Substance Info: (and synonyms)

Background Info:

Malt is made most often from barley, but sometimes even from sorghum. Malting is the controlled germination of cereals, followed by the termination of this natural process by the application of heat. Further heat is then applied to ‘kiln’ the grain and produce the required flavour and colour. For malt to be made, the barley must be capable of germination.

The malting process basically involves soaking the raw grain in water for 48 hours, then spreading it out to allow it to germinate for several more days. This process is known as "steeping" and the tanks are called "steep tanks".

Biochemical changes within the kernels transform the steeped barley into what is called "green malt". After it has sprouted enough for the purpose it will be used for, usually after 4-5 days, the green malt is moved to the "kiln" where hot air is forced through the green malt, drying and roasting it so that all biochemical activity stops, and flavour develops. The "special" barley is now considered malt. The result is a mellow, slightly sweet-flavoured powder.

The maltster's task is to get the grain to develop to a certain point, and then stop the process, "locking it up" by the use of heat. The brewer will then "unlock" the process when he mashes his milled malt, and completes the conversion to sugars which will feed the yeast to produce alcohol, whilst other characteristics in the malt produce strong contributions to the quality of the final beer. During the mashing, the natural enzymes in the grain will convert these starches into sugars that can be digested by the yeast during fermentation.

Malt that has been dried at low heat is the basic ingredient for most beer, and small amounts of specialty malts are used to give added color and flavor. Specialty malts are made by drying it at higher temperatures to give it darker color and other special characteristics. Malt is also used for making whiskey, for flavouring, and some by-products of the malting process are added to flours for baking goods to boost fibre and protein. The main constituent is starch.

There is basically no difference between brewer's malt and malted milk. During Prohibition, many brewers and maltsters stayed in business by producing malt for the malteds enjoyed as kids.

This powdered Malt has many uses, including making Vinegar, brewing Beer, and distilling liquor. Malt is also a nutritious additive to many foods. Malted-milk powder and Malt Vinegar are two of the most popular Malt products.

Barley grain contains a protein that cross-reacts in celiacs with wheat gluten. Usually, celiacs are advised to avoid malt. At present there is no proof that barley malt provokes celiac symptoms, but it may be prudent to avoid malt in these patients in the absence of definitive information. If these ingredients contain gluten residues, then they should be avoided by celiac sufferers.


Adverse Reactions:


[ 1 / 6 ]

Among the cereals, wheat, rye, barley and oats, have been reported to cause protein contact dermatitis. However, in these cases neither the involvement of an immunological mechanism nor the role of specific protein(s) has been demonstrated.This study presents a case of protein contact dermatitis from corn. The patient presented with a Type I sensitization to corn, as shown by the presence of specific immunoglobulin (Ig)E and positivity to prick tests with both a flour suspension and the salt-soluble protein fraction of this cereal. The same corn preparations induced a strong urticarial reaction on scratch testing. This reaction was followed several days later by the appearance of erythema and then eczema at the site of application. When boiled, these preparations became inactive on both prick and scratch testing. (Cristaudo 2004 ref.10233 2)

Cristaudo A, Simonato B, Pasini G, De Rocco M, Curioni A, Giannattasio M. Contact urticaria and protein contact dermatitis from corn in a patient with serum IgE specific for a salt-soluble corn protein of low molecular weight. Contact Dermatitis 2004;51(2):84-7.

[ 2 / 6 ]

A 21-year-old atopic woman who developed urticaria, angioedema of the face, and wheezy dyspnea shortly after drinking beer and after eating a corn-made snack. Skin prick tests and specific IgE measurements with beer, barley, malt, wheat, corn, rye, rice, and oat flour were positive. Immunoblotting demonstrated several IgE-binding bands at 31-56 kDa in malt and barley extracts, and a major band at 38 kDa in the beer extract. This patient developed type I hypersensitivity to barley/malt and corn. Although she also showed IgE reactivity to wheat and other cereals, no symptoms were elicited upon ingestion of these cereals, probably indicating latent sensitization to them. (Figueredo 1999 ref.5516 5)

Figueredo E, Quirce S, del Amo A, Cuesta J, Arrieta I, Lahoz C, Sastre J. Beer-induced anaphylaxis: identification of allergens. Allergy 1999 Jun;54(6):630-4.

[ 3 / 6 ]

Urticaria from beer has been reported in atopic patients. In these subjects, the skin-prick test positivity to and presence of specific serum IgE for barley malt, the basic ingredient used in brewing, suggested a type I hypersensitivity to barley component. Three patients with urticaria from beer and other atopic people, some of them suffering from baker's asthma, were examined. Skin-prick tests and detection of specific IgE demonstrated that the 5-20-kDa beer protein fraction contained the allergen. Immunoblot analysis with sera of patients with urticaria from beer showed that IgE bound only the 10 -kDa protein band in beer and malt, whereas a main 16-kDa protein was revealed in barley in addition to a very faint 10-kDa band. With the serum of a patient suffering from baker's asthma no IgE binding bands were observed in beer, whereas specific IgE binding to several proteins, including a major 16-kDa component, were detected for both malt and barley. Urticaria from beer is an IgE-mediated hypersensitivity reaction induced by a protein component of approximately 10 kDa deriving from barley. This allergen does not seem to be related to the major barley 16-kDa allergen responsible for baker's asthma. Because of the severity of the allergic manifestations to beer we recommend testing atopic patients positive to malt/barley and/or who exhibit urticarial reactions after drinking beer for their sensitivity to this beverage. (Curioni 1999 ref.3278 5)

