Homemade mint extract

Many years ago, I ordered distillation apparatus from a science supply store with the idea that I would make plant extracts, particularly mint, which I had a lot of. One day followed another; Terry glanced in the box, saw glass, mislabeled it “light parts,” and stashed it in the garage. I didn’t find it again until we were preparing to move here, when I wondered what had happened to it and discovered Terry’s intention to throw it out. It wasn’t cheap, and words were spoken.

Rescued and correctly labeled, we moved it to the new house. I put it carefully in a safe place. Five more years went by.

This year, we had a lot of mint. Hilda and I resolved to distill it. I got the equipment out and put it together. There were some difficulties. First, I had to figure out a heat source. The kit came with a ring stand for a Bunsen burner and a screen flame spreader. I had neither a Bunsen burner nor a gas jet to use it with. I was relieved that the round flask had a flat bottom. Sometimes they are completely round and only have a semblance of stability in a ring stand. Terry had a hot plate in his shop that he used for melting bees wax for grafting. That would solve part of the heat source problem. The other part was the height, and that was related to the condenser.

There were two problems with the condenser. A condenser is a long glass tube with a longer glass tube running through the middle. The outer tube has a nipple at each end for tubing. The lower tube is connected to running water. The upper tube drains the water back into the sink. Cold water running around the outside of the inner glass tube cools the vapor coming from the round flask and causes it to condense and drip out the end. The height problem is that the condenser has to be set up at a particular angle to match the bend glass tube that comes out of the round flask. This requires the round flask and heating source to be considerably above the end of the condenser that drips into the Erlenmeyer flask. For reasons that are not clear to me, both the round flask and the Erlenmeyer had a 500 ml capacity. It not the point of distillation to reduce volume? A 250 ml flask would have been a lot shorter, just saying.

And then there was the issue of the water source. The kitchen faucet was not amenable to having anything attached to it. The laundry sink was threaded on the outside. I had a hose that fit on it. I also found hoses that fit on the condenser nipples in the storeroom; the reason I bought them is lost to history. I only remember having a compelling reason for needing them. Not surprisingly, the faucet hose had a 3/8” internal diameter, and the condenser hoses had a ¼” internal diameter. I would just buy a connector at a home improvement store, and I’d be all set.

It was not to be. The connectors in the plumbing area didn’t go any smaller than ½”. The Big Box worker directed us to the irrigation area. Lord knows I am not short on drip irrigation supplies, but I knew that all my connectors were either ½” or ¼”. Perhaps I could rig something up with what I had on hand.

That was not to be, either. The ¼” connectors were too small for the ¼” hose. It wasn’t my measurement. The hose still had its label, clearly indicating that the ID was ¼”. The drip lines were ¼” outer diameter. I tried fitting the irrigation tube into the other tubes, but it was not satisfactory.

I had to rethink the whole problem. I remember that in a real lab, the hose is connected to a nozzle on the faucet. I did some online research. Nozzles were only available at the home improvement store connected to a vacuum faucet for $169. There must be a cheaper and easier solution. Water balloons. For $4.95, I could get a nozzle for a hose and a bunch of water balloons that I did not need. I took my faucet hose to the outside hose to verify that they were the same diameter. Perfect. Just for fun, the next time I was as work, I looked through the junk drawer for a metal nozzle. I found one, but it was threaded to go on the inside of the faucet, not the outside.

The next time Jane and I were shopping, we found the nozzle/water balloon combo at Jewel for $1.99. 

The nozzle with water balloons

When I got it home and showed it proudly to Terry, he said, “I have a gazillion of those in the shop.”

“Are they small enough?” I asked.

“I think so. They’re metal and they attach to a hose for a Venturi effect” he replied and added for clarity, “and by a gazillion, I mean two.”

When the time came to set up the apparatus, he was unable to find the metal nozzles. He brought me a plastic one that was too large. He also brought me the hot plate, a metal bench, and plywood. He was afraid the hot plate would get too hot for a plastic table. If it burned the plywood, who cared?

