Chieu xa thuc pham la qua trinh chieu buc xa ion hoa len thuc pham nham tieu diet cac sinh vat con ton du trong thuc pham, nho đo bao quan thuc pham, lam giam nguy co benh tat do thuc pham gay ra, ngan chan su lay lan cua cac loai xam hai, va lam cham tre hoac loai bo moc mam hoac chin, hong .
Cac buc xa ion hoa co the đuoc phat ra boi nguon bang chat phong xa hoac tao ra bang đien. Chieu xa noi chung con đuoc dung trong khu trung dung cu y te va tuong tu . Cac dung cu hay thuc pham chieu xa khong tro thanh the co tinh phong xa, khong gay nguy hiem ve phong xa cho nguoi dung .
Thuc pham đa chieu xa can đuoc thong bao bang dau hieu Radura quoc te, hoac tai Hoa Ky la dau do Cuc quan ly Thuc pham va Duoc pham Hoa Ky (FDA) quy đinh. Đo la do nhan thuc cua nguoi tieu dung ve thuc pham xu ly bang chieu xa la tieu cuc nhieu hon nhung xu ly bang cac phuong tien khac , va su chap nhan ve phap ly tai cac nuoc khac nhau con khac nhau. Cac nghien cuu chung thi cho ra ket qua la thuc pham chieu xa la an toan, khong đoc hai, luong chat đoc sinh ra cuc thap, va an toan hon han cac xu ly bang hoa chat.


Nguyen ly tac đong Khi tac đong len thuc pham, tac nhan vat ly nhu nhiet, song đien tu (vi ba, tia X) va phong xa, se lam đut mot so lien ket mong manh trong cac phan tu huu co, gay bien tinh phan tu. No dan đen phan tu giam hoac mat kha nang tham gia qua trinh song. Neu so luong phan tu đu nhieu thi te bao ton thuong hoac chet, đac biet la ton thuong o phan tu DNA.
Qua trinh xao nau bang nhiet lam khoi thuc pham đa nau chin la bien tinh va chet toan bo. O muc tac đong thap hon, khi dung lieu chieu thich hop (la tich cua cuong đo va thoi gian chieu) nhu trong lo vi song hay trong buong chieu xa, sao cho chi lam bien tinh mot luong phan tu nhat đinh va trai đeu o moi te bao trong khoi thuc pham, thi cac te bao nay hoac chet, hoac ton thuong va trao đoi chat cham lai. Cac vi sinh vat va tac nhan gay benh bi tieu diet hoac thui chot. Nho đo thuc pham giu đuoc trang thai dinh duong lau hon, khi đo bien đoi mo gay ra chu yeu boi nhung men đa sinh ra truoc khi chieu.
Do nhu cau tieu diet ca cac tac nhan gay benh, nen chieu xa thuc pham su dung tia phong xa, va đoi khi moi dung tia X.
Qua trinh chieu xa khong tao ra them cac đong vi phong xa trong thuc pham, nen khong gay nguy hiem ve phong xa cho nguoi dung .


Ung dung Chieu xa đuoc su dung đe giam hoac loai bo cac nguy co benh do thuc pham sinh ra. Tuy thuoc vao lieu luong, mot so hoac tat ca cac mam benh sinh vat, vi sinh vat, vi khuan, virus co trong thuc pham se bi pha huy hoac tro nen khong co kha nang sinh san. Mot so thuc pham đuoc chieu xa voi lieu đu đe đam bao rang chung đuoc khu trung va khong them bat ky su hu hong hay gay benh vi sinh vat vao san pham cuoi cung .
Chieu xa cung đuoc su dung lam giam ton that sau thu hoach. Ben canh viec lam giam cac tac nhan gay benh, thi chieu xa cung tac đong toi cac te bao, lam cham toc đo tac đong cua cac enzym von đuoc san sinh ra trong qua trinh tu nhien va la tac nhan co the lam thay đoi thuc pham, va do đo lam cham qua trinh hu hong, chin, hay moc mam cua thuc pham .


Nhan thuc cong chung Nhan thuc noi chung cua nguoi tieu dung ve thuc pham xu ly bang chieu xa la tieu cuc , hinh thanh do tam ly lo ngai ve tan du phong xa sau chieu, dau rang noi chung đa khang đinh "thuc pham chieu xa rat an toan" .
Tren the gioi hien co hon 60 quoc gia chinh thuc chap nhan chieu xa thuc pham, voi khoang 500.000 tan luong thuc đuoc xu ly moi nam tren toan the gioi. Cac quoc gia khac nhau cung co nhung quy đinh khac nhau ve loai thuc pham đuoc phep chieu xa, va muc đo chieu. Tai Ao, Đuc va nhieu nuoc khac cua Lien minh chau Au chi say kho cac loai thao moc, gia vi, va gia vi co the đuoc xu ly bang chieu xa va chi voi lieu cu the. Trong khi đo tai Brazil tat ca cac loai thuc pham đuoc cho phep chieu xa o bat ky lieu nao .


