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Matrix list for Listeria monocytogenes and Listeria spp.

Matrix group


Types (matrix)

Example of items

Milk & Dairy

Raw milk and dairy products

Raw milks and/or fermented/acidified milks (not heat treated)

Raw milk

Raw fermented/acidified, raw milk yoghurts, raw dairy-based drinks

Raw milk-based products, with high fat content and/or high background microflora

Raw butters

Raw creams

Hard and semi-hard cheeses (e.g. Comté, Beaufort)

Blue cheeses (Roquefort)

Soft cheeses (e.g. Brie, Munster)

Heat-processed milk and dairy products

Pasteurized dairy products

Milk-based desserts, ice creams, drinks, creams

Fermented/acidified pasteurized milk, yoghurts, dairy-based products

Pasteurized milks



Hard and semi-hard cheeses (heat processed) (e.g. Comté, Emmental, Gouda)

Blue cheeses (Bleu de Bresse)

Soft cheeses (e.g. Brie, Munster)


Milk powders

Powder for milk-based desserts



Raw meat and ready-to-cook meat products (except poultry)

Fresh meats (unprocessed)

Carcasses, meat cuts, Carpaccio's

Minced meat, meat preparations, Carpaccio's

Carcasses, swabs, rinsates

Ready-to-cook (processed)

Frozen burger patties, marinated beef shish-kabobs

Ready-to-eat, ready-to-reheat meat products

Cooked meat products

Cooked ham, pâté

Fermented or dried meat products


Raw cured (smoked) (aw > 0,92)

Filet de sax, lard

Raw cured (smoked) (aw < 0,92)

Cobourg ham, dry cured ham

Raw poultry and ready-to-cook poultry products

Fresh meats (unprocessed)

Carcasses, meats, cuts

Carcasses, swabs, rinsates

Minced meat, meat preparations

Ready-to-cook products (processed)

Seasoned chicken breasts

Ready-to-eat, ready-to-reheat meat poultry products

Cooked meat products

Cooked turkey filet

Fermented or dried meat products

Chicken sausage

Raw cured (smoked) (aw > 0,92)

Smoked turkey filet


Eggs and egg products (derivates)

Eggs (unprocessed)

Shell eggs

Egg products (heat processed) with additives (salt or sugar >2%)

Egg yolk, egg white, whole liquid egg

Egg products (heat processed) without additives

Egg yolk, egg white, whole liquid egg


Egg powder

Fish & Seafoods

Raw and ready-to-cook fish and seafoods (unprocessed)

Fish (unprocessed)


Shellfish (unprocessed)

Oyster, clam, scallop, mussel

Crustaceans (unprocessed)

Shrimp, crab and crab meat, lobster

Ready-to-eat, ready-to-reheat fishery products

Cooked fishery products

Shelled and shucked products of cooked crustaceans, fish and seafood terrines

Acidified and marinated fishery products

Roll herring, anchovy

Smoked or cured, and other processed products (aw > 0,92)

Smoked fish

Smoked or cured, and other processed products (aw < 0,92)

Smoked fish, dried (salted) fish


Fresh produce and fruits

Cut ready-to eat fruits

Fruit mixes

Bagged pre-cut leafy vegetables, salads, shredded carrot

Produces grown in or in contact with the ground

Potatoes, yams, sweet potatoes, cassava, dahlia, carrots, cruciferous vegetables


Soy, fenugreek, alfalfa, mung

Raw fruit/vegetable juices (unpasteurized)

Freshly squeezed strawberry juice, smoothies, carrot juice

Leafy greens

Basil, cilantro, green onions, lettuce and parsley

Vegetables and fruits (unprocessed) not described above


Processed fruits and vegetables

Heat-processed fruit/vegetables juices

Pasteurized apple juice

Canned fruits and vegetables (ambient stable)

Canned pineapples

Heat processed vegetables and fruits

Blanched spinach, frozen vegetables blanched

Fermented/acidified vegetables

Fermented cabbage, pickle

Dried cereals, fruits, nuts, seeds and vegetables

Nuts and seeds

Nuts, nut meats, nut butters, seeds

Dried fruits and vegetables (aw <0.60)

Freeze-dried vegetables

Dried cerealas

Corn, oat, breakfast cereals


Wheat, buckwheat, oat


Chocolate, bakery products and confectionary


Chocolate, bakery products and confectionary



Bakery products with custard, confectionaries

Dry powered

Cake mixes

Multi-component foods

Multi-component foods or meal Components

Dry & sugared low moisture (aw <0.85)

Hot meals

Ready to (re)heat food: refrigerated

Cooked chilled foods, boiled rice or pasta, vol-au-vent in vacuum

Ready to (re)heat food: frozen

Frozen fries, pizza, stuffed croissants

Ready to (re)heat food: ambient stable (canned)

Vol-au-vent in glass bottles

Mayon­naisebased delisal­ads (acid) with raw ingre­dients

Raw vegetable salads with dressing

Mayon­naisebased delisal­ads (acid) with pro­cessed ingre­dients

Sandwich spreads

Ambient stable acid foods (pH < 4,8)

Ketchup, sauces, dressings, mayonnaises, mustard

Environmental samples

Environmental samples (food or feed production)

Equipment or production environment

Swabs, dusts

Waters used in manufactureing process

(Recycled) washing water, process water



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