homemade coffee extract?
250 g sugar
20 g glucose
50 g water
water as needed
200 g coffee powder
cook sugar, glucose, and water to burnt sugar stage (yes the stage after caramel), add water water to thin out slightly, dissolve the coffee powder. this will keep for a long long time. burnt sugar is no longer sweet, acts as a preservative as burnt sugar discourages bacterial growth. add to milk or water and sugar as needed, perfect for iced coffee preparations.
I make an "extract" that is basically a strong brew, filtered. I don't recall the exact measure, but believe it is 3 Tablespoons of ground coffee, 1/2 cup boiling water.
Place the coffee in a heat resistant container (a Pyrex measuring cup works well for this), pour the boiling water over to 1/2 cup measure. Allow to steep for 5 minutes or so. Strain through a coffee filter into another container (you should get about 1/3 cup *strong* brew. Adjust coffee measure to your need/preference. Refrigerate the remaining in a sealed container. Not sure how long it lasts, as I use mine for coffee ice cream.
I can get the measure I use for you when I get back home on Wednesday.
Or you can make a much less acidic version (though it uses more coffee) by putting a ton of coffee and some water (sorry-- I tend to eyeball things) in a bowl, leave it out at room temperature overnight, and filter it in the morning. It makes GREAT iced coffee, or can be used as you would an extract. It tastes so strong but so smooth. I think I read that it's got 20% if the acidity of hot-brewed coffee that way.