Published on

Published in: Technology, Health & Medicine
1 Like
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • The policy is to first decide on the outcome you are trying to achieve and then use the minimum amount of radiation that will achieve that result.
  • I’m sure you’re familiar with the electromagnetic spectrum that includes radio and television waves, microwaves and visible light. But ionizing radiation has shorter wavelengths and consequently higher energy---enough energy to break chemical bonds in molecules resulting in chemical changes in foods and the insects that contaminate those foods.
  • The two main sources of ionizing radiation are (1) gamma rays from a radioactive source, primarily cobalt 60, and (2) high energy electrons or x-rays produced by an electron beam accelerator.
  • Extensive research over the past five decades has established the safety of ionizing radiation as a food processing technique.
  • And today as you can see, most of the developed countries of the world have approved food irradiation of some type. Currently more than 100 million tons of food are being iradiated and used by consumers. SHOW BOOK Here in the United States we have been on the slow side in adopting this technology….it seems clear that he main reason for this is the publics attitude toward a technique that involves radiation treatment. Yet where irradiated foods have been offered along with an informational campaign, the public is willing to pay a higher price for the irradiated foods. Why then do we need ways to detect the irradiated product?
  • Impedance is th etotal opposition to the flow of current by a circuit…the vector sum of the resistance and reactance.
  • From Japan where upwards of 20, 000 tons of potatoes a year are irradiated in a facility like this one, came a study from their agriculture department on potato impedance which reported that at low frequencies radiation produced a measurable change in impedance while at higher frequencies the difference disappeared. So by finding the ratio of the low to high impedance of a group of irradiated potatoes and comparing that to a group of unirradiated potatoes, a distinction could be found.
  • OUM-NESTLE 2008 3

    2. 2. SUB-TOPIC: FOOD CONVERSION AND MANUFACTURING <ul><li>Cooling and Freezing process. </li></ul><ul><li>Concentration & Dehydration: Concentration, Spray Drying & Vacuum Drying process. </li></ul><ul><li>Industrial Fermentation process. </li></ul><ul><li>Irradiation Process. </li></ul><ul><li>Homogenization Process. </li></ul><ul><li>Wet and Dry Mixing process. </li></ul><ul><li>Transport and Conveying process. </li></ul>
    3. 3. Radiation: Form of energy <ul><li>What is the Radiation? </li></ul><ul><li>RADIATION: “The emission of energy through space or material in the form of waves”. </li></ul><ul><li>Electromagnetic radiation? </li></ul><ul><li>Waves or rays in the electromagnetic spectrum. </li></ul>
    4. 4. Electromagnetic Spectrum
    5. 5. What is irradiation? <ul><li>Application of high energy to products, including food. </li></ul><ul><li>The reason we used irradiation: To sterilize or pasteurize by killing harmful insects, bacteria, parasites and mold. </li></ul><ul><li>Preservation method that uses short waves of the electromagnetic spectrum. </li></ul>
    6. 6. What non-food products are irradiated? <ul><li>Personal hygiene products </li></ul><ul><li>Toothbrushes </li></ul><ul><li>Bandages </li></ul><ul><li>Floss </li></ul><ul><li>Surgical packs </li></ul><ul><li>Toilet paper </li></ul><ul><li>Q tips </li></ul><ul><li>Feminine products </li></ul><ul><li>Cosmetics </li></ul><ul><li>Some tires </li></ul><ul><li>Many more </li></ul>“ These undergo radiation treatment in Co-60 (Cobalt-60) facilities throughout the United States”
    7. 7. Sources of ionizing radiation <ul><li>1. Gamma rays </li></ul><ul><ul><li>Co-60: The most common radioisotope used (Food Technologies Inc, & Mulberry) </li></ul></ul><ul><ul><li>It has the deepest penetration. </li></ul></ul><ul><ul><li>Used to sterilize many non-food items. </li></ul></ul><ul><ul><li>Can be applied to various foods, sizes, shapes </li></ul></ul><ul><ul><li>Raises consumer concerns = Radioactive residual in the items. </li></ul></ul>
    8. 8. <ul><li>2. X-rays </li></ul><ul><ul><li>Machine that produced the x-rays are powered by electricity. </li></ul></ul><ul><ul><li>A lot of consumers in the world are familiar with the technology. </li></ul></ul><ul><ul><li>Widely used in the health care treatment. </li></ul></ul><ul><ul><li>But unfortunately, it is not yet widely adopted for food application. </li></ul></ul>Sources of ionizing radiation
    9. 9. <ul><li>3. Electron beam: (  ) beta rays </li></ul><ul><ul><li>Machine that produced electrons which is powered by electricity. </li></ul></ul><ul><ul><li>It is a short penetration and it requires a thinner product in order the rays being penetrated. </li></ul></ul><ul><ul><li>Works well with meat pie </li></ul></ul><ul><ul><li>Company that used this source: Titan facility- Iowa, USA. </li></ul></ul>Sources of ionizing radiation
    10. 10.
