Tree nuts are rich source of health-enhancing bioactive compounds
and considered as an important food in healthy diet. Almonds (Prunus
dulcis) are among the world’s most popular tree nuts belong to
Rosaceae family, a medium-sized family of flowering plants that includes 4,828
known species in 91 genera. Almonds are a high energy snack containing
50-55% fat, 90% of which is unsaturated oleic or linoleic acid. Further,
almonds contain no cholesterol or sodium and are an abundant source of
magnesium, phosphorus, and copper. They are generally consumed raw,
toasted or as an integral part of other foods.
Regular consumption of almonds has been associated with reduced
risk of chronic-degenerative diseases such as cardiovascular disease and type 2
diabetes. They are highly nutritious and rich in healthy fats,
antioxidants, vitamins and minerals. Almonds are also an excellent source
of melatonin, a hormone that helps regulate the sleeping and waking cycle and
phytoceramides, a lipid that keeps skin hydrated and plump. Almonds
are comprised: Protein (g) 6.0: (20% protein, containing adequate amounts
of all essential amino acids with the exception of methionine), Total Fat
(g) 14.2: (Saturated Fat (g) 1.1, Polyunsaturated Fat (g) 3.5 , Monounsaturated
Fat (g) 8.9), Carbohydrates (g) 6.1, Dietary Fiber (g)
3.5, Vitamin E (mg) 7.3, Calcium (mg) 76, Iron (mg)
1.1, Magnesium (mg) 77, Copper (mg) 0.3, Potassium (mg)
208, Zinc (mg) 0.9, Folate (mcg) 12, Niacin (mg)
1.0, Calories 163.
Despite their prominent economic, nutritional, and consumer value,
almonds are capable of eliciting allergic reactions in sensitive individuals.
Most of the people experience respiratory and cutaneous symptoms after eating
almonds. Several almond proteins have been recognized as allergens. Six of
them, namely: Pru du 3, Pru du 4, Pru du 5, Pru du
6, Pru du 8, Pru du 10 have been included in the WHO-IUIS list
of allergens. One particular protein in almonds, amandin, accounts for
nearly 70% of almond’s total soluble protein content, is a known allergen. It
is the major storage protein and allergen in almonds. Amandin is a member of
the cupin superfamily, namely the 11S seed storage globulin
family. Studies on the Pru du 6 isoforms, Pru du 6.01 and Pru du 6.02,
showed that the 6.01 isoform is more broadly recognized than the 6.02 isoform.
Pru du 6 polypeptides are highly resistant to heat treatment, which is one of
the most common strategies to decrease or even eliminate the allergenic
potential of foods. Due to its heat resistance, contamination of food with Pru
du 6 polypeptides presents a serious threat to sensitized patients. A
study by Florida State University also found that heat treatment potentially
alters the structure and allergenic properties of amandin but its denaturation
has only slightly effects on IgE-binding intensity in sensitive subjects. Due
to its heat resistance, contamination of food with Pru du 6 polypeptides
presents a serious threat to sensitized patients.
Regarding strategies for prevention and therapy for an almond
allergy, the main method is dietary avoidance. According to Bezerra et al
(2021), individuals sensitive to almonds should take special attention looking
at packages and labels to prevent the ingestion of almond or almond-based
products.
Sources
Bezerra M, Ribeiro M, Igrejas G. An Updated Overview of Almond
Allergens. Nutrients. 2021; 13(8):2578. https://doi.org/10.3390/nu13082578
Zhang Y., Liu C., Su M., Roux K.H., Sathe S.K. Effect of phenolics
on amandin immunoreactivity. LWT. 2018; 98: 516-523.