7. ESTABLISHMENTS FOR SEAFOOD PROCESSING

In this chapter some requirements for establishments for (sea) food processing will be discussed. A number of books (Shapton and Shapton 1991, Hayes 1985, ICMSF 1988) and official regulations (e.g. EEC 1991b) give detailed information on requirements for buildings, equipment and processing procedures and these should be consulted if new establishments are being constructed. Some of the more important aspects are considered below.

7.1. PLANT LOCATION, PHYSICAL ENVIRONMENT AND INFRASTRUCTURE

Early considerations in building a new plant is the identification of a suitable location. A number of factors should be considered such as physical, geographical and infrastructure available.

A plant must be located on a plot of adequate size (for present needs and future developments), with easy access by road, rail or water. An adequate supply of potable water and energy must be available throughout the year at a reasonable cost. Special considerations must be given to waste disposal. Seafood processing plants usually contain significant amounts of organic matter which must be removed before waste water is discharged into rivers or the sea. Also solid waste handling needs careful planning, and suitable space, away from the plant, must be allocated or be available.

Assessment of pollution risk from adjacent areas must also be considered. Contaminants such as smoke, dust, ash, foul odours (e.g. neighbouring fish meal plant using poor raw material) are obvious, but even bacteria may have to be considered as airborne contaminants (e.g. proximity of a poultry rearing plant upwind may be a source of Salmonella sp).

The immediate physical surroundings of a seafood factory should be landscaped and present on attractive view to the visitor (-or potential buyer of products). However, this should be done in a way so rodents and birds are not attracted. Shrubbery should be at least 10 m away from buildings and a grassfree strip covered with a layer of gravel should follow the outer wall of buildings. This allows for thorough inspection of walls and control of rodents.

7.2. BUILDINGS, CONSTRUCTION AND LAYOUT

A food processing plant shall provide (quoted from Troller 1983):

• Adequate space for equipment, installations and storage of materials.

• Separation of operations that might contaminate food.

• Adequate lightning and ventilation.

• Protection against pests.

The requirements of external walls inclusive roofs, doors and windows are that they should be water-, insect- and rodent proof. Internal walls, on the other hand, should be smooth, flat, resistant to wear and corrosion, impervious, easily cleanable and white or light coloured. Also the floors should ideally be impervious to spillage of product, water and disinfectants, durable to impact, resistant to disinfectants and chemicals used, slip resistant, non-toxic, non-tainting and of good appearance and easy repairable. Floors should be provided with slope to drains to prevent formation of puddles. The technical requirements, choice of materials, cost etc. to obtain these goals may be found in a number of publication such as Shapton and Shapton (1991), Imholte (1984), Troller (1983).

The general layout and arrangements of rooms within a processing establishment is important in order to minimize the risk of contamination of the final product. A large number of bacteria (pathogens and spoilage bacteria) enter with the raw material. To avoid cross contamination, it is therefore essential that raw material is received in a separate area and stored in a separate chillroom. From here the sequence of processing operations should be as direct as possible - and a “straight line” process flow is regarded as the most efficient (Hayes 1985). This layout minimizes the risk of recontamination of a semi-processed product.

Figure 7.1. Clean, orderly and possibly landscaped outside appearance of a food plant is the first impression to a visitor.

A clear physical (e.g. a wall) segregation between “clean” and “unclean” areas is of prime importance. “Unclean” areas are those where raw material is handled and often a cleaning operation (wash) or e.g. a heat treatment (cooking of shrimp) is marking the point, where the process flow goes from “unclean” to “clean” areas. Thus a “clean” area is defined by ICMSF (1988) as an area where any contaminant added to the product will carry over to the final product, i.e. there is no subsequent processing step that will reduce or destroy contaminating microbes. Other terminologies used for “clean” areas are “High Care Areas”.

Also cooled rooms must be separated from hot rooms where cooking, smoking, retorting etc. are taking place. Dry rooms must be separated from wet rooms and ventilation must be sufficient to remove excess humidity.

The separation between the clean and unclean areas must be complete. There should be no human traffic between these areas, and equipment and utensils used in the unclean areas should never be used in the clean area. This means that there should also be separate wash and hygiene facilities for equipment and personnel in these areas. For easy identification the personnel should wear different coloured protective clothing for different operations (e.g. white in the clean area and blue in the unclean).

Equally important in layout and design of food factories is to ensure that there are no interruptions and no “dead ends” in the product flow, where semiprocessed material can accumulate and remain for a long time at ambient temperature. Time/temperature conditions for products during processing are extremely important critical control points (CCPs) in order to prevent bacterial growth. This means that a steady and uninterrupted flow of all products is necessary in order to have full control of this critical factor. If any delays in product flow are necessary, the products should be kept chilled.

