“TEACH YOUR OLD CAT
NEW
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Better Protection against chemical attack
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...As We See It
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October 1851
WALTER J. MURPHY, EDITOR
Canada's Destiny no two peoples in the world know more each P about the other than do the peoples of the United States PndCanada, andyet,friendlyas weareandeasyasourcommon ROWLY
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language and onstoma make for intimate understanding, we cannot &ord to w u m e that our knowledge of each other is complete. This was the measage that Victor G. Bartram, head of the vast Shawinigan interests in Canada, brought to the members of the Division of Industrial and Engineering a t a luncheon Chemistry of the AMERICANCHEMICALSOCIETY meeting during the Diamond Jubilee celebration of the Society. When one stops to reflect for a moment or two on Dr. Bartram's comments, the more it becomes evident that generally we are not too familiar with the natural resources and the tremendous growth of the chemical and chemical pmoegs industries in Canada, even though Americans and Canadians boast of the undefended border between the two nations, which for miles and miles is nothing more than an imaginary l i e . Much of the contact between Canadians and Americans is a t a social rather than a business level. It is highly essential that the leaders in science and industry in both countries take the necessary steps to bring about a greater mutual understanding of the resources of the two nations, for in the event of a national emergency Canada can and will play a very important role. Should the international situation deteriorate to the point where World War I11 becomes inevitable, there is little doubt but that steps will be taken by the Canadian and American governmenta to integrate activities in both countries in order to ohtajn the maximum production of war materiel and goods essential to civiliin economy. Strangely enough, comparatively few businessmen in the United Statea realize that Canada in 1951 is very different from the Canada that e n t e d World War I1 and bears almost no resemblance to the Canada that went into World War I in Angust 1914. As Dr. Bartram pointed out, it is the change in character of business activity that is particularly significant. In 1914 Canada was easentdly a producer of primary products, predominantly rnral in Character. Today the industrial potential of Canada is far greater than at any time in ita history, and this growth unquestionably will be accelerated over the next few decades. While agriculture is still the chief single industry of the Canadian people, mining and manufacturing are moving ahead as important sources of national income. Fifty yeam ago, Canada's mineral output amounted to little more than $10,000,000; by 1950 this figure had grown to over $1,000,000,"&a truly remarkable increase which has placed mining next to agriculture among that country's primary industries. Substantial resources in nickel are widely known and, of course, the developments in atomic energy have focused world attention on the deposita of uranium-bearing ores. Canada is rich, however, in many other metals and minerals, upon which considerable industrial manufacturing depends.
The newly discovered iron ore deposits are a blessing to the North American Continent. Over 4OO,OOO,000 tons of proved high-grade ore have been outlined in the vast iron ore drposits of Northeastern Quebec, hbrador, and Newfoundland. Mnch of this ore, according to Dr. Bartram, contains manganese, a most desirable alloying metal and a commodity that is a number one problem child aith us at the present time. We were particularly pleased to hear the tribute paid to Canadian chemists and metallurgiats by Dr. Bartram when he stated: "The r k of the mining industry owes much to thew two groups." Space does not permit us to enumerate the several examples quoted by Ur. Bartram where mining nod production technique* have been vastly improved by chemists, metallurgists, and teehnologista. I t is perfectly obvious, however, that Canadian chemists and engineers have developed very substantial technological advances over the past IO years. The pulp and paprr industry. of course, is one of Canada's most lurrative industries, and the work of chemists and engineers has resulted in brtter methods of bleaching and digestion, in lowcriiig aulfur consumption, and in more efficient rerovery of provesschemicals. One might well expect Dr. Rartram to mention water power in summarizing the natural resources of Canada. Great as has been the development of hydroelectric power by our neighbor to the north, much greater potential resources at the moment remain undeveloped. According to Dr. Bartram, the potential puwcr of the Niagara and the St. Iswrence is probably not equaled by any other water system in the world. Officially it is estimated that the power rivers of Canada will permit a turbine installation of 55,000,000 horse power for recorded resources, of which about one quarter or 12,600,000 is now installed. Whether we think in terms of a future national emergency or view the long-term development of industrial activity on the North American Continent, it becomes increasingly evident that the natural resources and thr industrkl growth of Canada are factors of tremendous importance. A large part of the industrial growth of Canada is in those fields we fmquently describe as chemical and chemical process industries. Obviously, the chen~ical prufcsnions in both countries will develop increased interest in the scientific and terhnologiral advances taking p h e on both sides of the border. Is it not a propitious time for the chemical professions of thr United States and Canada to consider ways and means of developing closer ties and more intimate coopera tion? Some steps have already been taken. During the past year or so several prominent American chemists and chemical engineers have been invited to speak before sectious of the Chemical Institute of Canada. We are of the opinion that sections would Like to many AMERICANCeEmcaL SOCIE~P hear more of the Canadian story presented by the leaders of the Canadian profession. This is one way of encouraging closer cooperation. There must be others. 2179
