الفهرس | Only 14 pages are availabe for public view |
Abstract H1e warm climate 1s prevailHHJ almost all tt1e year 1n fgypt. wlt11 tile lack of refrJgcratlOn tac1l1tleS. Also. poor hyg 1 c~rn c standarclc;. h1 gh amb1 ent temperature and the 1 nferi or t1ancJl ing methods hl~Jllly contribute 1n h1gher· rn1crob1al counts 1r1 raw m1lk. conspquently low keep1ng quiJllty I herefon’. some rm l k producer’S 1 n Egypt used to add some ct1ermca1 pr·cservatives into m1lk to cll~Stroy and/or Inhibit the rmcrofloru. und t1cncc to prolong the cxpiri:ltion period. it:. UlP keep1ng quality. Prest-~r·vatives most con-manly used are fornrdl·rn (40%) aqueous solut1on of For’maldehycle. hydrogen peroxide. soclium bicarboni:lle for their l1igh efficiency against many rmcroor·ganisms. cheap prices and easy to obta1r1. Formalin is J strong antiseptic and clisinfectant for var10us kinds of l)acleria. Several invrstlQJtors studied tt1e effect of formal1r1 as a mllk preservatlVe. Karoly (19441. Sollman (19571. Hrock Neely (19631. V1ttar1o et al (19661. El ·Sadek et al (1%91. Abo·El Naga et al 09721. Corrad1m and Batt1stolt1 (l98ll. Suhren et al (19811 and Mahmoud et al (1985). Also. Fonnal1n is added to d1eese milk to overcome cJifficult1es r’PSllltlng from U1e use of r·aw milk. It t1as a ser10us UetPriortlted E:’ffect on health when preserrl in t119h concentrations. IL lS 1llegal to use Formal in as a food preservat1ve. however some cheese rroduccrs are keen to acJcJ formalin to ctwesr m1l k during tt1e manufacture of Domi att i cheese. The )·~yclmt_H.’n prroxlde IS r:nns1der·crl as i.l SdfP prc’SCI’VdLivP few r111lk t~mllPqitlmi.ll\’lY lJP ernrloyc:<.l dL lewls IJPtween lOO·BOO pprn (FAO, 19571 Tilf’ IJI’Ope:·tlC\ of hydro~en peroxide as a rmlk pr,eservaLJve in dJ1ry 1ndustry have been 2 known and invl’stlguted for many years. Some results cleared thJt unsat1sfactory flt~vour. bocJy and trxtur’e wer~e shown in tile ciJPese (KosJkowskl. 1977: Jha. 1984) Also. some loss 1n biOlogical value uf pmteins and availalnllty of· sulphur’ conta 1 n 111g dllllno ac1 ds were reconled by E I ·Magdoub ( 1971 l: Slwhota et al (]97Sl a11d Oeodllar and Mehta (]~eOl. Sodium b1 ca r’bonate was a 1 so known dS a preservative and adcJccl by sever”al pr·ocJucer·s in trop1cal and sub-tropH:al counlncs to control U1e pH of raw milk cJur-ing summer (Huhn c•t ol. 1991: Kukdc• et di. 19911. Althouql1 Sodmn bica1·hnnatc lS ppnn1ttcd 1n son1t’ nJ~IrltriPs, as a milk pr·cservcJtlVe. sucll rr11lk is cuns1clerr:d dS <~lmonnJl lllllk 111 SOPll’ others (Ka1ser !992) . Th(-~refore. tllis investigation was plJnnPd to study U1e effect of some prcservut1ves as formalin. hycJr·ogcn peroXlde and sodium bicarlmnat(: on tJ1e quallty and microbial flora of m1lk and soft c!leesr:s T~ll c_; a i rn was upproJctwcJ through Ul ree j)d rts . wl11 ell d re: A survey slwly un 1llegal preservatlvPs Hl l’dW rmlk Jlld soft cheesrs nvailable in diffcrenl rnar,kets. II [ffect of some lwdL treatment proet’<;SPS on rilw mrlk contaimng c;omc lllegul preser’VdtlVCS. !II [ffpc:t of dCkling some illegal preser·vat·ives on clotting JCtlvlty or r·r’nne |