Prior to starting the production of acidified foods, the processor must register the establishment or processing facility with FDA. The specific products and procedures used to manufacture the final products, called “schedule processes” must also be filed with FDA. In addition, the processor must complete a training program called the “Better Process Control School” or equivalent before engaging in commercial production. This program is offered annually in May by Cornell University and at different dates by other schools. Most likely the processor will need the assistance of a “Process Authority” to develop or verify the schedule process and to help with the filing and documentation requirements. CFVC has several Process Authorities that will work with you during this stage.
Acidified foods must be properly acidified to a pH below 4.6, but in practice this value is usually 4.2 or below for safety reasons. The regulations also require a thermal process or heating step to kill all the pathogens and any other spoilage microorganisms that could grow during the shelf-life of the product. To assure quick and proper acidification, the food is normally cooked or heated with the acid before being filled into the final container. The pH is checked, controlled and documented prior to filling and closing. The heating or pasteurization step or process must be done either by hot-filling the product or by the boiling water bath process. The heating temperature and time are critical factors that must be monitored, controlled and documented. The final equilibrium pH is checked and documented after the product has received the heating step. Any other critical safety factors must be monitored, checked and documented as specified by the schedule process.
To measure the pH, the processor must use a pH meter with two decimal places accuracy if the final pH is 4.0 or above. A pH meter is the best method to measure pH and it is recommended for all products and values. If the pH is below 4.0, other methods can be used such as pH paper or a pH meter with one decimal place.
Containers for acidified foods should be such that a hermetic seal is obtained. The best containers are cans and glass jars/bottles with metal caps lined with a compound called plastisol. With these closures, a good vacuum is obtained. Vacuum is a good indicator of a hermetic seal and helps to keep the quality of the product.
References: Code of Federal Regulations. Title 21 part 114. Office of the Federal Register, National Archives and Records Administrat