Import Control and Food Safety Guidelines
Code of Hygienic Practice for Aseptically Processed and Packaged Low-Acid Foods
Aseptic processing and packaging of low-acid foods is a complicated food manufacturing process. It requires careful control at all stages of production with a view to producing safe and wholesome foods, and it is well known that the control system embraces a large number of inter-related operations. This Code of Hygienic Practice is prepared by the Centre for Food Safety of the Food and Environmental Hygiene Department following consultation with the trade and relevant organizations. It is intended to provide a fundamental guide as to the operation of the aseptically processed and packaged low-acid foods and to advise on the measures necessary to produce safe and wholesome low-acid foods.
Food Processors who wish to discuss any aspect of this Code may contact the Communication Resource Unit (Tel No.:2381 6096) of the Food and Environmental Hygiene Department.
Commercially sterile foods are processed and packaged in a manner that leaves the food free of microorganisms of public health significance, and prevents the growth of any microorganism under normal non-refrigerated storage condition and distribution. This may be accomplished by aseptic processing and packaging.
Aseptic processing and packaging refers to a technique in which food is commercially sterilized outside the package, cooled and aseptically filled in a previously sterilized package, followed by hermetical sealing with a sterilized closure in an atmosphere free from microorganisms. The end product is a hermetically sealed container holding sterile food, which can be stored for prolonged periods of time at ambient conditions.
According to the acidity, foods may be divided into low-acid foods and acid foods. Low-acid food means any food, other than alcoholic beverages, where any component has a pH value greater than 4.6 after heat processing. These foods are considered perishable as pH above 4.6 may support growth of food spoilage or poisoning microorganisms such as Clostridium botulinum. A good manufacturing practice is essential to ensure the safety and quality of these food products.
Aseptic processing and packaging of low-acid foods is a complex food manufacturing operation. It requires careful control at all stages of production to produce and maintain the asepsis of the food processing, filling and packaging systems. The control system embraces a large number of operations which are inter-related. The objectives of this Code are to provide general guidelines as to the operations of aseptically processed and packaged low-acid foods and to advise on the measures necessary to produce safe and wholesome low-acid foods.
- This Code of Hygienic Practice contains the minimum general hygiene requirements for the handling, storage and processing of low-acid foods aseptically packed in hermetically sealed containers. It does not apply to those low-acid foods in hermetically sealed containers processed by conventional canning procedures nor to those that require refrigeration for their preservation. Because of the presence of wide variety of products and packaging systems, it is also the responsibility of food processors to develop precautions tailored for their specific production processes and ensure that these precautions have been taken effectively and efficiently.
- This Code should be read in conjunction with appropriate texts and manuals on the subjects, as well as the various food legislation listed under the Public Health and Municipal Services Ordinance, Cap. 132.
Establishment: Design and Facilities
- The design and facilities of the establishment producing aseptically-packed low-acid foods should be in compliance with the licensing requirements and conditions set forth by the Food and Environmental Hygiene Department.
- All refrigerated spaces within the establishment should be equipped with temperature measurement or recording devices.
Establishment: Hygienic Processing Requirements
Raw Material Requirement
- The processor should establish procedures to ensure that incoming raw materials and ingredients are not used or processed until they have been inspected or verified by the supplier or the processor as complying with specifications.
- The processor should establish and maintain records which provide evidence that the raw materials and ingredients have been inspected and verified.
- Raw materials and ingredients should be stored, maintained and handled under conditions that will prevent spoilage, protect against contamination and minimize damage. Stocks of raw materials and ingredients should be properly rotated.
Packaging Material and Product Containers
- All packaging material for packing low-acid foods should be stored and handled in a clean and sanitary manner to minimize the chance of contamination or damage. The material of product containers should be appropriate for the product to be packed and sufficiently durable to withstand the processing and subsequent handling strains to which the containers are normally subjected. The sealant material chosen must be compatible with the product as well as the container and closure systems.
- Both the container manufacturer and the food processor should develop appropriate sampling and inspection schemes to ensure that containers and closures are in compliance with the agreed specifications.
- Scheduled processes for processing aseptically-packed low-acid foods must be established with scientific methods by competent personnel. Any changes in product composition and formulation must be evaluated as to their effects on the adequacy of the process. If the scheduled process is found to be inadequate, the thermal process must be re-established.
- All critical factors specified in the scheduled process should be measured, controlled and recorded at intervals of sufficient frequency to ensure that these factors remain within the specified limits in the scheduled process.
