QUALITY AND PROCESS CONTROL IN THE FOOD INDUSTRY
Pearl Adu-Amankwa
Food Research Institute, P.O. Box M.20, Accra.
Published in The Ghana Engineer, May 1999
Reprinted with GhIE permission by the African Technology Forum
ABSTRACT
Controllable factors that either positively or negatively influence the finished product are referred to as the quality control. The use of good and sound raw material is of primary importance for the achievement of the required end product of consistent quality. Identification of die critical points is essential since the process control relates to die processing results of the raw material. Traditional quality control is completely unable to eliminate quality problems, thus a preventive strategy based on thorough analysis of prevailing conditions which ensures that objectives of the quality assurance programme are met is recommended for the food industry. The Hazard Analysis Critical Control Point (HACCP) and Total Quality Management (TQM) embody these requirements as certified under the International Standard Organisation (ISO) 9000 series.
1.0 INTRODUCTION
Quality control is the sum of all those controllable factors that ultimately influence positively or negatively the quality of the finished product e.g. selection of raw materials, processing methods, packaging, methods of storage distribution etc. Quality is defined as any of the features that make something what it is or the degree of excellence or superiority (1). The word "quality" is used in various ways as applied to food. Quality product to the salesman means one of high quality and usually at an expensive nature e.g. champagne is considered a quality as compared to fish and chips. Likewise for fresh produce, the word "quality" refers to the attributes of the food which make it agreeable to the person who eats it. This involves positive factors like colour, flavour, texture and nutritive value as well as the negative characteristic such as freedom from harmful micro-organisms and undesirable substances.
The term control does not imply that a poor raw material can be converted into a good finished product. In food processing, the general rule is that the effective methods must be carefully applied to conserve the original qualities of the raw materials. Processing cannot improve the raw material.
The aim of quality control is to achieve as good and as consistent a standard of quality in the product being produced as is compatible with the market for which the product is designed. (2)
2.0 THE PRINCIPLES OF QUALITY CONTROL
The principles of quality control are considered under the following:
· Raw material control
· Process control
· Finished product inspection
Invariably, once a food product has been through a manufacturing process, little can be done to alter its quality. Thus examination of finished products only permits acceptance of material reaching the desired standard and rejection of material which fails to reach this standard. Such a process is therefore one of inspection and not one of control. It can be claimed that if control of raw materials and control of process is perfect, the final product will not require inspection. However, in practice it is seldom possible to guarantee complete control over raw materials and processing conditions and thus a greater or lesser degree of finished product inspection will be necessary, depending on circumstances within the factory. it is economically desirable to concentrate on ensuring that inspection (and rejection) at the finished product stage is reduced to a nominal level by effective raw material and process controls.
In a food processing industry the stores and warehouses often contain a large range of raw materials. Raw materials such as artificial colouring, spices and essences may be used slowly and may deteriorate on long storage. Others such as wheat or milk powder may be rapidly replaced in the flour and milk industry respectively. Fresh meat is highly perishable and requires good refrigeration where sugar, salt etc. may be very stable and only requires a cool dry condition to remain in excellent condition for a long period. It's not every single raw material which must be subjected to detailed examination and testing at frequent intervals. Those used in insignificant amounts can be omitted from frequent inspection since the cost of inspection will often far outweigh the advantages gained.
In any product, there is a dominant raw material (sometimes it could be several of these) upon which the quality of the finished product is mainly dependent e.g. in bread production, flour is the essential raw material, malt for beer, wheat for flour etc.
3.0 RAW MATERIAL SELECTION AND PRODUCT QUALITY
The following are the rules of quality control:
I. The dominant raw material (s) are selected for priority of attention
2. The selected raw materials are tested in relation to their contribution to product quality.
3. The raw materials tested are released from the stores only after the test results
have been properly recorded.
4. Process control must relate the processing results to the raw materials test.
5 Define the critical points in the process and concentrate on these.
6. Finished product inspection should be reduced to the minimum level compatible with
the confidence justified by the raw materials and process control.
