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Impact of Processing on Food Allergens

  • Susan L. Hefle
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 459)

Abstract

In general, allergenic foods are resistant to processes commonly used in food manufacturing. Nearly all the causative proteins (allergens) retain their allergenicity after treatment by heat and/or proteolysis. Notable exceptions exist; for example, the allergenicity of many fresh fruits and vegetables is decreased or removed by relatively mild processes such as gentle heating or mashing. The use of proteolytic enzymes to remove allergenicity is successfully used in the production of hypoallergenic infant formulas, but this approach with other allergenic foods has resulted in only limited success. Processing effects can result in decreased or complete removal of allergenic qualities of a food, such as the removal of proteins in oilseed processing, which renders the oils hypoallergenic and safe for consumption by allergic individuals. This discussion will address the different allergenic foods and processes which can affect or decrease their allergenicity.

Keywords

Atopic Dermatitis Food Allergy Food Allergen Kiwi Fruit Peanut Allergen 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Aas, K. Studies of hypersensitivity to fish. Int. Arch. Allergy 1966, 29, 346–363.CrossRefGoogle Scholar
  2. Aas, K. What makes an allergen an allergen. Allergy 1978, 33, 3–14.CrossRefGoogle Scholar
  3. Aas, K. Antigens in food. Nutr. Rev. 1984, 42, 85–91.CrossRefGoogle Scholar
  4. Aas, K.; Elsayed, S. M.; Characterization of a major alleren (cod): Effect of enzymic hydrolysis on the allergenic activity. J. Allergy 1969, 44, 333–343.CrossRefGoogle Scholar
  5. Anderson, L. B. Jr.; Dreyfuss, E. M.; Logan, J.; Johnston, D. E.; Glaser, J.. Melon and banana sensitivity coincident with ragweed pollenosis. J. Allergy 1970, 45, 310–319.CrossRefGoogle Scholar
  6. Anet, J.; Back, J. F.; Baker, R. S.; Barnett, D.; Burley, R. W.; Howden, M. E. H. Allergens in the white and yolk of hen’s egg. A study of the IgE binding by egg proteins. Int. Arch. Allergy App. Immunol. 1985, 77, 364–371.CrossRefGoogle Scholar
  7. Asselin, J.; Hebert, J.; Amiot, J. Effects of in vitro proteolysis on the allergenicity of major whey proteins. J. Food Science 1989, 54, 1037–1039.CrossRefGoogle Scholar
  8. Astwood, J.D.; Leach, J. N.; Fuchs, R. L. Stability of food allergens to digestion in vitro. Nature Biotech. 1996, 14, 1269–1273.CrossRefGoogle Scholar
  9. Bahna, S. L.; M. D. Gandhi, M.D. Milk hypersensitivity. I. Pathogenesis and symptomatology. Ann. Allergy 1983, 50, 218–223.Google Scholar
  10. Baldo, B.A. Milk allergies. Aust. J. Dairy Technol. 1984, 39, 120–128Google Scholar
  11. Barnett, D.; M. E. H. Howden, M. E. H. Partial characterization of an allergenic glycoprotein from peanut (Arachis hypogaea L.). Biochim. Biophys. Acta 1986, 882, 97–105.CrossRefGoogle Scholar
  12. Barnett, D.; Baldo, B. A.; Howden, M. E. H. Multiplicity of allergens in peanuts. J. Allergy Clin. Immunol. 1983, 72,61–68.CrossRefGoogle Scholar
  13. Barrett, K. E.; Metcalfe, D. D. Immunologic mechanisms in food allergy. In Food Allergy, ed. Chiaramonte, L. T.; Schneider, A. T.; Lifshitz, F. 1988, 23–43, Marcell Dekker, New York.Google Scholar
