Faculty of Agricultural Engineering and Technology ,IGKV ,Raipur (CG)

Presentation On

“Food Irradiation”

Submitted To,Er.N.K.MishraAsst.prof.,dept.of APFE

Submitted By,Lalit KumarM.Tech pre.(APFE)

Contents•What is food irradiation.•Why irradiate foods.•Science of irradiation. •Radiation sources.•History of food irradiation.•What foods are currently irradiated.•Approved dosages by FDA & USDA.•How does food irradiation help.•Benefits of food irradiation.

What is food irradiation?Process in which food products are exposed to a controlled amount of radiant energy such as gamma rays or electron rays.

Why irradiate foods?•To kill pathogenic bacteria such as E.colli:0157,Campylobacter,Salmonella,Clostridium,perfrings etc.•To control insects and parasites.•To reduce spoilage.•To increase shelf life by slowing ripening of fresh fruits & vegetables.

Irradiation has received approval for use in several food categories from the United States Food & Drug Administration (FDA) and has been proven as an effective food safety measure through more than 50 years of research.Importance of Food safetyThe presence of microbial pathogens on human foods is a serious global problem.Food pathogens enter the food supply through various extrinsic sources and intrinsic routes.

Science of Irradiation More than 50 years of research has gone into our understanding of safe and effective operation of irradiation as a food safety measure more than any other technology used in the industry today.Food radiation employs controlled amounts of ionizing (having sufficient energy to create positive & negative charges) radiation to destroy bacteria ,pathogens & pets in food & agri. products , greatly reducing the threat of food borne disease.

Ionizing radiation includes gamma rays (from radioactive isotopes Co-60 or Cesium-137) ; beta rays generated by electron beam or E-beam, and X-rays.None of these irradiation sources has sufficient energy to be capable of including radioactivity; however they do have enough energy to remove electrons from atoms to form ions or free radicals.The free electrons collide with chemical bonds in the microbial DNA molecules, thereby breaking them and rendering the microbe dead.

DNA DESTRUCTION

Units of radiation

The amount of ionizing radiation absorbed dose and is measured in units of rads & grays;

1 rad = 100 erg/g1 Gy = 100 rads

With 1 Gy equal to 1 joule/kg and 1000 grays equal to 1 kilo Gray (kGy)

Approved Dosages by FDA & USDA

Not to exceed 1 kGy-To control insects,arthropods & to inhibit maturation of fresh foods.Not to exceed 3 kGy-PoultryNot to exceed 4.5 kGy-Refrigerated & frozen red meats.Not to exceed 10 kGy-Dehydrated enzymes.Not to exceed 30 kGy-Spices.

Radiation Sources Radionuclide or radioactive materials that gives off ionizing gamma rays.• Cobalt-60• Cesium-137

Machine sources of ionizing radiation.• Electron beam.

History of food irradiation.1905- Scientists receive patents to use ionizing radiation to kill bacteria in foods.1920- French scientists discover irradiation preserve foods.1921- U.S. patent is grant for a process to kill Trichnella spirals in meat using X-rays.1958-The food , Drug & Cosmetic Act is amended & defines sources of irradiation for using in processing food.

What foods are currently irradiated. Flour (wheat flour) Potatoes Spices Tea Fruits & vegetables.

Not goods!Irradiation cannot be used for all foods such as Dairy products , Peaches , Nectarines etc.

FDA evaluation Before approvals, considered-•Microbiological safety•Radiological safety •Toxicological safety•Nutritional safety

Process of food irradiation Food undergoing the irradiation process never comes into direct contact with the radiation source. The source is in a room that designed to protect workers & the external environment from the radiation within it. The food is moved into the radiation field via a conveyor belt.The gamma or x-rays irradiating the food like bacteria , insects & pathogens & renders them unable to reproduce & biologically inactive.

How does food irradiation is help?Food is exposed to carefully controlled amounts of radiation.

Radiation damages DNA or microbes & parasitesDiseases causing germs are reduced Bacteria which cause spoilage are reduced.Sprouting is stowed or stopped.

Is irradiated food radioactive?The food itself does not become radioactive because the radiation used in the process does not have enough energy to alter the molecular structure of any of the atoms in the food.

It is therefore impossible for this radiation to make the food radioactive & no-radiation remains after the food has been treated.

Benefits of food irradiation Disease causing germs are reduced or eliminated.Decrease incidence of food borne illiness.Increase level of quality assurance in international trade of food products.Nutritional value of food is preserved.Increasing shelf life of meats , fruits and vegetables.

Electron BeamA beam of electron is accelerated by an electron gun ; similar to a TV tube accelerating electrons towards screen.Electron beams can only penetrate about 1 inch into material.

X-raysSimilar to medical x-rays sources

Gamma raysEmitted from spontaneous radioactive decay.

Effects of irradiationNutritional effects 1. Macronutrients- proteins , carbohydrates ,

fats (unaffected).2. Micronutrients-vitamins (some reduction)

[compared to other processing or storage techniques including Pasteurization , canning , or even cold storage.]

No-change in taste.

Facility accidents & waste Severe accidents are not possibleI. Electron beam & x-rays sources can be

easily turned off.II. Gamma rays sources cannot blow up. The facility itself cannot become

radioactive. No-radioactive waste (used Cobalt-60

gamma sources can be rejected/regenerated.)

How does irradiation food processing operation work

Food is packed in containers & moved by conveyor belt into a shielded room.Food is exposed briefly to a radiant energy source (the amount of energy depends on the food) . Food is left virtually unchanged but the number of harmful bacteria , parasites & fungi is reduced & may be eliminated.

Food treated by ionizing radiation Objectives Foods

Microbial and enzyme decontamination .

Sprout inhibition.

Fruit maturation control.Insect disinfestations.

Extension of storage.

Meat (red meat, poultry, fish) & liquid food (milk juices).

Bulbs & tubers (garlic, potato , onion).

Banana , papaya fruit.Cereals & their products & dry vegetables. Meat & vegetables.

Status of the technology of radiation processing of foods in IndiaIn 1994 Govt. of India approved irradiation of onion , potato & spices for internal marketing & consumption.Additional items were approved in April 1998 & 2001.There is small scale food packages irradiator at food technology division , BARC , Mumbai , which can treat up to 500 kg of onion & potato per hour.

Radiation processes foods be identified in the market (India)Radiation processed foods cannot be recognized by sight, , smell,taste or touch. Codex Alimentarius Commission has endorsed a green irradiation logo.Logo along with the words “processed by irradiation method” & date of irradiation , license number of facility & purpose of irradiation.

Merits over conventional methods

Food irradiation technology has unique merits over conventional methods of preservation such as canning , dehydration , salting etc. as this process does not lead to loss of flavour , odour , texture & freshness.Unlike chemical fumigants , irradiation does not leave any harmful toxic residues in food & is more effective.Since gamma rays have high penetrating power, spices can be irradiated after packaging.

LimitationsOne of the most important limitations of food irradiation processing is its slow acceptance by consumers ; due to inter alia to perceived association with radioactivity.After several market testingThese studies showed that , if the safety and the benefits of food irradiation were properly explained , the consumers were willing to accept irradiated foods.

Thanks………