Chemical and physical contamination

Outcome. FI: Henkilö tietää miten elintarvike voi saastua kemiallisesti tai fysikaalisesti. EN: The person knows how food can be contaminated chemically or physically.

Why it matters

Not every food hazard is a microbe. Cleaning agent in a sauce, glass from a broken bulb, a trace of gluten or raw kidney beans can all harm a customer.

What to know

Hazards in food can be microbiological, chemical or physical. A risk is the possibility or probability that a hazard causes the harmful effect. The operator must ensure that food is chemically, physically and microbiologically such that it endangers no one's health.

Chemical hazards. Beans contain a toxic lectin that is destroyed only by proper heat treatment; raw beans have about a hundred times more than well-cooked ones. Dried beans must be soaked, rinsed and boiled long enough, and soaking alone is not enough. Green or sprouted potatoes contain glycoalkaloids (solanine) and should not be used as food, boiling does not make them safe, and potatoes are stored protected from light. Levels are highest in new potatoes, small tubers and green ones, and peeling reduces them by about 60 percent. Mycotoxins from mould are not destroyed by heating; aflatoxin is the most toxic and causes cancer, especially in nuts and almonds. Jam with mould on the surface must not be eaten after scraping, because the toxins may have spread. Cleaning agents and disinfectants on food-contact surfaces must be water-soluble and leave no residue. Hazardous and inedible substances, including animal feed, are labelled and kept in separate secure containers. Non-food products are stored so that smell or taste cannot transfer to food.

Allergens. The EU list has fourteen allergen groups, including milk, eggs, fish, crustaceans, peanuts, soy, gluten cereals, tree nuts, celery, mustard, sesame, sulphites, lupin and molluscs. Equipment that has held an allergenic food must be cleaned and checked, at least for visible debris of the allergen, before other food. Gluten-containing raw materials are stored well labelled and protected, for example in closed packages. Gluten can reach a gluten-free product through flour dust, a shared knife or board, or bread stored close together. Allergen information for non-prepacked food is mandatory and may be given in writing or orally, if this is clearly stated near the foods. In prepacked food allergens are emphasised in the ingredient list, for example in bold. Missing allergen declarations are a hazard that the own-check must address.

Physical hazards. Glass, metal, hair and jewellery parts are foreign bodies. Lights above unprotected food need covers. Worn and scratched cutting boards collect dirt, so replace or resurface them. Wooden boards suit dry food such as bread better than perishable unpackaged food. Raw and cooked meat are always cut on different boards. Packaging materials must not be a source of contamination, and are kept on clean supports, not directly on the floor.

Scenario

A restaurant stores an open bag of wheat flour next to gluten-free flour on an open shelf. Flour dust settles on the gluten-free flour and a customer with coeliac disease reacts. Closed, labelled containers would have prevented this.

Numbers to remember

ItemValue
Allergen groups on the EU list14
Raw beans vs well-cookedabout 100 times more lectin
Peeling potatoesreduces glycoalkaloids about 60 percent

Myth vs reality

  • Myth: Soaking beans overnight makes them safe. Reality: Only proper heat treatment destroys the lectin.
  • Myth: Gluten-free flour can share an open shelf with ordinary flour. Reality: Store both protected and labelled.
  • Myth: Packaging can lie on the floor because it is not food. Reality: It must be kept on clean supports.

In the test

Allergen questions are about habits: closed labelled storage, separate tools, clean equipment. Statements that say a rinse or a small residue is fine are false.

What "easily perishable" means

Outcome. FI: Henkilö tietää mitä tarkoitetaan helposti pilaantuvilla elintarvikkeilla. EN: The person knows what is meant by easily perishable foods.

Why it matters

The hygiene passport is required for work with unpackaged easily perishable food. Storage temperatures and date marks also depend on whether a food is perishable.

What to know

An easily perishable food (helposti pilaantuva elintarvike) gives microbes good conditions to multiply because of its properties, so it must be stored at a temperature other than room temperature. It does not mean the food spoils within a day. Meat, fish, milk products and cut vegetables are examples. Pasteurised milk is easily perishable: pasteurisation kills most disease-causing microbes and extends shelf life, but the milk still spoils if not kept cold. Perishable milk and cream are stored at max +6 °C. Sprouts and cut vegetables are stored at max +6 °C too. A cut, peeled or grated vegetable is perishable, but trimming outer leaves or portioning large root vegetables for sale is ordinary trade preparation. Rice pies, meat pies and pasties with nothing added after heating are heat-made perishable bakery products. Dried foods, canned foods and UHT products before opening are not easily perishable. Frozen foods and ice cream are stored at -18 °C or colder.

"Use by" (viimeinen käyttöajankohta) is for microbiologically highly perishable foods that may endanger health after a short time, such as packed minced meat and fresh fish. After it the food is deemed unsafe and may not be sold or used. "Best before" (parasta ennen) indicates quality; the product may still be sold after it if the quality is good. It is given as day and month if the shelf life is under three months, month and year for three to eighteen months, and year for over eighteen months. The package date refers to the unopened food stored at the required temperature; after opening or slicing the operator determines the selling time.

Scenario

A deli slices ham, cuts melon and grates carrots. All three are easily perishable, so they are kept at max +6 °C, and staff who handle them unpackaged fall under the passport rule.

Numbers to remember

ItemValue
Perishable milk, cream, sprouts, cut vegetablesmax +6 °C
Frozen food, ice cream-18 °C or colder
Best before, day and monthshelf life under 3 months
Best before, month and year3 to 18 months
Best before, yearover 18 months

Myth vs reality

  • Myth: Pasteurised milk is not perishable. Reality: It stays easily perishable and must be kept cold.
  • Myth: A use-by food can be sold if it looks fine. Reality: After the date it may not be sold or used.
  • Myth: Trimming a cabbage makes it perishable. Reality: Only cutting, peeling or grating does.

In the test

Use-by is safety and best-before is quality. Any statement that allows sale of food after its use-by date is false.

Sample Quiz Questions

1. Packaging materials for food may be kept directly on the floor.

2. Pasteurised milk is an easily perishable food.

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