In addition to facilitate product flow, the factory layout and practices should ensure that:

• All functions should proceed with a no of criss-crossing and backtracking.

• Visitors should move from clean to unclean areas.

• Ingredients should move from “dirty” to “clean” areas as they become incorporated into food products.

• Conditioned (e.g.chilled) air and drainage should flow from “clean” to “dirty” areas.

• The flow of discarded outer packing material should not cross the flow of either: unwrapped ingredients or finished product.

• There is sufficient space for plant operations including processing, cleaning and maintenance. Space is also required for movement of materials and pedestrians

• Operations are separated as necessary. There are clear advantages in minimizing the number of interior walls since this simplifies the movement of materials and employees, makes supervision easier, and reduces the area of wall that needs cleaning and maintenance (the list is partly after Shapton and Shapton 1991).

Some of the principal requirements for an ideal establishment are outlined in Figure 7.2.

Figure 7.2.Simplified factory layout

7.3. UTENSILS AND EQUIPMENT

A great variety of utensils and equipment is used in the fish industry. There is an abundance of advice and regulations available concerning the requirements for equipment. All of them agree that the food equipment should be non-contaminating and easy to clean. However, the degree of stringency in hygienic requirements must be related to the product being processed. Raw fish for example, do not require the same standard of hygiene as cooked and peeled shrimp. Criteria for hygienic design are particularly important for equipment used in the later stages of processing and particularly after a bacteria-eliminating processing step.

There are seven basic principles for hygienic design agreed upon by a working party appointed by Food Manufacturers Federation (FMF) and Food Machinery Association FMA (FMF/FMA 1967) as quoted by Hayes (1985):

1. All surfaces in contact with food must be inert to the food under the conditions of use and must not migrate to or be absorbed by the food.

2. All surfaces in contact with food must be smooth and non-porous so that tiny particles of food, bacteria, or insect eggs are not caught in microscopic surface crevices and become difficult to dislodge, thus becoming a potential source of contamination.

3. All surfaces in contact with the food must be visible for inspection or the equipment must be readily disassembled for inspection, or it must be demonstrated that routine cleaning procedures eliminate possibility of contamination from bacteria or insects.

4. All surfaces in contact with food must be readily accessible for manual cleaning, or if not readily accessible, then readily disassembled for manual cleaning, or if clean-in-place techniques are used, it must be demonstrated that the results achieved without disassembly are the equivalent of those obtained with disassembly and manual cleaning.

5. All interior surfaces in contact with food must be so arranged that the equipment is self emptying or self draining.

6. Equipment must be so designed as to protect the contents from external contamination.

7. The exterior or non-product contact surfaces should be arranged to prevent harbouring of soils, bacteria or pests in and on the equipment itself as well as in its contact with other equipment, floors, walls or hanging supports.

In the design and construction of equipment it is important to avoid dead areas where food can be trapped and bacterial growth take place. Also dead ends (e.g. thermometer pockets, unused pipe work T-pieces) must be avoided, and any piece of equipment must be designed so the product flow is always following the “first in first out” principle.

Cleanability of equipment involves a number of factors such as construction materials, accessibility and design. The most common design faults which cause poor cleanability are (Shapton and Shapton 1991):

• Poor accessibility (- equipment should be placed at least 1 m from wall, ceiling or nearest equipment).

• Inadequately rounded corners (minimum radius should be 1 cm, but 2 cm is regarded as optimum by the American 3-A Sanitary Standards Committee (Hayes 1985).

• Sharp angles.

• Dead ends (including poorly designed seals).

One general problem of food processing involves the extremes of temperature, abundant use of water, condensation and contamination of food from overhead pipes and surfaces. Equipment design must consider this and include proper protection.

Equipment design is one of the major problems in modern food hygiene. A great number of new machines and equipment are designed and constructed without proper attention to the fact that these tools have to be cleaned and sanitized. The EEC Directive 89/392/EEC (EEC 1989) addresses machinery safety and hygiene regulations. Some of the highlights are:

• Machinery containing materials intended to come in contact with food must be designed and constructed so these materials can be cleaned before each use.

• All surfaces and their joinings must be smooth, with no ridges or crevices that could harbor organic materials.

• Assemblies must be designed to minimize projections, edges and recesses. They should be constructed by welding or continuous bonding, with screws, screwheads and rivets used only where technically unavoidable.

• Contact surfaces must able to be readily cleaned and disinfected, and built with easily dismantled parts. Inside surfaces must be curved in a way to allow through cleaning.

• Liquid derived from foods, as well as cleaning, disinfecting and rinsing fluids should be able to be readily discharged from machinery.

• Machinery must be designed and constructed to prevent liquids or living creatures - primarily insects - from entering and accumulating in areas that cannot be cleaned.

• Machinery must be designed and constructed so that ancillary substances, such as lubricants, do not come in contact with food.