  14. Bernhisel-Broadbent, J; Strause, D; Sampson, H.A. fish hypersensitivity. II: clinical relevance of altered fish allergenicity caused by various preparation methods. J. Allergy Clin. Immunol. 1992, 90, 622–629.CrossRefGoogle Scholar
  15. Berrens, L.; Neoallergens in heated pecan nut: products of Mai Hard-type degradation? Allergy 1996, 51, 277–278.Google Scholar
  16. Binkley, K.E. Making maple syrup: hazardous avocational ingestion of raw sap in a patient with tree nut and tree pollen sensitivity. J. Allergy Clin. Immunol. 1994, 94, 267–268.CrossRefGoogle Scholar
  17. Bleumink, E.; Berrens, L. Synthetic approaches to the biological activity of b-lactoglobulin in human allergy to cow’s milk. Nature 1966, 212, 541–543.CrossRefGoogle Scholar
  18. Bleumink, E.; Young, E. Identification of the atopic allergen in cow’s milk. Int. Arch. Allergy 1968, 34, 521–543.CrossRefGoogle Scholar
  19. Bock, S. A. Natural history of food sensitivity. J. Allergy Clin. Immunol. 1982, 69, 173–177.CrossRefGoogle Scholar
  20. Bock, S. A. Prospective appraisal of complaints of adverse reaction to foods in children during the first three years of life. Pediatrics 1987, 79, 683–688.Google Scholar
  21. Bock, S. A. Oral challenge procedures. In Food Allergy; Metcalfe, D.D., Sampson, H.A., Simon, R. A., Ed.; Blackwell Scientific Publishers: Cambridge, England, 1991; pp. 81–95.Google Scholar
  22. Bock, S. A.; Atkins, F. M. Patterns of food hypersensitivity during sixteen years of double-blind, placebo-controlled food challenges. J. Pediatrics 1990, 117, 561–567.CrossRefGoogle Scholar
  23. Burks, A. W.; Mallory, S. A.; Williams, L. W.; Shirrell, M. A. Atopic dermatitis: Clinical relevance of food hypersensitivity reactions. J. Pediatrics 1988, 113, 447–451.CrossRefGoogle Scholar
  24. Burks, A. W.; Williams, L. W.; Helm, R. M.; Connaughton, C.; Cockrell, G.; O’Brien, T. Identification of a major peanut allergen, Ara h 1, in patients with atopic dermatitis and positive peanut challenges. J. Allergy Clin. Immunol. 1991a, 88, 172–179.CrossRefGoogle Scholar
  25. Burks, A. W.; Williams, L. W.; Helm, R. M.; Thresher, W.; Brooks, J. R.; Sampson, H. A.; Identification of soy protein allergens in patients with atopic dermatitis and positive soy challenges: determination of change in allergenicity after heating or enzyme digestion. In Nutritional and Toxicological Consequences of Food Processing; Friedman, M., Ed.; Plenum Press: New York, NY, 1991b, pp. 295–307.Google Scholar
  26. Burks, A. W.; Williams, L. W.; Connaughton, C.; Cockrell, G.; O’Brien, T. J.; Helm, R. M. Identification and characterization of a second major peanut allergen, Ara h II, with use of the sera of patients with atopic dermatitis and positive peanut challenge. J. Allergy Clin. Immunol. 1992a, 900, 962–969.CrossRefGoogle Scholar
  27. Burks, A.W.; Williams, L.W.; Thresher, W.; Connaughton, C.; Cockrell, G.; Helm, R.M. Allergenicity of peanut and soybean extracts altered by chemical or thermal denaturation in patients with atopic dermatitis and positive food challenges. J. Allergy Clin. Immunol. 1992b, 90, 889–897.CrossRefGoogle Scholar
  28. Bush R. K.; Taylor S. L.; Nordlee, J. A.; Busse, W. W. Soybean oil is not allergenic to soybean-sensitive individuals. J. Allergy Clin. Immunol. 1985, 76, 242–245.CrossRefGoogle Scholar
  29. Chiaramonte, L. T.; Rao, Y.A. Common food allergens. In Food Allergy; Chiaramonte, L. T., Schneider, T. A., Lifshitz, F., Ed.; Marcel Dekker: New York, NY, 1988, pp. 89–106.Google Scholar