7. Quality control is effective in proportion to its degree of integration into the overall
organisation of the factory.
The formulation of the type of sampling and the test applied must reflect in the finished product. The test must be fast, simple and suited to the purpose but the same time reliable to enable the laboratory to give authorization to the factory to use the raw material. This test can be chemical, physical, bacteriological or organoleptic.
Careful planning is necessary for release of raw test results. The factory must not be deprived of an essential raw material while it awaits quality control clearance. Pressures of production are invariable high and nothing brings a quality control system more quickly into disrepute than delays while testing is carried out. When there is good cooperation management delays can be avoided. This means that the work of quality control must be integrated with the factory management plan.
It is evident that raw material control and process control arc inter-related. It is difficult to discuss raw material control without reference to process control and it is also equally difficult to talk of process control without assuming that proper raw material controls are simultaneously in operation and that the dominant raw materials are known to have reached the standards required for proper processing.
In planning a process control scheme, one must first and foremost list in sequence the steps in the process and put it in a flow diagram. Each step is considered critically and against it sources of deviation is prepared. From this list a number of points in the process will be recognised as critical points (CP) at which trouble may arise which may be reflected in the quality of the finished product.
The flow sheet stimulates thought on matters of detail which might otherwise be missed and thus provides new ideas for avoiding difficulties. Against each critical point, list immediate steps which may be taken to reduce variation together with further ideas which could be adopted at a later stage to eliminate it completely. The success of any quality control system depends on the sympathetic interest of top management. The initiative system must come from the top management. It is useless merely to instruct a laboratory to start a quality control system unless management at all levels from Managing Director to shop foreman is prepared to accept it and to co-operate in its implementation.
Quality control is one aspect of the overall control production which in its totality, constitutes the management function. Stock control, production management, plant maintenance and sales budgeting are terms used by management to describe activities directed towards achieving the purposes of the organization within the limits of its resources. The concept behind the terms used is the coordinated direction of efforts towards an idealized optimum situation in which maximum results are achieved with minimum effort. As society becomes more complex, management activities may be directed not merely to achieving the maximum profit as shown in the annual accounts in any years, but to producing what might be described as a situation of profit growth.
An example of this would be a decision to raise a quality standard at the expense of an immediate reduction in profit level with the anticipation that improved demand will more than counter-balance this profit reduction in the near future.
It is apparent that traditional quality control is completely unable to eliminate quality problems as such a preventative strategy based on thorough analysis of prevailing conditions which provides assurance that objective of the quality assurance programme are met. This has been developed into the Hazard Analysis Critical Control Point (HACCP) system (3). This primarily aims at guaranteeing food safety but can easily be extended to cover spoilage economic fraud. The latest quality systems, such as certification under an International Accepted Standard (ISO 9000 Series) and Total Quality Management (TQM) [are those] in which everybody in an organisation is fully committed to achieving all aspects of quality. These days national food legislations place total responsibility for food quality on the producer (4).
3.1 Main elements of the HACCP system
The main elements of the HACCP system are:
1. Identify potential hazards. Assess the risk (likelihood) of occurrence.
2. Determine the Critical Control Points (CCPs). Determine steps that can be
controlled to eliminate or minimise the hazard.
3. Establish the criteria (tolerances, target level) that must met to ensure that CCP is under control.
4. Establish a monitoring system.
5. Establish the corrective action when CCP is not under control.
6. Establish procedures for verification.
7. Establish documentation and record keeping.
Hazards have been defined as the unacceptable contamination growth and survival of bacteria in food that may affect safety or quality (spoilage) or the unacceptable production or persistence in foods of substances such as toxins, enzymes or products of' microbial metabolism (5).
Simply it is a biological, chemical or physical property that may cause a food to be unsafe for consumption.
