Quality Control and Hygiene

From inspection to assurance

Quality control once meant, above all, a microbiological test on the finished product. The method has a weakness at its root. The result comes back days later, and by then the gelato has been sold and eaten. A problem found at that point can no longer be acted on. It is an autopsy, not a prevention.

So the thinking turned. But it was not a replacement. The turn happened along two lines at once.

One line moved the control onto the process. Rather than examine the finished product alone, control every step from raw material to serving, and hold the danger down before it arises. Quality is not inspected at the end. It is assured within the process.

The other line raised the standing of the finished-product test itself. It was not discarded. What had been an occasional quality check became a measure of whether the assembled system of control actually works. To say that the process is controlled is not enough; the result must show in the product. The test did not replace prevention. It became the evidence that prevention is working.

These two lines together form the frame of modern food hygiene, and its representative system is HACCP.

The idea of HACCP

HACCP — Hazard Analysis and Critical Control Point — was born in the United States in the 1960s. Its purpose was to assure the safety of food for astronauts. Food poisoning in space would be fatal. So what was asked for was not a test after the fact, but prevention at every step.

The frame is set out as seven principles. First, find where in the process a hazard (pericolo) lies, and of what kind. Second, fix as a critical control point the place where that hazard can be held down to an acceptable level. Third — and this is the crux — set a critical limit at each such point. Then monitor, decide the correction for a reading out of limit, verify that the system works, and keep the record.

A critical control point is not a step, but a moment within a step. Not pasteurization entire, but the one point inside it — at what temperature, held for how long. So a critical control point always comes paired with a number.

And a critical control point without a critical limit cannot exist. The critical limit is the value that divides the acceptable from the unacceptable. Without it fixed, monitoring cannot tell that a reading has gone out. To monitor is nothing other than to compare against the limit.

Risk is how likely a hazard is to occur, and the points of high risk are the ones to hold hardest.

Hazards divide broadly into three.

Beyond these three, the state of the food itself can also be a hazard — a storage temperature that falls short, for one. The temperature of the display case, met in Chapter 7, is a matter of good eating and a critical control point at once.

In Japan, hygiene management along the lines of HACCP has in recent years been required of food businesses as a rule. The legal frame behind that requirement belongs to Chapter 14.

Contamination comes from upstream

The iron rule of hygiene is this: a clean product cannot be made from a contaminated raw material. No effort downstream recovers the microbiological safety of gelato once the material upstream is dirty. The choice of the material, its storage, and its handling are the ground of everything.

Milk and the dairy products above all are a fine culture medium for pathogens. Keep the cold chain unbroken for milk and cream, and use them without delay. Cream concentrates bacteria readily — the fat globules sweep them up as they rise. Milk powder too is contaminated if it is badly kept. The pasteurization of Chapter 6 is the decisive step against these organisms, and it too has a limit. Sound materials and clean handling are its premise.

The measure here is the total bacterial count. The count takes in harmless organisms as well as pathogens. But a high value is itself a sign of poor hygiene, and speaks of a high risk that pathogens are present. To hold the count low is an indirect assurance of safety.

Keeping the workshop clean

Before any step is controlled, the workshop itself must be clean. Daily washing and disinfection (sanificazione), the handling of utensils, and the hygiene of the people. Do not mistake the order — the heaviest of the three is the last.

The literature counts four roads by which microorganisms enter: raw materials, utensils and equipment, the environment and the workers, and storage and sale. This book took the raw materials first, as the ground. Do not copy the weighting from that order. What the literature names as the most dangerous source of microorganisms is neither the material nor the utensil — it is people. That is why handwashing stands as the first rule of hygiene in the workshop.

The raw material is the door through which contamination enters unnoticed. People are the party that brings contamination in most often. The first is answered by choosing; the second, only by habit. The more people stand in the workshop, the heavier the second weighs.

And cleanliness is not made by cleaning alone. The design covers how the workshop is laid out, in what order the work runs, and where the hands are washed. That design is itself a part of hygiene. The standards for the premises, and the paths through them, are the business of Chapter 17.

• Break the eggs in a separate place. The outside of the shell is a source of contamination, so keep the breaking apart from where product is worked. Where no dedicated place is possible, share one only during hours when no other work is done. Disinfect the hands afterward (Chapters 10 and 17).
• Keep powdered materials cool, dark, and dry, and handle them with a dry utensil. Scooping powder is the one occasion on which a dry utensil is wanted.
• A utensil in use is not to be dried, but kept in moving water. Whisks, spatulas, and dishers belong in running water, or in water with disinfectant added. What is to be avoided is not wetness but stagnation. Do not set utensils in a sink of dirty water, and change the washing water constantly.
• Water alone does not clean. Hands, sponges, work clothes, utensils — none of them lose their soil without detergent. Water cannot even wet a surface properly, let alone lift what is on it.
• Record the temperature of the refrigerators and freezers, and do not overpack them — temperature control is hygiene itself (Chapter 7).

Contamination enters downstream too

The fourth road — storage and sale — is worth a section of its own. What happens here is not that contamination carried from upstream survives. It is that new contamination enters. The literature calls this recontamination.

The starting point is one sentence that changes the posture. Cold does not kill bacteria. Cold only slows their growth, and slowing is not sterilizing. Some organisms even prefer temperatures near 0 °C. Inside a frozen product biological activity all but stops, and that does not mean the product has become safe.

At the stage of the mix, that word "only" turns into the danger itself. The figures the literature gives are vivid. A mix at 20 °C, if it is 5 liters, reaches +2 °C in a few hours. At 50 liters it takes a full 24 hours. For those 24 hours the mix sits in the band where bacteria multiply fastest. When Chapter 6 said not to cool in the refrigerator but to cool fast, this was the point.

And the moment of sale is where recontamination most easily occurs.

• Do not leave the disher standing in stagnant water. Return it to a vessel of running water as soon as it is used. Left in water clouded with melted gelato, it becomes a culture medium — a microbiological test would find enormous numbers, coliforms among them.
• If a spatula is to stand in the gelato, choose one with a long handle. The handle must be long enough that it never touches the product.
• Do not touch utensils with hands that have handled money. Dishers, spatulas, cups — and cones and wafers above all, which the hand touches directly and which then go into the mouth.
• Do not leave the door of the storage cabinet open. Contamination enters through the air.
• Carry the product in vessels that have been washed and disinfected, and cover them once filled. To take every care through the whole process and then be contaminated in transit is a poor bargain.

However well the upstream is ordered, what enters downstream is not thereby stopped. So "contamination comes from upstream" is only half right.

The record is the proof

The heart of self-management is the record. Record the temperature and time of pasteurization, and the temperature of the refrigerators. Record the lot and the date of receipt of each material, and the cleaning done. Only when these are kept daily can it be proved that the gelato was made safely. The traceability of Chapter 10 serves the reproduction of taste, and it serves exactly this proof of safety.

Quality control is not a special day set aside for testing. It is running the daily process as it was decided, and writing it down as it runs. That plain repetition is what builds a workshop where accidents do not happen.

Chapter 13, next, takes up the flaws that appear all the same — the defects of gelato. It is the craft of tracing them from symptom back to cause.