    11. 11. How does radiation work? <ul><li>1. Direct Effects : Kills microorganisms by damaging bio molecules in cells </li></ul><ul><ul><li>Photons of radiation hit electrons in atoms of microbes or food molecules. </li></ul></ul><ul><ul><li>It transfers energy to the electrons. </li></ul></ul><ul><ul><li>Electrons scatter and collide with other electrons. </li></ul></ul><ul><ul><li>Chemical bonds are broken, disrupting cell metabolism and other cells division (DNA and RNA and cellular proteins) </li></ul></ul>
    12. 12. <ul><li>2. Indirect Effects : Water molecules in organisms or food undergo radiolysis (disruption through radiation). </li></ul><ul><li>It will form a “free radicals”: atoms or molecules having an unpaired electron. </li></ul><ul><li>Then, it quickly combines with oxygen to form oxidizing agents that damage bacterial cells and eventually leading to death of organism. </li></ul>How does radiation work? “ The combined effects (indirect & direct) can result in the destruction of target organisms efficiently”
    13. 13. Measure of radiation dose <ul><li>Unit is the “gray” (Gy) </li></ul><ul><li>FDA uses kilogray (kGy) = 1,000 grays </li></ul>
    14. 14. (1) Low dose: 0 - 1 kGy <ul><li>Disinfest grains of insects </li></ul><ul><li>Inhibit the developing of microbes. </li></ul><ul><li>Control Trichinella spiralis in the pork meat. </li></ul><ul><li>Delay ripening in fruits and vegetables. </li></ul>
    15. 15. (2) Medium dose: 1-10 kGy <ul><li>Reduce the availability of the microbial pathogens in the meat, poultry and fish </li></ul><ul><li>Reduce spoilage of microorganisms. </li></ul><ul><li>Delay the mold growth on strawberries and other fruits </li></ul>
    16. 16. (3) High dose: 10 - 50 kGy <ul><li>Kill microorganisms in spices and herbs preparation ingredients. </li></ul><ul><li>Commercially to sterilize the food. </li></ul><ul><li>Disadvantage: It can cause the functional ingredient in food to modify. </li></ul>
    17. 17. <ul><li>RULE OF THUMBS: </li></ul><ul><li>Complex organisms require LESS radiation to affect or destroy them. </li></ul><ul><ul><li>Simple organisms like bacteria take higher </li></ul></ul><ul><ul><li>doses to be destroyed than insects. </li></ul></ul>
    18. 18. Effects on food products? <ul><li>Foods do not become radioactive after being exposed to the irradiation process. </li></ul><ul><li>But some chemical changes may occurred. </li></ul><ul><li>e.g: Unique radiolytic product can be formed: 2-dodecylcyclobutanone (2-DBC) </li></ul><ul><li>No toxic effects, not mutagenic. </li></ul><ul><li>Food also changes when it is cooked = so, expect the same effect the irradiated food products. </li></ul>
    19. 19. Irradiated of “Cold product” <ul><li>There is a small effect for certain nutritional compounds if any of the chilled food product increases in temperature during the irradiation process. </li></ul><ul><li>But no changes in physical appearances occurred. </li></ul><ul><li>e.g: At 1.5 kGy or 3.0 kGy for the ground meat. There are: </li></ul><ul><ul><li>- No adverse effects on thiamin or riboflavin (crucial amino acid contents). </li></ul></ul><ul><ul><li>- No negative effects on meat color. </li></ul></ul>
    20. 20. Grilled food Frozen food
    21. 21. Regulated by the U.S. Food & Drug Administration (FDA) <ul><li>The irradiated food has be used as a food additive since 1958 under the Federal Food, Drug and Cosmetic Act of 1938. </li></ul><ul><li>Various irradiated product has been approved by the FDA since 1963. </li></ul>
    22. 22. Irradiation Approvals
    23. 23. Past decade <ul><li>In 1993, food borne illness from E. coli O157:H7 has infected USA - Hundreds were ill, several were deaths. </li></ul><ul><li>Source of the infection: associated with the ground beef. </li></ul><ul><li>Because of the E. Coli were widely spreaded, US government has approved for the irradiation of meats to inhibit E. coli. </li></ul><ul><li>The effect: It was a great reduce of the pathogens in the ground beef. But it does not sterilize the product from other microbes. </li></ul>
    24. 24. Regulation on Meat by the FDA 1997 & USDA 1999 <ul><li>For the uncooked meat and its by product: </li></ul><ul><ul><li>- Refrigerated meat: the radiation can be used up to 4.5 kGy </li></ul></ul><ul><ul><li>- Frozen meat: up to 7.0 kGy </li></ul></ul><ul><li>The HACCP system should be implemented along with the irradiation process. </li></ul><ul><li>Labeling of consumer foods should be imprinted: </li></ul><ul><ul><li>-e.g: “Treated by electron beam irradiation” </li></ul></ul><ul><ul><li>-e.g: “Treated to reduce pathogens such as Salmonella ” </li></ul></ul><ul><ul><li>-e.g: “Irradiated ground beef”. </li></ul></ul>
    25. 25. What Is Food Irradiation? “ Food irradiation is the process of exposing food, either packaged or in bulk to carefully controlled amounts of ionizing radiation for a specific time to achieve certain desirable objectives”
    26. 26. Ionizing Radiation Ionizing Radiation: “X-rays, alpha, beta, and gamma rays (short wavelength-high energy) which cause whatever material they strike to produce ions”
    27. 27.
    28. 28. BENEFITS OF FOOD IRRADIATION LOW DOSE (up to 1 kGY) (FDA approved for grain, fruits, vegetables, and pork) <ul><li>Inhibits growth of sprouts on potatoes, onions, and garlic. </li></ul><ul><li>Slows ripening process, keeping fruits and vegetables from spoiling by a few days (e.g.: mushrooms) to a few weeks (strawberries). </li></ul><ul><li>Kills insects found in wheat, flour, fruits, and vegetables. </li></ul><ul><li>Eliminates parasites such as trichinosis -causing the appearance of parasites colony in pork. </li></ul>
    29. 29.
    30. 30. <ul><li>Extends shelf-life of fresh fish, strawberries, etc. </li></ul><ul><li>Reduces or eliminates spoilage and pathogenic microorganisms and parasites like salmonella . </li></ul><ul><li>Inhibits mold on fruits. </li></ul>BENEFITS OF FOOD IRRADIATION MEDIUM DOSE (1-10 kGY) (FDA approved for poultry)
    31. 31.
    32. 32. <ul><li>Sterilizes food for hospital diets of those with immune system disorders . </li></ul>BENEFITS OF FOOD IRRADIATION HIGH DOSE (10-50 kGY) (FDA approved for spices)
    33. 33. Safety Issues for the Consumer <ul><li>Radioactivity? </li></ul><ul><li>Chemical changes? </li></ul><ul><li>Nutritional qualities? </li></ul><ul><li>Microbiological mutations? </li></ul><ul><li>Genetic changes? </li></ul><ul><li>Effect on food additives? </li></ul><ul><li>Packaging? </li></ul>
    34. 34.
    35. 35. Need for Detection Method <ul><li>The International Food Trade Organization (IFT) is developed to assure that all manufacturer that used irradiation method has to compliance with regulations </li></ul><ul><li>Protect freedom of information and choices for the consumers. </li></ul><ul><li>Protection from fraud information </li></ul><ul><li>Make enforcement of labeling that uses the radiation so that consumers will fell confidence with the food products. </li></ul>
    36. 36. Types of Detection Methods <ul><li>Chemical </li></ul><ul><li>Biological </li></ul><ul><li>Physical </li></ul>
    37. 37. Status of Physical Methods
    38. 38. Applications (Physical Methods) <ul><li>(1) Impedance </li></ul><ul><li>-Potatoes </li></ul><ul><li>(2) Viscosity -Pepper </li></ul><ul><li>(3) Chemiluminescence </li></ul><ul><li>-Spices, herbs </li></ul><ul><li>-Dry vegetables </li></ul><ul><li>(4) Thermoluminescence </li></ul><ul><li>-Spices, herbs (minerals) </li></ul><ul><li>-Fruits, veggies (minerals) </li></ul><ul><li>-Shellfish </li></ul><ul><li>(5) EPR </li></ul><ul><li>-Meat, poultry, fish </li></ul><ul><li>-Nuts, dry fruits/veggies </li></ul><ul><li>-Fresh fruits </li></ul><ul><li>-Shellfish </li></ul><ul><li>-Whole eggs </li></ul>
    39. 39.