The directive also sets out a certification system where machinery is checked for compliance and tagged with an EC mark if found to be satisfactory. Certification is not retrospective and manufacturers have two years to bring new machinary into compliance.

Apart from literature already cited, additional useful material and information on hygienic design are found in Anon. (1982, 1983), Milledge (1981) and Katsuyama and Strachan (1980).

7.4 PROCESSING PROCEDURES

Processing procedures are Critical Control Points (CCP-2) in the processing of all food products. All processing techniques and procedures therefore must be designed and aimed at management of contamination and/or growth of microorganisms in food. Such procedures are termed “Good Manufacturing Practices” (GMP).

Detailed codes for GMP must be elaborated for each factory and each processing line (like the HACCP-concept). However a number of details to be included in the GMP-codes have been elaborated by regulatory agencies and international organizations. The most comprehensive example is the work undertaken by the “Codex Alimentarius Commission” of the United Nations, who has published a series of Recommended Codes of Practices (Codex Alimentarius 1969-) including general principles of food hygiene (Vol. A) and a number of fish products(Vol. B) including codes for fresh fish, canned fish, frozen fish, shrimp, molluscan shellfish, lobsters, crabs, smoked fish, salted fish and minced fish. These codes are continuously updated and should be consulted for detailed information on recommended processing procedures.

7.5. PERSONAL HYGIENE

Personal hygiene is a CCP-2 in preventing microbial contamination or any foreign body contamination of fish products. A list of 15 basic points related to personal hygiene has been drawn up by Thorpe (1992) and are shown below:

Personal hygiene requirements for personnel working in production areas and materials warehouses

1. Protective clothing, footwear and headgear issued by the company must be worn and must be changed regularly. When considered appropriate by management, a fine hairnet must be worn in addition to the protective headgear provided. Hair clips and grips should not be worn. Visitors and contractors must comply with this regulation.

2. Protective clothing must not be worn off the site and must be kept in good condition. If it is in poor condition, inform your supervisor immediately.

3. Beards must be kept short and trimmed and a protective cover worn when considered appropriate by management.

4. Nail varnish, false nails and make up must not be worn in production areas.

5. False eyelashes, wrist watches and jewellery (except wedding rings, or the national equivalent, and sleeper earrings) must not be worn.

6. Hands must be washed regularly and kept clean at all times.

7. Personal items must not be taken into production areas unless carried in inside overall pockets (handbags, shopping bags must be left in the locker provided).

8. Food and drink must not be taken into or consumed in areas other than the tea bars and the staff restaurant.

9. Sweets and chewing gum must not be consumed in production areas.

10. Smoking or taking snuff is forbidden in food production, warehouse and distribution areas where ‘No Smoking’ notices are displayed.

11. Spitting is forbidden in all areas on the site.

12. Superficial injuries(e.g. cuts, grazes, boils, sores and skin infections) must be reported to the medical department or the first aider on duty via your supervisor and clearance obtained before entering production areas.

13. Dressings must be waterproof and contain a metal strip as approved by the medical department

14. Infectious diseases (including stomach disorders, diarrhoea, skin conditions and discharge from eyes, nose or ears) must be reported to the medical department or first aider on duty via your supervisor. This also applies to staff returning from foreign travel where there has been a risk of infection.

15. All staff must report to medical department when returning from both certified and uncertified sickness.

7.6. APPLICATION OF THE HACCP-PRINCIPLE IN ASSESSMENT OF ESTABLISHMENTS

A great variability exists in the size and extent of handling in fish processing establishments. Accordingly the hygienic requirements and the design in fish handling areas may vary considerably. Quite obviously the requirements to a small establishment which is only repacking fish in ice and catering for a local market are different from the hygienic requirements to a large establishment, processing a variety of sophisticated products including heat treated and composite products and exporting to countries all over the world, However, all the requirements commonly listed in legislation and codes of practice are not equally important. The more important factors include: facilities for water supply, waste disposal and cooling and cold storage facilities and -capacity. Of less importance are buildings, ventilation, factory location, clothes changing facilities, lightning and roadways (ICMSF 1988).

The forms shown in Figure 7.3 have been utilized in assessing fish factories using the HACCP-principle. Only the most important factors are evaluated and given a rating from A to C, where A and B are expressions of degrees of excellence and niceties, while a rating of C is given to a condition which is unacceptable and needs immediate correction before further operations can take place. Thus it is an attempt to “distinguish between the nice and the necessary” which is the same approach as applied in the HACCP-principle.

ASSESSMENT OF FISH FACTORY

A) Excellent, good or only minor deficiency
B) Less good, serious deficiencies
c) An unacceptable situation, which may result in an unwholesome product representing health of safety threats.

Figure 7.3 Example of simplified form used in assessing fish factories.