BACTERIA AND BUTTER.

Otago Witness, Issue 2569, 10 June 1903, Page 6

BACTERIA AND BUTTER.

For some time pi.?i haclei'.a have heen. in the popular mind, ii byword for producing all the diseases that fle-\ is heir to. and for promoting to a very large extent that decay inseparable fr.im a living woild Day by day this impie-F.ion of the general cwlness- of their irork has been confiimerl, the disLovery of the luber.-'e bacillus in consumption, of the b<villus irducii'g cholera, of the organisms 111 diphthe/i.*, a id o^ niu.ny oilier disease geims all tending to widjn the distru&i. of the whole genu-. It 11 tmo that our knowledge relating to them I=, % cry new — indeed, it is well within the la&t 20 yeais that bactc-r.o'.og\ h is become a fettled a' d organised biaiiLu of Ihe g! eater .-.udy of the whole pi nit kingdom- bat during th.it time little go.,d hi^ been placed to their account.

The recognition of the sennes that hactcna may lender to the d-'pailmfnt of da ry farming i*> qu.ie a ikw ue\fh*pmenl, atid h^.c" wl' quote a .-taudud aalliouty on th^ •-übj'-^t -■?'(■".- that baci.l a ha\t? a^lll- ,',''\ l-cui cultnatcd for t.-s in butttrjiiiikiu^, and ii.it th> inltuie.s may b • liou^hi — in latt, tliat a d(-!i')it'i ttade has b en oi^.inised.- -.1 .it tiisL .s.^iit iom<wlnt ht.atln. r .No'\, luitter miy be m.ido e'lui r'.uly fruin fu v h. saeet civ <i in , 0., <". , i) nioie u«uil, lioni cream wliuh h..s boen

(o'htt d ft om ci'h d iy\ milk and kept 1 !• iL.tns a week before the churning, by 1 w li.lli t'in° it has turned dis>tin'.tly *m,v Hit ttr made [rum the fie^h cieam Ins a dt'itiou^. delu.itp ,101111, *!ioulli th clt>hc if .- 01 the Ihmc leu\es- it open at times' in the ch.u,'t; <it niMpidiu ; l;iit it hi" cn° ' -ci mi. cl V tv • v is not neuL ;. , \a'u,'ble ' .« (om'neu\il piodtiLt as buittr midj from ' ihis j-oiuvd cia-n. -iik c it is defect .ye in 1 ' ke^jiiiL^ ' qu.ihiv. liuttet ficun mhii ae.ini ' ha- .(. nioie i»iiinouiited ilivoui, .md is net ' 'pute «.() sweet, but i.nc.i^d c \;n>] nnt-it- j h.i\e siuiHii thai wiieu butu! i- to bt kept ' fo»f o» .ai; ' ii/th 01 nine in u--e,l tor t\.{,c>ri.i ton 01 . j<!i- (U al iv ki. d. tla-n 11 1 be^t »-' - '•• '"'" !n th<^ Man 01 '1,.,." ti-.m, of a l'.'ht ri^iee of 1 ineup-a, At the (\ntr.d I \per>mi'inal Fimh l).i,'\ Mi]i|ioitid by !''• (' Illd'U) ( irtPlPl'Hlt f,.l :h. 1,-n. !■"».

'•f ih.t w!um, tl.e in.lt rI. .> |k iU well iiiiL'-lit-d out in the nitdt-!-. of tlit- e.\-1.->itPi-. wiili tiie lt^ult th.it bit; r f-om - . eet iMsn wt s foiml i,, | )e „] % „ m !jU i (Iml pi ,i]\ ( \,,miii .tiori- fmni t.in (<» ti ne ]>i> tit^ioud .^ „ \,|iu..h!e nM.'ir-, A j,-o-ir i t'l.ui luii u-i limn .i portion of ihf "- ,me ' tarn whi. h h-l betn Mi't.ibly '.-Miird' <-i " upened ' bif ( ,ie chin niii^. "in J-'n.n.e .c-d (iei-many nenh the whole <.f the bilttfr is nude fu:m w (in S ] L fie ,un, and alvo th -t >wirs buttoi whil. i- intended for imnui t.itioi .nto \\u^, *hM the Lon timers then* I'icJei the l!a\i,vii-. and. mo.co.c!, hn.i it • L - e;^ ii' i-c »'t'-f,i. to ilv