A Staff-lndustrZyCollaborative Report WILLIAM Q. HULL Assoeiote Editor
W
W. E. KITE AND RICHARD C. AUERBACH Roma Wiine G., Fream, C&f.
in collaboration with
INEMAKING has a l o i i ~and vonvivial history. Since manfirsttilledthesoil, thcprorluctof the fruit ofthevine has been the co11~ortofemperors and kings, the jovial companion of the poor BB well BB of the rich, and the ever popular tlrenie ofpoetry, aong, and story. Juet when m a n firat discovered the grape to be the only fruit capable of naturally preserving itself, without anything bring added to it or taken away, is not known. Tbc firat cultivated vineyard8 are lost in antiquity and there is no definite remrd of the beginning of wine. However, geologists h a w found evidence that grapes were B food of preluacorir man, and as the juice of p-d grapes turns naturally into wine, it is aafe to Bssume that man drank this beverage before the dawn of history. The 6ieroglyphica of ancient Egypt and Bahylon ahow the popularity of wine in that day, and records indicate that winemaking ww practiced in China before 20133 B.C. (16). Approximakly 105 Biblical referencpn have added immeasurably to the colorful traditions associated with winemaking and to the use of wine BB m important pan of the custom8 of many ages. As modern c i v i l i t i o n W M transplanted from the Nrar East into Europe, wine accompanied it. The Greeks were thP first Europeans to cultivate vineyards and they taught the Roman& Alter Caesar's conquest of Gaul, Rome eatablihed wine growing BB an important agricultural pursuit in Western Europe. Since that time, every country in Europe climatically suited lo vine culture has made wine. Between 500 and 1400 A.D. Europ~ became the winemaking contor of thc world. Wine became the univemal mealtime beverage and one of the staple necessities of life in European wine-comuming countries. Many volunied havo been mitten picluring old world mines and winemakirig ( I , 4, 6). This article dcmilwti niodwm winemaking in the western pari of the United State$.
The Frarrriscrur fatlrrrs brought grape rutringa and seeds u-ith them from Mc.vkowhen tlieysrttledinCalilurni..in thelateeighteenth andenrlynincteenth centuries. Vineyard8 wereestablished at tbe early mksionr and, in fact, tho fathcra were the only wine growera in the atate until 1824. While their wines were chieEy fur religious services. talde and medirinal use, and hoepitable entertainment of visiting travelcm, some WBB sold in small lots rurd the quality of California wines became well known. At the present time, wine is commercially mado in 29 of the 48 Rtxtes. In 1949-50,total net production exceeded 100,ooO,ooO d o n a (Tahle 1). California produces approximately YO% of the natioa'a total in tluee to four hundred winCnC8 with capacities ranging from 10,OOO to almost 2O,ooO,Mx) gallons per year. New York'a production ranks sewnd. California's wineries pmdured 125,ooO,ooOgallons of wine in the 1950-Sl wason, an increase of 25% over the year preceding and tho rhird largest output on rewrd. During the years of prohibition, more mine was mado than before thc paseing of the 18th Amendment (IO). However, mont of it WBB made in C C h S of reaideircen in large cities for fanuly use and was generally of very poor quality. Of great importance is the di6erenee in the product of California and the balance of tho ninemaking atatps. With f r w exceptions, Califurnia, because of ita mild climate and auitable soil, W 8 8 early found to be the only state where the I.ilis "inifem or European family of grapes c m be SUCWSsfII!l)' grown. The ~ t a t r ' avine, raiain, and table grapes are mcmbers of tho European family. Moat other American winm are from the Vilis lohruam epccies, which are characterized by their so-called foxy flavor and aroma. The Catawba and Concord grapes are examples of the latter. The wines of these grapes are distinctly &Rerent from those of Europpan g r q m , with spiry flavor8 and aromas entirely their OWL
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TRADE GWSSARY
Acidity
In wine. acidity is the word normally used to indicate the Q U d i t Y of tartness or sharpness to the taste,the p-nce of agreeable fruit acids, an important favorable element in wine quality. Not to be confused with mume.%. dryness. or astringenay. Appetizer wine Wines of de& wine dass which am Uauauy served beforesmesl: indudessherrvsnd vermouth. Aroma That part of ihe f&ranc0 oi wine which originates from the grape8 used; as diatinpiuished from “bou-
Dessert wine
D~~ Fruity
QU&”
Balling or Brix A measure of deneity in degrees which indicates total solids. primarily sugar content. of grape juice; on wine it i the relative s-tnw. Body Consistency. thiclmeea, or substance of wine as o g pmed to laok of body in thin wine; reflects the Quantity of solid matter or extraat in solution in the IiQuid. That part of fragrsnoe of wine which originates Bouquet from the fernentation and aging a8 distinguished from “aroma,” the fragrance of the grape. Brandy A spirit distilled from -e; beverage brandies are 100’ or below in proof; neutral brandies am of 170‘ to 1890 proof Cooperage Bulk wine containersranging in si- from barrels to Isrgetanks. Cuvoe Literally. the contentsof B cask of -e. but usually refers to an aspeciiauy prepared blend of wines. such aa B blend of aW wines before secondary fermentation to produce oham-e.
