Grantville Gazette, Volume 40 (31 page)

Brewing
. Beer is made by fermenting a malted grain (typically wheat or barley), in water flavored with herbs (a variety were used in the seventeenth century, but nowadays hops is standard). The beer yeast converts the sugars in the grain to alcohol, producing carbon dioxide gas as a byproduct. "Top-fermented" beers are produced in open vessels, at around 20
^o
C (68
^o
F), and stored for a few days or at most weeks at normal cellar temperatures. (Cannavan).

Even with top-brewed beers, temperature control would be desirable. "When the weather was hot and sunny it was possible that fermentation would run out of control." (Sambrook 155). "The first recorded use of a thermometer in a brewery was in 1758. . . ." (Blocker 94).

Conventional wisdom is that before refrigeration, brewing was seasonal, avoiding summers. However, the reality is more complex, at least for top-fermented beers. In Derbyshire, England, at Calke Abbey, during 1834, ale was produced only October through May. Beer was produced throughout the year, but summer brews were smaller and less frequent. Whereas at Lilleshall and Trentham in 1646
–
7, the peak production was June for strong beer and September for weak. (Sambrook, 155ff).

Lager yeast (
S. pastorianus
) flocculate to form large dense clumps that settle to the bottom of the vessel, and is active at colder temperatures than are the top-fermented ale yeasts (S. cerevisiae). They have an optimal growth temperature of about 28
^o
C, a maximum growth temperature of about 34
^o
C, and a minimum growth temperature of about 7
^o
C. They are traditionally employed at 7
–
15
^o
C in order to "develop specific flavor characteristics."

In contrast, ale yeast forms loose clumps that trap carbon dioxide, and thus rise to the top of the tank. Ale yeast have an optimum growth temperature that is above 30
^o
C, and a maximum growth temperature of 37.5
–
40
^o
C. Most will not grow below 15
^o
C. They are usually used at 18
–
25
^o
C. (Essinger 123; Robert 349
–
50).

Supposedly around 1420, brewers in the Bavarian Alps "discovered that beer lost its natural cloudy appearance when stored in mountain caves. . . ." This discovery gave rise to the lager style, "bottom-fermented" beers, which are fermented at about 8
^o
C (46
^o
F), "with as little air-contact as possible and cold-stored for as long as possible (six months was once considered the minimum . . .)." (Cannavan).

With Alpine caves at their disposal, these Bavarian brewers didn't have to worry about refrigeration. Their lager was winter-brewed and winter-stored, however.

When lager became popular outside of Bavaria in the late 1830s, the brewers had to harvest or buy natural ice from lakes or rivers and store it. (Blocker 94). In 1880s America, the brewers were the biggest customers of the natural ice companies, and sometimes cut and stored their own ice. Dissatisfaction with the seasonality of the natural ice supply, and the occasional ice crop failure, led them to be among the first adopters of artificial refrigeration (see "Competition" section).

Frozen Desserts
. A dessert, by definition, is sweet, and therefore contains some kind of sugar. The source of the sugar could be fruit juice, wine, honey, sugarcane, sorghum or sugar beet.

Frozen desserts include sherbets, water ice, ice cream, ice milk, and sorbets. FDA defines a sherbet as a food produced by freezing, while stirring, a mixture of a fruit juice (or certain other sources of flavor and sweetness) and dairy ingredients, the resulting milkfat content being 1
–
2 percent. (37 CFR 135.140). A "water ice" is similar except that it contains no dairy ingredient except egg white. (135.160). And "ice cream" is similar except that it contains at least 10 percent milkfat. (135.110). In-between sherbets and ice creams, we have low-fat ice cream, also known as ice milk. The term "sorbet" doesn't have a legal definition, but it's often used as equivalent to "water ice." The term "milk ice" is sometimes used to cover all the frozen desserts in which milk is incorporated.

