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- 26 IUNE-T942AGTURE OF E

- 285 SUGAR CROPS OF 1,-,

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HAWAII WORKING TO HELP WIN WAR 35REVIEW OF THE SUGAR MARKETS 37

VOLUME 37 _—__d NUMSEE 6

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ce BroRIenhino I or Place W C 2Los Angeles Office: 4_ .. es 6th SR.

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resume the salient points of

discussion on rum distillation

will state that: (1) Rum dis

[ation is a process of selective and

- ring extraction. (2) The proc

of fermentation and the post

fermentation treatment of the fer

liented mash bear great influence

n that of distillation, as regards

uality of product. (3) Stills,

jvhether of the continuous or dis

ontinuouk type, should have ample

apacity so that the distillation willpever have to be rushed. (4) The

temperatures of the cooling waterentering and leaving the condenser

should be carefully recorded and aifference of not less than 30°C.hou1d be kept between inlet and

buUet water, provided the temperature of the in]et water is not below30°C. A greater difference must bemaintained when this temperatureiB below 30°C. (5) The distillationmethod to be adopted requires apecial study in each particular case;but in a general way, when qualityof finished product is the main andnost important factor, discontinuous or batch stills should be used.E(6) The economic advantages ofjhe continuous system of distillationrare apparent and undeniable. Forlarge, bulk production, the continupus still may become necessary; buteven in this case the opinion of theWTiter is that a combination of bothSystems should then be used. (7)Foulness of odor in the raw disthilate is unnecessary, undesirable,and entirely eliminable by methodsl1erein outlined. (8) It is important

Rum Specialist; Chief, Division of In.dustrial Chemistry, Experiment Station

the University of Puerto Rico.

to distill rum at the lowest possibleproof compatible with a good quality of raw distillate.

Having thus obtained our rum inthe raw state it becomes necessaryto develop to the utmost the inher

ent characteristics of a good product. This is secured by the processknown as curing or maturing. Herewe wish to state emphatically thatby this process we do not mean converting a bad product into a good,wholesome one. Not by any means.The rum that is bad in its raw statewill continue to remain so, no matter what is done with it, or to it,unless we entirely change and destroy its inherent characteristics asrum, and convert it by many anddubious processes into that wechoose to call rum. Proper rumcuring is not a process to change ortransform, but to develop andfurther enhance the latent qualitiesexisting in the right kind of rawdistillate. Of course, a bad raw distillate or raw rum may be made toimprove, but it will never be converted into a first class beveragethrough the curing process, whetherthe natural or slow or the artificialor rapid curing be employed.

Before starting the curing process,

certain preliminary treatment ofthe raw distillate is almost alwaysnecessary, especially under presentpractices of rum manufacture. Witha high class distillate this treatmentconsists only of diluting to a certainproof before storing in oak barrelsin the case of natural curing, or before proceeding with acceleratedaging in the case of rapid curing.

Vith inferior quality raw distillates(which are the great majority)further treatment more than dilution becomes necessary with either

natural or artificial curing. Thisconsists in most cases in eliminationof foulness of odor, (“hogo,”“tufo”), from the raw distillate.There are two principal ways of accomplishing this purpose, one ofthem essentially chemical in nature,the other essentially physical, whileintervening between these two aremany others, using features of eachof the principal two methods mentioned. The chemical treatments inthe hands of the profane may constitute a source of great danger tothe industry itself and to public

health as well. To illustrate this

point I wish to present comparativeanalyses of two rums. No. 1 represents the diluted raw distillate before any further treatment; whileNo. 2 represents the same raw dis

tillate after it had passed throughchemical treatment with the objectof removing foulness of odor or“hogo”.

A glance at the comparative analytical results will show that: (1) Sam-

JUNE 1942

Manufacture of Hunt

Part IV

Curing and Maturing the Product..

Dilution oj the Distillate, Removal

of Odor, Aging Methods

By Rafael Arroyo, Ch.S., S.E.*

Analytical Results

Sp. Gr. at 20/4C.Alcohol by volumeGrs. alcohol in 100 ml.pH valueT. acidity, nigs. per 100 ml. ab. alcoholAldehydes, nigs. per 100 ml. ab. alcoholEsters, nigs. per 100 ml. ab. alcoholExtraneous impurities