WINE CHEWISTRY AND TYPES OF WINE
Wine ia the product of the partial or complete fermentation of the juice of sound, ripe grapes. Although various wine experts and interested g o v e m e n t a l agencies have d e h e d it in slightly diEerent term for various and special reworn, all llgree that wine is ementially a fermented alcoholic grape beverage. By law, if made from 8 fruit other than the grape, the wine must be identilied aa to its fruit source. Furthermore, by California law California grape nine may be made only from grapes gmwn in California and the addition of sugar is prohibited. Crushed g r a p and their juice, commonly referred to as “must,” contain sugar, organic acids, tannin. flavoringsubstances, proteina, mineral salts and pectin, various muoiladnous materials, and many other trace substance& Yeasts, bacteria, and fungi,
Generic Lees Must Nutty
Pomace Racking Table wine Varietal
Sweet or partially sweet still wines oontaining approximately 20%alcohol by volume and to which D proportion of brandy haa been added to arrest fermentation. leaving a portion of the original grape ~ u g munfermented. A term indicating that all grape sugar in a wine ha been fermented to alcohol. Having the fragranoe and flavor of the grape: sometimes used to designate B combination of tartness and sweetnew; “grapy.” Wine nsmw based on debita type characteristioa, such as sauterne, Burgundy, and sherry. Sediment deposited by wine during atorage ou aging. Unfermented grape juice, with or without the subm b c e of the crushed grapes. EngliBh term denoting the oharaotsristio pungent flavor of shemy, which the Spanish call “rancio.” Tbe pulp, skins,and seeds of grapes remaining after the juice of newly fermented wine has been d r a m or pressed out. The drawing of wine off its lees or the transfer of wine from one tsnk to another. Wines Oontainiw not over 14% alcohol by volume; usually oonsumed with B m d . Wine named from prinoipsl grew variety from which it is made is mid to have a mrietal mme. It must contain 51% or more of that graw, such as mucatel and Zinfmdel.
some desirable and others undesirable, are also present. Table 111 lists the range8 in composition. Wine is the result of the changes which these substances undergo during fermentation and after pmceasiOg. Organic acids, particularly tartaric, assist in producing mund and healthy wine. &aired range ia between 4 aud 8 parts per thoueand, depending on the type of wine. This concentration ensures a full-tasting wine which stores well, whereas too little acid results in a 5 t taate and short life. In most countries, it ia perrniseible to correct an acid deficiency through the addition of fruit acids such aa citric, malic, or tartaric. Acids slso ensure a better extraction of color, but if present in exwaive amounts render the wine too tart. Tannin ia an eesential component of the wine and is extracted from the skins and seeds of the grape. It aids in the clarilication of wine and produces a more brilliant color. An cxgives aatringency which delays the h a 1 aging of the wine. During the aging of wine, the 5voring substances undergo many c h g e n and to a great extent control the Eavor of the end product. The exact nature of many of these changes is not fully known and much current research is being directed in this field. In fermentation, the natural grape sugar is transformed by action of wine yeaat into carbon dioxide gas and wine alcohol summarized by the reaction:
+
Cdh001+ 2CrHrOH 2C01 Dextrose or levulose Ethyl alcohol Carbon dioxide
Efficimq of Filtration Tested b y Observing Clarity of Wine w i t h a F’dfriCh Photometer with Turbidimeter Attachment
The tramformation is not &B simple ae indicated by this equation, however, for several intermediate reactions are involved. The quantity of alcohol and carbon dioxide formed and the kind and concentration of by-products vary with the strain of yeast and fermentation conditiona. Amerine ( 8 ) has reported the work of other investigators who used champagne wine yeast to obtain 88 actual products of fermentation the compounds tabulated below. Theae are compared with the theoretical products. It ia not implied that these are the only products of fermentation.
INDUSTRIAL A N D ENGINEERING CHEMISTRY
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agent, bentonite is very easy to use. Available in powder or granulated form, it can be readily made up into a smooth suspension and added directly to the wine. Roma adds bentonite in the form of a wine slurry at the rate of 1 to 5 pounds per 1000 gallons of wine, the exact amount depending upon the requirements of the wine being treated. After the bentonite with the suspended matter has settled, which usually takes from 7 to 8 days, the clarified wine is pumped from a valve above the sediment level to filters. The addition of bentonite in no way adversely affects the color, flavor, or bouquet of the wine. Filtration. In the clarification of wine, filtration is a necessary supplement to settling, racking, and fining. The filters remove insoluble tartrates, yeast cells, and coloring matter not removed during earlier processing. Usually one filtration follows fining, one at low temperature follows refrigeration, and an additional filtration immediately precedes bottling. However, if necessary, additional filtrations are made.