  30. Collin-Williams, C.; Levy, L. D. Allergy to food other than milk. In Food Intolerance, Chandra, R. K.., Ed.; El-sevier, New York, NY, 1984, pp. 137–186.Google Scholar
  31. Daul C. B.; Slattery, M.; Morgan, J. E.; Lehrer, S. B. Identification of a common major Crustacea allergen. J. Allergy Clin. Immunol. 1992, 89, 194(abstract).Google Scholar
  32. Daul, C. B.; Slattery, M.; Reese, G.; Lehrer, S.B. Identification of the major brown shrimp (Penaeus aztecus) allergen (Pen a 1) as the muscle protein tropomyosin. Int. Arch. Allergy Appl. Immunol. 1994, 105, 49–52.CrossRefGoogle Scholar
  33. Dreborg, S.; Foucard, T.; Allergy to apple, carrot, and potato in children with birch pollen allergy. Allergy 1983, 38, 167–172.CrossRefGoogle Scholar
  34. Ellis, M. H.; Short, J. A.; Heiner, D. C.; Anaphylaxis after ingestion of a recently introduced hydrolyzed whey protein formula. J. Pediatrics 1991, 118, 74–77.CrossRefGoogle Scholar
  35. Elsayad, S.; Aas, K. Characterization of a major allergen (cod): observations on effect of denaturation on the allergenic activity. J. Allergy 1971, 47, 283–291.Google Scholar
  36. Elsayad, S.; Aas, K.; Sletten, K.; Johansson, S. G. O. Tryptic cleavage of a homogenous cod fish allergen and isolation of two active polypeptide fragments. Immunochemistry 1972, 9, 647–661.CrossRefGoogle Scholar
  37. Elsayed, S.; Hammer, A. S. E.; Kalvenes, M. B.; Flovagg, E.; Apold, J.; Vik, H.; Antigenic and allergenic determinants of ovalbumin. I. Peptide mapping, cleavage at the methionyl peptide bonds and enzymic hydrolysis of native and carboxymethyl OA. Int. Arch Allergy. Appl. Immunol. 1986, 79, 101–107.CrossRefGoogle Scholar
  38. Eriksson, N. E. Food sensitivity reported by patients with asthma and hay fever. Allergy 1978, 33, 189–196.CrossRefGoogle Scholar
  39. Fallier, C. J. Anaphylaxis to kiwi fruit and related “exotic” items. J. Asthma 1983, 20, 193–196.CrossRefGoogle Scholar
  40. Fine, A. J. Hypersensitivity reaction to kiwi fruit (Chinese gooseberry, Actinidia chinensis). J. Allergy Clin. Immunol. 1981, 68, 235.CrossRefGoogle Scholar
  41. Fiocchi, A.; Restani, P.; Riva, E.; Restelli, A. R.; Biasucci, G.; Galli, C. L.; Giovanni, M.; Meat allergy: II – Effects of food processing and enzymatic digestion on the allergenicity of bovine and ovine meats. J. Am. College Nutrition 1995, 14, 245–250.Google Scholar
  42. Gern, J.E.; Yang, E.; Evrard, H. M.; Sampson H. A.. Allergic reaction to milk-contaminated “nondairy” products. N. Eng. J. Med. 1991, 324, 976–979.CrossRefGoogle Scholar
  43. Goldman, A. S.; Anderson, D. W.; Sellers, W. A.; Saperstein, S.; Kniker, W. T.; Halpern, S. R. Milk allergy. I. Oral challenge with milk and isolated milk proteins in allergic children. Pediatrics 1963, 32, 425–443.Google Scholar
  44. Gu, J.; Matsuda, T.; Nakamura, R.; Antigenicity of ovomucoid remaining in boiled shelled eggs. J. Food Science 1986, 51, 1448–1450.CrossRefGoogle Scholar
  45. Halken, S.; Host, A.; Hansen, L. G.; Osterballe, O.; Safeety of a new, ultrafiltrated whey hydrolysate formula in children with cow milk allergy: a clinical investigation. Pediatric Allergy Immunol. 1993, 4, 53–59.CrossRefGoogle Scholar
  46. Hannuksela, M.; Lahti, A. Immediate reaction to fruits and vegetables. Contact Derm. 1977, 3, 79–84.CrossRefGoogle Scholar
