The Specialist Cheesemakers Association - Best Code of Practice

5.1 The SCA promotes the use of traditional techniques and traditional methods of cheese manufacture, where cheese is made on the farm using milk originating from that farm. The SCA also promotes the safe use of unpasteurised milk in cheese production. This is because it provides an opportunity to make cheese of the very best quality. There is no loss of unique flavours from the pastures, and no denaturing of the milk protein by heat. This redoubles the need for attention to the hygienic quality of the basic raw material, because the salting, drying, and the increase in acidity are the only steps in the operation where any harmful micro-organisms present in the cheese may be eliminated or reduced to safe levels.

5.2 If you are in any doubt about the microbiological quality of the milk you should not use it. Seek advice from your Food Authority or the SCA. A regular programme of microbiological testing will assist you. Pasteurising milk will reduce pathogenic micro-organisms to safe levels.

CHIEF MEDICAL OFFICER'S ADVICE

5.3 The Government's Chief Medical Officer has issued specific advice that some patients and pregnant women should avoid eating certain soft cheeses. The method of manufacture, storage conditions, and the time the cheese may be kept before eating can allow harmful organisms to multiply. The advice applies to both unpasteurised and pasteurised soft cheeses. This places further emphasis on the need to observe best hygienic practices at all stages.

BASIC REQUIREMENTS FOR CHEESEMAKING PREMISES

5.4 The basic requirements for a cheesemaker are that premises should:

be clean, tidy, free of rubbish, and be maintained in good repair;
be designed and constructed to permit good hygienic practices;
have an adequate supply of hot and cold potable (drinking) water;
have suitable controls in place to protect against pests: no animals or birds, etc., should be allowed in cheesemaking or handling areas;
have adequate natural and/or artificial lighting;
have sufficient natural and/or mechanical ventilation;
have clean lavatories which do not lead directly into food rooms;
have adequate hand washing facilities with soap, and suitable hand drying facilities, e.g., disposable towels;
have adequate storage for ingredients, finished products, cleaning materials, etc.;
have adequate facilities for washing of equipment, food contact surfaces, etc.;
have adequate drainage.

STRUCTURE OF PREMISES

5.5 A purpose built facility is of course ideal, but it is not essential. Many specialist cheesemakers operate from units within traditional farm buildings. Your local Food Authority can advise on whether existing buildings can be adapted to meet the structural requirements laid down in the Regulations, and on design and layout of premises.

5.6 Provided walls, floors, ceilings and other non food contact surfaces are maintained in good and clean condition, they may be of brick, stone, metal, wood or any other acceptable material.

5.7 Surfaces which come into contact with cheese, e.g., shelves, need to be made of a material which will not harbour harmful organisms. Examples are marble, stainless steel, or food grade plastic. However, it should be remembered that solid, impermeable surfaces which do not allow drainage may encourage moisture build up between the cheese and the surface. This may in turn cause damp patches in the cheese or encourage the growth of harmful micro-organisms.

5.8 For these reasons, close grained wood is often a suitable surface, as are plastic strip mats or other means of allowing a certain amount of air circulation between the cheese and the surface. You will need a derogation if you wish to use wooden shelves in direct contact with cheese. See Milk and cheesemaking: The Law for details of the range of derogations available. Remember that all surfaces which come into contact with the cheese must be cleaned and disinfected regularly.

5.9 Constituents in many materials can migrate into cheese, sometimes at unacceptable levels which could cause a health hazard or taint. materials and articles that come into contact with cheese should meet the requirements of the food contact materials and articles legislation. If you are in doubt about the suitability of a particular material, contact your Food Authority for advice.

5.10 You may find it necessary for the purpose of air flows and humidity controls in, for example, a maturing room, to have openable windows. This is acceptable, but you will find it necessary to cover openable windows with screens to protect against pests.

MILK RECEPTION

5.11 Milk for the manufacture of cheese should be of a very good hygienic quality. See Annex C for legal standards for milk, plus SCA recommendations of what standards to aim for. On delivery of the milk, you should be aware that:

harmful bacteria may be present in the milk;
antibiotic residues may be present in the milk.