A battery of eight plate and frame filter presses constructed of aluminum alloy is used in the Roma winery. Six are 36 by 36 inches in size with a capacity of 6000 to 8000 gallons per hour each, and two are 24 by 24 inches in size with capacities of 3000 to 4000 gallons each (9E). Special chain weave 21-ounce cotton filter cloth is used between the frames. Diatomaceous earth is used as a filter aid and is added continuously to the wine in mixing tanks preceding each filter. These are Type 302 stainless steel tanks, 36 inches in diameter and 36 inches high, equipped with agitating paddles ( 1 2 3 ) . The filter aid is added by an adjustable hopper a t an average rate of 200 pounds per 100,000 gallons of wine. For unusually clear wines, the rate is 150 pounds, for turbid wines, as high as 400 pounds are used. A precoat of asbestos fiber is applied to the filter cloth in the case of polish or final filtrations. Wine is forced through the filter at 35 to 45 pounds per square inch pressure. Ch'iTy of the wine is tested at the discharge end of each filter and checked a t regular intervals with a Zeiss Pulfrich photometer using a turbidimeter attachment. Filter cloth is removed and cleaned of filter aid and other material when necessary, which normally is after every 100,000 gallons or at the end of 24 hours Refrigeration. In many minemaking countries, winter temperatures are sufficiently low to cause precipitation, during aging of the wine, of excess tartrates normally in solution which otherwise might not be removed prior to bottling. In other areas, including California, detartration is slow because of mild temperatures, and refrigeration of the wine to a temperature near its freezing point, resulting in the removal of tartiates in the minimum time, is the general practice. Some wineries store the cooled wine in tanks located in a cold room. Others refrigerate wine by pumping it from a large tank through a tubular refrigerator and returning it to the tank, recirculating until the desired temperature is reached. Roma has six cold storage tanks, each with a capacity of 95,000 gallons. They are made of reinforced concrete and insulation is provided by a 4-inch layer of cork. The principal refrigerating system consists of six 40-ton ammonia refrigerating units which are used in pairs (dE). These are operated by 40-hp. 1800 r.p.m. compressors. Sweet wines are cooled4o 18" F. and dry mines to 24' F. Feed temperature is usually approximately 60" F. and the refrigerating units require 48 hours to cool 95,000 gallons down to the desired temperature. Most wines are held in cold room for 2 weeks and for an additional like period if necessary. They are carefully filtered after refrigeration, a t which time they are ready for pasteurizing if necessary and for additional aging. Various auxiliary refrigerating equipment is used for cooling wine when necessary. Included is a small cold storage room containing eight 5000-gallon holding tanks. Blending. Nature makes no provision for uniformity of different lots of wine of the same type. In order that the color. body, flavor, aroma, and bouquet of any particular type and brand may always be the same, wines of different lots are blended. This is one of the most important cellar operations, and, through blending, wines which vary in acid, body, flavor, color, etc., are balanced to standard specifications.
VOl. 43, No. 10
By the time a particular lot of wine is ready for blending, a mass of data has been accumulated describing its properties. Each storage tank of dessert and table wine has been completely analyzed once a month, and, in addition, table wines have been given a partial analysis n.eelrly. 9 partial analysis includes determination of volatile acids, free sulfur dioxide, total sulfur dioxide, and photometric a,nd microscopic examinations. A complete analysis includes in addit,ion determination of alcohol content, Balling or Brix, total acids, clarity, and, in some wines, iron, copper, and reducing sugar. In addition to the monthly and weekly checks, a complete analysis is also made after every treatment, including each racking, filtering, and fining. As has been true down through the ages, taste tests are still the final and most important factor in determining whether or not a \vine meets all quality requirements. Roma has a staff of longexperienced tasters. The laboratory staff first' makes up small sample blends. If analysis of the blend is satisfactory and tasters agree as to its quality and uniformity (Roma requires unanimous approval of it,s three senior tasters or the blend is rejected), calculated volumes of the various component lots are transferred to a blending tank. After "pumping over" until well xixed, the blend is analyzed and again tasted t,o assure that the blend was made correctly. Heating and Pasteurizing. Some n-ines, particularly muscatel: may contain an excess of albuminoids and proteins which would cause haziness a t 'Ir-arm temperatures if not eliminated. They are removed by heating the wine to 130" to 150" F., a t which temperatures these substances coagulate and precipitate. Pasteurization is used when necessary to kill wine yeast and bacteria. Roma stabilizes its wines against cloudiness at high temperatures by heating the wine to 135' F. and following this treatment with water cooling to 80' F. A multiple-purpose plate and frame wine plasteurizer is used ( I E ) . All parts of the pasteurizer which come in contact with wine are made of Type 304 stainless steel. The unit is also used for flash pasteurizing wine to 160' F. and, through a regenerative system, immediately reducing the temperature to 70' F. Water is used as a heating agent. Wine may also be heated or pasteurized in tank-type pasteurizers equipped with steam heating coils. Roma has three 7000-gallon pasteurizers of this type. They are 7 feet 6 inches in diameter, 18 feet high, made of 3/l~-inchstainless steel plate. Each has three Type 321 stainless steel coils 1 inch in diameter and 70 feet in length. Each unit is equipped with a preheater and heat exchanger. Insulation is provided by a 2-inch layer of 85% magnesia block. Tubular type steam pasteurizers constructed of borosilicate glass and Type 304 stainless steel are also used for wine pasteurization a t Fresno. Storage Tanks. Roma's storage capacity which is used for sboring, aging, and finishing wine totals over 15,000,000 gallons. Tanks include concrete tanks ranging from 5000 to 215,000 gallons, redwood tanks ranging from 1000 to 50,000 gallons, and oak casks ranging from 500 to 9000 gallons each. Concrete tanks are used primarily for storage and processing, whereas the redwood tanks and oak casks are used for aging. During aging, each lot of wine has its own aging characteristic and the point at which it reaches full maturit,y is determined by periodic taste examinations. In general, the aging period may be from 1 to 5 years. Sherry Baking. California sherries are distinguished by a "rancio" or nutty flavor which is the result of heating at low temperatures for long periods of time. The process is called "sherry baking." Roma has six 80,000-gallon concrete sherry baking tanks which are heated by st'eam in l/c-inch Type 302 stainless steel coils. Pale dry sherry is brought to 115' F. and held for 6 months. Regular Bherry is held at 125' F. for 4 months. After baking, sherries are blended for uniformity in quality and again undergo the usual stabilizing processes. Increasing interest has been shown in the production of California sherry by the flor sherry process in recent years. The
INDUSTRIAL AND ENGINEERING CHEMISTRY
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Wine Pasteurization in Rezenerative Unit
cruahed and include chiefly Muscat of Alexandria, Feher Smgos, Palominos, Malagas, and Thompson Seedless, the last two being used principally for brandy and grape concentrates. The principal black grapes ueed are Zinfandel, Petite Sir&, Mission, Grenache, Carignane, and Salvador. Over 95% of the grapes used are bought from the individual growera on both contract and door p u r c k . (They m y be purchssed on the basis of the31 sugar content or by straight tomage.) Grape prices ~ are posted daily. fluctnste considerably during the B ~ B B Oand CRUSHING
Roma's winery is a scene of much activity during the crushing G m p are brought to the winery in 2&km side-dump trucks and trailers and lined up in lanes by Variety. T h e grapes 8888011.
