By Yohanes Raditya Wardhana, M.Sc.
Faculty of Food Science and Nutrition

Recently, an inquest was filed, revolving the death of 15-year-old girl at Heathrow Airport in 2016 after consuming a certain brand of “artisan” baguettes. Without any thorough investigation, the perpetrator was revealed to be the sesame seeds sprinkled over the baguettes, causing severe anaphylactic reaction and eventually, death [1]. This case is not one of the kind. In 2014, another teenager died after suffering from cardiac arrest, leading to her death 4 days later (in which the inquest was made this year) [2]. Suspected causes of death were no other than the consumption of certain foods, which were nuts and fish.

Albeit the peculiarity, the familiar term used in this case is called Food Allergy. It is a distinct condition that can occur conceivably in every country to all range of age. Center for Disease Control and Prevention (CDC) [3] has defined a Food Allergy as a case of human body to produce immune responses to certain types of food. Once it’s consumed, allergic reaction will follow and in severe cases, recuperation seems impossible. The allergic reactions include vomiting and/or stomach cramps, shortness of breath, swelling of the tongue or skin, and acute anaphylactic shock. The trends, prevalence as well as the complex mechanism of allergic reaction in human body has been extensively studied [4,5] and all of the efforts have been deployed to mitigate, annihilate, and avoid this dreadful case.

Now let’s take another look of these incidents from the perspective of certain foods being consumed. There are eight major foods that can cause the allergy reaction, shown by Figure 1.

Figure 1. The Big-8: Foods that are causing 90 percent of of allergic reaction in US and possibly, worldwide. [6]

Food can be classified as an allergen when it reacts solely to human’s immune system to create allergic reaction as mentioned above. Allergen is a type of antigen, which is mostly a molecule of undigested protein or complex polysaccharide and is able to react with human’s immune system by molecular binding to the immunoglobulin E (IgE) antibody [7]. Under normal circumstances, these protein or polysaccharide will be completely broken down during human digestion in which do not elicit with human’s immune response later on. However, when it is partially or not digested at all, these antigens will be treated as a foreign materials by the immune system and consequently, inducing allergic reaction. The occurrence of allergen in food can be natural or artificial, depending on many factors, e.g. certain food constituents, cross-contamination ingredients during handling, and transmission vectors and routes (pollen carried out by winds, bed bug feces and chitin, etc.). When allergens are actually the food constituents itself, it will also be subjected to various changes during food manufacturing. Hence, the challenges in Food Technology field are how to reduce or remove the allergenicity in food and what food processing technologies that can be utilize to achieve that.

There are vast arrays of food processing technologies that can be applied nowadays in order to reduce the allergenicity in food products. A study by Vanga et al., (2015) has comprehensively reviewed several food processing methods available for manufacturing food products, which then, the authors classified it into two general types: Conventional Food Processing and Novel Processing [8]. Both of these methods are further categorized into thermal or non-thermal processing based on the temperature changes applied during processing steps. Thermal processing, until now, is the most utilized method due to its extensive functionalities and relatively conveniences, which is primarily used for sterilization and for improving food texture and digestibility. In terms of allergenicity, the heat applied may alter the allergen compounds conformational structure, e.g. the phenomenon of protein denaturation, ranging from unfolding to proteolysis [9]. Similarly, the changes in conformational structure of protein can also occur during non-thermal processing method, for instance during fermentation process. Briefly, fermentation is a method that involves microorganism, which can impart the texture, aroma profile, as well as the nutritional value of final food products (fermented foods). The changes in food constituents during fermentation process may also impact the allergenicity, for instance in soy-fermented products such as tofu, miso, and tempeh. The key to reduce the allergenicity in soy fermentation is the enzymatic hydrolysis that able to deteriorate and disrupt the binding properties of allergens (mainly protein) to the IgE (antibody in human that is responsible for allergic reaction), which has been confirmed by several studies [10,11]. Other novel food processing technologies, such as radiation, ultrasound treatment, and high pressure processing (HPP), have been also been utilized and the impact to the allergenicity in foods have been studied, although the obtained results are varied, depending on the types of the food (including the allergenic compounds) and the mechanism of processing technologies [12].

Ultimately, the best prevention of food allergy cases is not exclusively derived from food processing technologies alone, but also involving multidisciplinary fields of study, developments, and global social awareness. Characterization of food allergens down to the molecular level and their reactions to human immune system is a complex and laborious process to elaborate, yet, becomes the necessity and fundamentals to develop better processing technologies to produce safer food for susceptible people suffering from food allergy. And the journey of food technologies to combat food allergy is far from over but eventually, they will get there.

1.  Food Allergy Case 1
2.  Food Allergy Case 2
3.  Food Allergy description CDC
4. Versluis, A., Knulst, A. C., Kruizinga, A. G., Michelsen, A., Houben, G. F., Baumert, J. L., & van Os‐Medendorp, H. (2015). Frequency, severity and causes of unexpected allergic reactions to food: a systematic literature review. Clinical & Experimental Allergy, 45(2), 347-367.
5. Johnson, J., Malinovschi, A., Alving, K., Lidholm, J., Borres, M. P., & Nordvall, L. (2014). Ten‐year review reveals changing trends and severity of allergic reactions to nuts and other foods. Acta Paediatrica, 103(8), 862-867.
7. Poms, R. E., Klein, C. L., & Anklam, E. (2004). Methods for allergen analysis in food: a review. Food additives and contaminants, 21(1), 1-31.
8. Vanga, S. K., Singh, A., & Raghavan, V. (2017). Review of conventional and novel food processing methods on food allergens. Critical reviews in food science and nutrition, 57(10), 2077-2094.
9. Rahaman, T., Vasiljevic, T., & Ramchandran, L. (2016). Effect of processing on conformational changes of food proteins related to allergenicity. Trends in Food Science & Technology, 49, 24-34.
10. HERIAN, A. M., TAYLOR, S. L., and BUSH, R. K. (1993). Allergenic reactivity of various soybean products as determined by RAST inhibition. Journal of Food Science. 58: 385-388
11. Ogawa, A., Samoto, M., and Takahashi, K. (2000). Soybean allergens and hypoallergenic soybean products. Journal of nutritional science and vitaminology. 46: 271-279
12. Jiménez-Saiz, R., Benedé, S., Molina, E., & López-Expósito, I. (2015). Effect of processing technologies on the allergenicity of food products. Critical reviews in food science and nutrition, 55(13), 1902-1917.