THE RIPENING OF CHEESE.

Waikato Times, Volume XIX, Issue 1639, 6 January 1883, Page 4

THE RIPENING OF CHEESE.

Mncu has been done duriiu' recent years to extend our knowledge of the functions ot many minute microscopic organisms in certain important and well-known processes connected with agriculture^ As an example, m.vy be cited Sehlosing's discovery of the organic ferment concerned in the formation of nitrates in the soil. Another case of great inteieat to dairy-fanners is that afforded by ceitain microscopic organisms which play an impoi tout part in the ripening of cheese. Last year, Mons. K. Duclaux conducted at the dairy station of l'\ui, in the department of Cant.il, a series of observations directed to the object of still further elucidating this matter, and the results have recently appeared in a French journal. Tt appears that these microscopic organisms develop at the expense of the casein of the cheese, the fat, as a rule, remaining unaltered. This is what might naturally be expected, inasmuch as the casein can provide the organisms with nitiogen, which the fat is unable to do. The casein serves as the nutriment of the fermentative organisms ; as a matter of fact, they feed upon it, and, in doing so, they break it up into a regular series of chemical products. It is inteiesting to learn that the flavors which characterise different kinds of cheese aie due to various mixtures of these decomposition products, though they are present in extremely small proportion, and act, thcrcfoie, somewhat after the fashion of condiments. The living cells of the ferments can exist only on surfaces in contact with the air, but from them proceeds a fermenting substance called " diastase," which efFects decompositions of the casein thioughout the entire mass of the cheese. Theie are two kinds of diastase, one resembling rennet, and possessing the property of coagulating milk, though it is unable to again dissolve the coagulated matter, and a second form which can re-dissolvo the coagulated casein, it is the latter vai iety which plays the chief pai t in the ripening of cheese, the coagulated casein being always, however, first obtained by the action of rennet. The second vaiiety is known as digestive diastase, and in a few days it can conveit curd into substances having all the appearance and consistency of Brie or Camcmbeit cheese, but quite tasteless, inasmuch as they lack the ilavoiiiing constituents which have aheady been lefoired to as the direct product of the growth of microscopic oig-nnisms. The coagulating diastase (the one first mentioned, which results fioni the living ferments of the cli'jcse) is similar to the fcimont of the &«une name which occurs in the icnnct, so that a brief account of the properties of lennet diastase will give us equal information respecting the coagulating diastase of cheese. The active portion of lcnnetis, as usually prepared, as is well known, the diicd mucous membrane forming the interior lining of the calf's stomach, ltsgianules contain numerous micioscopic tei ments, which, as soon as the calf is killed, and during the time occupied by the (hying of the lennet, secLotc the active diastase. Consequently the coagulation due to the rennet is effected in the same way as that sometimes brought about by the use of a piece of old cheese. The multiplication of the micioscopic fermentative oiganisms and the lesultinc; increase of diastase continue during the macciation of the rennet, so that the liquid, with additions of water 01 skim milk in place of the portion removed daily for use, ictains its coagulating powei until the appeal anec of new organisms, which overt a putrefactive instead of a fermentative inilueiice, and at this stage it is tin own away and a fresh innceiation made. Solutions of rennet diastase made in this way have no constant power of coagulation ; it is always varying, for at iii^L is seaicely perceptible, becomes well marked after '21 hours, next mci eases to a maximum, mid then dies away. The concentrated solutions known in commeicc as "essence of lennet, ' such as that piepau'd by llansen, of Copenhagen, aie much more | uuitoim, and one gallon ot these sencs to coagulate fiom ten to lifteen thousand gallons of milk. Though the method of picpaiation is kept secret, a similar and vnyjuliu 1 essence of lvnnot can easily Tic made byiapidly washing the stomach ot a young call with plenty of water, distending it, and exposing it to the an for twooi Ihi co months. The paifclcadinginto the intestines is cut away, while the test is rut up into small pieces, macciated toi about three days in six times its weight of -.alt ■Wiilci, th'- quantity of salt being oui'-lwonticlh \i-> weight of tho water. Jn oilier woids it i-, a li\e pci cent solution ot salt, and after the tin oo days, .mother "> pci fint of salt, with 10 per cent of alcohol, is added ; the clear liquid is next pouied oil, the icmaindd' filtered, and what is Idt in the filter is mixed with the liquid liist pouied ofl. It is not absolutely iiccc-Muy that the cm If mliomj stomach is used should live entirely ut the udder. a 5a 5 the rennet diastase pel-i-,1, ts for eight oi ten mouths, being jji .id ually irplaced by pejisinc. Rennet < ssence must always !><> kept in the daik, find in tightly corked full bottles. If the essence is requited di y it i.s obtained by adding lo the liquid about eight times its hulk ot alcohol. This causes the piecipitition of a mass of mucus, which contains all the diastase. After twelve limits the liquid is Jiltcrcd away, and the bolul whicli iciiuiius is diicd at a gentle iiwir. In this toiin it easily resists the action ol the an, and portions can be dissolved in water when required for use. The digestive diastase of cheese is a ferment \ei y siinilai to that of the pancieatic price which plays so important a part in the digestion of foodstuffs after they have left the stomach. In the digestion of milk itself in the animal body, the casein is coagulated by the rennet «liastase in the stomach ol a very young creature, and by the acid gastiic juice in tho stomach of an adult, in thi? form it is useless for pin poses of nutrition, and it cannot be again made soluble until tho acid change has been neutralised by the bile, and then the digestive diastase of the stomach and that of the panel cas produce re-solution. This explanation supports the familiar saying that a wellmatiucd nch cheese is a half-digested food. As to the general theory of chceseniaking, it is lemaiked that milk, even Avhen just diawn, always contains living organisms, <leii\cd from contact with the wider, from the hands of tho milker, or from the vessel which receives the milk. These deprive thcair of its oxygen, and produce forms ot diastase which coagulate the casein. Milk for cheesemaking is either taken just on it comes irom the cow at a temperature of 05 to i)i) degrees, or, if it has cooled, it is again warmed up to this tcmpcratuie, and this favours the increase of the living organisms, which, at the moment of coagulation get hopelessly eutangled in the curd, and necessarily remain with it through all the subsequent operations, to make fine cheese only a little rennet is added ; the coagulation thus takes a long time, while the curd ramaius soft, and retains much whey. It is drained slowly, and as completely as possible, so as to get rid of the milk-sugar. Now it is that the casein ferments develop on, the , .surface, and begin to pioduce diastases, which, littlcby little, penetrate the cheese, and thus a yellowish translucent layer, gradually extending to the centre, takes the place of the \\ lute opaque casein of the curd. The different varieties of cheese arc matured by diastases proceeding from different ferments, aud the manufacturer's skill is directed 'to aY, ways utilising the same ferments-, and preventing the invasion of others, a The useful ferments are generally. present' in much larger quantities than the .others., fOr they impregnate .the air- of ;the factory, the, vessels, and the clothes of 'the workers. Long experience has . taught pon'dijiions most' favourable for'theijr development ; but if there be any defect