Yamt m a t i o n from Agar Slant to Plant Si- Startem, a Stcpwise Pmadum
are first inspected by the representative of the county department of agriculture, who is the official sugar tester. Four -plea are taken from each 2O-ton load. The variety of grapes is verified, a visual obaervation of the quality is made, and the sugar content of the juice is determined, from which the alcohol content of the fermented product may be predicted. The sugar test, made by meane of a Brix or Balling hydrometer, gives the concentration of a sucrose solution of the m e density ae the juice being tested. The degrees Brix or Balling are approximately double the percentage of alcohol by volume that will result by normal fermentation. Sugar testing techniques as well aa many other wine-teating procedures have been described in detail ( f l ) . Grapes for table wines are generally picked a t a time when their juice tests 20 to 25 degrees Balling and for dessert wines when the juice is 22 to 26 degrees Balling. After accept ance, grapes are weighed on a 60 hy 10 foot motor truck scale which handlee a 2o-ton truck and trailer simultaneously ( f f E ) . The driver then waits hie turn a t the crusher, the cruahing schedule being planned by the fermenting m m supervisor. There are two types of cruahera used in California wineries, the roller and the Italian type. The latter is more common today (7). In the roller t , grapes are c ~ a h e dbetween two fluted horizontal rolls o 8 h ~ or a stainless ateel which turn toward each other. Adjustment in the rolls allows g r a p e to be thoroughly crushed without breaking the seeds or grindiner the stem. pes and stems pass through the rolls into the stem~ ~ % % m s Y t a of a stationary perforated borisontal cylinder h u g h which the apes fall and out the end of which the stemrr are kicked by mpi& revolvingmetal paddle& Roma uees a nonroller-type crusher a t e m r . Trucks move from the scales to the cruaher bins, which are concrete and are approximately 100 feet long and 2 feet wide at the bottom, increasing to 6 feet in width at the top. Moat growers uae sidedump tank trucks which are emptied by a truck m e which tilt3 the truck and allows the grapes to ill into the bin. A continuous bronze drag chain conveyor w i x wood cleats cam* the grapes along the concrete bin to the crusher. A truck and trailer with a loud of 20 tpne of p p e a is normally emptied in about 10 minutes. Microcrystallme WU has been found to he the best coatinn for the conc18tB bins as well aa the walls of concrete ferment& and storm tgnka ( f b h dthoush msny other materiala have-been invesligated (i!?).. As th< a move toward the c m h e r , they pass over a stainleas sk$ 304, 8crcen with I/rineh oerforatians. Freerun iuice "asses t k w h
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INDUSTRIAL AND ENGINEERING CHEMISTRY
distinct bouquet and flavor of sherry made by this process are due to the use of a special group of film-forming yeasts called flor yeasts and through progressive fractional blending during aging. The process has been described in detail (9). Vermouth. There are two types of vermouth, sweet or Italian and dry or French. The vermouth flavor is a result of the addition of numerous aromatic substances to the wine. These include herbs, barks, flowers, roots, leaves, and seeds, most of which are imported from throughout the world, Each producer of vermouth closely guards his formula of flavoring materials used in vermouth making. I n making dry vermouth, Roma uses a selected table wine to which has been added neutral grape brandy as for sherry but t o only approximately 19.5% alcohol. This base is stabilized as for other wines and aged until ready to be used. Roma selects herbs and other flavoring materials from over 50 different botanicals. These are steeped in the wine until the desired flavor is achieved, which normally takes from 5 to 10 days. Redwood tanks, ranging in capacity from 2700 to 10,000 gallons each, are used. The vermouth is filtered from the herbs and is then aged and stabilized for bottling as in other wine processing. Alcohol content in the finished vermouth is 19.0% and residual sugar is 2%. The base wine for sweet vermouth is fermented as described for white dessert wine, except that fermentation is not allowed to proceed as far and a higher sugar content is retained. Xeutral grape brandy is added to give an alcohol content of 19.0%. The finished sweet vermouth contains 18.0% alcohol and a sugar equivalent of 11' Balling. Champagne. Champagne is the most important of the sparkling wines. Its effervescence is due to an excess of carbon dioxide which has been absorbed during a second natural fermentation within closed containers. Choice white table wine is the champagne base. To it are added champagne yeast and sugar, and the mixture, M hich is called the "tiiage," is placed in a closed container and the second fermentation proceeds. BOTTLE PROCESS.In the older or bottle fermentation process, the container is 1 gallon or less, usually a l/i-gallon champagne bottle. The bottles of fermenting champagne are stored horizontally in stacks for several months, at the end of which time fermentation is complete. The clarification or separation of sediment formed during fermentation from the !vine is accomplished by placing the bottles in a rack, neck down, and daily shaking and turning each bottle in a skillful manner until sediment is closely packed upon the cork. The next step is "disgorging," or removing the sediment from the bottle. This is accomplished by quickly freezing the neck of the bottle in brine, releasing the clamp that holds the cork, and permitting the pressure t o force the frozen sediment from the bottle. A "dosage" or sweetening liquor consisting of sugar sirup, grape brandy, and wine is added a t this point. In the case of Brut champagne, the dosage contains little or no sugar. The bottle is then recorked, the cork is nired on, and, after final aging, the champagne is ready for shipment and consumption.
