Auditing a flourmill

18 May 20176 min reading

“The quality of the flour is the combination of characteristics that gives the flour its ability to be used in specific products. The art and science behind this ability is the power of each miller. A strong quality management system will help to minimize mistakes and maintain traceability.”


Vasilis SOTIROUDAS Food scientist Control Union Greece

Going to an audit is like going to a fight. But not against the mill quality team as many people think! An audit is a fight against the weaknesses of the building, against the mistakes in the machinery, against potentially poorly designed procedures and sometimes against the wrong mentality of the workers.

And although the audit is a fight, there are no enemies! The QA (quality assurance) team, the workers, the managers and the auditor are all on the same side. When this is accepted then there are more chances for a victory.

WHAT SHOULD WE LOOK FOR? The problems that are associated with flour are very specific:

• The quality of flour does not meet the specs

• There are insects in the flour

• There are foreign objects in the flour

• There are pathogens in flour

Let us look into the potential source of each problem:

The quality of the flour is the combination of characteristics that gives the flour its ability to be used in specific products. The art and science behind this ability is the power of each miller. A strong quality management system will help to minimize mistakes and maintain traceability. The job of an auditor is not to evaluate this art & science. His job is to test if the system keeps good track of the lots and, by doing so, if the customers remain satisfied.

The most common problem associated with flour is insects. It is usually stored product insects that are found inside packed or bulk quantities of flour. The stored product insects live in grain elevators, silos, grain warehouses and flourmills. It is very easy to infest the final product and well-designed & well-respected procedures are needed to keep products and production lines free of infestation.

The auditor should look for:

• Pest proof buildings,

• Inspection of incoming goods,

• Good personnel practices,

• Proper handling of infested material

• Adequate monitoring plans.

PEST PROOF BUILDINGS Among the stored product insects we find insects that fly. These are moths (Lepidoptera) but even some crawling insects (Coleoptera) can fly during the hot season. The flying insects can easily enter a food industry through open doors and windows as some of these insects can survive and even develop outside.

INSPECTION OF INCOMING GOODS Each load of grain or other incoming good shall be inspected for insect presence. Sampling must be performed based on given protocols and a well-trained employee shall carry out the visual inspection. All infested loads must be treated according to the procedures. Even if all procedures are respected at 100 percent, an infested load can enter the facility if only insect eggs are present. This is possible as bad fumigations usually kill the adult insects and some larvae-pupae but the eggs survive. The eggs cannot be easily spotted and sometimes the larvae and pupae can develop inside the kernels. Spotting the infestation becomes almost impossible in some cases. So the inspection of incoming goods starts by selecting the right suppliers and by making sure their quality management is also well maintained.

GOOD PERSONNEL PRACTICES Forgetting a window open, leaving an area poorly cleaned and not inspecting the dead-end of a line may lead to serious infestations. The personnel of a flourmill must be aware of the dangers and the implications of poor employee performance. Training on-the-job should be routinely scheduled and photos of insects shall be shown to all.

CONDITION OF INFESTED MATERIAL Infested material may be found and should be handled according to a strict procedure. We may have infested product returning from the market. We may get an infested delivery of raw material, or packing material or we may find an infestation growing in the mill. In all cases the incident shall record, the case shall be treated, the root cause shall be found and the effectiveness of the treatment shall be evaluated.

MONITORING PLAN Each flourmill shall have a monitoring plan to early detect infestation. The plan shall include pheromone and UV traps that are placed in all areas and they shall be periodically inspected (ideally every 2 weeks, latest every 4 weeks) by a scientist who will recognize the insects and record their numbers per location.

Foreign material in flour could be an issue but technology is offering solutions. Sieves, metal detectors and x-ray machines shall be used as the defending line. The right performance of this line should be the subject of inspection of the internal auditors as these points are regarded as the CCPs of the HACCP system.

Escherichia coli (E.Coli) and Salmonella are among the pathogens that have been found in flour. In 2016 a major US flour brand recalled millions of pounds of flour due to contamination. Although flour has low aw and is not considered a risky food from the microbiological point of view, there are some facts that need to be considered:

• Grains are moved through silos and elevators where these pathogenic bacteria are found.

• There are consumers who like to eat undercooked or raw dough.

Before this specific recall, 42 people from 21 states have been sickened and 11 have been hospitalized. This serious incident gives a clear mark to how important is to monitor the hygienic conditions in all lines and silos.

The points mentioned above set the targets of an exhaustive audit in a flourmill. The audit shall mainly include inspection of the production and storage areas and minimum time in the office. The records must also be inspected but only with random sampling that will last not more than one hour. The rest of the audit-day shall be dedicated to visiting all areas, opening lines, checking the dead-ends, looking for infestation, evaluating the preventive measures and judging the efficiency of employees.

A successful audit would start with the QA team declaring the weaknesses to the auditor and seeking for advice and it would end with a list of points to be improved. A good audit will never have zero findings. A good audit will never have losers. Only winners!

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