Show in the early of last century while stud ing diseases of wine pas beur discovered that it was sufficient to 1 eat bine tor a tew seconds at a of 0 degrees to 60 degrees in order to prevent souring la i e found beer could be like wise ved b heating to 50 de hiees to degrees the applina alon of his process to various articles of food gave 1 to tl term ais pa of milk cons E s in heating it for a short time at a below the boiling boic and hen rap adly chilling it ate object in heating Is the destruct ion of disease producing germs and it the milk ere allowed to it would for a campara long timo at 20 degrees to 37 d gleea th best temperature tor the of such bacteria and tl air poisonous products various ter re agures c nd t have been rec amr eddei for pasteurization ranging from oo 00 degrees to aa degrees and from a few seconds to tv hours the ten te n pasteurized Is accordingly in and shou d bo replaced in coar erce ty a plain babl dic atins the the lime and the date of he nug the two dominant ac tors hai appear to control the tern per aed time of pasteurization are the thermal death points of pal ho genie bacteria and the thermal death points of n alk ferments ahe bacteria should be killed and tie ferments sl demain it may be here noted that con id erable expert mental ind the deter mina ion ot the tl ermal death points of both bacteria ind ferments and that concerning the of milk terr ants nothing is definitely known pa t arize 1 mill then merely meins heated mill ani is not at all synoni with clean milk pure milk or good mil pasteurization cannot a one for mih and cannot preserve the best milk tor any considerable kennth of time pasteurization la used on a lai scale in the cream cries of europe and emerica in den mark and ermany it is much in evi dence and it is eselma cd that 25 per cert of the total dally milk led to he city of new york is pasteur iced in three of he are aeration de ration heating tor times vary ing from 15 minutes to one hour at aj degrees e the milk flows an e pasteurizing ap a atus after which it Is ansly cooka 2 heating for auinger 1 t in sterilized vessels at a deg ees to SO degrees when the vess 1 are scaled and cooled 3 beatin he atin from one quarter hour to ne it go degrees in a tank which the milb pases pa ses a roler r oler into the vessel from which it Is sold A large number of machines ave been constructed for tho qu ck pas of milk in some tha ak is placed in a copper tank pro vided an insulated lacket the tank contains rotating aerna by which the milk is thrown against the heated walls the milk enters at ho bottom an 1 leaves at the top by reg elating the quantity ct milk admitted the of the revolving arma and the amount of tho nielli may be heated desired whatever apparatus be usel it should be under the constant observation of a reliable easy to clean and so abat the entire quantity mil including the loth can bo eq lally heated to tho tempera ture tte thermometer attached shou d be specially tested the the milk passes to cooler which odices tho midi and much as ellk presents tho s range contest of being the most hicl ome of and at tamea a ahe most rols oioi it 1 h moat loffi cul of all to and lua die in pure state in rat it H an ideal medium or the cultivation 01 all clas es of bacate la tho supplied to largo 1 not a sate food 1 due to tha ignorance and of those engaged in the dairy business to the unclean and unhealthy cows used for producing alla to its insufficient cooling to long to unnecessary and ra quent handling to lack ot prope cleansing and sterilization of contain cg ves els and to its frequent asocial on with infectious disease bacteria enter nilla it 1 exposed io the at ahe time of milking this exposure Is great est while perhaps it is impossible to avoid wholly the introduction of bac teria during milking if proper i re cautions be taken the number intro deuced may bs relatively small cac teria reach the milk from the leat udder and body of tie cow from the hands body and clothing of the milk er with the dust from the from particles of excrement or litter which enter the pall and the ill itself the of these bac feua ie as of three ayi es 1 the large group of so called lactic bacteria produces pio duces ac tic acid milk ugar illch acid crecli the i protein of milk causing the well knon burdi ng or souring this always occurs when milk is eai to the air ind kept ai a temperature bove ifa degree f ah 0 o or ilni as a sri in aid Is a as are ilso tho I 1 c their tc barvic by chib tin or c out the e binm fin p bacteria which y roach milk truth the ron ns aia ty lubet methods of tho spoiler P atre faethe 1 ara not hilled by in metho 1 it la olivio la therefore that a d mills putrefactive such as the H or the 11 ficus of I 1 is in i much less protected cond alon than raw milk hotl er group ol 01 organisms product butyric fn also acid change grow best at a per aturo 1 preaching blut of the hu man body and iol spores which resist the of boiling wa ter tor somo time tho products p their crowth i disturb ance in abo tract ct man more of childson chil dion spores ol 01 0 ge mr of ter are not 1 by 3 several microorganisms including tl two mentioned in 1 prod ico putrefactive fermentations alkaline chonge which proceed in milk without indications visible to uw naked eye fht gioi bearing or s are not destroy ed by pasto url bation too frequently ellk comte in contact v ath of specific dis ease e g tuberculosis typhoid fever diphtheria etc for 20 minutes at 60 degrees to 65 degree according to rosenau or 70 degrees to 80 degree for a shorter period according lo 10 jaisen will effectually destroy all euca organisms the length of time during which will keep that is the length of time whick must elapse beto e dent numbers of bacteria develop to produce p changes in itis a function of fac ors temperature and the initial number of bacteria present under conditions the number of bacteria in ellb frashi drawn from a healthy will vary between SOO and 20 per cubic milk cah be produced by commercial which will contain less than 5 teria per cubic ent lmeter on the other ban 1 ca elesely produced th I 1 number may reach sine u consumers consider pasteurized milk as safe it should be required it the process be used that it be heated to a sufficiently high temperature to kill with certainty all disease pro germs pasteurization necessitates a better mode of delivery of ml k but at abst it Is an 1 rather than an ideal method of dealing with rank no trustworthy conclusions can be drawn concerning the effect of pasteurization from the bacterial content of iced milk eold in the market as one does not know the nature of the milk before pasteurization how long it has been kept or the tuie at which it has been kept and in tl la connection it must ever be remen bared that toxic products I 1 by heat are constantly being produced in milk we have method of deter mining whether or not i aste urle 1 milk was damaged befaro it as heat ed a the keeping quality ard bacterial content of briw milk furnish good evidence of its real condition |