Apples as a local superfood – also for allergy sufferers?

An Apple a Day – What makes apples so healthy

Even after more than 100 years, the well-known English proverb “An apple a day keeps the doctor away” has lost none of its relevance. On the contrary: research is helping us to understand better and better why apples are so health: 

• Dietary fiber: Apples are rich in soluble and insoluble dietary fiber such as pectin and cellulose. They ensure a longer feeling of satiety, have a prebiotic effect, i.e. they serve as food for beneficial intestinal bacteria, fill the intestines, facilitate digestion and are an integral part of any gut-healthy diet. Polyphenols: There are particularly high levels in the flesh of apples.  
  
• Polyphenols, which are secondary plant substances and act as natural antioxidants that protect our cells from oxidative stress.² The peel mainly contains anthocyanins and flavonols such as the well-known quercetin.² 
• Vitamin C: Vitamin C also acts as an antioxidant* and supports the immune system**.³ 
• Low in fat and calories: A medium-sized apple contains just under 100 calories.

EVERYONE IN GERMANY CONSUMES AROUND 20 KILOGRAMS OF APPLES PER YEAR.¹ 
THIS MAKES THE APPLE THE MOST POPULAR TYPE OF FRUIT FOR YEARS.

Why modern apple varieties no longer turn brownn

The supermarket mainly offers new, shiny apple varieties that do not turn brown as quickly and taste sweeter. The polyphenol content plays a key role. The reason for the undesirable brown coloring is the oxidation of polyphenols. This is triggered when apples come into contact with oxygen after peeling, grating or cutting. This creates intermediate substances that crosslink to form brown to black melanins .²

Breeders use two tricks to ensure that apples stay lighter for longer:  polyphenols are bred out. 

1. In apples such as Golden Delicious, Granny Smith and Fuji, the enzyme responsible for oxidation (polyphenol oxidase, PPO) has been modified through breeding.
2. Since 2017, genetically modified "Artic Apples" have also been marketed in the USA, in which the enzyme PPO has been switched off through genetic engineering.

Old varieties – the underestimated treasures

Old apple varieties have largely disappeared from conventional supermarkets. Unjustly, in our opinion:

• Old varieties often taste more intense and have a more sour, slightly bitter aroma. Each variety has an individual taste profile and a wide variety of aromas, e.g. spicy, nutty or floral.
• Old varieties represent greater genetic diversity.
• They are usually better adapted to regional conditions and therefore more robust against pests and diseases - and therefore require fewer pesticides.
• Old apple varieties contain more vitamin C on average.
• The flesh of old apple varieties usually contains significantly more polyphenols.
• Old apple varieties such as Alkmene, Goldparmäne and Red Boskoop are often much better tolerated by allergy sufferers than new varieties such as Braeburn, Golden Delicious and Granny Smith.^{2, 5, 6}

A detailed List of particularly well-tolerated, low-allergen apple varieties can be found at the German BUND Lemgo.⁷

Cross allergies – birch pollen-associated apple allergy

If in spring not only your eyes itch but your tongue also burns when you bite into an apple, it could be a cross allergy. This is caused by allergenic protein structures in pollen that are similar to proteins in certain foods.

The most common fruit allergy in Germany is the birch pollen-associated apple allergy, with around four million sufferers.² Studies show that around two thirds of the birch pollen-associated apple allergy.² Studies show that around two-thirds of people who are allergic to birch pollen also experience cross-reactions to foods such as apples, carrots or hazelnuts.⁸ The apple allergen Mal d 1 plays a central role in this, typically causing a burning sensation on the tongue or swelling of the lips. Since the allergen is sensitive to heat, acid and oxidation, those affected can noticeably improve tolerance with the right preparation.²

Polyphenols also protect against allergic reactions to a certain extent by neutralising apple allergens.²

*Notes

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