The use of the terms "sorbet," "sherbet," and "ice cream" in historical literature is quite different than the modern usage. For example, in sixteenth-century France, a sorbet was a beverage, a sweetened fruit juice diluted with water. (David 46). A Turkish sherbet of the same period might be ice-diluted, and a European copy might be ice-cooled, but that doesn't mean that either was
frozen
. Likewise, you cannot assume that a product called "ice cream" was one in the modern sense unless you actually can read the recipe and see that milk was used.

There are plenty of entertaining legends about the origin of ice cream (milk ice). There is some evidence of frozen milk products in early China, but it didn't seem to have much impact on seventeenth-century Chinese culinary practice, let alone what Europeans ate. I think it unlikely that the Arabs—even the "Caliph of Baghdad"—ate ice cream, although they certainly enjoyed flavored and sweetened water ices. There's no doubt that Italy was the first European country to enjoy ice cream, sometime after chemical freezing methods (see below) became known there, and it's possible that milk ice was available there before the Ring of Fire (RoF). Ice cream was first served in Britain in 1671, at WindsorCastle (Durant 172). Ice cream reached France sometime before it reached Britain.

Non-Culinary Uses of Refrigeration

One of the earliest non-culinary uses of ice (and ice water) was to bring relief to fever victims. (Visser 290). This prospect, in fact, was the key selling point that permitted Frederick Tudor to obtain a monopoly for the sale of ice to the British Caribbean (Weightman 46). Ice could also be used to minimize swelling and inflammation.

The main limitation on the use of natural ice for non-culinary refrigeration is that natural ice alone can only bring temperatures down to the freezing point of water; it cannot achieve colder temperatures as can a mechanical system. However, one can use chemical refrigeration (freezing mixtures) as discussed in a later section to achieve moderate freezing.

In the OTL, air conditioning of homes, workplaces and vehicles made hot summers more tolerable. It would require enormous quantities of ice, but conceivably natural ice could be used to cool air in ventilation systems. This would be somewhat similar to its use in the late-nineteenth and early-twentieth centuries on refrigerated rail cars. It would probably only be practical, if at all, in municipalities with excellent rail or water connections.

Likewise, ice can be used to cool chemical reactors. This is actually still done, on a small scale; a laboratory might use an ice bath to slow down a reaction, to reduce the vapor pressure of a volatile substance, to favor e. Salts can be added to the ice bath to achieve colder temperatures. Ice might also prove useful in munitions plants, to reduce the temperatures at which the explosives are made and stored.

Refrigeration, possibly with natural ice, might also be used to remove (by condensation) moisture from the compressed air used by a blast furnace.

At least in the Far North, ice blocks can be used in construction, as evidenced by the Inuit igloos. Russia had the first known "palace" made of blocks of ice, constructed for Anna Ivanovna in 1739
–
40 (Wikipedia/Ice Palace). For serious construction, we will want to take a look at some form of pykrete. It's uncertain whether it's in Grantville literature, but there are certainly books on WW II in town, and one may have passing mention to the proposal (Project Habbakuk) to construct an aircraft carrier using ice reinforced with wood pulp, with the ice integrity maintained by artificially refrigerated brine pipes. Pykrete strength was about 7600 psi, half that of 1940s concrete. (Wikipedia/Pykrete). Additional strength could be achieved with better reinforcement (see my polymers and composites article), and insulation could be added, but it is probably wise to limit even a super-pykrete to the higher latitudes.

Trade in Ice and Snow Before RoF

The snow and ice trade is an ancient one. The Bible speaks of the refreshing nature of the "cold of snow in the time of harvest." (Proverbs 25:8, 13). Snow certainly wouldn't have been lying on the ground of Judea in the fall, so this was snow saved from the previous winter.

Generally speaking, those southerners, whether in southern Europe or in Asia, who had the advantage of living reasonably close to mountains that were snow-capped in winter, could enjoy chilled beverages in summer—if they could afford to pay for this privilege.

