No. 4, V O L . XXXI1. Canadian Section. Jfleefitig hekd al Torotilo, 0 t h Tlruraday, Jnntrwy lGLh, 1013. PIIOF. WALLACE 1' . COIIOE I S TKE CIIAIR. THE SCIES!L'LFIC BDVAXCEJIEWL' OF THE CASNING ISDUS'I'RY. 1IY 11. T. NOII.\S, 31.X.
Tlic prcwrving of foods has its bnsis in the work of Pnstcur (I822-18%), lint even i o p n r s before his rcscnrches wc linvc, in li9.5, n process inrented by n Prcncliman, Appcrt, for preserving foods in Iicrnicticnlly senled receptncles, nnd this process wns nwnrtlecl n prize of l(i,ooO frnncs by the Frcnch Govcrnnicnt. This process conshtccl in plncing the nrticlcs t o bu ~ircscrved in corked rcccptnclcs, nnd thcn subjecting thcsc to tho lient of boiliiiq wntcr for varying lengths of tinic depen~lcnt on tho nntiiru of tho foods. Notiirnlly this ~i r i ~c s s of Alipcrt wns kept as sccrct RS possil)le, but t litr inforinat ion grndunlly lcnkcd out. and in 1815 wns brought from Ihgland to Aincricn. In l81!) nn Englishmnii nnnic-d Dnggett hntl (5 cnnning fiictory in Ncw York City, for packing lol)stcr, snlinon, nnd oysters, nnd in 18% fruits nntl vcgctnblcs w i w cniuicrl.
In thwa cirrly tlirys glnss jnrs only wcrc nscd, Iint thcir cost, brcnkngc, ctc., lctl to tho nsc nf tin cnns. tho first pntent for which wns secnrcd in Kii!$m(l in 1823, nnd in Amcricit in 1825. T11c cnm wcrc ninde in the cnnning factory, nnd tlicir ninnuhcturo wns slow liut interesting. Thc grcntest dificiilty \vns ckpxionccd in ninking the tops niid bottonirr, X \vc.iglit \vns pulled rip to tho ceiling nntl nlloscd to drop on 11 sheet of tin ; n die \vns cnst in the undcr side of the weight, nnd tlic opposite die wns cnst in n plccc of nletnl h h J \ ~. Ti1 order to guide the weight n n that tlic dies aonltl strilic in the proyr plncc, two upright Croovcc! guirlca were nintlc, xiiiiiliir to tliow of 11 pilc driver. lhe Iiotfy of the cnii ww rnntle on n cylintlricnl form, the cdgcs were butttvl toxctlier nntl soldcrctl, nnd tlicn tlic tops nnd liottan~s sioltlcrctl on.
Crntlunll-, Iiowevcr, Innchincry was dcvclopccl for ciinnmking, rr&l to-thy tiic process of ~irotlnction of finislictl cnm froin sliwt tiri plntc is nutonintic nntl coritiriiroiis, nnd tlic industry is vnt ircly xcpnrntc froin tlint of cnnning, nlthougli ninny cnnniiig cornlicriiics work thrir own cnn-I , -.
ninking pltiiits.
uscd for stcrilisntion of the foods.
In thu originnl Apiicrt process only boiling wvutcr wne
This wns found insuficicnt for intiny products, t i ~, Intcr on, snlt wns nddcd t o the writcr to ruiso tlic boilinn point, tind this wns nfterwnrde supl)lt!nicntcd by the ciddition of cnlciuin cliloridc.
SO tlrnt tcinpcmtiircs lip to 240' P. could be produced. In 1871 n llnltiniorc ninn invented n closcd rcrtort for aooking with snpcrlicntctl stcuni. Thk Icd t o our niodcrn retorts or nirtoclirws, which protlucu vnrioiis tcnqmnturcs froni 212" F. np, clcpenrling on tliu stcnin prcssurc iiscd. Althoiigli t l i P industry clirtes bnck t o 1705. it wne cond ~c t e t l for 11 long tiniu ciitircly without nnp knowlcdzc of tlru rcnl Ruiciit ifio principles iriulcrlyiiig tliu 111~thodH in IIYU, y t l it ia intcrcst.ing t o look nt ~o n i c of tho cnrly thcorics iitlvrincctl. T11u first tlicory wns tiint of tlic cxdusion of trir. This wns rccopni.sct1 by Apport , who stntcd tlirrt it ivns the cxtcwiiil nir wliioli cnii~erl spoilii~c ntid not tliu nir in tho jnr. Giiy-T.ussiic, who WIIR inHtriictcd Iiy t,lic E'runch Covc!rnnicnt t o invcstigirtu A p p i ~t ' s praccs~. Tc}!Ortcd thnt npoilngo oi food wis cniisccl by n suries of oxitlirtion oliirngiw, Riid by drnwing out tho irir iind prcventing it8 getting in agriin tlicsu oxitlntione wcru provuntetl. 1'1iis thuory tliiit tho nir niust bo uxcludcd W ~H folfowutl up to rccctnt tinwi, in cvideiico of whiolr ws ace, ualy L) fuw ycara ngo, tliut onns wcrc ncnlcd, lrontcd, vented