Organoleptic tests

Sample No. 1 Sample No. 2

0.93056 0.9433149.80 42.8739.31 35.86

4.80 5.2017.10 182.753.60 Traces56.60 2.1

None Manganese, Potassium,Ammonium, Iron, Salphates, Chlorides

Foul odor Bad tasteBad taste No odor

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pie No. 1, that had received no treatment, was a sample of a poorly fermented, uncarefu]ly distilled rum;hence its bad taste and foulness ofodor. Nevertheless it was a rum.(2) Sample No. 2, the same originally as No. 1, received a certainchemical treatment aimed at obliteration of bad odor and taste. Butwhat has really happened? Thewriter, who tested these two samples, admits that the “treatment”succeeded in eliminating foul odor;but at the same time no new goododor was developed; the bad tastewas changed in character, but remained, worse than originally. Besides, the poor sample of rum wastransformed into a wholly different,infernal beverage, that was no longer rum, or alcohol, or anything towhich a specific name could be applied. Notice that during the treatment almost 7.0% alcohol by volume was lost; besides practicallycomplete destruction of esters andaldehydes originally present. Thesedestructions of valuable aromaticconstituents were supplemented byan enormous increase in total acidity and by the incorporation intothe rum of extraneous impurities,such as suiphates, chlorides, manganese, iron, potassium. Only qualItative tests were made for the presence of these extraneous, newly incorporated impurities, but the reactions that occurred showed thatappreciable quantities existed ineach case, especially as to suiphates,chlorides, ammonium, and potassium. The inference of the writerwas that potassium, permanganateand sulphuric acid were used to destroy the bad odor through violentoxidation. Then it was found thatthe liquid turned very acrid, coarse,and with a chemical taste, and itwas thought to alleviate this condition by the addition of chloride ofammonium and ammonia water.The final results, as may be seen,were disastrous. We are sorry thattime and space do not allow thepresentation of other cases.

We shall proceed now to discuss thepractice that we consider best andleast harmful to the prestige of the

vigorous, young industry and to thehealth of the consuming public.This consists of first diluting theraw rum to between 100 and 110proof, the final proof to be determined by the length of time intended for aging and size of container to be used, in case slow, natural aging is to be used for obtaining maturity; or according to thenature of the subsequent quick aging process to be practiced. We believe, though, that the range 100-110 proof will take care of mostcases. When a poor distillate is thusdiluted, the foulness of odor becomes much more accentuated andnoticeable. At this point I beg to beexcused for a digression in behalfof the average continental American citizen who may read thesepages. The American public is wellaware of the fact that whiskey, asfirst produced by any of the wellknown processes, is a liquid veryraw, very unpleasant to the taste,and very disagreeable in odor. Thepublic also knows that it takes manya year of natural aging to changethis liquid into a potable product.This is not the case with rum. Rum,properly fermented and distilled,possesses agreeable taste and finebouquet as such. In some instancesit could be used outright. This is thereason why I make reference to thenatural taste and bouquet of a rawdistillate. Moreover, rum will ageor mature to its optimum conditionin but a fraction of the time necessary in the case of whiskey. Thiswe have definitely proved in ourwork, and the fact has been corroborated by European rum experts. When present, this foul odormay be partially or completely removed (according to its origin andnature) through the application ofactivated vegetable deodorizingchars. The amounts of the carbonto use will be determined in eachparticular case. This is a case offoulness of taste and odor removedthrough absorption, and the processis to be preferred in all respects tothe destructive and polluting drastic chemical treatments. Alter theend has been accomplished, the carbon is removed by filtration.

What has happened to the rawtillate during the diluting procEor the diluting and carbon trement processes? First of aD,ideal raw distillate would be cneeding no dilution or treatmentany kind before proceeding wcuring, either slow or natural,accelerated or artificial. Furththese conditions are attainabthrough proper yeast selection, fmentation methods, and post-fementation treatment of. the fmented mash, followed by carefiicontrolled distillation methods. Ipresent technic has not come toyet, Hence, we must treat of Iimportant changes occurring Cing the processes mentioned. Let itake first the effects of dilution athe raw distillate. When a fredistilled rum is diluted, its chezcomposition as well as its plcharacteristics are affected. Thtion of the diluent is felt to aer or lesser extent, in aecorwith: (1) original proof at -

distillation took place; (2)composition of the raw rum;nature of diluent, and mannerapplying it. The deleterious sof the diluent is twofold:and physical. The first consIst.a dissociation of part of thecontent through the hydrolytiction of the added diluent acan acid medium; the second cates by salting out or separscertain essential oils throughand by the lowering effect on Ialcoholic concentration of the rrum through the addition ofdiluent. Among these oils we -

some of the most valuable natu:constituents of a good rum.

