q Detection of common salt Permissible limit is
q Detection of common salt ØPermissible limit is 3% not exceed that due to its adverse effect on consumer and it added to meat products as preservative and flavoring agent ØDetection of common salt (NACL) %: ØProcedure : üIn A flask put 10 gm. from prepared sample ü+ 10 ml silver nitrate 0. 1 N to precipitate all chloride as (silver chloride) ü+ 20 ml conc nitric acid üThen Boiling gently for 15 min to help releasing of Nacl from meat to binding with silver nitrate and forming silver chloride then cooling and adding 50 ml DW üThen add 5 ml from iron alum Indicator ( ferric ammonium sulphate) üThis also called saturated solution of ammonium sulphate
q Detection of common salt üThen Titration by using ammonium thiocynate 0. 1 N to neutralize these excess amount of silver nitrate till Appear pale brown color ( Permanent color should be stop titration. q. Result : q 1 ml of silver nitrate 0. 1 N =0. 0058 gm. Nacl
q Detction of food additives qcalculation : ØNacl % = (10 - R) x 0. 0058 Ø weight of sample x 100
q Detection of food additives § Def. : these are substances which are added for meat and meat products to : 1. improvement of keeping quality 2. improve appearance , texture , flavor and other organoleptic characters of meat products and preservation action. 3. Retard growth of bacteria
q Detection of food additives ØDetection of Nitrate & Nitrite Ø ( NO 3& NO 2 ) : ØThese add to some meat products as luncheon q. These used for 2 functions : 1. Give product fixed red color along the time of preservation. 2. Strong preservative action to kill some MOs. ( Cl. botulinium)
q Detection of nitrate ØReagent : Diphenylamine. 5 gm ØConc H 2 SO 4 50 ml. ØProcedure : ØIn A porcelain dish add meat sample and then cover sample by reagent ØShaking and mixing ØResult >> Appear of bluish color Ø+ve NO 3.
q Detection of nitrite ( Griess ilosavy reaction) ØReagent : ØR 1 > Alpha naphthylamine solution consist of : Ø 0. 2 gm. of Alpha naphthylamine Ø 150 ml acetic acid (15%) Ø 20 ml DW ØR 2 >> Sulphanilic acid consist of : Ø 0. 5 gm. Of sulphanilic acid Ø 150 ml acetic acid (30%)
q Detection of nitrite ØProcedure : ØIn A porcelain dish add meat sample and then add Equal amount of R 1& R 2 ØResult >> Appear of red color >> +ve for NO 2.
q Detection of Starch ØProcedure : Ølugol’s solution consist of Ø 2 gm iodine Ø+ 4 gm of potassium iodine Ø + 100 ml DW. ØAdd few drops of lugol solution to A piece of meat sample. ØResult >> Appear of dark bluish color +ve Starch.
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