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White Gold

Written by Kerryn Offord

As the gentle winds blow, you look out from the veranda of your plantation house over the acres of sugar cane. What you see isn't fields of cane. What you see is fields of gold. The white gold called sugar, slowly growing to maturity. In Pernambuco in the early seventeenth century, there was nothing that couldn't be bought with enough chests of sugar.

In the 1630's refined sugar sells at the Amsterdam exchange for about 0.8 guilders per pound (NUS$40). That same pound could almost double in price by the time it reaches the consumer in Grantville. At an exchange rate of NUS$50 per guilder, a pound of sugar that could be bought in Grantville for as little as $0.10 before the Ring of Fire could cost NUS$80 post Ring of Fire.

The people of Grantville will have to find substitutes or quickly lose their sweet tooth.

***

Why is sugar so expensive? Well, it's a luxury import. It has to be shipped long distances, and the traders are very protective of their monopoly. For example, dues charged by the Dutch West India Company added about NUS$15.60 to the price of a pound of sugar in Amsterdam [3]. Oh, and of course, there were a few wars going on. Not just in Europe, but also in Brazil where most of the sugar was being grown.

Another reason for the high price was the level of inefficiency in the production. Table 1 shows the relative productivity per acre for the main sources of sugar available to the people of Europe and Grantville. The sorghum entries reflect what might be possible in Grantville with up-time sorghum. Without adequate water (rain or irrigation) plant mass and the amount of sugar recovered can drop to less than a third of the estimates on the table (Appendix 1, table 2, shows the impact of different growing conditions. Hawaii, with plenty of rain fall, produces more than twice as much raw cane per acre as less favored places, but has a similar yield per ton of cane.)

Table 1. Comparison of three potential sources of sugar and the relative per acre plant mass and the expected yield of sugar. Sugar yield is as a percentage of plant mass. Tons are US short tons. The down-time production per acre of sorghum and beet plant mass has been reduced, using the information in appendix 1, table 3 as a guide, to reflect for the impact of the Little Ice Age on the growing season in Thüringia. Sugar cane, being a tropical crop, isn't affected. Note that up-time sugar beets yield is using modern high yield (17%) beets.

Source of sugar	Plant mass (tons/acre)	Sugar Yield (%)	Sugar recovered (pounds/acre)
Sorghum
Down-time: Single vertical mill	5.6	3.2%	360
Down-time: Single horizontal mill	5.6	6.4%	720
Down-time: Multiple horizontal mill	5.6	12.7%	1,420
Up-time: WV maximum	10.5	12.7%	2,670
Sugar Cane
Down-time: Single vertical mill	50	2.4%	2,380
Down-time: Multiple horizontal mill	50	9%	9,000
Up-time state of the art: Upper	50	12.6%	12,600
Up-time state of the art: Lower	50	7%	7,000
Sugar Beet
Down-time: Single vertical mill	13.4	1.0%	270
Down-time: Multiple horizontal mill	13.4	3.6%	1,450
Down-time: Diffusion	13.4	3.8%	1,550
Up-time: Diffusion	25.2	15.8%	7,960

There are five major sources of sugar to consider. They are maple sugar, palm sugar, sorghum sugar, cane sugar, and sugar beet sugar.

Maple Sugar [1]

Maple sugar was harvested in Grantville before the Ring of Fire. Unfortunately, the weather conditions in Thüringia are probably not suitable for production of it. The trees growing in Grantville can be tapped, but the sap is unlikely to produce a suitable product. The climate conditions make a big difference. The right conditions are a deep freeze for some weeks followed by a few weeks of below-freezing night temperatures and above-freezing day temperatures. If there's no hard freeze for weeks, there's no need for the sap to have concentrated sugars at all. If the day temperatures are below freezing, the sap doesn't run. If the night temperatures are above freezing, the sap has all sorts of other things in addition to sugar. When concentrated, those "other things" make the syrup go beyond unpleasant to downright nasty.

In the eighteenth and nineteenth centuries, small sugar maple groves were planted in Scandinavia and Germany in hopes of recreating the delicious syrup. They didn't produce because the climate conditions were wrong. Some areas of Scandinavia are suitable for collecting birch sap, another form of sugar from sap, but only some. It depends on the micro-climate.

Maple sugar will still be available in North America, and could be collected. However I wouldn't recommend an expedition just for maple sugar as we are not sure what impact the Little Ice Age will have on the sap-collecting season. As well, there's still the war to consider.