Curioni A, Santucci B, Cristaudo A, et al. Urticaria from beer: an immediate hypersensitivity reaction due to a 10-kDa protein derived from barley. Clin Exp Allergy 1999;29:407-413

[ 4 / 6 ]

Open challenges with native barley malt was performed in 42 subjects with suspected barley malt allergy. A total of 22 subjects reacted positive with symptoms of urticaria, eyelid oedema, pruritus of the skin and mucosa, rhinitis, dyspnoe, and oedema of pharynx and uvula. RAST results from 14 challenge positive patients were positive in only three cases. Beer was identified as a common cause of relatively mild allergic reactions in barley malt allergic individuals. (Neise 1996 ref.23675 2)

Neise U, Sennekamp J. Malt - A rare food allergen? Allergologie 1996;19(3):135-138

[ 5 / 6 ]

Contact urticaria from beer. A 20-year-old waitress with atopic dermatitis since childhood, seasonal rhinoconjunctivitis, and sensitizations to numerous inhalant allergens, noticed hives on her hands whenever in contact with beer at work. She denied any aggravating effect of beer on her eczema. Drinking beer caused her no complaints. Prick/scratch test was positive:
brewer's yeast + + + (prick test)
Wolters Pilsener +++ (scratch test)
Koenig Pilsener +++ (scratch test)
Duckstein +++ (scratch test)

Total-IgE: 1975 kU/I
RAST class
wheat pollen 2.9
barley pollen 3.5
hops pollen 0
maize pollen 2.3
oat pollen 2.3
hops 0
brewer's yeast 1.2
malt 3.4
Candida albicans 1.9
Budweiser 3.1

"The contact urticaria from beer, was probably caused by an immediate-type reaction to malt (RAST class 3.4) and to brewer's yeast". (RAST class 1.2). (Gutgesell 1995 ref.1879 5)

Gutgesell C, Fuchs T. Contact urticaria from beer. Contact Dermatitis 1995;33(6):436-437

[ 6 / 6 ]

A 19-year-old patient with recurrent Quincke edema with systemic symptoms. Based on observations of the course, diary entries and specific skin tests, sensitization to malt extract from germinated barley was diagnosed. The allergic reactions usually occurred after consumption of malt-containing chocolate drinks and malt-containing snack products. Serum specific IgE for malt extract was detected. (Wuthrich 1984 ref.1859 2)

Wüthrich B. Acute recurring Quincke edema in allergy to malt extract. [German] Schweiz Med Wochenschr 1984;114(8):269-271

Occupational reactions

[ 1 ]

A report for the first time of a case of occupational asthma (OA) to malt and a case of allergic alveolitis (AA) in a 40-year-old man who was initially referred for possible OA. He noted increasing dyspnoea and a productive cough that were worse on working days and towards the end of the working week. A second 40-year-old man was also seen, who developed conjunctivitis symptoms, dyspnoea and a dry cough when unloading malt from ships. Subject 1: Skin prick tests (SPT) for common allergens and cereals (including barley) were negative whereas malt induced a 3 mm induration. After exposure to malt for 20 min, he showed a biphasic reaction with a FEV1 drop of 39% after 2 h. Subject 2: Skin prick test to cereals and malt were negative. Exposure to malt dust for 30 min resulted in no significant changes during the day. Oral temperature rose from 35.4° in the morning to 36.8° at the end of the day. The following day, after being exposed to malt for 30 min, he developed nasal congestion, cough and phlegm. Forced expiratory volume in 1 s did not change significantly. The next day he was exposed for 120 min to malt dust when he developed nasal congestion, cough, chest tightness, shivering and hyperthermia (oral temperature of 38.5°), leucocytosis (15 800 cells/mm2) with neutrophilia (93%), a drop in vital capacity of 13%. (Miedinger 2009 ref.23732 5)

Miedinger D, Malo JL, Cartier A, Labrecque M. Malt can cause both occupational asthma and allergic alveolitis. Allergy 2009 Aug;64(8):1228-1229

[ 2 ]

Contact dermatitis on the fingers of both hands, spreading to trunk and limbs, in a 54 year old maltworker from handling barley malt residues. This was followed by the onset of dyspnoea. He could drink beer without any symptoms occuring. (Pereira 1998 ref.5566 9)

Pereira F, Rafael M, Lacerda MH. Contact dermatitis from barley. Contact Dermatitis 1998;39(5):261-2

[ 3 ]

Exogenous allergic alveolitis: 22 year follow-up of malt worker's lung. (Thomas 1995 ref.12872 7)

Thomas H. Exogenous allergic alveolitis: 22 year follow-up of malt worker's lung. [German] Pneumologie 1995 Jan;49(1):32-4.

Information supplied from an abridged section of:
Allergy Advisor - Zing Solutions

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Allergy Advisor  - Food Additive and Preservative Allergy and Intolerance Database