Sunday afternoon, Hilda and I started the process by harvesting the mint.

The mint

Hilda starting the mint harvest

While Hilda started stripping the leaves off the stem and washing them while I figured out how to assemble everything by the laundry sink. I had to bring in two brick pavers in the wheelbarrow to elevate the hot plate. Each paver weighed a gazillion pounds, and by gazillion, I mean much more than two. The water balloon nozzle fit the tubing exactly. Here’s what the setup looked like.

The distillation set up

I helped with the leaf preparation until we had enough to fill the food processor bowl. My thought was to extract in alcohol because many aroma volatiles are alcohol soluble and that’s how extracts are generally sold. I had a very old bottle of Everclear from North Dakota, where it is legal to sell it at 95% alcohol. (Illinois Everclear is 70%), leftover from an experiment with cherry cordial that we never ended up drinking. I unscientifically poured some Everclear on the mint straight from the bottle and turned the processor on. It wasn’t enough liquid, so I added an unmeasured amount of water. When it looked right, I transferred the whole mess to the round flask and put it on the flame spreader on the hot plate. We hoped that the flame spreader would even out the heat from the hot plate coil and keep the flask from cracking.

I turned on the faucet and the burner, and we stepped back. I couldn’t think how anything would explode, since the whole thing was open on one end, but you can never be too cautious. Soon the alcohol was boiling and the extract was dripping out of the condenser.

We each put a finger in a drop and tasted it. It was very alcoholic and a little minty. Water boils at a higher temperature than alcohol, but my apparatus did not come with a thermometer so I not could tell by temperature change when all the alcohol had evaporated. I checked the drips periodically and stopped the distillation when I had collected about 100 ml, mostly because I didn’t what the flask to boil dry. It smelled like grass and lighter fluid. Not a good sign, but a drop on a finger had mintiness.

Much to my relief, the round flask rinsed clean. The shape does not lend itself to scrubbing. For the second batch, I measured 100 ml of Everclear and 100 ml of water.  We tried upping the mintiness by steeping the chopped mint in the water and alcohol for 10 minutes before boiling it. We collected about 100 ml of extract as before. I tried adding more water and boiling it longer. I learned that I could tell the difference between boiling alcohol and boiling water by the appearance of the globe above the round flask. Alcohol uniformly covered the inside surface. Water looked steamy. The second boiling produced a cloudy extract that was fairly minty.

We did a third batch with mint that Hilda quick-dried in the microwave. I also prepared a fourth and fifth batch with 1:1 water/Everclear and 3:1 water/Everclear, respectively to steep overnight.

It was time for the taste tests. The kitchen was strewn with mint leaves, stems, puree, and juice from one end to the other. I poured a wee bit of each extract into separate cordial glasses. Hilda took a sip of Extract 1, coughed, and set the glass on the counter. She wanted to warn me, but the alcohol burning all the way down her esophagus prevented her from speaking. I took a sip and coughed. The first taste was as harsh as you can imagine, but the finish was minty. I don’t know if it was all the drops of nearly pure alcohol I had tasted, inhaled alcohol fumes from the distillation, the stricken look on Hilda’s face, or the fact that we had spent the whole afternoon making mouthwash, but I got the giggles and could not stop. We laughed and laughed the whole time we cleaned up the kitchen. We still had a great excess of mint. I put the washed leaves in the dehydrator for tea. The mint that was still on the stem went to Terry for rodent control.

Yesterday morning, I finished the last two batches. The alcohol fumes took me straight to hangover, causing a wicked headache and nausea. Even today, I can’t stand the thought of tasting those last two batches. Hilda tried it coming off the condenser and thought it was mintier. We will need to do a side-by-side comparison sometime. I think controlled dilutions will be in order, perhaps with lime, club soda, and simple syrup.

Regardless of the outcome, it was a lot of fun. We know how to make it work if we are inspired to do more experimenting. We should have tried extracting in water, for example. There might be other herbal things we want to try. It was an adventure!