Normally a tree will yield up to three gallons of juice a day, and would continue flowing for up to six weeks, giving a yield of about four pounds of sugar [1]. Using the old spout and bucket technique of collecting and open evaporation tubs is very labor intensive. Many modern farmers feed sap directly from the spout to a hose that leads to a central collecting tank, which does away with a lot of the labor requirements. In the 1632 universe, however, there is not a lot of suitable hose. Substitutes could be made, although they would probably be more expensive to make and maintain than just doing manual collections.

Palm Sugar [1]

The palms suitable for this sugar are found in the Ganges valley to the north of Calcutta in India. Tapping is similar to maple tapping and produces up to thirty-five pounds of sugar per tree. The tapping season is October to the middle of February. [1] The longer season and warmer climate contributes to the higher yield.

Because of the distances involved, it is unlikely that Palm sugar will be competitive with cane sugar.

Cane Sugar

Sugar cane can be divided into two similar crops, true sugar cane and sorghum. From harvesting to milling, the two types of cane undergo similar treatment. Other than yield, the main difference is that sorghum is usually reduced to syrup while sugar cane is taken all the way to crystallized sugar. The other significant difference is where they can be grown. Sugar cane needs tropical conditions and cannot be grown in Central or Northern Europe. Sorghum can be grown in Grantville in Thüringia.

True Sugar Cane [1, 2, 4, 6, 7, 8, 9]

Sugar cane has already been harvested in North Africa and the southern regions of Europe for a couple of hundred years. By 1631 it has spread to South America, Central America, and several of the Caribbean islands. Sugar cane likes access to lots of water. The best producing areas are tropical with over twenty-six inches of annual rainfall. On average about fifty tons (short ton) of cut cane can be produced per acre. The down-time varieties contain about ten percent of their weight in sugar. In up-time varieties sugar content can range between ten and twenty-two percent of their weight, with fourteen percent being an industry average.

Sugar cane usually comes to maturity after twelve to eighteen months. This is the optimal time for harvesting. Planting or replanting is done using the top joints of growing canes. This is a labor intensive operation, so replanting is kept to a minimum. Normal practice is to allow the cut stump to throw out shoots or "ratoons. "However, ratooning means progressively diminishing yields season by season, so replanting will occur every few years [8]."

Down-time (and in some areas, even today) cane is cut by hand. (Up-time cutters in Florida were expected to cut eight tons every eight hour day. [9]). Once cut the cane is topped to give a regular length of cane. Two man teams then bundle the cut cane into manageable loads and carry the bundles on their shoulders either to the nearest vehicle, or straight to the mill. (An average sugar cane stalk weighs about three pounds [7]). At the mill the cane is stacked until it can be fed into the mill. If the cane was "burnt off"—the field is set alight to clear the field and stems of excess leaves and litter—then it must be milled within sixteen hours of it being cut. If it was cut without the burn-off, then it must be milled within twenty-four hours. After these times the sugar in the cane starts to invert (conversion of the desirable sugar, sucrose, into other sugar forms that won't crystallize.). Sugar cane should also be harvested immediately after the field has been fired, as the heat can start the inversion of the sugars.

Milling is the bottleneck in processing sugar cane. Mills are expensive, so owners try to maximize their use during the harvest. This means they often operated twenty-four hours a day, every day, during the season, which can be six to eight months depending on the local conditions.

Milling crushes the cane to release the sap, or juice. The juice is then heated for at least four hours, or until enough water has evaporated that the juice becomes super saturated and the sugar starts to crystallize.

The sugar at this stage isn't the nice white stuff you get at home. It has to be left to drain the molasses (a non-crystallizing sugar) before it is shipped for refining. Refining is done closer to the market (The Netherlands was a major center for sugar refining, supplying refined sugar to the rest of Europe).

From every one hundred pounds of raw cane going into the mill, the down-time plantation owner would expect to recover two to three pounds of sugar (Modern mill operators would expect to average better than ten pounds of sugar per one hundred pounds of raw cane).

Increasing the extraction yield

The existing down-time sugar mill technology uses three grinding rollers arranged vertically. They are usually powered by draft animals walking around the mill pulling a sweep [2, 4]. (A sweep is like a handle on a grinder. rotating the shaft/handle turns a shaft.) Arranging the rollers horizontally makes feeding the mills easier. Solid iron rollers, rather than the current iron-hooped wooden rollers, would be nice, but changing from smooth rollers to "toothed" rollers will produce a more aggressive crush. The closer together the rollers in the mill are, and the more aggressive the crush, the more juice can be extracted. This should increase the yield to about fifty percent of the available juice per pass.