- Each product sterilizer should be equipped with a sufficient number of suitably located temperature indicating devices. The temperature indicating devices should be accurate, calibrated and checked for accuracy against a known standard prior to installation and thereafter at least yearly. Records of accuracy checks which specify date, standard used, methods used, and person performing the test should be maintained. A daily inspection of temperature indicating devices should be made to detect and replace defective devices.
- Each product sterilizer should be equipped with a sufficient number of accurate, calibrated, reliable temperature/time recording devices which are used in conjunction with the reference temperature indicating devices. The recorder should agree as closely as possible (preferably within 0.5oC) and should not be higher than the temperature indicating devices(s) during sterilization. The temperature/time recording devices should be standardized and calibrated upon installation and at least yearly thereafter.
- Where a product-to-product regenerator is used to heat the cold unsterilized product entering the sterilizer by means of a heat exchange system, it should be designed, operated and controlled so that the pressure of the sterilized product in the regenerator is greater than the pressure of any unsterilized product. This ensures that any leakage in the regenerator will be from the sterilized product into the unsterilized product. The pressure should be continuously monitored and recorded.
- The hold section, if present, of the sterilizer should be designed to give continuous holding of the product, including particulates, for at least the minimum holding time specified in the scheduled process. An appropriate method should be used to control the production feed rate specified in the schedule process.
- Prior to the start of aseptic processing operations, both the product sterilizer and all product contact surfaces downstream should be brought to and maintained in a condition of commercial sterility throughout production.
- In the event of loss of sterility due to temperature in the holding section dropping below the scheduled minimum, the product in the holding section and any downstream portion affected should be directed to recirculation or waste and the system should be returned to a condition of commercial sterility before resuming operations.
- Prior to the initiation of product filling, the aseptic zone of filling and packaging equipment must be brought to and maintained in a condition of commercial sterility throughout the entire production run by appropriate physical or chemical means. The aseptic zone should be re-sterilized when conditions occur which may result in a loss of sterility.
- Packaging material, preformed containers and their closures should be sterilized using appropriate methods as specified in the scheduled process before product filling.
- Appropriate inspections and tests at intervals of sufficient frequency should be carried out to monitor the sterilization of packaging materials and maintenance of sterility of the aseptic zone of the packaging machine.
- The filling of containers should be controlled with a view to meeting the filling and headspace requirements as specified in the scheduled process.
- During production runs, appropriate visual inspections and tests of the container closure should be conducted by competent personnel at intervals of sufficient frequency to ensure consistent reliable hermetical sealing. All pertinent observations should be recorded.
- If closure defect is detected, which may result in a loss of hermetic integrity, all products produced between the discovery of the fault and the last satisfactory check should be identified and assessed. All corrective action taken subsequent to the discovery of the defect should also be recorded.
- Each container should be marked with an identifying alphanumeric code, spelling out critical production data such as production location, date, hour, machine number, etc. The code is of vital importance should there be a future need for a recall.
- The finished product should be handled, stored and transported under such conditions as will preclude the contamination with and/or proliferation of microorganisms and protect against deterioration of the product or damage to the container.
The processor should ensure that all general hygienic practices in the handling (including preparation, processing, packaging, storage, transport and distribution) of food should be in compliance with Part V of the Public Health and Municipal Services Ordinance Cap. 132 and its relevant subsidiary legislation, and the licensing requirements and conditions set forth by the Food and Environmental Hygiene Department.
Staff working in a food handling area should receive adequate and continuing training in operation, in hygienic handling of food and in personal hygiene so that they understand the operation guidelines and the precautions necessary to prevent contamination of food.
A formal cleaning and disinfection procedure, based on equipment and chemical suppliers' recommendations, should be developed to ensure all equipment and areas are thoroughly and appropriately cleaned. The procedure should indicate how cleaning is to be done (manually and/or CIP), as well as the type, concentration, contact time, temperature, pressure (flow rate), method of delivery and other critical factors of cleaning compounds for each piece of equipment. All cleaning and sanitizing procedures as well as housekeeping activities should be documented.
A quality assurance program (such as the Hazard Analysis Critical Control Point (HACCP) system) covering all aspects of production, storage and transportation should be established to ensure the finished products in compliance with the scheduled process.
