Food Safety Alert! – Raw Material Storage

July 31, 2017
Source: Johnson Opoku-Boateng l thebftonline l Ghana
Food Safety Alert! – Raw Material Storage

One of the major factors that affect the quality and safety of prepared or processed food is storage of the individual raw materials that eventually come together to produce that recipe or formulation. The conditions under which food processors store raw materials is critical when the subject of microbial growth, multiplication and even contamination is considered. It is therefore imperative that storage is considered as one of the top priorities when it comes to food safety.



There are several reasons why raw materials need to be stored especially when we consider commercial production. It is in fact advantageous to make provision for storage for all raw materials listed in your recipe or bill of material for manufacturing. Storage is encouraged so that there is provision for production the entire year or at least in the short to medium term. Since there are usually fluctuations in supply, every processor should have a means of storing raw materials to ensure continuity in production. There are times where bulk discounts are given for certain raw materials and it is advisable to take advantage of such deals once adequate storage can be achieved. Storage is also important to maintain the safety, quality and wholesomeness of all raw materials. There are three main methods of storing raw materials and these are storage under ambient conditions, freezing and refrigeration. Every single raw material would be stored under one of these conditions to maintain its safety, quality and integrity.



Ambient Storage

There are certain categories of raw materials which can only be stored under ambient conditions and must be done well enough to avoid contamination and spoilage. Hazards usually associated with storage in ambient conditions include contamination from pests and multiplication of microorganisms due to dampness. Rooms for storage of products under ambient conditions must be adequately cleaned and disinfected. Raw materials that are normally stored at ambient will include staples such as bags of rice, wheat, maize, millet, sorghum, roots and tubers (potatoes, cassava, yams,) etc. Ensure that staple foods are stored on plastic pallets and never on the bare floor. Ensure that pallets are placed about 1.5ft from the walls to prevent pest contamination through feeding on the foods. It is pertinent to have a pest control programme for all food premises to prevent pests from contaminating raw materials. Apart from the fact that rodents carry a host of pathogens on their body, rodent urine is very poisonous.

Canned products should be stored on shelves. Always inspect all canned products for damage, bulging and expiry/best before dates before storing. Any canned product that shows signs of damage, rust or bulging should be discarded immediately. Bulging for example may result from gases produced by some disease-causing gas-producing microorganisms. Ensure that flour, spices and other powdered raw materials are stored in pest-proof containers. Always practice first-in-first-out (FIFO); raw materials already in storage must be used before fresh ones. For products with stated expiry dates, those that are closest to expiry should always be used first.



Freezing is a key storage method that helps keep food safe and in good quality. Although this method is very popular the misuse of freezing has created many food poisoning incidents. There is no way a human being could use his hands to ascertain the actual temperature in a deep freezer, incidentally that is what happens in many food establishments. There are thermometers that can be used to verify the actual temperature in freezers especially those that are not digital. Storage freezers must be thoroughly cleaned and disinfected before storing items in them.


Once storage has begun, it is important to regularly defrost, clean and disinfect freezers before putting them to use again. Raw materials stored in deep freezers include meat such as beef, mutton, pork etc. Poultry and fish are also stored in freezers to maintain their safety and quality. Always ensure that the freezer temperature is at -18OC (negative eighteen degrees Celsius).


Most freezers and refrigerators have regulators that do not follow conventional temperature trends. In many cases the higher number on the regulator is the cold end of the freezer whilst the lower number is the warmest. Conventionally the lower the figure the lower the temperature. Hence 7OC (seven degrees Celsius) cannot be colder than 1OC (one degree Celsius). It is therefore presumed that the regulators in our normal refrigerators and freezers are only there to indicate the strength of cooling and not temperatures. Hence every food processor should have thermometers to always confirm the right temperatures in order to preserve food. It is recommended that food processors invest in freezers and refrigerators that have digital thermometers with alarms in order to have it easy monitoring temperatures.

Freezers are not supposed to be overloaded with products as it is seen in many businesses. Overloading freezers affect the temperature profile of the freezer usually sending them up, thereby encouraging microbiological growth and multiplication. Defrosting regularly is important to maintain the efficiency of the freezer.



Refrigeration is usually employed when storage is not going to be extended compared to freezer storage. Most perishable foods are stored under refrigeration and the target temperature is 1 – 4OC. Food processors must be aware that, just like freezing, raw materials have to undergo cleaning and in some cases disinfection before storing in refrigerators. Fresh perishable fruits and vegetables such as oranges, melons, tomatoes, lettuce, cabbage etc. need to be washed thoroughly and bagged before storing in refrigerators. This helps reduce the number of microorganisms on them from the source. Refrigerators need frequent defrosting, cleaning and disinfection. The frequency will depend on what it is used for and how quickly it becomes dirty. In very large organizations cold rooms are built, where the first chamber serves as the refrigerator and the second serves as a freezer. Since these are rooms, the strictest personal hygiene needs to be observed by workers. Foot sanitizers need to be installed at the door of the cold room to avoid workers contaminating the floors. Hairnets and hygienic protective clothing must always be worn by workers.



Storage is important in manufacturing, especially in food processing. Although the economic advantages have been highlighted, it is the safety and quality disposition of raw food items that makes storage very critical. There are several food safety incidents that can be attributed to the improper storage of raw materials. Knowledge of the effects of improper storage is therefore pertinent to preventing such food safety incidents. Whichever storage method is used, there are basic rules to follow and this must be engrained into the DNA of the hygienic culture of the business.


Johnson Opoku-Boateng is the Executive Director & Lead Consultant, QA CONSULT (Consultants and Trainers in Quality Assurance, Health & Safety, Environmental Management systems, Manufacturing Excellence and Food Safety). He is also a consumer safety advocate and helps businesses with regulatory affairs. He can be reached on +233209996002, email: