Animal product by marshallshalom

VIEWS: 4 PAGES: 18

Animal product

More Info
									      University of Ibadan
    Department of Animal Science
  ANS 710 (ANIMAL PRODUCTS)
Name: OLAYIWOLA, Abiola Simeon
          Matric No:126417
         Degree in View: M.Sc.

   Coordinated By: Dr. A.B. OMOJOLA

            October, 2012
                                      1
        Title


Nitrite in Meat
     (an overview)




                     2
                 Introduction
• Meat is generally defined as the edible flesh of
  those animals which are acceptable for
  consumption by man (lawrie, 1998)

• Meat are usually obtained from pigs, cattle,
  lambs, rabbit, poultry and venison



                                                 3
               Introduction cont’d
• Biochemical composition of meat
• Main constituents of meat
• Meat Classification




  Fig 1: Meat types
                                     4
  Source: Wikipedia, 2012
                    Nitrite
• Nitrates and nitrites are nitrogen-oxygen
  chemical units which combine with various
  organic and inorganic compounds

• Nitrite is a reactive chemical, and when used
  in biologically complex meat system presents
  numerous reaction possibilities (Cassen et al.,
  1979)

                                                    5
              Uses of Nitrite
• Control the growth of spores (Clostridium
     botulinum)
• Provide cured meat flavor and colour

• Extend the shelf life of meat products




                                              6
       Background information
• Meat has been preserved with salt

• Salt prevents growth of some types of bacteria
  that are responsible for meat spoilage

• Curing process for meats is believed to have
  derived from preservation methods with salt
  as early as 3,000 B.C. (Romans et al., 2001)
                                                 7
               Meat curing
• Production of the thermally stable pink meat
  pigment and cured meat flavour

• Products becomes more tender due to autolysis
  and firmer due to loss of moisture




                                                 8
                     Mode of Action
• Influence on colour
   Nitrates undergo a chemical reaction and are converted to nitrites. Then,
   nitrites react with the protein of the meat (myoglobin), and are coverted
   to nitrosomyoglobin (bright red). When cooked, nitrosomyoglobin is
   converted to nitrosohemochrome (pink pigment)

• Nitrate                 Nitrite          Nitrous oxide              Fe2+
                 binds with the Iron atom at the centre of myoglobin’s heme
   group

• Meat microbiology effect


                                                                               9
Fig 2:Beef (With sodium nitrite) compared to Beef (Without sodium nitrite)
Source: (Milkowski et al., 2010)
                                                                             10
              Nitrite regulation
• Dosage permissible
ppm =
            grams sodium nitrite       x   1 million
            —————————————————
            grams of cured meat sample


• Nitrite Toxicity

• Nitrosamine

• Potential risk Associated
             (methaemoglobinaemia,carcinogens)

                                                       11
                            overview
•   Development of refrigeration and food packaging technologies (Pegg,
    2004)

•    Improved food safety and an extended shelf-life with excellent storage
    stability (Pegg and Shahidi, 2000)

• Antibacterial benefits of nitrite in cured meat products (Milkowski et al.,
  2010)

• Cassen (1997) reported that commercially prepared meat in USA contain
  approximately 10mg/kg NaNO3 when consumed




                                                                           12
                     Overview cont’d
• The formation of nitrosamines can take place only under special
  conditions where secondary amines are present, nitrite is available to
  react, and necessary pH and temperatures exist

• Ingested nitrate or nitrite under condition that result in endogenous
  nitrosation is probably carcinogenic to human (Grosse et al., 2006)

•   nitrosamine formation ingoing nitrite in bacon from( 200 ppm to 125
    ppm)and addition of 550 ppm sodium ascorbate

•    The rule also included the establishment of a nitrosamine monitoring and
    regulatory control program


                                                                            13
              summary
NaNo3 is an effective anti microbial agent.
nitrite used in meat and meat products is
considered safe provided that it does not
exceed the maximum limit for consumption.




                                          14
                conclusion
• Meat curing has been in existence for
  thousands of years especially with nitrite.
• Curing practices in meat have been adjusted
  using the knowledge about nitrosamine risk




                                                15
                            References
Cassen, R. G, M. L. Greaser, T. Ito and M. Lee (1979): Reaction of nitrate in
           meat; food tech.33(1), 4j
Grosse, Y., R. Baan, K. Straif, B. Secretan, F. El Ghissassi, V. Cogliano (2006) :a
           Carcinogenicity of nitrate, nitrite, and cyano bacterial peptide toxins.
           Original Text. Lancet Oncol. 7:628–629. WHO International Agency
           for Research on Cancer Monograph Working Group.
Jeffrey, I. S. and A.. L. Milkowsi (2011):Sodium Nitrite in Processed Meat and
           Poultry Meats: A Review of Curing and Examining the Risk/Benefit of
           Its Use: America meat science association AMSA white paper series
           number 3
Lawrie, R. A. (1998):Meat science. Pergamon press,oxford.6th edition.
Milkowski, A., H. G. Grarg, J. S. Coughlin, and N. S. Bryan (2010): Nutritional
           epidemiology in the context of nitric oxide biology;A risk-benefit
           evaluation for dietary nitrite and nitrate. Nitric oxide 22:110-119


                                                                                 16
Pegg, R. B. and F. Shahidi (2000): Nitrite curing of meat. The N-
        Nitrosamine problems, nitrite alternative. Food and nutrititive
        press Inc., Tumbul, CT.

Pegg, R. B. (2004):Curing. In encyclopedia of meat science. W. K.
        jensen, C. Devine and M. Dikenan, ed Elsevier Ltd., Oxford UK.

Romans, J. R., W. J. Costello, C. W Carlson, M. L. Greaser and K. W. Jones
       (2001):The meat we eat. 14th ed. Interstate publ. Danville, Ilpp.779-
       887.




                                                                               17
Thanks for Listening




                       18

								
To top