Horizontal rollers support hopper or chute loading which is not possible with vertical rollers. It is also possible to fill a hopper with small slices of cane and feed them through the horizontal rollers. Cane that has been cut into smaller pieces gives up its juice more readily, offering a few percent more yield. Vertical rollers can not accommodate this improvement. The horizontal arrangement does suffer from power transmission losses due to going from vertical rotation of the sweep to horizontal rotation of the mill. Ideally an engine or water wheel should be used to power the mill and reduce that loss.

The next improvement follows on from something the sorghum farmers know; additional passes through the mill improve total yield. If each pass extracts fifty percent of the juice remaining in the cane or bagasse, then two sets of rollers in series will extract seventy-five percent, and three sets, just under ninety percent. More than three sets of rollers could be used, although diminishing rates of return from each set of rollers might make the cost of installing an extra mill prohibitive. Up-time sugar mills usually have three to five sets of rollers arranged in series, but the energy to power them is cheaper and easier to deliver.

A side benefit of extracting more juice is that the bagasse comes out of the mill sufficiently dry to burn almost immediately. An additional inefficiency of the inferior down-time mills is that bagasse has to be moved to drying areas and then to the evaporation area where it is used as fuel. The new improved model saves in the handling and bagasse can go straight from the mill to the fires of the evaporation kettles.

Yields can be further improved by "washing" the bagasse as it passes from roller set to roller set. This is because, no matter how hard you crush the cane, it will soak up liquid as soon as you take the pressure off. By washing the cane between sets of rollers with hot water, the sugar is washed out of the bagasse. This is worth another three percent of the available sugar content (or sixty pounds of sugar per ton of cane). Washing is much easier to do on the hoppers or chutes used in the horizontal arrangement. In fact, washing of the cane or bagasse will be extremely difficult in the vertically arranged sugar mill.

There are problems with adding water. Unless the water is pure, you risk contaminating the product. And every gallon of water you add is another gallon of water that has to be evaporated. Modern vacuum evaporation can drop energy needs by two thirds, and condensing the water from the evaporators gives safe water for washing the bagasse.

A side benefit of washing the bagasse with hot water is that the waxy coating of the plant can also be recovered. This wax makes up about a tenth of a percent of the mass of the cane, so up to two pounds of wax can be recovered from each ton of cane. As there is almost no additional cost in recovering this wax, the proceeds from its sale can be considered all profit.

With the improvements suggested above, average production rises from the low of two and a half pounds per hundred pounds of raw cane using down-time existing techniques to more than nine pounds using modern crush techniques. It is possible to use diffusion techniques (see sugar beet) on sugar cane, but it isn't usually considered cost effective enough for any but the most productive of sugar canes (Those yielding over seventeen percent sugar by weight).

Sorghum Sugar [1]

Sorghum is a grass similar to sugar cane (An alternative name is Chinese Sugar Cane). High yield sorghum corn (as it is called) is grown in the Grantville area and is known to exist within the Ring of Fire (We have been told that it grows near Mannington by someone who grows it there for the syrup). Up-time, sorghum is usually only reduced to syrup, rather than being further refined to sugar, because the low market price of sugar doesn't justify the additional effort required to produce crystallized sugar. However, things are different down-time. The high market price for sugar makes reducing sorghum syrup to refined sugar an attractive option.

Because of the limited crop land available, farmers near Grantville are unlikely to be growing commercially viable volumes of sorghum. Most likely they are growing the crop for personal consumption (probably no more than an acre). This means they probably mill their own cane using the same mills their grandfather(s) used. These mills are sets of iron rollers powered by an internal combustion engine and yield about half of the possible sugar content and have to be hand fed. This compares favorably with the little better than twenty-five percent yields of the large vertical roller sugar cane mills the down-timers are currently using. Up-timers will know that they can feed the crushed cane (bagasse) through the mill several times to improve the yield. Three passes through the mill can increase the yield to as much as eighty percent, or 240 gallons of syrup (2240 lbs of sugar) per acre. This is only practical as long as the amount of sorghum being handled is small. The typical small farm mill takes one or two stalks at a time, and hand feeding cane, especially the bagasse, is very labor intensive. If sorghum becomes a major crop, then large multi-stage mills will have to be designed and built.

Sorghum is an annual and seeds need to be planted every year. This is important. Up-time sorghum production in the Ring of Fire area would be limited to ...