  47. Herian, A.; Taylor, S. L.; Bush, R. K. Identification of soybean allergens by immunoblotting with sera from soy-allergic adults. Int. Arch. Allergy Appl. Immunol. 1990, 92, 192–198.CrossRefGoogle Scholar
  48. Herian, A. M.; Taylor, S. L.; Bush, R. K. Allergenic reactivity of various soybean products as determined by RAST inhibition. J. Food Science 1993, 58, 385–388.CrossRefGoogle Scholar
  49. Hoffman, D. Immunochemical identification of allergens in egg white. J. Allergy Clin. Immunol. 1983, 71, 481–486.CrossRefGoogle Scholar
  50. Hoffman, D. R.; Day, E. D.; Miller, J. S. The major heat stable allergen of shrimp. Ann. Allergy 1981, 47, 17–22.Google Scholar
  51. Hoffman, D. R.; Collins-Williams, C.; Cold-pressed peanut oils may contain peanut allergen. J. Allergy Clin. Immunol. 1994, 93, 801–802.CrossRefGoogle Scholar
  52. Honma, K.; Kohno, Y; Saito, K.; Shimojo, N.; Tsunoo, H.; Niimi, H. Specificities of IgE, IgG and IgA antibodies to ovalbumin. Int. Arch. Allergy Immunol. 1994, 103, 28–35.CrossRefGoogle Scholar
  53. Host, A.; Samuelsson, E. G. Allergic reactions to raw, pasteurized, and homogenized/pasteurized cow milk: a comparison. Allergy 1988, 43, 113–118.CrossRefGoogle Scholar
  54. Jones, R. T.; Squillace, D. L., Yunginger, J. W. Anaphylaxis in a milk-allergic child after ingestion of milk-contaminated kosher-pareve-labeled “dairy-free” dessert. Ann. Allergy 1992, 68, 223–227.Google Scholar
  55. King, T. P. Chemical and biological properties of some atopic allergens. Adv. Immunol. 1976, 23, 77–105.CrossRefGoogle Scholar
  56. King, T. P.; Hoffman, D.; Lowenstein, H.; Marsh, D.G.; Platts-Mills, T.A.; Thomas, W. Allergen nomenclature. Int. Arch. Allergy Immunol. 1994, 10, 224–227.CrossRefGoogle Scholar
  57. Kjellman, N. M. Natural history and prevention of food hypersensitivity. In Food Allergy; Metcalfe, D. D., Sampson, H. A., Simon, R. A., Ed.; Blackwell Scientific Publishers: Cambridge England, 1991, pp. 319–331.Google Scholar
  58. Kohno, Y; Honma, K.; Saito, K.; Shimojo, N.; Tsunoo, H.; Kaminogawa, S.; Niimi, H.; Preferential recognition of primary protein structures of a-casein by IgG and IgE antibodies of patients with milk allergy. Annals Allergy 1994, 73, 419–422.Google Scholar
  59. Kurisaki, J.; Konishi, Y; Kaminogawa, S.; Yamauchi, K.; Studies on the allergenic structure of hen ovomucoid by chemical and enzymic fragmentation. Agr. Biol. Chem. 1981, 45, 879–886.CrossRefGoogle Scholar
  60. Lahti, A.; Bjorksten, F.; Hannuksela, M. Allergy to birch pollen and apple, and cross-reactivity of the allergens studies with the RAST. Allergy 1980, 35, 297–300.CrossRefGoogle Scholar
  61. Langeland, T. A clinical and immunological study of allergy to hen’s egg white. III. Allergens in hen’s egg white studied by crossed radioelectrophoresis (CRIE). Allergy 1982, 37, 521–530.CrossRefGoogle Scholar
  62. Lifshitz, F. Food intolerance. In Food Allergy, Chiaramonte, L. T., Schneider, A. T., Lifshitz, F., Ed.; Marcel Dekker: New York, NY, 1988, pp. 3–21.Google Scholar
  63. Malanin, K.; Lundberg, M.; Johansson, S. G. O. Anaphylactic reaction caused by neoallergens in heated pecan nut. Allergy 1995, 50, 988–991.CrossRefGoogle Scholar
  64. Minford, A. M. B.; MacDonald, A.; Littlewood, J. M. Food intolerance and food allergy in children: a review of 68 cases. Arch. Dis.Child. 1982, 57, 742–747.CrossRefGoogle Scholar