4.0 HACCP
We have an HACCP system so that there is an increase in probability of 'Right first time' every time. It facilitates the ability to customers and trade across barriers. The customer's confidence is not only increased but it shows the diligence of the manufacturer leading to constant improvement and ability to seek third party certification
ISO 9000 series (6) is identified to British standard 5750. ISO 9000 series do not set standards for you, nor tell you how and where to measure them but it provides the normal legal and safety requirements. These standards are set by the company. The good news is HACCP can and does interface with ISO 900. Other series are ISO 9001,9002, 9003 and 9004. (7,8,9,10)
4.1 Critical Control Point (CCP)
This should be identified and carefully chosen on the basis of risk of severity of the hazard, where severity means the seriousness of the consequences when a hazard occurs and risk is and estimate of the probability or likelihood of a hazard occurring. It is only the risk which can be controlled. The CCP may be a location, procedure or processing step at which hazards can be controlled. Two types of CCP may be identified.
· CCP1 ensures full control of control of hazard, whilst
· CCP2 minimises but does not assure lull control.
At the CCP, the hazard can be prevented, eliminated or reduced to acceptable levels. The CCP should truly be critical. Some of the CCPs are there as a result of company rules for good manufacturing practice, product reputation, company policy.
The HACCP concept sets priorities on risks and emphasizes operations that offer the greatest potential for control. Example of CCPs are a specified heat process, chilling, specific sanitation procedures, preventive of cross-contamination, and adjustment of food to a given pH or NaCl solution.
4.2 Criteria for target levels and tolerances for each CCP
A detailed description of all CCPs is necessary for effectiveness. This includes determination of criteria and specified limits or characteristics of a physical or biological nature such as time and temperature. Other known criteria such as pH and moisture level can be obtained from technical literature; however, the HACCP team needs to define the processing conditions for obtaining safe food.
It is insufficient to state that internal temperature of a food should arrive at a certain temperature. The precise operation to obtain the said target level using the available equipment must be determined and the level of tolerance established. Equipment and instruments used for control functions must be kept under strict control and the performance must be validated regularly. In monitoring the measure should accurately identify and choose factors which control a CCP. It should be simple, give a quick result, be able detect deviations from specifications and criteria (loss of control) and finally, provide this information in time for corrective action to be taken.
The effectiveness of control should be preferably monitored by visual observations or by physical and chemical testing. Microbiological methods are usually used to randomly verify the effectiveness of control of all CCPs, e.g. verification of hygiene and sanitation controls. Monitoring involves record keeping, data collection and trend analysis. A simple but effective data collection (monitoring) activity and forms should be designed. These records are the tools which management and outside inspectors will use to ensure operations are within specifications.
The system must allow for corrective action to be taken immediately when the monitoring results indicate that a particular CCP is not under control and action must be taken before deviation leads to a safety hazard. This corrective action involves four activities, i.e.
One person must be designated the with responsibility to adjust the process and to inform others with non-compliance products, after testing those that meet the standards are diverted to safe use, whilst the substandard products are either reprocessed or destroyed depending on the degree of sub-standardisation.
Verification is used to check whether HACCP system is working. Here random sampling and analysis is used or even shelf life or incubation test for sterile products. This could also be done by outside parties e.g. government authorities such as Ghana Standard Board (GSB), Food Research Institute (FRI), trade partners, consumer organisation etc. The approved HACCP plan and associated records should be on the file. Documentation of all procedures at all steps is essential with all documents being assembled in a manual and available for inspection by regulatory agencies. The head of quality assurance takes paramount responsibility for the general and overall operations of system, though the first step is for top management to be firmly committed.
In a large food factory the team will be multi-disciplinary that is, a microbiologist, processing specialist, chemist, biochemist, engineer, packaging technologist, sales, staff, training and personnel managers. For medium and small scale, the quality control and production managers and few supporting staff like sales and administrative managers should be enough. If they do not have qualified personnel on the payroll, they must prepared to buy assistance from outside consultants in order to implement the system. When the team is assembled, their terms of reference must be clearly defined and agreed by the group.
