Sugar production, part 1: sugar beets

A couple of years ago we decided that it would be interesting to see if we could produce our own sweeteners.  If nothing else, it would surely help us decrease our sugar consumption if we were to rely just on what we could produce ourselves, which, sugar being unnecessary in the diet and believed by some to be toxic, couldn’t be a bad thing. Before starting, we had to define our goals.  Did we want just the flavor of sugar, or the baking qualities, as well?  something flavorful, or just pure sweetness that could be used without interfering with other flavors? Ideally, I wanted something that could replace table sugar, which is sucrose: a crystalline, neutral-flavored sweetener that would not demand any changes to my dessert-baking habits.  But at the same time we considered backup options: sweet sorghum, honey, concentrated fruit juices, and even, briefly, stevia.  I’ll talk about these all – except maybe not the stevia, which I really disliked – in later posts). The easiest plants from which to isolate sucrose are sugar cane and sugar beets*.  It can also be isolated from some palms (date and coconut), although this process is less common, and from the sap of some trees, most notably sugar maples.  Since our climate is not ideal for sugar cane, palm, or sugar maple production, we started with sugar beets.  We were fortunate to know a couple of USDA sugar beet breeders, who provided seed, explanation of the commercial process, encouragement, and hands-on participation, even though initially they did not have high hopes for our success in a non-commercial production facility. The first step was to grow the beets:

Germination.

Germination.

Maturing sugarbeet plants.

Maturing sugarbeet plants.

These were planted in May, then left over the winter while we were dealing with other crops.  We finally got a chance to harvest and process them in February.  We dug them up, chopped off the tops, then scrubbed the beets and peeled them with a vegetable peeler.  Then we cut them into chunks small enough to feed into a Cuisinart:

Thin-slicing the harvested, skinned beet roots and immediately submerging them in water.

Thin-slicing the roots and immediately submerging them in water.

To avoid oxidation we plunged the slices into boiling water immediately after slicing, then turned the heat off under the water (boiling is apparently detrimental at this stage, causing more of the non-sugar compounds to leach into the liquid and leading to a more difficult separation later).  We did this in batches.  Once all the slices were submerged we let them sit for a couple of hours to allow the sugars to leach out into the water.IMG_3446 Then we drained off the leachate, squeezing the beet slices to express as much sugar water as possible.  In retrospect, a grinder and fruit press would have helped get more liquid out, although this may also bring unwanted compounds along with the extra sugar.  The squeezed beet slices were offered to the chickens, who turned up their beaks at them.  Supposedly cows and sheep love them, though – another reason to get livestock. We then heated the liquid until close to boiling, and added hydrated lime (aka slaked lime, purchased as “cal” from the local Mexican grocery store) dissolved in water.  Unsure of the appropriate proportions, I dissolved about 1/3 cup lime into about 1 cup of the warmed beet water, and poured that back into the rest of the beet liquid (about 16 cups liquid per ~10 lbs of beets).  IMG_3451Then I added about 1 quart of seltzer water, as a way of carbonating the whole mix.  Ideally we would carbonate without adding additional liquid (via a carbonating system), but this was the best we could do at the time.  The lime and seltzer work together to settle out solids. You can see the process happening here: IMG_3488 (the jars have been settling for increasing amounts of time from left to right in the photo). Once the liquid was clear, not cloudy as in this photo, we drained the liquid into a heavy pan and boiled it down until it was about 1/10th the original volume.

IMG_3503

1.5 quarts of concentrated sugarbeet syrup.

IMG_3491

Starting the boil.

We let the jars sit for a few days to allow crystals to start forming.  The second time we did this process, we seeded the liquid with a bit of powdered sugar to encourage crystal formation. Next we used a centrifugal juicer to separate the crystals from the liquid:

IMG_3505

First attempt at crystal separation.

IMG_3536

Second attempt.

This worked great, with one slight problem:  this juicer has a scraper on the top that removes the sugar as it is formed, and dumps it out with the rest of the discards.  This makes sense: it is, after all, a juicer, and is just trying to keep itself clean.  However, it does not make sense for sugar making, as the sugar, once removed, is not recoverable. I have examined many different types of centrifugal juicers, and they all seem to have this design issue. If we were to get serious about home sugarbeet processing we would need to find a juicer that we could modify so that it would actually collect the sugar… At any rate, here is what we got:

IMG_3511

First round.

IMG_3539

Second round.

The yield was about 2 cups of sugar (plus a bunch of very distinctly flavored molasses**) from 10 lbs of beets.  This is not at all representative of what the true yield would be if we had the proper equipment for separation of the crystalline sugar from the molasses, but it did give us an idea of the process.  The most instructive part for me was that we had to buy cal and soda water to get this done.  My feeling is that if I have to go to the store to buy those, I might as well just buy the sugar.  There are ways to make cal at home, but they seem complex and potentially dangerous.  And buying a SodaStream system just to be able to make sugar homestead-style seems ridiculous. One alternative would be to leave out the cal + carbonation step.  This step helps pull impurities out of the liquid, resulting in a final product that has fewer off flavors.  We have not yet tried that; having tasted the molasses and not liked it, I’m not sure if the “flavored” sugar would be worth the effort.  In addition, those impurities can prevent gelling during jam making, so might make the sugar less useful. Another option for simplification of this process is to leave out the juicer separation step.  Rather than physically separating the crystals as we did, some people just leave the boiled liquid at room temperature for several months until the crystals grow large enough that the remaining molasses can simply be filtered away from them. In doing this project, and again in writing this post, I searched for a description of the home extraction process online, and have found very little.  Some examples:

The Southern Minnesota Beet Sugar Cooperative has a thorough description of commercial-scale processing.  They used to have a fantastic video showing the process done on a small scale in a classroom kitchen, but seem to have removed it, unfortunately.

The Ann Arbor Sugar Beet Project 2010 was a great idea, but doesn’t seem to have gone anywhere.

Richter’s seeds has a description that is succinct, but contains a few inaccuracies.

This site has a good description of the process, but they do not go into the final step of separating the sugar from the molasses.

Overall, this was a fun project, but we have not repeated it in subsequent years, and have reverted to buying sugar at the store, toxic or not.  I am fairly okay with this; after all, even Laura Ingalls Wilder‘s family bought sugar from the store, and they were the ultimate homesteaders. * There does not seem to be a consensus on whether these are called “sugar beets” or “sugarbeets,” and apparently the disagreement can get quite heated in certain quarters.  I’ve tried to switch it up here, so as to offend all parties equally. ** The molasses familiar to most home cooks comes from sugar cane processing.  Sugarbeet molasses, although having the same name, is different enough in composition and flavor that it is not normally used for human consumption, and is instead used in animal feeds and other processes.

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