Detection of Allergens from Lupines in Food

Lupines, which belong to the legume family, are closely related to peanuts, peas, lentils and soybeans. The preferred variety in Europe is the sweet blue lupine (Lupinus angustifolius), the seeds of which are known to have several beneficial effects on nutrition and physiology: they are high in proteins, fibres and minerals but low in digestible carbohydrates and calories; they are low in purines that form uric acid and inherently contain no cholesterol or gluten.

Because they are high in proteins, lupines are most frequently used to prepare dishes that are suitable for lactose-intolerant or vegetarian diets. Lupine flour is also useful for making baking products that contain no gluten and ready-to-eat products for dietary management of patients with celiac disease who are unable to tolerate the gluten that is found in grain products. Lupine protein is also suitable as a substitute for meat in vegetarian diets. Because there are no genetically-modified lupine varieties that are available commercially, lupines are often used to replace soya in order to produce GMO-free products. Today, health food stores offer a wide variety of products such as vegan burgers, tofu, quark, lactose-free ice cream and lupine coffee that appeal primarily to vegetarians.

Despite its many benefits, lupines also contain many proteins that can elicit allergic reactions. A lupine allergy may occur as an isolated allergic or as a cross-sensitivity with peanuts. Both children and adults can be affected. Symptoms such as nettle rash, difficulty breathing, abdominal pain and nausea or even anaphylactic shock may arise in response to even a tiny quantity.

Because of this distinct allergenic potential, lupines and products produced thereof are listed as allergens that are subject to labelling. Hence, they must be listed in the ingredients on the label of any food product (Directive 2006/142/EC). The allergen labelling requirements are applicable even if lupine products such as flour or protein concentrates are added in small quantities for their emulsifying properties.

The Eurofins laboratories for food and feed testing in Germany offer two methods using ELISA and PCR that will reliably detect lupine DNA and proteins in different food products and precursor food additives. 

Legal bases and guidelines

• Commission Directive 2006/142/EC

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