A detailed description and specification of the production must be provided to the team. This includes technological aspects including preservatives parameters (NaCl, pH, organic acids, colour etc.). The intended storage temperature packaging technology and intended use of product should be clearly stated. The processing technology ingredients list, a precise flow diagram and description of cleaning and sanitation procedures must be documented.
A visit to the processing site to verify and fully understand the process flow diagram is necessary facilities and equipment designs must be inspected to obtain information on the possibility of additional hazard related to these aspects e.g. layout, traffic pattern of people, equipment properly sized for volume of food to be processed.
Quality control managers and supervisors can improve the date upon which yields are calculated by using the knowledge of the properties of in-coming raw materials. On the other hand, production control, with its detailed knowledge of movements of materials may provide information of value in improving quality control's sampling methods, etc. However, good personal relations between those concerned are essential if co-operation is to be obtained.
In personal relations the head of the quality control department has a special responsibility. He is usually a graduate and may have enjoyed a better education than some of his colleagues. This situation sometimes creates a mistrust or suspicion, which may be increased by an impression that the quality control staff are a police force introduced by management to ensure that others are doing their job properly. In this kink of situation, it is the duty of the head of the quality control section to take an initiative in breaking down barriers of mistrust and suspicion. This can neither be done overnight or by flexing one's muscles. Even if you know more than your colleagues, you must avoid dogmatism and condescension.
5.0 CONCLUSION
Quality control is a dynamic concept which evolves from initial plan as experience grows. It scans every day's production. Day-to-day experience of the variables to he met leads sometimes to simplification of original plan. The introduction of improved machinery may also affect the original plan. Year-to-year experience of raw material variability increases the degree of certainty of predictions based on raw material testing. The bacteriological safety of a pack is a factor involving the growth of confidence as experience grows.
In the industrialized world, all food processing is linked to quality control. They do operate systematic quality control scheme. There are lots of mechanized control techniques and these are linked with improvements in processing machinery. Thus, although quality control started with a chemist, it may well be developed by an engineer.
From these considerations, it is tempting to speculate that in the 21st century, there will be a possibility of centralizing all forms of control and using modern data processing methods to obtain an integrated picture of events at any moment during the production schedule, and at the same time to provide continuous monitoring of the schedule to allow very rapid adjustments to fluctuating demand and changing circumstances. It is perhaps not too fantastic to suggest that the manager of the future may sit at a desk provided with dials showing him the sales current level, the current production level, the production efficiency level, the running profit margin and the running quality index. There seems no fundamental reason why such a system could not be devised to process continuous incoming information.
REFERENCES
1. Amerine, M., Pangborn R.M., Roessler- E.B. (1965), Principles of Sensory Evaluation of Foods,
Academic Press.
2. Hawthorn, J. (1967), In Quality Control in the Food Industry, Vol. 1, S.M. Herschdoerfer (ed),
Academic Press.
3. Anon (1972), Proceedings of the 1971 National Conference on Food Protection,
US Government Printing Office, Washington D.C. USA.
4. Huus, H.H. (1994), Assurance of Seafood Quality, FAO Fisheries Technical Paper (334)
5. ICMF (International Commission on Microbial Specifications for Foods) (1988)
Micro-organisms in foods. Application of the Hazard Analysis Critical Control Point (HACCP) system
to ensure microbiological safety and quality. Blackwell Scientific Publications.
6. ISO 9000: Quality Management and Quality Assurance Standards - Guidelines for selection and use.
7. ISO 9001: Quality Systems - Model for quality assurance in design, development, production,
installation and servicing.
8. ISO 9001: Quality Systems - Model for quality assurance in production installation.
9. ISO 9003: Quality Systems - Model for quality assurance in final inspection and test.
10. ISO 9004: Quality Management and Quality Systems Elements - Guidelines.
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