIP systems as conventional detergents. Product application temperature is key for enzymatic detergents. Because enzymes are proteins, if the enzymatic detergent is applied at temperatures above 55°C, the enzymes may degrade and cease to function. Conversely, if applied at lower temperatures, the performance of the product will not be as expected.
There are different products and protocols for biofilm controlling depending on the treatment required. There are shock protocols and preventive protocols. The former are applied when biofilm problems have been detected and rapid removal of biofilms is required. The latter is applied to prevent the formation of new biofilms or the reappearance of biofilms. These protocols differ in the products that are used or the concentrations that are applied and in the frequency of application of the product, with shock treatments being more concentrated in time and preventive treatments being applied on a regular basis at a specific frequency that can range from weekly to monthly, depending on the type of industry.
Allergen Elimination
Another application of enzymatics in the food industry is for the removal of allergens. Allergens are proteins from different foods that cause a response from the immune system of consumers who are allergic to them: food allergies.
Crustaceans, eggs, fish, peanuts, soya, dairy, nuts, celery, mustard, sesame seeds, sulphur dioxide and sulphites, molluscs, lupins, gluten, etc.
Currently, the presence of allergens in food and their declaration is regulated by the EU (Regulation (EU) 1169/2011). Annex II of this regulation describes the 14 most important allergens in food (6). Among these allergens, gluten, dairy, egg, crustaceans, soya, nuts and peanuts are some of the allergens to which the majority of the population is allergic. Traces of these substances in a product can trigger an immunological reaction in the affected person. This adverse reaction can cause very serious health symptoms and situations. It is for this reason that the presence of undeclared allergens on food labels should be zero. It would be most appropriate to be able to guarantee the absence of these allergens in the products produced, which can be achieved by having specific production lines and avoiding cross-contamination.
Proper hygiene, especially including specific protocols for allergen removal, is of vital importance to prevent cross-contamination of food, especially in cases where it is not possible to separate production lines. These specific protocols require the use of allergen products. This turns out not to be an easy task. In these cases, again, enzymes can contribute a lot. Allergens are proteins and can therefore be broken down by the action of enzymes, helping to increase the allergen removal efficiency of detergents. It is always necessary to verify the absence of allergens in the protection area when changing products. If the absence of allergens cannot be guaranteed, the possible presence of the allergen must be correctly indicated on the label (precautionary labelling) according to EU regulations (regulation (EU) 1169/2011), in order to achieve a high level of consumer health protection and to provide maximum information to consumers.
In the food industry, the use of enzymatic detergents increases the safety of the finished product, helping to avoid the presence of biofilms and allergens, in an effective and more environmentally friendly way.
Membrane cleaning
Another major use of enzymatics is in the hygiene of membranes used in certain food industries. Today, membrane separation processes are common in the dairy industry due to their numerous advantages; their simplicity, high selectivity, mild operating conditions, ease of scale-up and reduced energy consumption compared to conventional methods.
Membranes are semi-permeable and selective barriers to the passage of various substances that must be periodically conditioned to remove dirt from both their surface and the interior of their porous structure in order to recover their properties. For example, UF membrane cleaning processes are a key step in the overall production process in the food industry. Typically, cleaning protocols need to be carried out on a daily basis, hence the importance of designing good cleaning protocols depending on the type of fouling (surface or internal in the porosity structure) and the composition of the food itself. Both lead to a decrease in the amount of permeate flux in the membranes, which results in a decrease in the overall production and lifetime of the membranes, as well as an increase in operating costs and energy consumption.
The use of enzymatic products in membrane cleaning tasks is an appropriate and less aggressive option compared to other types of products, due to their own natural characteristics; they do not require high temperatures, as well as milder pH levels. In this way, we can point out that the use of enzymatic products means lower energy consumption (due to the operation at mild temperatures) and a minimum environmental impact (as they are biodegradable compounds), as well as extending the useful life of the membranes.
Efficiency, green alternatives and affordability are the characteristics that the food industry is looking for in its cleaning protocols. Enzymatic products fit perfectly into this premise, becoming an alternative to other chemical products. In addition to controlling biofilms and allergens, as well as cleaning membranes, this type of product is also suitable for general cleaning tasks in the food industry, removing dirt from different types of surfaces in production plants.
Bibliography
Chapman, J., Ismail, A. E. & Dinu, C. Z. (2018) Industrial Applications of enzymes: recent advances, techniques and outlooks. Catalyst 8 (238)
Kirk, O., Vedel Borchert, T. & Crone Fuglsang, C. (2002), Industrial enzyme applications. Current Opinion in Biothechnology 13: 345-351.
Kumar, D., Savitri, N., Thakur, N., Verma, R & Bhalla T.C. (2008) Microbial proteases and apllication oas Laundry detergent additive. Research Journal of Microbiology 3 (12): 661-672.
Olsen, H. S. & Falholt, P. (1998) The role of enzymes in modern detergency. Journal of Surfactants and Detergents 1: 555-567.
Delhalle, L., Taminiau, B., Fastrez, S., Fall, A., et al., (2020). Evaluation of enzymatic cleaning on food processing installations and food products bacterial microflora. Frontiers in Microbiology. Doi: 0.3389/fmicb.2020.01827.
Corbatón Báguena, María José (2015). Cleaning of ultrafiltration membranes applied in the food industry by means of non-conventional techniques and characterisation of membrane fouling. Doctoral thesis UPV.
Regulation (EU) 11669/2011 of the European Parliament and of the Council (25 October 2011)
Authors
Mercè Berga
Degree in Biology from the University of Girona. PhD in marine biology and limnology from the University of Uppsala (Sweden) with the thesis “Assembly mechanism in aquatic bacterial communities – The role of disturbances, dispersal and history”. R&D Microbiologist at CHRISTEYNS Spain.
Joan Estornell
Marketing Manager Food Hygiene at CHRISTEYNS. Bachelor of Information Sciences. Master in Advertising Account Management. Strategic Innovation in Marketing and Advertising (UAB). Master in Digital Business. Digital Marketing (ESIC Business & Marketing School). Hygienist Course in the Food Industry (Betelgeux).
