Armed with my recipe success I formulated a plan of attack. Gail's canes were too hard, but her recipe did not mention acetic acid. The soda foamed, maybe the combination of acid and soda would do the trick. I felt that Polkagris might come from a quick solidification of the right foam. I convinced myself that I could find the right balance of acid and soda to do the trick.
The Swedish recipe did not mention the strength of acetic acid, so I decided to use white vinegar. I thought their acetic acid might be strong, so I decided to use a healthy amount of the standard 5% kitchen vinegar. I add this to the mix as it is brought to a boil. Since the Swedish recipe didn't mention corn syrup, I eliminated it.
I decided to hold the sugar and water and vinegar constant and vary the amount of soda used. Since the Swedish recipe was specific on 150 degrees, I decided to hold the temperature constant too. I knew that temperature was key to candy making. In each batch I used 2 cups of sugar, 1 cup of water, and I heated the syrup to 150 degrees Celsius.
The first batch used 4 tablespoons of 5% vinegar and no soda; this would be my control. Pouring the hot candy out on the marble top was exciting. The syrup spreads fast but cools so quickly that it slows to a crawl and never reached the edges of my marble board. I used two knives to fold the candy back on itself several times. This made an extremely hard, almost glass-like candy.
The next batch was the same, but with a tablespoon of soda. I had no idea how much to use, so I went big for the first test. This time the addition of the soda caused the syrup to double its volume. Unfortunately I was unprepared for this foam-up and the entire saucepan got out of control. I had to do some quick thinking to keep the whole thing from making my kitchen an ant haven. The resulting candy was dark, dark brown and smelled horribly. I don't know what chemical reaction happened, but this was way too much soda. I tasted one little bit of the candy and it had a sharp metallic taste to it. The taste stayed with me for hours. I thought I might have poisoned myself, but after a day it faded. Whew.
At this point it was clear to me that I couldn't keep taking random shots at the recipe. I needed a more disciplined and organized approach. From my office I brought some graph paper into the kitchen. The x-axis was labeled with 1/4 teaspoons of soda and the y-axis was tablespoons of vinegar.
The next batch had 1/2 teaspoon of soda and 4 tablespoons of vinegar. This batch was a total flop. The resulting candy was nothing but a mass of goo that almost ran off the sides of the marble.
To bracket the amount of vinegar, my next test was 1 tablespoon vinegar and 1/2 teaspoon soda. This gave a nice candy, but it was a bit too hard. Still, not nearly as hard as the first batch with no soda. This heartened me.
Next I kept the vinegar at 1 tablespoon and pushed the soda out to 1 teaspoon. This was essentially the same result as the last batch. With 1 tablespoon of vinegar, the amount of soda didn't make a big difference.
Hmmm. I decided to follow the perimeter of my test parameters; I kept the soda at 1 tsp and doubled the vinegar to 2 tbsp. Interestingly this gave another all goo product. I was attacking the problem and thought the sweet spot might just be in the middle of my graph!