When the raw rum has beentilled at a very high proof, say 1175°, a very large amount of dilumust be added to bring down iproof to say 100-110°. Nowmore diluent added, the stroflwill become its hydrolytic effectthe esters of the raw distillate, fi

the stronger will the tendencycome towards separation of thesential oils. Hence, the cautionviously given to distill at the ]o.possible proof compatible with l

30 SUG

ality of distillate. When we con

der the original chemical composii of the raw rum in its relationthe process of dilution, we will

dily see that the higher the totalaity of the raw distillate, theer and more intense will become

e j1ydrolyzing effect of the diluentthe ester content. Also, the high-the original ester conteat, theher will be the amount ofrolysis taking place. This will

hold true as to the content oftial oils in the raw rum.

e nature of, and manner of add-the diluent will also become a

tor of importance during theess of diluting the raw rum.

ere are at least six classes ofuents commonly used (at least ine tropics) for this process: (1)dinary tap water from the cityins; (2) well water; (3) rainter; (4) distilled water; (5)emicafly treated water; (6) alcoHe solutiois in distilled or rainater, previously cured by eitherturat or artificial aging. This lastentioned diluent is the most bene

I and best recommended, but ise one less used on account of theuble of preparing and storingder suitable conditions large

juantities of these weakly alcoholic9lutions. Good practice in rumianufacture should restrain theumber of diluents to but three offle six mentioned above, and theseJhould include: (1) distilled waterjaerated), (2) rain water, and (3)!coholic solutions. When theseJthree diluents are used we still haveLthe inconveniences of ester hydrolyI!Is and essential oil separation,;but in a less degree than when therther above mentioned diluents areed. Of the two plain water dilu

rain water is to be preferred,it contains plenty of air and lacks

e flatness of taste peculiar to dieflled water. Thoroughly aeratedratilled water will also do. Dilutingth aged mixtures of alcohol andjater at about 20% alcohol by volme will be the best method to fol

but as explained before, this1ethod also has its shortcomings,jPeeiaHy for the large producer.

1942

Now, whatever the nature of thediluent in use, the manner in whichit is applied to the raw rum willhave considerable influence in theextent of ester hydrolysis, especially as to the extent of separation ofvaluable essential oils. Cold diluent,suddenly added in bulk, or added ina very short period of time, willprove the most harmful. The opposite condition of applying thediluent, i.e. slightly warm, slowlyand in an atomized form, will provethe least harmful. Once the rawrum has been conveniently diluted,if foulness of odor is observed, itmust be removed in some way, andwe have stated that treatment withactivated deodorizing chars is thebest method to use for this purpose.The amount of char to use is a veryvariable quantity, depending on thenature and extent of the foulness tobe removed. We have found thatthe expense involved in the use ofactivated char will not greatly increase the cost of production.Ordinari]y an expense of from 0.2to 0.5 cents per gallon of treatedrum will suffice. There are, however, two risks in this treatment:(1) The carbon will absorb some ofthe aromatic constituents of therum together with the ill-smellingones; (2) if a thorough and veryefficient filtration is not effectedafter the carbon treatment, some ofthe finest particles of carbon willpass through with the filteringliquid, and will form a deposit lateron when the rum is bottled, especially when the accelerated, or rapidcuring method is employed.

Having prepared our raw distillatefor the curing process, the next stepis to decide on the method by whichthis is to be realized. There are twogeneral systems of curing or maturing employed: slow or natural curing, and accelerated or artificialcuring. The first offers little variation in technic, while the latter isvery variable; as many methods andcombinations of two or more methods exist as there are rectifiers engaged in the business of rum making. We shall treat each system, inthe order mentioned. The slow cur-

ing method is that in which maturing is sought through the action oftime, air, and a good oak barrel,wIth very little added help. In thiscase, the development of the desired properties commonly soughtin a properly matured product, suchas body, good taste, mellowness, anddelicious aroma, will depend on thefollowing factors: (1) inherentcharacteristics of the raw rum; (2)quality of the barrels in which theaging is to take place; (3) size ofthe barrels; (4) pre-treatment towhich these barrels were submittedbefore filling them with raw rum;(5) kind of barrel, charred orplain; (6) temperature and relativehumidity prevalent in the storageroom; (7) length of the agingperiod. In the neft section of thispaper we shall consider, to the extent allowable in a necessarily shortarticle, each of the above mentionedfactors.

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Beet Industry Advisory Committee

A Beet Sugar Processing IndustryAdvisory Committee has beenformed to work with the Sugar Section of the War Production Board.A. E. Bowman, chief of the SugarSection, is the government presiding officer, and the committee members are H. A. Benning, Amalgamated Sugar Company, Ogden,Utah; W. N. Wilds, American Crystal Sugar Company, Denver, Colorado; H. W. McMillen, CentralSugar Company, Decatur, Indiana;3. Stewart, Garden City Company,Garden City, Iansas; Frank A.Kemp, Great Western Sugar Company, Denver; Wiley Blair, Jr.,Holly Sugar Corporation, ColoradoSprings; A. W. Beebe, Lake ShoreSugar Company, Detroit, Michigan;R. E. Lies, Menominee Sugar Company, Green Bay, Wisconsin; W.W. Patterson, Michigan Sugar Company, Saginaw, Michigan; A. A.$chupp, Paulding Sugar company,Paulding, Ohio; Frank J. Beleher,Jr., Sprcckels Sugar Company, SanFrancisco; 3. W. Timpeon, UtahIdaho Sugar Company, Salt LakeCity.

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