, ', i '■ ~? t\ > i t / ; < 3 T ripening, may establish itself. The chcoac-ccllar is then aaicl to be sick, and miking is suspended for a period. ' ' " Certain mouldaalso assist in. the process of ripening. 'J^liey arc, ,alliud to the moulds which accumulate on old ' boots and on pots of jam : but as they can exist only on the surface of the cheese, the manufactuiorn dependent on them are' less cot tain than those in which the moulds aie'iiot encouraged. The fungusniuuld, Fruit ill ia in r/f'timtm, -which is 'so common on old boots and broad, is instrumental in the ripening of Roquefort. I'ontgib.iud, and many othei eheoics. It is cultivated .is near the freezing point as possible, beeansi 1 this temperature hiudcia tlie do\ clopmeilfc of other {jjJoisii"* winch aic nut jcqmicd, As ohce&e h not a favourable medium for its growth, its irieiease N efleofcod by an abundant sowing of mouldy biciul, and to make it spread tlnough the cheese air is admitted by pk-iciug hue hole.-,. In making (Jruyi'TC cheese, the chief difficulty ih expeuenced in heating the curd to 122 degrees, which is done to hasten the sepaiation of the scrum, so that the ijmd may be immediately picssed in a mould. If the gianules arc too laigc, and the heating goes on too rapidly, an impenious coat forms and pi events escape of the berum ; hence, slow heating and constant staring cause the cheese to giain well. The commonest feimcnt in the lipcning of (iiuyi'ro looks under the niieiosoope like an elongated 8 ; it breaks up siigai of milk into several products, amongst them caibonio acid gas', the escape of which loads to the formation of the cavities in the cheese. By over-heat-ing the cuid the cheese gets dry. and refuses to ripen, and, if undercooked, too much gas is disengaged, and the cheese gets filled with largo, holes, and is rendered almost valueless. Between cheeses in which fermentation begins at once, and goes on rapidly, and which should be eaten as soon as 11 pc, and such cheeses as (iruye"re, in which the lipcning is prolonged as much as possible, there may be classed numerous soft and uncooked cheeses like that of Cantal. Two disadvantages characterise Cantal cheeses ; they matin c too 1 apidly, and the ripe condition when attained doea not last. It lias already been roinai ked that the odour and flavour of cheeses are almost entirely due to the products of the decomposition of the casein, and not ot the fat, and it occmrcd to M. l^uclaux that cheese like the Cantal might be prepaied fiom paitiallyskimmed milk, and could fmthcr be moic completely deprived of water in the press. Accordingly he found that the cheese with the odour and flavour of Cantal cheese can be made fiom three quaiteis skimmed milk and one (|iiaitn entire milk, but that the het.t lesults follow tbo employment of cijual <|U.uititie» of each. Cheeses so made sullVr loss altciatiou in six months than the oidiu.ny Cantal in two months, so there can bo no doubt that they posse-> good keeping qualities. — .Live Stutk Joinnnl.