China
. A poem written around 1100 BC states, "In the days of the second month, they hew out the ice. . . in the third month, they convey it to the ice houses which they open in those of the fourth. . . ." (David 228). I don't have any specific information about Chinese ice harvests in the seventeenth century, but in the eighteenth century, the British East India Company became aware that Chinese fishermen and fish merchants had above-ground ice houses and used ice to preserve fish. The ice, in turn, came from rice paddies deliberately flooded during the winter. (229ff). Ice could also be heaped outdoors and covered with several feet of clay. (243).

India
. The ice used by the Mughal emperors could be manufactured chemically (see later section), or harvested from natural sources. Beginning in 1586, natural ice was brought to Lahore, the new Mughal capital, from the mountains, about 100 miles away. It could be transported by barge, carriage or bearers. The
Ain-i-Akbari
reports, "all ranks use ice in summer, the nobles use it throughout the year" (Mubarak 56). It was about five times expensive during the monsoon heat as in winter.

The price in Akbar's time was as low as five copper dams (from which coin we reportedly get the expression, "I don't give a dam(n)") per ser (637.74 grams). At the time there were 40 dams to the rupee, so that's one-eighth rupee. In 1873 Calcutta, American ice sold for the same price! (Mubarak 56).

EB11/Ice provides information about nineteenth-century Indian practice (but I would suspect that the practice was already centuries old): "In the upper provinces of India water is made to freeze during cold clear nights by leaving it overnight in porous vessels, or in bottles which are enwrapped in moistened cloth. The water then freezes in virtue of the cold produced by its own evaporation or by the drying of the moistened wrapper. In Bengal the natives resort to a still more elaborate forcing of the conditions. Pits are dug about 2 ft. deep and filled three-quarters full with dry straw, on which are set flat porous pans containing the water to be frozen. Exposed overnight to a cool dry gentle wind from the north-west, the water evaporates at the expense of its own heat, and the consequent cooling takes place with sufficient rapidity to overbalance the slow influx of heat from above through the cooled dense air or from below through the badly conducting straw."

This was an extraordinarily labor-intensive process—two thousand laborers might hope to collect 25
–
30 tons in one night (Wightman 143)—but beggars couldn't be choosers.

Persian Empire
. In mid-fifth century AD, a member of the Chinese diplomatic mission observed that in Ctesiphon (near modern Baghdad), "families keep ice in their houses." (David 199). Persian methods of producing and storing ice varied from region to region. In some places it was practical to bring snow and ice down from the mountains, and in others they had to make it locally.

In 1620, according to the Marquis Pietro della Valle, ice was made in Izfahan by creating conditions in which water could freeze outside. They dug a long trench and built a three-sided shade wall around it, so the trench was exposed only to the north. The wall protected the trench from the wind as well as the sun. Beyond the trench, in the plain to the north, they dig many small, shallow channels. They flood the channels, which froze over at night. In the morning, transferred the ice from the channels to the trench. Water was poured over the old ice in the trench so the new ice would fuse to it. (David 191ff). The trenches were covered with reeds during the day. (208) Come summer, the ice was broken with pickaxes, and sold in shops or by street vendors. The practice continued throughout the seventeenth century, as attested to by the reports of Jean de Thevenot (1650s
–
60s) and John Chardin (1670s).

Ice was cheap. Chardin notes that ice was sold by the donkey load, for effectively two deniers a pound. If a French denier had the same value as a Dutch denier—1/120 of a guilder—its purchasing power was probably about a third of a dollar in USE currency. Jean-Baptiste Tavernier, after returning from Persia in 1670, stated that there were charities, funded by bequests, that sent workers into the street with ice and water to provide it free to anyone who asked for it, and Chardin said that the wealthy would have ice water placed outside their homes for the convenience of passers-by. (212).

Despite the availability of this manufactured ice, some consumers preferred mountain snow for their drinks, and that too was available at the bazaar. Doctor Fryer reported that in 1676, even the poor would spend part of their money on snow.