CHARRIAT PROCESS.Making champagne by the bottle fermentation method is tedious and expensive. I n 1907, Eugene Charmat developed a bulk process which bears his name. In the bulk process, the container may be of any size above 1 gallon, however, fermentation is normally carried out in containers ranging from 500 to 1000 gallons. Champagne produced by this process is considered by many t o be of a quality a t least equal to that made by the bottle fermentation process. Roma makes champagne by the Charmat process. The champagne department includes 41 double-jacketed tanks of 1000-gallon capacity each. Type 304 stainless steel is used in the construction of 25 tanks and the balance are Flexlined, or internally coated with a layer of glasslike acid-resisting material. The inner shell is made to withstand a pressure of 150 pounds per square inch and the outer shell contains jackets through which
Vol. 43, No. 10
cold brine or warm water may be circulated for temperature control. -4select table wine especially prepared for champagne is used as a base. To this champagne stock, a quantity of invert sugar sirup, which will give a pressure of between 4 and 5 atmospheres a t 40" F., is added. One atmosphere of pressure requires the presence of 4.3 grams of sugar per liter, and the exact amount of sugar added is determined from this relationship. An active champagne yeast culture approximately 5% of the volume of the tirage is added. The tirage is thoroughly mixed, all valves are closed, and the second natural fermentation begins. During fermentation, the temperature is maintained a t between 62" and 68" F. for approximately 30 days. At the end of this time a dosage of sugar and brandy is added. Champagne is clarified by being cooled t o 24" F. and fitanding for 4 weeks a t this temperature. It is then filtered under isobaric conditions to a second like container. After resting for a t least 30 days, it is bottled isobarically using a special champagne filling machine. Bottles are corked and wired, and are placed in an underground cellar for aging a t 66' to 70" F. Great care is taken in the making of champagne from the selection and crushing of the grapes to the finished product. During the second natural fermentation, temperature and pressure are observed a t periodic intervals. After the third day, decrease in sugar is determined daily. Complete analyses, including taste tests, are made after fermentation is complete, after clarification, and after bottling and aging. BOTTLING AVD SHIPPIVG
Kine is shipped in bottles, barrels, railroad tank cars, and tank truclrs. Approximately 6OY0 of all wine made in the United States is shipped in bulk t o consuming centers, where it is bottled by local branches of the producing company or by wholesalers (19). Savings in shipping cost for transcontinental and other long distance hauls explain the limited bottling at wineriecl, even though bottling at the winery may be more desirable. Since before World War 11, however, bottling at the \vinery has been on the increase in California. At Roma, all wines prior to shipping must pass a temperature stability test and are given a final polish filtration. Shipments are made both in cases and in nine tank cars of 6000- to 8000gallon capacity. Bottle sizes include gallons, half gallons, quarts, fifths, and pints. In the bottling operations, wine comes in contact with only stainless steel (generally Type 302 or 304), borosilicate glass, or special rubber hose. There are six fully automatic bottling lines and two semiautomatic lines having a total capacity of 22,000 cases in an 8-hour shift. Operations performed by machinery are: unscrambling or lining up of bottles dumped from cases, removal of case lint from bottles by air blower, filling, capping, and labeling. Manual operations are: placing of plastic seal on neck of bottles, inspection, and casing. Cases are automatically sealed and after the addition of federal tax stamps and serial number are convryed to the ivarehouse. A11 bottling is subject to careful laboiatory control. Three reference samples from each bottling line lot are kept for 2 years and checked periodically for stability or "shelf life." BRANDY
Brandy is the distilled product of grape wine. Beverage brandy which is made for consumption as such is distilled at below 170' proof, aged in wood, and sold at a proof of 80" to 100". Brandy used to arrest the fermentation in desseit wines is distilled a t above 170" proof. This class includes neutral grape brandy or spirits fruit (grape), distilled between 170" to 190' proof; and neutral spirits fruit (grape) distilled over 190" proof. In the production of grape wines, only brandy or spirits produced from grapes or grape products may.. be used. In a dessert winery approximately one half of the total tonnage of grapes crushed is used for the production of brandy needed in
October 1951
I N D U S T R I A L A N D E N G I N E E El I N G C H E M I S T R Y
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Concrete Storage and Processing Tanks
dessert and appetizer winemaking. The distillery is thus a very important division of such wineries. The distillation of wine and other grape products into brandy has been described in detail
(8.