5.12 You can control these hazards by:

purchasing from a known supplier who exercises good herd management, especially mastitis control, and has a herd clinically free from any other disease problems such as salmonellosis etc., and has a clear cut strategy for dealing with diseased animals, when disease arises. You may find it useful to visit your supplier and examine their microbiological test results. You could also check with them that they are registered with the Dairy Hygiene Inspectorate in England and Wales, or licensed with the Food Authority in Scotland;
ensuring that milk bought in is only accepted if the temperature on arrival is 6^oC or less;
checking milk on receipt for any obvious visual problems, e.g., blood or clots;
if the milk is from your own herd, ensuring that it has been stored at a temperature of 6^oC or less;
wherever possible, only accepting milk within 24 hours of milking;
ensuring that raw milk has a low total bacterial count (TBC). The Regulations require a TBC of less than 100,000 per ml, but the SCA recommend less than 10,000 per ml for raw milk to ensure the milk is of good hygienic quality;
ensuring that milk, whether bought in or from your own herd, is free from antibiotic residues. Any milk containing antibiotic residues should not be used for cheesemaking, because it will inhibit the growth of the cheese starter bacteria. Then the acidity will not develop in the normal way and the curds will remain soft and floppy. Simple and cost effective tests are now available for antibiotic screening on the farm.

STORAGE OF MILK

5.13 You should be aware that:

harmful bacteria can grow and multiply if milk is stored at the wrong temperature and for too long a time;
dirty equipment will contaminate the milk.

5.14 You can control these hazards by:

storing milk at less than 6^oC;
using milk within 36 hours of milking;
ensuring that milk storage equipment has been cleaned, and is disinfected prior to use;
if milk is bought in, ensuring that the above conditions are met.

HEAT TREATMENT

5.15 If milk is to be pasteurised before cheesemaking then adequate heat treatment must be carried out. Survival or growth of food poisoning bacteria, or bacteria which may spoil the cheese, are hazards which are likely to occur if:

you fail to achieve the correct temperature or correct holding time;
pasteurised milk becomes mixed with raw or inadequately heat treated milk.

5.16 You can control these hazards by:

ensuring thermometers on the pasteurising plant are calibrated to ensure the correct minimum temperatures. A temperature of 72^oC for 15 seconds for HTST pasteurisers (or an equivalent combination, e.g., 63^oC for 30 minutes for batch pasteurisers) is necessary;
ensuring the flow diversion device within the pasteuriser will reject milk not heated to the required temperature for the required time, and redirect it to go through the pasteuriser again;
checking daily that the flow diversion valve on continuous flow pasteurising plants is operating correctly;
ensuring that the heating plates of HTST pasteurisers do not leak by regularly monitoring the results of phosphatase testing of pasteurised milk;
ensuring equipment is adequately maintained, correctly calibrated, and serviced regularly.

THERMISATION

5.17 Thermisation is a process of treating milk by heating to a temperature of between 57^oC and 68^oC for at least 15 seconds. Thermisation does not ensure that all pathogens are killed and therefore is not recommended.

STARTERS

5.18 Freeze dried starters are suitable for small operations. Packets should be stored frozen at minus 18^oC. Manufacturers do not recommend sub-division of packets. These may be stored for a few days at below 6^oC, prior to use, even if they are normally frozen.

5.19 Larger establishments may culture strains of starter bacteria, using heat treated milk or skimmed milk. This ensures the absence of harmful bacteria and bacteriophage - a virus commonly found in whey, which attacks and kills the cheese starter bacteria.

ADDITION OF STARTER AND RENNET

5.20 Adding starter culture and rennet presents the following hazards:

failure of starter culture to work properly;
incorrect quantities of starter or rennet added;
introduction of harmful bacteria from personnel or equipment during the addition of starter or rennet.

5.21 You can control these hazards by making sure:

you only buy rennet of a standard specification from a reliable manufacturer;
the milk is at the correct temperature when the starter is added. Too high a temperature can inactivate the culture. Too low a temperature can result in the starter taking too long to act thus allowing harmful bacteria to grow;
the correct amount of starter culture is added. Too much starter will produce a hard, dry, acidic cheese. Too little will result in the acidity of the cheese not developing quickly enough thus allowing harmful bacteria to grow to unacceptable levels;
the milk is at the correct temperature when the rennet is added;
the correct quantity of rennet is added. Too little could result in too high a moisture level in the finished cheese thus allowing favourable conditions for the growth of harmful bacteria. Too much could result in a loss of yield, although this is more a commercial problem than a food hazard. Rennet causes coagulation and contraction, squeezing out the whey: the more rennet, the more contraction, the more whey expelled, the drier the curd;
ensuring that staff involved in cheesemaking maintain a high standard of personal cleanliness and are free from infection, as far as can be ascertained;
ensuring that all the equipment is cleaned and disinfected before use.

