More prep work today. Got a few lemons from my aunt's tree (along with oranges for eating, and grapefruit to give to a friend). The lemons were zested and juiced (though not much juice... only 2/3 cup from 5 lemons). Zest is spread out on wax paper on a baking sheet and placed on top of the fridge to dry, so I can infuse oil with it. (Unless fresh zest can be infused into oil? I was planning on doing a hot fast-infusion and using the oil pretty quickly.)
Juice is going to be frozen. I also made a strong tea with DI water to freeze, so it can be used sometime for soap.
Out of pure curiosity, I did a search on the citric acid content of lemons. I found
this abstract from the NIH, and according to them lemons have 1.44g citric acid per oz of juice! I did the math and that means for the bastille recipe I came up with for my most recent batch of soap (40% OO, 35% Soybean, 20% CO, 5% Castor, 500g, 6% SF, 38% water), if I replaced all the water with lemon juice, I'd have 9.65g citric acid! That is nearly double the amount of pure citric acid I added. Now, I know citric acid isn't the only acid in lemon juice (Vit C, aka ascorbic acid, jumps to mind), but it would give a ballpark idea for how to adjust the amount of lye to get the superfat I want.
ETA: Also, I checked the batch I made Monday. STILL seems too soft to unmold. Granted, I used full water and had 80% soft oils (between olive, soy, and castor). I expected a longer time to unmold, but I'm starting to get antsy. How much longer will I have to wait?!