*
Roma produces both types of brandy. The distillery has four distilling material measuring tanks ranging from 50,000- to 164,000-gallon capacity each, constructed of concrete and lined with microcrystalline wax, There are two double-column continuous stills of copper construction (SE). Each unit consists of a 72-inch beer or stripping column and a 60-inch rectifying column. The beer column is 36 feet high, is made of '/R-inch copper, and has a total of 26 plates. Twenty are perforated plates and six are plates fitted with 51 6-inch Barbet boiling caps. The rectifying column consists of seven sections each 60 inches in height, fitted with 2.5 by 0.625 inch steel rings. There are 46 bubble plates each having 33 6-inch Barbet caps. A dephlegmator, 42 inches in diameter, is fitted with cast bronze tube sheets 0.5 inch in thickness, and has 500 0.75-inch seamless drawn tubes 10 feet in length which are enclosed in a copper shell 0.125 inch in thickness. Condensers are of the same construction as dephlegmators, except that they are of the submerged type. They are 30 inches in diameter, 13.5 feet long, and are encased in a No. 14 gage copper shell. Each contains 300 0.75-inch copper tubes 12 feet in length. A countercurrent beer preheater 20 feet long and containing 20 5-inch copper tubes is provided. In the making of beverage brandy, only the equipment described is used. The product is distilled between 130' and 170' proof. The distilled brandy passes to receiving tanks, where it is reduced to 105' proof with deionized water, then barreled for aging. In addition to the equipment described, an aldehyde column is used in producing spirits for use in making dessert and appetizer wines. The column is of copper construction, has 45 plates, and is 54 inches in diameter. It is heated by an external calandria and is equipped with dephlegmators and condensers. These brandies and spirits are distilled normally a t approximately 186" proof and are used a t this proof.
GRAPE CONCENTRATE
The production of pure grape concentrate, also called pure condensed grape must, is an activity of many wineries. The concentrate is used in the making of very sweet wines, or may be sold as such for other uses. Roma has two vacuum pans equipped with external tubular heat exchangers for making grape concentrate. They are made of Type 304 stainless steel and the combined capacity of the two units is 600 gallons of product per hour (4E, 6E). Steam at 30 pounds per square inch and 275" F. is used in the heat exchangers. Unfermented grape juice a t an average of 23" Balling enters the system a t 110" F. It first passes through the heat exchanger and is then sprayed into the evaporating chamber which is operated a t 120" to 130" F. and a t a vacuum of 28 to 29 inches. Vacuum is provided by barometric condensers. Noncondensed gases are removed by steam ejectors. Juice is concentrated to about 70" to 72' Balling. From the vacuum pans it is pumped to wax-lined concrete storage tanks. The resulting concentrate weighs approximately 11.3 pounds per gallon and contains an average of 8.1 pounds of solids per gallon. It is shipped in drums with unmodified phenolic resin linings or in regular wine tank cars. BY-PRODUCTS
Tartrates. Prior to World War 11, virtually all the crude tartrates used in the United States were imported from foreign wine-producing countries. It was not until these sources were cut off that the California wineries found it economically feasible to recover these products. After the war, when low priced foreign imports again became available, most wineries discontinued recovery. California grapes of vinifera varieties contain 0.8 to 1.2% total tartrate expressed as potassium bitartrate. Some of this precipitates on the walls and floors of fermenting and storage tanks and some during refrigeration. It is a relatively pure grade of potassium bitartrate ranging in purity from 80 to 90%. The bitartrate forms a hard layer attached to the tan!< wslls. It can
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INDUSTRIAL AND ENGINEERING CHEMISTRY
be removed by chipping with hand or air chisels, loosened and blown off by direct steam, or dissolved with a strong alkaline solution. Roma removes it by applying direct steam through a special jet t o the walls of the tank Jvhich causes the cream of tartar to loosen and fall off in large flakes. The bitartrate is sold as crude K H C ~ H ~ O orEargols. Most of the bitartrate is recovered from the lees deposited by the wine during settling and aging. Approximately 20 t o 35% of dried lees is bitartrate. It does not have a market in this form because of its low purity. Roma runs the lees through a classifying centrifuge to increase its purity. This is a continuous separating centrifuge with a capacity of 1500 pounds of dried bitartrate per hour (8E). Potassium bitartrate crystals ranging from 80 to 85% in purity separate out. Discharge from centrifuge, containing from 10 t o 25% moisture, is dried in one of two steam-jacketed batch dryers, 4 feet in diameter and 12 feet long, which use steam at 70 pounds per square inch. The dryers have a capacity of 3000 pounds each and drying time is 5 hours. Product from the dryer, also identified as argols, contains 3 to 4% water or less and is sacked in 100-pound paper bags. The Fresno winery espects to produce 400,000 pounds of this product in the 1951 season. Much of the cream of tartar remains in the pomace after wine is racked and is leached out in the preparation of distilling materials. These tartrates can thus be removed as calcium tartrate either before or after distillation. Roma precipitates the product prior to distillation. Heavy particles in the distilling material are allon-ed to settle out and the clarified liquid is pumped to 210,000-gallon concrete precipitating tanks. Calculated amounts of calcium chloride and lime based on the tartrates present are added to precipitate the tartrates and to adjust the p H to 4.5, since maximum yields of highest purity occur at this point. Reactions are:
+ Ii&,H,O6 + 2H2O IC,CcH40, + CaCI2 --+CaC4H40G+ 2KC1 +
2KHC4Ha06 Ca(OH)z -+- CaC4HdOB
The precipitated calcium tartrate is heavy and settles rapidly. Supernatant liquid is racked off and pumped to the distillery. The calcium tartrate precipitate is resuspended in a-ater and pumped to one of three 8200-gallon redwood tanks. Approximately 200 p.p.m. of sulfur dioxide are added to destroy spoilage organisms. The taitrate is then centrifuged and dried. Calcium tartrate is sold on a tartaric acid basis, inininium yield being specified as 50%. Roma has produced as much as 600,000 pounds of this by-product in a one-year period. Pomace Stock Feed. Roma dehydrates its pomace, after pressing, to a low inoisture content, grinds the dry product, and sells it as a livestock feed. Because of the crude fiber content, which is largely due to the seed hulls, the meal is best used as a supplemental feed, being mixed with molasses and concentrate for cattle.