SETTING

5.22 This step presents the following hazards:

bacteria entering the process from equipment or the environment;
the starter culture being slow or failing, resulting in the milk staying at too low an acidity for too long and allowing undesirable bacteria to multiply to unacceptable levels.

5.23 You can control these hazards by:

ensuring the cheesemaking premises and all the equipment are properly cleaned;
using an active starter culture at the correct rate;
checking that the acidity of the product is correct within the limits specified for the type of cheese you are making (this will be your main control measure during this stage of the cheesemaking process).

FROM CUTTING THE CURD TO STACKING

5.24 These steps present the following hazard:

microbiological contamination from equipment and personnel.

5.25 You can control this hazard by:

ensuring that all equipment used for cutting the curd is cleaned and disinfected prior to use;
ensuring all staff maintain a high standard of personal cleanliness and are free from infection (see also Part 7 'STAFF HYGIENE').

SALTING, MOULD FILLING AND PRESSING

5.26 The main hazards in carrying out these steps are:

contamination of the curd from the salt or brine solution;
contamination of the curd, salt, or brine from equipment, bandaging or personnel.

5.27 You can control these hazards by:

storing salt correctly in a clean, dry, well ventilated room;
visually checking the salt for foreign bodies, etc., prior to addition;
ensuring that all equipment and bandaging is cleaned and disinfected prior to use;
ensuring all staff maintain a high standard of personal cleanliness;
ensuring that the brine is at least a 50% saturated solution - the stronger the solution, the safer the brine;
removing particles of curd from the brine;
changing or heat treating the brine at frequent intervals.

MATURING OR RIPENING

5.28 Maturing and ripening is a critical stage in the development of the finished cheese. It can be carried out by the maker, an 'affineur', or the retailer. Important points to note are:

generally a high humidity is required, above 85% Relative Humidity (RH). If humidity levels fall, remedial action should be taken. This can include the use of a humidifier, the placing of buckets or trays of potable water above floor level in the store, or covering cheeses with a clean cloth or paper;
the temperature at which cheese needs to be matured or ripened varies considerably from cheese to cheese (not only the style of cheese, but also the individual maker, and even different days' production). Other factors include the stage in the maturing or ripening process, and the timescale in which it is desired to mature or ripen the cheese. A guide to the correct temperatures for maturing or ripening different varieties of cheese is contained in Annex D;
cheeses should be turned frequently in order to keep the moisture evenly distributed throughout the cheese: in the early stages this may be daily, reducing to monthly for older, mature cheeses;
some cheeses grow a surface mould as part of their ripening process: this should be encouraged;
if mould is not required, clean cheeses as appropriate, e.g., by using a salt solution, to remove the unwanted growth;
some cheeses do not necessarily mature or ripen in chronological order: experience will dictate which batches are for first use;
you should remember that views vary on the state of maturity of a cheese, and customers' views may not coincide with your own.

5.29 The growth of undesirable bacteria or mould where not required can occur if:

cheese is stored at the wrong temperature and/or humidity;
storage time is insufficient to allow the cheese to mature or ripen properly;
bacteria and/or mould enter the cheese from storage shelves or the environment;
pests enter the maturing area and contaminate the cheese.

5.30 You can control these hazards by:

storing the cheese at an appropriate temperature which allows it to develop the desired flavour and texture, while minimising the growth of undesirable bacteria (the recommended temperature is generally less than 15^oC - see Annex D);
storing the cheese at the correct humidity for that particular variety of cheese. Where the growth of mould is undesirable a low humidity is necessary, e.g., for Cheddar. A higher humidity is necessary where mould growth is to be encouraged, e.g., for blue veined cheeses, Brie, Camembert;
storing the cheese for the correct length of time for that particular variety;
ensuring the maturing room is kept clean and the storage shelves are clean. Having written cleaning schedules for the maturing or ripening area and ensuring they are followed will help;
maturing mould ripened cheese separately from other varieties;
having a pest control system in place to prevent pests entering the maturing area and contaminating the cheese.

