Periodical Tests It is necessary that checks should be made at regular intervals for the presence of arsenic, lead and iron in dehydrated products Metal abrasion is often a source of contamination in a product. This can arise from various items of plant and equipment, hence the necessity for using stainless steel in food handling machinery as far as possible, particularly at the he process. Galvanized iron is sometimes resorted to for equipment in contact with the dry material, mainly on grounds of cost, but this should be kept to a minimum, in view of the contamination risk Arsenic contamination can arise from flue gases, where a direct system of heat is used, but, if proper attention is paid to the use of correct fuels, and the hot air supply is kept clean, this should not give rise to serious problems SPECIFICATIONS Finally, a set of specifications must be established by the technical staff, to cover every product to be handled. It is the duty of the laboratory staff to acquaint production personnel with these specifications, and then evaluate the production samples for compliance Obviously, it is of paramount importance that there is no undue delay in arrying out quality control tests, and it is vital that these run continuously and concurrently with the 24 hour production schedule. Failure to maintain a round-the-clock check can mean considerable quantities of material being turned down as substandard because they do not meet the specification. This can be very costly to the dehydrator, as a salvage operation is not always easy or practicable. Liaison between quality control and production is, therefore, of paramount importance and this cannot be overstressed Bacteriological specifications may well vary, according to the demand of the customer, but the following specification would be generally accepted as the norm Meat Products: Total Count 5000 pet, rom 0.16 Escherichia coli-absent Salmonella species-absent in 25g Vegetables: Total Count,000 per g Maximum Yeast and mould count: 200 per g Bacillus coli-absent from 0. 1g Salmonella species: absent in 25g The complete specification, therefore, will appear under the following headings, against which the Laboratory will report on batch ofPeriodical Tests It is necessary that checks should be made at regular intervals for the presence of arsenic, lead and iron in dehydrated products. Metal abrasion is often a source of contamination in a product. This can arise from various items of plant and equipment, hence the necessity for using stainless steel in food handling machinery as far as possible, particularly at the 'wet' end of the process. Galvanized iron is sometimes resorted to for equipment in contact with the dry material, mainly on grounds of cost, but this should be kept to a minimum, in view of the contamination risk. Arsenic contamination can arise from flue gases, where a direct system of heat is used, but, if proper attention is paid to the use of correct fuels, and the hot air supply is kept clean, this should not give rise to serious problems. SPECIFICATIONS Finally, a set of specifications must be established by the technical staff, to cover every product to be handled. It is the duty of the laboratory staff to acquaint production personnel with these specifications, and then evaluate the production samples for compliance. Obviously, it is of paramount importance that there is no undue delay in carrying out quality control tests, and it is vital that these run continuously and concurrently with the 24 hour production schedule. Failure to maintain a round-the-clock check can mean considerable quantities of material being turned down as substandard because they do not meet the specification. This can be very costly to the dehydrator, as a salvage operation is not always easy or practicable. Liaison between quality control and production is, therefore, of paramount importance and this cannot be overstressed. Bacteriological specifications may well vary, according to the demands of the customer, but the following specification would be generally accepted as the norm. Meat Products: Total Count 5000 per g. Escherichia coli - absent from 0.lg. Salmonella species - absent in 25g Total Count - 50,000 per g. Maximum Yeast and mould count: 200 per g. Bacillus coli - absent from 0.lg. Salmonella species: absent in 25g Vegetables: The complete specification, therefore, will appear under the following headings, against which the Laboratory will report on every batch of material: 237