Cheese is a milk-derived food product, obtained from raw or pasteurized, whole or semi-skimmed, milk from various species, following a variety of industrial or artisanal physico-chemical and microbiological procedures. Milk proteolysis takes place during cheese production.  Mold-type cheese involves different fungal species during the cheese ripening process. A great diversity of molds and yeasts is present at the surface and in some cases inside the mold-type cheeses. Food-related and occupational IgE sensitization to mold-type cheese has been reported.

Nature

A mixture of cheeses from cow’s milk (Camembert, brie, Gorgonzola) and ewe’s milk (Roquefort).

During cheese manufacture, the curdling (coagulation) step results in the separation of milk caseins (curd, approximately 80% of milk proteins) and milk whey (soluble) proteins [1]. The curds are used for the next steps of cheese making, which include proteolysis with breakdown of proteins into peptides [2, 3]. Various species of Penicillium are used for manufacturing mold-type cheeses, such as Penicillium camemberti (Camembert and brie cheese), Penicillium candidum (Camembert, brie and Gorgonzola cheese), or Penicillium roqueforti (Roquefort cheese). Mold-type cheese contains a genuine microbiota, both inside and at the surface of the cheese (edible rind), with a great diversity of bacteria and yeasts reported in the literature [2, 4]. Blue or green marbling of mold-type cheeses, as seen in Roquefort or Gorgonzola, denotes the growth of mold spores into hyphae. Yeast species which have been reported from mold-type cheeses include Candida spp (C. catenulate, C. famate, C. intermedia, C. kefyr, C. lipolytica among others), Rhodotorula mucilaginosa, Rhodotorula minuta, Rhodotorula glutinis, Debaryomyces hansenii, Saccharomyces cerevisiae, Saccharomyces kluyveri, Cryptococcus albidus, Geotrichum spp, Trichosporon spp, Torulaspora spp [5, 6].

Tissue 

Milk (raw or heated, processed), microbial and/or enzymatic components necessary for cheese production (such as pepsin and chymosin for mold-type cheese) [2].

Risk factors 

Milk allergy is a risk factor for cheese allergy, due to shared allergenic components [1]. Atopy is a risk factor for occupational allergy to cheese [7].

Worldwide distribution 

It is estimated that a third of the global cow’s milk production, and the major part of ewe’s and goat’s milk production, are used for making cheese [2].

Main 

The main route of exposure to cheese is ingestion. 

Secondary 

Occupational exposure in cheesemakers is an alternative route exposure.

Depending on the route of exposure, allergy to cheese may present as food or respiratory allergy.

Milk

Proteolysis of milk allergens retained following cheese coagulation, i.e. mainly casein, results in cheese displaying lower allergenicity than milk, albeit higher than baked milk [2, 8, 9]. The corresponding categorization of milk-allergic patients in three groups is relevant for better diagnostic and management stratification of milk allergic patients [8].

Mold

Molds used for cheese manufacture are saprophytic and usually not associated with human disease except in occupational settings. Hypersensitivity pneumonitis or extrinsic allergic alveolitis have been reported in patients occupationally exposed to Penicillium spp used during cheese manufacturing, such as P. roqueforti [10] or P. verrucosum [11]. Exceptionally, they may however cause infections, as reported in an immunocompetent 40-year old female who developed a typical fungus ball with Penicillium roqueforti [12].

Enzymes and dyes

Occupational rhinitis and asthma may be caused by ingredients added during cheese manufacture such as enzymes (e.g. calf chymosin) from natural or artificial rennet [7].

Food allergy to dyes used for cheese (e.g. annatto) has been reported as anaphylaxis in a 58-year old atopic patient [13].

Author: Joana Vitte

Reviewer: Dr. Christian Fischer

Last reviewed: June 2022.