SHELVING

5.31 The SCA recommends wooden shelves as most suitable for the storage of cheeses. You will need a derogation if you wish to use wooden shelves in direct contact with cheese: see Part 8 for details. Such shelves need to be of close grained wood, free from cracks which can harbour cheese mites, and must be cleaned and disinfected regularly.

CHEESE MITES

5.32 Cheese mites look like tiny glass balls in cracks in wooden shelves. They can be controlled principally by good hygiene in the cheese rooms. Treatment with commercial preparations of pirimiphos methyl, the only approved chemical for killing cheese mites is possible, although some mites may be resistant. The chemical should always be used according to the manufacturer's instructions, for example, to prevent possible taint.

UNWANTED GREY MOULDS

5.33 Unwanted grey moulds (Mucor species and others) are not dangerous, but may spoil the appearance and flavour of cheese. They grow on damp walls especially behind panelling or loose paint, and sporulate overnight. The spores may then establish themselves on soft mould ripened cheeses early in the production process before the desired surface coating has become established. Colonies of Mucor on cheeses can be wiped or brushed off with a strong salt solution. Spores in the air can be controlled by fogging with dilute solutions of appropriate chemicals. Follow manufacturers' instructions for safe use.

PEST CONTROL SYSTEMS

5.34 During the maturing and storage stages, cheese is vulnerable to pests including flies, cheese mites, mice, etc. Steps need to be taken to prevent them entering these storage areas. Systems do not need to be complex. They can involve simple measures such as:

keeping doors closed;
fly screening any open windows where necessary;
ensuring premises are rodent proof, e.g., by fitting doors with closers and making sure rodents cannot enter at the base;
keeping any domestic animals such as cats or dogs out of production and storage areas.

TRANSPORT OF CHEESE

5.35 If you are using vehicles to transport cheese, either to another establishment for completion of the maturation process or to shops for retail sale, the Regulations require that the cheese should be protected during transportation from anything liable to contaminate it or cause it to deteriorate. If you use contract vehicles, make sure they are suitable for the hygienic transport of cheese. Transport should be included in your hazard analysis plan.

5.36 You must take account of the means of transport, the duration of the journey, and the weather when deciding how the cheese might be best protected. Refrigeration is not compulsory, but may be necessary for certain varieties of cheese (e.g., soft or cream cheeses) to keep them at the required temperature. It may also be necessary at certain times of the year when high temperatures may spoil the cheese. It is good practice to have written cleaning schedules for the vehicles, and records of checking.

THE CHEESEMAKING LOG

5.37 The SCA recommends the use of a cheesemaking log. Use of such a log can provide documentary evidence of ingredients, their usage rates, and stages in the process. It enables a direct comparison of the end product quality with the raw materials and processing. The log can also provide a written record of testing and results. It enables each batch of cheese to be directly identified with the milk supply and other ingredients used.

5. 38 It is good practice to extend the log to include coding or traceability systems, thereby identifying each cheese from raw material source through to finished product. To assist this process, consider labelling cheeses. A label containing details of production can be attached to the muslin or bandaging after removal from moulds. Such a system might also be extended to the shelves of maturing rooms.

5.39 While a log cannot replace the full hazard analysis process, it can form a useful part of the cheesemaker's hazard analysis plan. Examples of cheesemaking logs for a soft mould ripened cheese and also for a Cheddar cheese can be found in Annex E. Further examples can be obtained from the SCA.

VACUUM PACKING

5.40 If you are considering this form of packaging, expert advice should be obtained. If carried out incorrectly there are potential food safety risks, as vacuum packing alone will not prevent the multiplication of harmful organisms.

SPECIALIST CHEESEMAKERS' ASSOCIATION QUALITY ASSURANCE SCHEME

5.41 Members of the SCA may take part in a quality assurance scheme. Compliance with this Code, by annual self certification against an agreed checklist, is a requirement of the scheme. Spot checks may be carried out by the Association's consultants. Contact the SCA for details.

Specialist Cheesemakers Association 17 Clerkenwell Green London EC1R 0DP

Tel: 020 7253 2114 Fax: 020 7608 1645 Email: info@specialistcheesemakers.co.uk