Food Biochemistry and Food Processing (2 edition)

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BLBS102-c42 BLBS102-Simpson March 21, 2012 14:27 Trim: 276mm X 219mm Printer Name: Yet to Come


42 Food Allergens 809

black walnut, cashew, macadamia and pistachio), but clinical
studies are lacking.
While the number of reports of sesame allergy has steadily
increased, it is still not clear whether this increase is in the num-
ber of reactions or an increased rate of detection and reporting
of these allergic reactions (Stoppler and Marks 2005).

Mustard Seed Allergy

The mustard plant belongs to the familyBrassicaceaewith cab-
bage, cauliflower, broccoli, Brussel sprout, turnip and radish
(Monreal et al. 1992). Mustard is often consumed as a condi-
ment prepared from the mustard seed. The powder is made from
a mixture of two species,Sinapis albaL. (yellow mustard) and
Brassica junceaL. (oriental mustard). The varietiesBrassica
nigraandBrassica junceaare used for food products. In addi-
tion to mustard powder, mustard is also usually found in salad
dressing, mayonnaise, soups and sauces (Ensminger et al. 1983).
Mustard allergy is now considered to be a very common food
allergy, accounting for about 1.1% of food allergies in children
(Morisset et al. 2003b) and ranks fourth in children’s food al-
lergies after eggs, peanuts and cow’s milk (Rance et al. 2000).
The major allergen of yellow mustard is Sin a 1, which has been
found to be resistant to heating and proteolysis (Dominguez et al.
1990, Gonzalez de la Pena et al. 1996, Rance et al. 2000). Bra j 1
is the major allergen in oriental mustard with a structure similar
to that of Sin a 1 (Gonzalez de la Pena et al. 1991, Caballero
et al. 1994).
Mustard allergy can cause a wide array of symptoms. Rance
et al. (2000) reported that allergic reactions to mustard start
early in life and are probably linked to early consumption of
baby foods. Mustard-allergic patients will react to any food
that comes from the mustard plant, including jars of mustard,
mustard powder, mustard leaves, seeds and flowers, sprouted
mustard seeds, mustard oil and foods that contain these (Bock
2008).
Common symptoms of mustard allergy include difficulty in
breathing, shortness of breath and other breathing complications,
a rash or hives, itchy skin or general skin irritation. In some se-
vere cases, it can lead to anaphylaxis, and if left untreated, ana-
phylaxis can lead to anaphylactic shock and even death. Some
of the common symptoms of anaphylaxis include constriction of
airways in the throat and lungs, anaphylactic shock, severe drop
in blood pressure, heightened pulse and heavy heartbeat, dizzi-
ness, nausea and abdominal pain, confusion and disorientation,
and loss of consciousness. Panconesi et al. (1980) reported the
first case of mustard-induced anaphylaxis after the subject had
consumed pizza.
Incidents of cross-reactions have been rarely reported. How-
ever, single cases have been described of cross-allergy to
cauliflower, broccoli, cabbage and Brazil nuts, which may be
linked to sequence homology of some proteins (Moneret-Vautrin
2006). One of the major challenges of mustard allergy is that
many foods contain mustard even when it would seem unlikely
(e.g. lunchmeat and hot dogs). Thus, careful reading of labels
on processed foods is important for mustard-allergic patients.

MINOR FOOD ALLERGENS


As previously indicated, over 170 foods are known to provoke
allergic reactions in humans (Taylor 2000). In addition to the
nine major priority allergens, other minor food allergens and/or
emerging allergens include lupin, pea, chickpea, lentil, fruits
(e.g. apple, apricot, avocado, banana, cherry, grape, kiwi, mango,
melon, peach, pear, pineapple and strawberry) and vegetables
(celery, carrot, eggplant, lettuce, potato, pumpkin and tomato).
The reader is referred to the following references for further
reading (Pereira et al. 2002, Fernandez-Rivas 2003, Fern ́ ́andez-
Rivas et al. 2008, Harish Babu et al. 2008, Towell 2009, Skypala
2009, Jappe and Vieths 2010).

MANAGEMENT OF FOOD ALLERGY


Many of the priority food allergens such as milk, eggs, nuts and
soya bean are commonly used in food processing (e.g. processed
beef, sausages, salad dressings, breads, cakes, soups and sauces)
and pharmaceutical products (e.g. casein hydrolysates as “drug”
carriers) due to their desirable properties (Monaci et al. 2006).
Extensive use of these foods as ingredients in various prod-
ucts increases the chances of their presence as hidden allergens,
particularly when they are undeclared or present as a result of
cross-contact.
As there are currently no cures for food allergy, the best man-
agement tool is the reading of food labels and avoidance of foods
containing allergens or allergen-derived ingredients. As a result,
many countries presently require the use of the common names
of priority allergens when they are used as ingredients in foods.
A major development in the last decade has been the use of
precautionary allergen labelling to warn allergic consumers of
the likely presence of allergens. Unfortunately, consumers with
food allergy have become less avoidant to products with advi-
sory labels, such as “may contain” or “shared equipment” due to
their misuse (Hefle et al. 2007). Pieretti et al. (2009) studied the
use of advisory labels in the United States and found that 17% of
20,241 manufactured foods contained advisory labels. Thus, the
unregulated use of advisory labels has become a source of con-
fusion and frustration, which could eventually pose challenges
for allergic consumers (Pieretti et al. 2009).
Recent emergence of the hygiene hypothesis (Yazdanbakhsh
et al. 2002) brings a new approach for the management of al-
lergic diseases. Several epidemiological studies have suggested
that allergic diseases are more common in industrialised nations
and urban areas compared to developing countries and rural ar-
eas. Less frequent microbial exposures in the developed world
has been regarded as an important predisposing factor for having
higher allergic population in these regions. To compensate the
inadequate exposure of microbial load, probiotics (live bacteria,
usuallyLactobacillusandBifidobacterium)are now being added
in some infant formula along with oligosaccharides (prebiotics;
Matricardi et al. 2003). The goal is to achieve the development
of regulatory T cell or balanced Th1/Th2 activity, which could
eventually prevent allergy development (Cross et al. 2001, Pri-
oult et al. 2004). Further research will be required to confirm the
purported effects.
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