    40. 40.
    41. 41. IS THERE A SIGNIFICANT DIFFERENCE ? ANS: *Not much significant differences-The mean values is more less the same*
    43. 43. EPR TESTING
    44. 44. Electron Paramagnetic Resonance (EPR) <ul><li>EPR is a spectroscopic technique that detects chemical species that have unpaired electrons. </li></ul><ul><li>A great number of materials contain such paramagnetic entities, which may occur either as electrons in unfilled conduction bands, electrons trapped in radiation damaged sites, or as free radicals, various transition ions, bi-radicals, triplet states, impurities in semi-conductors, as well as other types. </li></ul>
    45. 45. Requirements of a Detection Method <ul><li>Discrimination distinct and separable radiation-induced response </li></ul><ul><li>Specificity response not induced by other processing </li></ul><ul><li>Robustness </li></ul><ul><li>insensitive or predictable response </li></ul><ul><li>Reliability </li></ul><ul><li>Stability </li></ul><ul><li>Confidence </li></ul><ul><li>Practicability </li></ul><ul><li>rapid, simple, low cost & wide applicability </li></ul><ul><li>Dose-dependence (quantification) ideal dose, not too much and not too small </li></ul>
    46. 46.
    47. 47. Food irradiation <ul><li>It involves subjecting the food to a close ionizing radiation (gamma-rays). </li></ul><ul><li>Effective & safe method of extending shelf life of food. </li></ul><ul><li>It destroy parasites, insects and microorganisms. </li></ul><ul><li>DISADVANTAGES: Microbial spores & toxin unaffected. </li></ul><ul><li>Food that commonly irradiated-spices, chicken, onions, potatoes & strawberries. </li></ul><ul><li>Doses used vary with the products. </li></ul>
    48. 48. Irradiation <ul><li>Spectrum of electromagnetic radiation </li></ul><ul><li>(a) Short wavelengths (high energy) = ionizing radiation </li></ul><ul><li>(b) Long wavelengths (low energy) = radio waves </li></ul><ul><li>(c) Middle wavelengths = visible light </li></ul>Microwaves Long wavelengths Heat food by making water molecules move very fast Ultraviolet Shorter than visible wavelengths Can kill microbes Only used for surfaces Ionizing radiation Beta rays (electrons) Gamma rays (from radioactive source)
    49. 49. <ul><li>Measuring radiation </li></ul><ul><li>Curie - Quantity of radioactive substance </li></ul><ul><li>Rad - Unit of measure for absorbed radiation dose </li></ul><ul><li>Gray - New unit of measure (= 100 rads) </li></ul><ul><li>What does radiation do? </li></ul><ul><li>Damages DNA </li></ul><ul><li>Causes chemical changes in the cell </li></ul>
    50. 50. Radiation vs. microorganisms <ul><li>Different organisms vary in radiation resistance. </li></ul><ul><li>Some very resistant types exist. </li></ul><ul><li>More cells present means more radiation needed to be used to destroy their cell walls. </li></ul><ul><li>Non growing cells are more resistant than growing cells. </li></ul>
    51. 51. How to choose the right dose? <ul><li>Target size: Smaller the target, more radiation to be needed. </li></ul><ul><li>Desired effect: </li></ul><ul><ul><li>- Inhibit sprouting? </li></ul></ul><ul><ul><li>- Kill insects? </li></ul></ul><ul><ul><li>- Kill some bacteria? </li></ul></ul><ul><ul><li>- Kill all bacteria? </li></ul></ul><ul><li>If possible take the lowest dose to do the desired job = less radiation during handling. </li></ul>
    52. 52. Examples of irradiation processes Control insects in fruits and vegetables up to 1 kilogray Kill insects and microbes in spices up to 30 kilogray Control Trichinella (a parasite) in pork 0.3-1 kilogray Inhibit sprouting of potatoes 50-150 gray Control insects in wheat and flour 200-500 gray