lor .«• ,mo ( . n ,^ ii P S)Un ,,_ i (|f b ni] croain in. li v I, ie.n.rnivd as th- n,"L ul certain bicteiia, vlndi. acting on the mi^p of the milk, produce Ictctie 'ieraients. aid microscopic examination of milk in \ tr.ous -ta^es of boui:ng or m faulty t..nditio>i. Mich a-- "blue" milk, ".sti incjy ' milk, etc '•hows that b.icteiia vie ,il» l n> pie-;-^at — not of one or two Laid*,

but of many different varieties, certain kinds predominating according to the condition of the milk. This being the case, it follows that the relation between bacteria and milk is of vital importance to dairy f;<rmers, and certain eminent Ivicleriologists, chief among whom mu.-t be ranked Dr Weigmann, of Kiel, have been engaged in investigating it, and with definite results hereafter stated.

Cream turns &our because certain bicteria devtlcp in it. Those may be derived from different source' — fiom the a.ir chiefly, from the udder of the cow, from the ttablinej if the cows are stabled, or elsewhere. Hence they are a mixed assortment, with varying properties, .good and evil. Some piodnce a feiment A^hich gives to the butter a rancid flavour, others may induce a soapy taste, and some again give the aromatic flavour characteristic of the be«t dairy butter, and so forth. It all depends, on which kind of bacteria predominate whether the butter will be good, bad, or indifferent. Even in the heft dairies the quality varies, at tune 1 ;, though whtn there is scrupulous cleanliness observed the risks of evil bacteria beinif intr-duced aie greatly mini-mi-rd, but onoe introduced all develop equally well in the milk, fio iv an nrticle avpe:sxing in the t-thleswg-Hoktein Weekly Journal of -Agriculture in July, 1890, I)r Wei^mann a^krd the question. Whether it would be poi'ifuk". and if positb'.e advantageous, to isolate those bacteria essential to the b a st r ; ]v^T:lng of the ennm from those Avlnch n:"C u c cle«!s and inferior, and thus prepare a pure culture wh-ch, added to any sterilised cr^am, would give butter of the puri-t pii^ b!e quality and the fine' l tiavoui '! He made the experiment; obtained a pure culture of the acidifying h?rteria. add'd it to pasteurised cre?m (that i~. to cream which had been absclutely f'.Ctd fio:u ail germs •whatsoever), and churned ihe cieam ii'to hutter. The butter Mas of absolute purity, and kept well for a length- of tune, but failed in a most hn-jvort-ant particular — it had no aroma, no flavour; it v, as "faultily faultless, splend.dly null." He theieupon set out in t-e irAi of a bacterium which would give ck--i-ed iiavour as well as good keeping qtnlitios, and for this purpose 113 obtained iiP".m from ;• dairy celebrated for the very fine qual ty if its butter. This cream when sour »vn« found to contain chiefly one pa 1 titular bacterium, so he isolated and cultivated it in his laboratory, obtaining a pi.ie cultaie. Again he etcrilised his ci-fiin, sound it by introduLing the new niliurp, <uid .s^t ii.m^-elf to bulter-i.iak:n<r, but ill without satisfActory rcmlU ; for, Ih')u,'h the butter he now obtained was of sjil°!id-d flavour, yet its quality for keeping, and therefore its commercial value, left much in hs desired.

Tlie coii'jliiMon, then, that Dr Weiqmann dreir from his work fo far was this: that tliere pre rot one or two, but many, backnia which lwve the power of turning trea,m sour in the legitimate process of buttcr-mikint,', bul ifc appears that tho-e bact'i'li which give a desirable flavour do not yi\ e this t^iality with stability