Chieu xa tai Viet Nam Tai Viet Nam phap luat hien khong đat van đe chinh thuc cong nhan hay phan đoi chieu xa thuc pham. Cac chieu xa đa đuoc thu nghiem tu lau, đuoc coi nhu mot tien bo ky thuat, tuy nhien khong đuoc đua vao ung dung đai tra vi nhu cau noi đia gan nhu chua co. Nhung nam gan đay co so chieu xa ra đoi, phuc vu xuat khau hoa qua la chinh .
Cuc An toan buc xa va hat nhan thuoc Bo Khoa hoc va Cong nghe la co quan chuyen trach ve quan ly an toan phong xa, thuc hien kiem soat va tu van ve an toan . Tu nam 2003 Bo KH&CN ban hanh cac tieu chuan, tu yeu cau chung đen cac quy pham cu the.

Tieu chuan Viet Nam TCVN 7247:2003 ve thuc pham chieu xa - Yeu cau chung .
Tieu chuan Viet Nam TCVN 7509:2005 ve qui pham thuc hanh chieu xa tot đe diet con trung trong cac loai hat ngu coc .
...
Quy trinh chieu, cac đanh gia an toan, ke ca cap giay chung nhan đa chieu xa, đuoc van dung theo noi cung cap thiet bi chieu, nguon chieu, hoac theo yeu cau cua noi nhap khau hang hoa.


Chi dan Tham khao Xem them World Health Organization publications:
Food irradiation – A technique for preserving and improving the safety of Food, WHO, Geneva, 1991 (revised)
Wholesomeness of irradiated food, WHO, Geneva, Technical Report Series No. 659, 1981
Safety and nutritional adequacy of irradiated food, WHO, Geneva, 1994
High-dose irradiation: Wholesomeness of food irradiated with doses above 10 kGy, WHO, Geneva, 1999, Technical Report Series No. 890
Facts about Food Irradiation, A series of Fact Sheets from the International Consultative Group on Food Irradiation (ICGFI), 1999, IAEA, Vienna, Austria
Diehl, J.F., Safety of irradiated foods, Marcel Dekker, N.Y., 1995 (2. ed.)
Satin, M., Food irradiation, Technomic, Lancaster, 1996 (2. ed.)
Urbain, W.M., Food irradiation, Academic Press, Orlando, 1986
Molins, R. (ed.), Food irradiation – Principles and applications, Wiley Interscience, N.Y., 2001
Sommers, C.H. and Fan, X. (eds.), Food Irradiation Research and Technology, Blackwell Publishing, Ames, IA, 2006
Hauter, W. and Worth, M., Zapped! Irradiation and the Death of Food, Food & Water Watch Press, Washington, DC, 2008. Luu tru ngay 6 thang 8 nam 2010 tai Library of Congress Web Archives
The Food That Would Last Forever: Understanding the Dangers of Food Irradiation, by Gary Gibbs, Garden City Park, N.Y.: Avery Pub. Group, c1993
anon., Food Irradiation: Available Research Indicates That Benefits Outweigh Risks, RCED-00-217, ngay 24 thang 8 nam 2000, Government Accountability Office, United States General Accounting Office, Resources, Community, and Economic Development Division, Washington, D.C. 20548 "Food Irradiation" Luu tru ngay 20 thang 10 nam 2010 tai Wayback Machine
Farkas, J. and Mohacsi-Farkas, C., History and future of food irradiation, Food Sci. Technol. 22(2011),121-128
WHO Statement on 2-Dodecylcyclobutanone and Related Compounds, 2003
Evaluation of the Significance of 2-Dodecylcyclobutanone and other Alkylcyclobutanones


Lien ket ngoai Codex Alimentarius
Codex Alimentarius General Standard for Irradiated Foods (CAC/STAN 106-1983, rev.1 2003)
Codex Alimentarius Recommended International Code of Practice Code for Radiation Processing of Foods (CAC/RCP 19-1979, rev.2 – 2003)
General Standard for the Labelling of Prepacked Foods (CODEX STAN 1-1985) Luu tru ngay 6 thang 4 nam 2011 tai Wayback Machine
Food Irradiation Processing Alliance Luu tru ngay 28 thang 2 nam 2014 tai Wayback Machine FIPA represents the irradiation service industry, manufacturers of food irradiators and suppliers of cobalt-60 sources.
Food & Water Watch – food irradiation page
U.S. Food Irradiation FAQ, Food and Water Watch
Remarks by Mark Worth, Public Citizen, to the FDA, ngay 12 thang 1 nam 2005
Irradiation of Food and Food Packaging, Center for Food Safety and Applied Nutrition (US Government)
Irradiation Fact Sheet, Center for Food Safety (US non-profit organisation)
Facts about Food Irradiation, a series of 14 fact sheets, International Consultative Group on Food Irradiation, International Atomic Energy Agency, Vienna, 1991 (tieng Anh)
Bibliography on Food Irradiation, Federal Research Centre for Nutrition and Food, Karlsruhe, Germany (tieng Anh)
Should we irradiate fruit and vegetables? Dateline NBC investigation
Irradiation FAQ provided by BENEBION of Mexico (tieng Anh)
anon. What's wrong with food irradiation, revised February 2001, Organic Consumers Association, US Luu tru ngay 6 thang 5 nam 2008 tai Wayback Machine
Comment by Dr. Henry Delincee on an affidavit misrepresenting the conclusions of his studies on unique radiolytical byproducts
The Basics on the Foodfight Over Irradiation | health.usnews.com