  65. Moneret-Vautrin, D. A. Food antigens and additives. J. Allergy Clin. Immunol. 1986, 78, 1039–1045.CrossRefGoogle Scholar
  66. Moneret-Vautrin, A.; Humbert, G.; Alais, C.; Grilliat, J. P. Donnees recentes sur les propretes immunoallergologiques des proteins laitieres. Le Lait 1992, 62, 396–399.CrossRefGoogle Scholar
  67. Nordlee, J. A.; Taylor, S. L.; Jones, R. T.; Yunginger, J. W. Allergenicity of various peanut products as determined by RAST inhibition. J. Allergy Clin. Immunol. 1981, 81, 376–382.CrossRefGoogle Scholar
  68. Oei, H. D.; Tjiook, S. B.; de Haas, R.; Does the allergenicity of apple disappear after microwave treatment? J. Allergy Clin. Immunol. 1995, 95, 329 (abstract).Google Scholar
  69. Ohishi, A; Watanabe, k.; Urushibata, M.; Utsuno, K.; Ikuta, K.; Sugimoto, K.; Harada, H. Detection of soybean antigenicity and reduction by twin-screw extrusion. J. Assoc. Official Analy. Chem. 1994, 71, 1391–1396.Google Scholar
  70. Okamoto, M.; Hayashi, R.; Enomoto, A.; Kaminogawa, S.; Yamauchi, K. High-pressure proteolytic digestion of food proteins: selective elimination of b-lactoglobulin in bovine milk whey concentrate. Agric. Biol. Chem. 1991,55, 1253–1257.CrossRefGoogle Scholar
  71. Ortolani, C.; Ispano, M.; Pastorello, E.; Bigi, A.; Ansaloni, R. The oral allergy syndrome. Ann. Allergy 1988, 67, 47–52.Google Scholar
  72. Pauli, G.; Bessot, J. C.; Dietemann-Molard, A.; Braun, P. A.; Thierry, R. Celery sensitivity: clinical and immunological correlations with pollen allergy. Clin. Allergy 1985, 15, 273–279.CrossRefGoogle Scholar
  73. Pedersen H. E.; Allergenicity of soy proteins. In Vegetable Protein Utilization in Human Foods and Animal Feed-stuffs; Applewhite, T, H, Ed.; American Oil Chemists Society: Champaign, IL, 1988, p. 204–212.Google Scholar
  74. Plebani, A.; Albertini, A.; Scotta, S.; Ugazio, A.G.; IgE antibodies to hydrolysates of cow milk proteins in children with cow milk allergy. Annals Allergy 1990, 64, 279–280.Google Scholar
  75. Porras, O.; Carlsson, B.; Fallstrom, S. P.; Hanson, L. A. Detection of soy protein in soy lecithin, margarine, and, occasionally, soy oil. Int. Arch. Allergy Appl. Immunol. 1985, 78, 30–32.CrossRefGoogle Scholar
  76. Samoto, M.; Akasaka, T.; Mori, H.; Manabe, M.; Ookura, T.; Kawamura, Y. Simple and efficient procedure for removing the 34kDa allergenic soybean protein Gly m 1, from defatted soy milk. Bioscience Biotech. Biochem. 1994, 58, 2123–2125.CrossRefGoogle Scholar
  77. Sampson, H. A. Food allergy. Curr. Opinion Immunol. 1990a, 2, 542–547.CrossRefGoogle Scholar
  78. Sampson, H. A. Peanut anaphylaxis. J. Allergy Clin. Immunol. 1990b, 86, 1–3.CrossRefGoogle Scholar
  79. Sampson, H. A.; Cooke, S.K. Food allergy and the potential allergenicity-antigenicity of microparticulated egg and cow’s milk proteins. J. Am. Coll. Nutr. 1990, 9, 410–417.Google Scholar
  80. Sampson, H. A.; McCaskill, C. C. Food hypersensitivity and atopic dermatitis: evaluation of 113 patients. J. Pediatrics 1985, 1071, 669–675.CrossRefGoogle Scholar
  81. Sampson, H. A.; Metcalfe, D. D. Food allergies. J. Am. Med. Assoc. 1992, 268, 2840–2844.CrossRefGoogle Scholar
  82. Sampson, H. A.; Scanlon, S. M. Natural history of food hypersensitivity in children with atopic dermatitis. J. Pediatrics 1989, 115, 23–27.CrossRefGoogle Scholar
  83. Schreiber, R. A.; Walker, W. A. Food allergy: facts and fiction. Mayo Clinic Proc. 1989, 64, 1381–1391.Google Scholar