Incubation tests (for example, 10 days at 35oC± 3.0oC) should be conducted on a representative sample of product from each lot. Other time/temperature combinations may be chosen by the processor. Incubated containers should be observed to detect gas production and changes in product appearance (for example, odour, pH, viscosity, etc.). Microbial analyses for commercial sterility should also be conducted on a given number of containers from each lot regardless of the absence of signs of non-sterility following incubation. Records of the test results should be maintained.
Permanent, legible and dated records should be maintained. Examples of such records are:
raw material quality records,
pre-processing procedure records,
machine operator and/or automatic records of:
aseptic packaging, etc.
process deviation records,
finished product testing records,
storage records (storage waste, storage control),
cleaning and disinfection records, etc.
Each entry of the record should be made by the processing system operator, or designated person, at the time the specific processing system condition or operation occurs. All records should be reviewed at the appropriate time interval by a designated individual. Any out-of-specification observations or results should receive follow-up action and such action should be recorded. All records should be held in a manner which will permit ready reference.
Prior to release for product distribution a competent representative of plant management should review all processing records to ensure all products received the scheduled process. Any unusual observations should receive appropriate follow-up action.
The processor should supply the distributor with written guidelines on product storage, handling and transportation. Personnel handling the product should be informed of the inherent risks of rough handling.
The processor should report to the Food and Environmental Hygiene Department any instance of contamination with microorganisms, spoilage or process deviation the nature of which indicates potential health significance where any lot of such food has in whole or in part entered distribution.
A product recall (emergency) plan should be developed to effectively and efficiently retrieve from the marketplace any lot of the finished product which may pose a safety hazard to consumers. The recall plan should be test run to determine its effectiveness. The Food and Environmental Hygiene Department has produced a publication entitled Food Recall Guidelines which serves to provide guidance to food manufacturers and distributors on carrying out food recalls.
Compliance Checklist for Aseptically Processed and Packaged
- Design and facilities are in compliance with the licensing requirements and conditions set forth by the Food and Environmental Hygiene Department.
- Temperature indicating devices have been installed in all refrigerated spaces.
- Raw materials are in compliance with specifications.
- Raw materials are properly stored and maintained on premises to prevent cross-contamination and spoilage
Packaging materials and product containers
- Packaging materials are stored and handled in a clean and sanitary manner.
- Product containers and closures are in compliance with specifications.
- Scheduled processes have been established with scientific methods.
- All critical factors are measured, monitored and recorded at intervals of sufficient frequency.
- Temperature indicating devices are properly installed in sterilizers, and are monitored during the sterilization cycle to ensure that the cycle is maintained at the proper sterilization temperature.
- Producer sterilizers are equipped with temperature recording devices to record the sterilizing temperature.
- The pressure of the sterilized product in the product-to-product regenerator, if present, is greater than the pressure of unsterilized product.
- Hold tubes of the sterilizer, if present, are designed to give the product for sufficient holding time specified in the scheduled process.
- A sterilizing programme for all product sterilizers and product contact surfaces has been established and implemented.
- A sterilizing programme has been established and implemented for the aseptic zone.
- A sterilizing programme has been established and implemented for the packaging materials.
- An inspection programme has been established and implemented to monitor the sterility of packaging materials and aseptic zone.
- Production filling is in compliance with specifications.
- An inspection programme has been established and implemented to monitor the sealing of the container closure.
- Containers are marked with identifying code.
- The finished product are carefully handled, stored and transported to prevent contamination and deterioration.
- Equipment has been maintained properly, meeting suppliers' requirements.
- All general hygienic practices meet the various legislation under the Public Health and Municipal Services Ordinance, and the licensing requirements and conditions set forth by the Food and Environmental Hygiene Department.
- A cleaning and disinfection procedure has been established and implemented. The procedure indicates all critical factors of cleaning compounds (e.g. type, concentration, contact time, temperature, etc.) as well as how cleaning is to be done (e.g. manually and/or CIP).
- All packaging material and equipment used in food preparation are clean and sanitized before and after production.
- A training program has been established and implemented to provide technical training to all food handlers.
- A quality assurance program has been developed.
- A sample of product from each lot has been assessed (e.g. incubation at a pre-determined time/temperature combination) to determine the safety and quality of the product.
- Permanent records (including preparation, processing, packaging, storage, transport, distribution, training, maintenance, etc.) of the scheduled process are maintained.
- A recall plan has been developed.
- A person has been nominated to initiate and co-ordinate the recall activities.
- The recall plan has been test run.