Meat Hygiene refers to a set of specific standards and regulatory procedures that require the enforcement of rules and practices by relevant authorities to ensure the safety and efficiency of the meat consumed by consumers. To guarantee this, Hygiene and sanitation practices must be applied throughout the stages of production, processing, transportation, employee hygiene, equipment sanitation, and the provision of a suitable environment. Employees must sanitize the meat processing facility and equipment, ensuring the Hygiene of meat from disease-causing agents that can transmit serious health diseases, which is considered extremely important.
Principles of Meat Hygiene
There are three principles of Meat Hygiene that are essential and important for meat processing operations:
1- Prevention of microbial contamination during meat product manufacturing by following appropriate cleaning and sanitation practices.
2- Reducing microbial growth in meat products by storing them at low temperatures.
3- Reducing or eliminating the risk of microbial contamination by applying proper thermal processing and suitable packaging in the final processing stage.
Potential Source of Contamination
Failure to adhere to the specified conditions and required standards of Meat Hygiene by the relevant authorities can lead to contamination during various stages of meat production, including cutting, transportation, contamination of secondary products, and additives, resulting in a loss of quality and the contamination of the final meat products.
1- Good Hygienic Practices (GHP).
2- Hazard Analysis and Critical Control Points (HACCP) system.
Good Hygienic Practices in Meat Processing
To ensure that meat remains free from bacterial contamination or foodborne illnesses during slaughter and transportation, strict and serious adherence to meat Hygiene standards is essential. The health of the consumer should always be the top priority. Additionally, continuous refrigeration throughout the meat production and processing chain is crucial, along with the following interventions:
1- Wear clean protective clothing.
2- Wash hands before starting work and repeatedly during work.
3- Prohibit finger rings, watches, and bracelets.
4- Enter production areas in work attire only.
5- Clean/sanitize hands/tools/clothing if in contact with heavily contaminated individuals or parts of animals that may carry disease-causing agents.
6- Recent wounds resulting from knife cuts, etc., should be tightly covered with bandages. Workers with purulent wounds should not work with meat (risk of spreading Staphylococcus aureus bacteria).
7- Strict Hygiene in restrooms (removing aprons, hand washing, and hand sanitizing). Restrooms should remain clean and have no direct access to production areas (risk of Salmonella contamination).
8- Regular medical examinations for employees.
Hygiene During Meat Preparation:
1- Ideally, deboning and cutting should be performed in climate-controlled rooms (approximately +10°C) with low air humidity.
2- If there is visual contamination of meat during processing, do not attempt to wash it but remove it with knives by cutting away the superficial meat in the case of minor contamination. Discard meat in the case of severe contamination.
3- Do not wash the floor, walls, or equipment adjacent to meat processing operations or final products using a power hose (risk of airborne/droplet contamination).
4- Never reintroduce meat pieces that have touched the ground or other contaminated surfaces by mistake back onto worktables or meat processing machines.
5- Containers of meat, fat, semi-finished meat products, or finished products should not be placed directly on the ground but on sanitary and mobile platforms, etc.
Hygiene of Meat Processing Facilities (Design and Construction)
Meat processing facilities should adhere to basic hygiene standards to ensure and maintain clean and sanitary working conditions:
1- Provide changing rooms for shift employees.
2- Wall windows should be placed at a height of at least 2 meters above ground level to allow for thorough cleaning and sanitation of floors and walls. Window frames should be made of non-corrosive materials, such as aluminum or similar, and should not be coated.
3- Walls in all meat processing and product handling areas should have smooth, easily washable surfaces, with a minimum height of 2 meters in processing plants. It is preferable for walls to be covered with wall tiles or, at least, washable coatings.
4- Floors in the mentioned sections should be non-permeable to water and reasonably smooth for effective cleaning while also slip-resistant for worker safety.
5- To facilitate proper cleaning, the junction between the floor and walls should be rounded (not squared).
6- Meat processing rooms should have adequate ventilation.
7- Air conditioning is required only in cutting/deboning rooms (10-12°C). Electrical wiring systems, hot and cold water pipes, as well as compressed air should not obstruct cleaning operations and should be far from potential contamination sources. Insulation of hot water pipes should have smooth and washable surfaces.
8- Ventilation openings should be resistant to birds and insects.
1- Equipment should have appropriate sanitary design and construction. Designs should allow for easy and thorough cleaning and avoid any accumulation of organic materials that are difficult to remove. Food-grade construction materials should be used for surfaces and equipment that come into contact with food, and they should enable easy cleaning after processing operations.
2- Stainless steel should be used for all surfaces that come into contact with food, such as worktables, meat hooks (at least in contact with meat), knife blades, saws, cleavers, forks, and more.
3- Food-grade materials should be used for meat containers and other utensils.
Hazard Analysis and Critical Control Points (HACCP):
The Hazard Analysis and Critical Control Points (HACCP) system is a strict health monitoring scheme specific to the factory and the product. Its purpose is to prevent, detect, monitor, and/or reduce the risks that may occur inadvertently to consumer health to safe levels. Despite the existence of Good Hygienic Practices (GHP), potential risks cannot be ruled out, and they may occur at any stage of individual meat producers' processing. Specifically for meat processing factories, such risks may arise due to failure conditions such as batches of incoming raw meat with abnormal tissues or heavy contamination, cooling failures, failures in cooking/sterilization processes, abnormal acidity levels or faults in raw or finished products, errors in the application levels of curing salts and other additives, technical problems in sealing vacuum packages or cans with a risk of recontamination. Hazard Analysis and Critical Control Points (HACCP) systems act as additional warning systems for consumer protection to prevent such problems. In the event of potential hazards, they can be detected, contained, or removed at any stage.