E\'M,s\i> deiivcd last year Coj'2,ooo from the iluty fiom cairiages. Two ladies of tlio China Inland Mission, j\li-5 Brounton and Miss Kerr, have travelled through the province of Human, Western China, wheie no foreign ladies hive e\cr been befoie. An excmpl.uy young lady up town is very paiticular about closing the windowcurtains of her room befoie letiting for the nighb, in order to prevent " the man in the moon" fiom looking in. It is stated that the Si/duey Morning Ifcialil and the Mt Ibomiti Jkjko each paid Archibald Foibes JOO guineas for his aiticle on Gcncial Skobelofr. It was five columns in length, and was written, it is stated, in as many hours. Amiit, called Whimpers is veiy good of its kind, and is also new to many. It is played in this way: a remark is whispeiod by one of the company to another who lias to give the answer aloud ; it should not be a monosyllabic one, but a sentence of some few words, and the remark should in all cases have sonu common into cst for the nssemblod company, The fun consists in guessing m hat the icmark could have been from the answer given. The Pharmaceutical Journal reports the poisoning of a man who had been living on raw, unripe potatoes, and quotes the opinion of an eminent analyst that decided symptoms of poihoning lesult more fre (jiiently than people arc awaic of from any considerable consumption of potatoes, especially when they are \ cry young or vciyold. The poison is said to be found chiefly, if not cntuely, in the skin of the tubci. A mom: the replies to an advertisement of a music committee for a "candidate as organist, music teacher, &c.,'' was the following : " (ientleiuon, — I noticed jour advertisement for an organist and music teacho, cither lady or gentleman, ][a\ r r ing been both for several ycais I offer you my mm vices. 1 ' ]NN T n\\ thatthcic is a public prosecutor in (licit Britain it is no easy to withdiaw from a charge after it has been once brought. At the Brentford Petty Sessions on August 12 a youth of l(i, charged with stealing a purse containing Cl."> JOs, and some ineinoianda, the property of his aunt, was .sentenced to three months' imprisonment with Irird labour, despite the fact that the aunt was deshous of withdrawing the charge, and objected to give e\ idence against the prisoner. A Crmor.s experiment is reported fiom (lienellc by the Figaro. Two doctors have conducted, at the expense of a rich Swedish philanthropist, a series of evpeiimentsupon pigs, lor the purpose of ascertaining the effect of alcohol on the internal organs of drunkards. Fifteen pigs were ticatcd daily upon vaiious descriptions of alcohol and then killed, after the process of alcoholisation had gone on for .some time. Each pig had a different description of liquor. One had uhisky, another brandy, a third absinthe, <iml «o on. When killed, their vital organs were found to be marked with small white spots resembling ulcers. Their flesh was sound, but when gent to market it was seized as unfit for food. A dispute is now going on between the experimenters and the police as so whether the inspector of the market was not mistaken. A stkanok story of "making up a curiosity " is reported in an English paper. It seems that an enterprising tradesman wanted a curiosity to place in his window to draw public attention to his shop and to the exhibits in the window. He thought a long while as to the form it should take, and at List decided upon a Bible with a bullet embedded in it, with an announcement attached that the rolnme was one that had always been carried by a soldier through the war, and upon one occasion had saved its owner's life by acting as a shield against a, well- a i/ned shot. The difficulty was to get the bullet into the book without a hole being pierced through it, but (his w*s overcome at last by introducing some iron plates between the last few pages, and a bullet from a Martini-Henry rifle soon completed the exhibit. Crowds assembled to view the cuiiosity, and iti is said that a local preacher even made it, th.c subject of a thrilling discourse ! ' • Tiik parcel system in sewing machines. — Singer, (band), £5 Is ; bingcr's improved with cover .and all extras, £/>' Ss: Wcrtheim, £4 10s; Home Shuttle, £ijj &ni£ting Machine, £7. >Hawc. White, Dayis, Sec., ul<ynys in stock at D.' s>, Chambers, 70 F< Queon-strpct, Auckland, "Wholesale .nul Retail Sewing Machine Depot; ■■• ' < Where shall I buy my furniture and carpets ? You cannot do better than purchase ' from Garlick and Granwell, %yho have now ft.vqry large assortment of iron bedsteads, varying^la , price from 10s Od to to te^pounds, and keep* in stock bedding i of. all, T£i'zos!i. and' kinds'. Iheir large.factorj^ is completed,, an, d machinery in full swing, enabling them* to turn out'fiirniture quicker and, cheaper than h'tth'crb! G, '&' C.* always haVi ready a'largc variety of drawing- land dtninglroora suites.,' Special < attention is, paid, to bedrpom furniture suitable to, all p lasses. Great \ arioty i q{ carpets, Kidderminster, Briiss'pli.'and'rapesfryi from 2s 6d per yard. Linoleum 'and' oil tlb'th i for nails, rfloms, and •ffices. G. & C. keep all/ kinds'of MancJipitpr gq9ds. £heetings{ calicoes, j > hollands, towelling?, flanneli,, blankets 'dur&iirts.j ctetojlnes, JfamaHt^^ay 'fc&O»Bflfflt 'featalcSgifcs! tent p.o^itj'frooi (t( t Lajiier/iiaf^pJotjLcJ^.enL'abputi/ foj &ariyjwljyind ouri c'aUwguJßlQiSßroaj; /iwrvice,'