  84. Shibaski, M.; Suzuki, S.; Nemob, H.; Kurome, T. Allergenicity of major component protein of soybean. Int. Arch. Allergy Appl. Immunol. 1980, 61, 441–448.CrossRefGoogle Scholar
  85. Siemensma, A. D.; Weijer, W. J.; Bak, H. J. The importance of peptide lengths in hypoallergenic infant formulas. Trends Food Science Tech. 1993, 4, 16–21.CrossRefGoogle Scholar
  86. Simmons, C. T. Method of decreasing the allergenicity of psyllium seed husk. United States Patent Number 5, 273,764, 1993.Google Scholar
  87. Tanabe, S.; Arai, S.; Watanabe, M.. Modification of wheat flour with bromelain and baking hypoallergenic bread with added ingredients. Bioscience Biotech. Biochem. 1996, 60, 1269–1272.CrossRefGoogle Scholar
  88. Taylor, S. L. Food allergy. J. Food Prot. 1980, 43, 300–306.Google Scholar
  89. Taylor, S. Food allergies. Food Technol. 1985, 39, 98–105.Google Scholar
  90. Taylor, S; Lehrer; S.B. Principles and characteristics of food allergens. Crit. Rev. Food Sci. Nutr. 1996, 36(S), S91-Sl18.CrossRefGoogle Scholar
  91. Taylor, S. L.; Busse, W. W.; Sachs, M.I.; Parker, J. L.; Yunginger, J. W.. Peanut oil is not allergenic to peanut-sensitive individuals. J. Allergy Clin. Immunol. 1981, 68, 372–375.CrossRefGoogle Scholar
  92. Teuber, S.D.; Brown, R.L., Haapanen, L. A. D. S. Allergenicity of gourmet nut oils processed by different methods. J. Allergy Clin. Immunol. 1997, 99, 502–507.CrossRefGoogle Scholar
  93. Van Beresteijn, E. C. H.; Peeters, R. A.; Kaper, J.; Meijer, R. J. G. M.; Robben, A. J. P. M., Schmidt, D. G.. Molecular mass distribution, immunological properties and nutritive value of whey protein hydrolysates. J. Food Science 1994, 57, 619–625.Google Scholar
  94. Wahn, U.; Wahl, R.; Rugo, E. Comparison of the residual allergenic activity of six difference hydrolyzed protein formulas. J. Pediatrics 1992, 21, 80S-84S.CrossRefGoogle Scholar
  95. Watanabe, M.; Miyakawa, J.; Ikezawa, Z.; Suzuki, Y; Hirao, T.; Yoshizawa, T.; Arai, S. Production of hypoallergenic rice by enzymic decomposition of constituent proteins. J. Food Science 1990, 55, 781–783.CrossRefGoogle Scholar
  96. Watanabe, M.; Suzuki, Y; Ikezawa, Z.; Arai, S. Controlled enzymatic treatment of wheat proteins for production of hypoallergenic flour. Bioscience Biotech. Biochem. 1994, 58, 388–390.CrossRefGoogle Scholar
  97. Werfel, S. J.; Cooke, S. K.; Sampson, H. A.; Clinical reactivity to beef in children allergic to cow’s milk. J. Allergy Clin. Immunol 1997, 99, 293–300.CrossRefGoogle Scholar
  98. Yunginger, J. W.; Gaurerke, M. B.; Jones, R. T.; Dahlberg, M. E.; Ackerman, S. J. Use of radioimmunoassay to determine the nature, quantity, and source of allergenic contamination of sunflower butter. J. Food Prot 1983, 46, 625–629.Google Scholar
  99. Yunginger, J. W.; Sweeney, K. G.; Sturner, W. Q.; Giannandrea, L. A.; Teigland, J. D.; Bray, M.; Benson, P. A.; York, J. A.; Biedrzycki, L.; Squallace, D. L., Helm, R. M. Fatal food-induced anaphylaxis. J. Am. Med. Assoc. 1988, 260, 1450–1452.CrossRefGoogle Scholar

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© Springer Science+Business Media New York 1999

Authors and Affiliations

  • Susan L. Hefle
    • 1
  1. 1.Food Allergy Research and Resource Program, Department of Food Science and TechnologyUniversity of NebraskaLincolnUSA

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