Cleaning and Sanitation:
Cleaning, in general, refers to the removal of visible and physical/chemical dirt and, to some extent, bacteria from surfaces of equipment, and sometimes from the products themselves and the processing environment. In contrast, sanitization refers to disinfecting a product or product-contact surfaces by killing all disease-causing microorganisms to avoid any potential microbial contamination. Disabling the activity of microorganisms requires antimicrobial treatments, which are carried out in the food industry through hot water, steam, or the use of disinfectants.
The first step in cleaning floors and equipment is effectively removing physical debris, such as coarse solid particles, using a dry brush or broom and a shovel. This is typically referred to as "dry cleaning." Wet cleaning is done after the physical debris has been removed. Wet cleaning can be done manually or using high-pressure nozzles. However, this requires a sufficient amount of water.
Cleaning with equipment that produces a mixture of steam/pressurized water is more efficient, with impact temperatures reaching approximately 100 degrees Celsius. The drawback of this method is the formation of dense fog and airborne particles, which can not only spread unwanted microbes through water droplets (aerosols) but also affect facilities and equipment through high humidity and excessive condensation. For these reasons, the steam/water mixture is not suitable for meat processing facilities, and it is preferred to clean with cold or hot pressurized water.
A relatively new cleaning method for the food industry, especially large factories, is foam cleaning. Water foam containing detergents and other cleaning agents is sprayed on wet walls, floors, and equipment surfaces. The foam does not immediately disperse but adheres to surfaces, allowing for long-term cleaning. After sufficient contact time (at least 15 minutes), the foam is rinsed with water (using a hose or low-pressure water spray). Since high-pressure water spraying is not needed to rinse the foam, the spread of water droplets (aerosols) in the room being cleaned is reduced.
Traditional cleaning agents for manual use are usually alkaline substances, such as sodium carbonate (soda ash). These substances are effective at dissolving proteins and fats but can cause equipment and utensil corrosion if their pH is 11 or higher. Ideal cleaning agents should possess the following desired characteristics:
1- Wetting and penetration power to moisten, penetrate, and remove soil from equipment surfaces.
2- Emulsifying power.
3- Foaming power.
4- Dispersing power.
5- Insulating and emulsifying power.
6- Quick dissolution.
7- Non-corrosive to metal surfaces.
9- Stability during storage.
10- Should be easy on the hands.
11- Should have antimicrobial properties.
In the meat industry, different types of cleaning agents and disinfectants are used, each with one or more drawbacks. Commonly used cleaning agents and disinfectants in the meat industry include:
1- Alkaline Compounds:
- a) Sodium Hydroxide
- b) Sodium Carbonate
- c) Sodium Bicarbonate
- d) Sodium Silicate
- e) Sodium Phosphate: Digests, inactivates, or dissolves dirt, especially proteins, and acts as an emulsifier and germicide.
Generally used at a rate of 0.2 - 2% (NaOH).
- a) Nitric Acid
- b) Sulfuric Acid
- c) Hydrochloric Acid
- d) Phosphoric Acid
- e) Acetic Acid: Removes hard water deposits, which do not dissolve in alkaline substances. Generally used phosphoric acid (0.5%) HNO3 (2.0%). Strong acids can cause corrosion of surfaces and are also hazardous.
3- Complex Phosphates:
- a) Tetra Sodium Pyrophosphate
- b) Sodium Tripolyphosphate
- c) Tetra Sodium Diphosphate
- d) Hexametaphosphate: Softens water, displaces dirt by emulsification, prevents dirt particles from re-deposition.
4- Chelating Agents:
EDTA (Ethylenediaminetetraacetic Acid): Isolation, water softening, removal of metal deposits.
5- Wetting Agents:
Anionic (salts of various complex organic substances).
Non-ionic, e.g., Tyzor.
Common Disinfectants in the Meat Industry:
Disinfectants should be effective and fast-acting in killing microorganisms. In principle, the following groups of substances are generally used as disinfectants:
1- Compounds containing chlorine, e.g., sodium/calcium hypochlorite or chlorine gas. These have a corrosive effect on equipment.
2- Aldehydes (used in animal production, e.g., formaldehyde).
3- Phenols/cresols (used in medicine).
4- Alcoholic alkaline (pH 10 or higher) solutions, e.g., sodium hydroxide (used in animal production).
5- Acids (some organic acid substances used in food industries).
6- Quaternary Ammonium Compounds (used in food industries, as they are non-corrosive).
The optimal mixture of disinfectants used commercially includes:
- Organic acids
- Surface-active substances (surfactants)
- Peroxide compounds
Organic acids, apart from their disinfecting effect, reduce acidity because some disinfectants are more efficient at lower pH levels. Surfactants help penetrate organic matter, while peroxide compounds have a direct antimicrobial effect by denaturing proteins (viruses) and breaking down and penetrating cell walls, causing cell destruction (bacteria).
Cleaning and Sanitation Plans:
Specific cleaning and sanitization plans should be developed for designated processing areas. For example, meat grinders require precise and frequent cleaning and sanitation due to the high sensitivity of the resulting ground meat to health risks.