A rotary, direct-fired gas drum dryer 8 feet in diameter and 60 feet long is used to dry the pomace (IOE). Heat isprovided b y a gas burner and a fan located a t the opposite end draws air through the kiln. Temperature of the flame is automatically controlled t o maintain an exhaust air temperature of about 200' F. Pomace from presses enters the kiln with a moisture content of 50 to 70% and this is reduced to 5 to 6%. Light materials leaving the kiln with exhaust gases are recovered in a cyclone and returned t o a screw conveyor which takes kiln discharge to a disintegrator of the type normally used,in the feed industry ( 7 E ) . Product from the disintegrator is 20-mesh. It is blown t o a collecting cyclone and is sacked directly into SO-pound cloth bags which are then machine sewn. Analysis of the meal is: Protein, %
Fat %
&;de fiber, % Ash (mineral matter), %
12 to 15 6 to 9 21 to 35 5 to 8
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All pomace is disposed of in this manner and large undesirable accumulations common to most wineries have been eliminated. In 1950, the winery produced 1600 tons of grape pomace meal representing approximately 2.5% of the total tonnage of grapes crushed. LlTERATURE CITED
Allen, H. W., "The Wines of France," London, T. Fisher-Unwin, Ltd., 1924. Amerine, hl. A , and Joslyn, hI , University of California, Agricultural Experiment Station, BzrZZ., 639, 29-30 (July 1940). Ibid., Bull. 652 (September 1941). Amerine, M.A., and Theeler, L. B., "Check List of Books and Pamphlets on Grapes and Wine and Related Subjects 1938.48," Berkeley and Los Angeles, Calif., Eniversity of California Press, 1951. Butler, F. H., "Wines and Wine Lands of the World," London, T. Fisher-Unwin, Ltd., 1926. Cruess, W.V., "Principles and Practices of Wine Making," p. 100,2nd ed., New York, SVI Publishing Co., Inc., 1947. Ibid.. pp. 120-1. Ibid., PP. 164-5. Cruess, W. V., University of California, Agricultural Experiment Station, Bull. 710 (October 1948). Cruess, W.V., and HaTrighorst, C. R., Food Inds., 20, 85-92
(April 1948). Cruess. W.V., Joslyn, M. 8.,and Saywell, L. G., "Laboratory Examination of Wines and Other Fermented Fruit Products," New York, AVI Publishing Co., Inc., 1934. Cruess, W. V., Scott, T., Smith, H. B., and Cash, L. M., Fruit Pioducts J., 21, No. 1, 9 (1941). Lothrop, R. E., and Paine, H. S., IXD. ENG.CHEM., 23, 328-32 (1931). Saywell, L. G., Ibid.,26, 379 (April 1934). Schreffler, Carl B., Wines and Vines, 31,No. 6, 29 (1950). Wine Advisory Board, San Francisco, Calif., "The Wine Industry," December 1950. Wine Institute. San Francisco, Calif., Wine Inst. BUZZ. 500, 7 (Sovember 1950). Ibid., 527, 8 (May9, 1961). Ibid., 541 (Aug. 2, 1951). PROCESSING EQUIPMENT
(1E) Cherry-Burrell Corp., Little Falls, ii,Y . , superplate wine pasteurizer. (2E) Cyclops Iron Works, San Francisco, Calif., 800-gallon-perhour wine cooler. (3E) Oscar Krenz, Inc., Berkeley, Calif,, 72-inch split column continuous still. (4E) Oscar Krenz, Inc., side heating element type vacuum pans. (5E) Process Equipment Co., Los Angeles, Calif., vacuum pan. (6E) Rietz Manufacturing Co., Banta Rosa, Calif., pulp disintegrator RD-18-P. (7E) Rietz Manufacturing Co., standard feed disintegrator. (8E) Sharples Corp., Philadelphia, Pa., super-D-cantor classifying centrifuge. (SE) Shriver, T., & Co., Harrison, N. J., plate and frame filter presses, Catalog No. 38., (10E) Standard Steel Co., Los Sngeles, Calif., 60-foot rotary kiln. (11E) Toledo Scale Co,, Toledo, Ohio, motor truck scale No. 60-7032. (12E) Valley Foundry & Machine Works, Fresno, Calif., agitator No. 250. (13E) Valley Foundry & Machine Works, Model No. 240 rotary grape crusher, Catalog No. 47. (14E) Valley Foundry & Machine Works, Model KO. 125 semidisplacement must pump. (l5E) Valley Foundry & Machine Works, 6-inch must valves. (16E) Valley Foundry 8: Machine Works, 15-foot pomace elevators. (1iE) Valley Foundry & Machine Forka, twin screw pomace press Model DS-142. (ISE) \-alley Foundry 8: Machine Works. wine transfer pump Mode No. "-141. RECEIVED August 20, 1981.
