Photosynthetic cells contain chlorophyll and other light-sensitive pigments that capture solar energy. In the presence of carbon dioxide, such cells are able to convert this solar energy into energy-rich organic molecules, such as glucose.
Yes, you can add a little lemon juice or vinegar to the goat's milk to make it into a buttermilk or kefir. This will lower the pH of the milk, and allow it to release the CO2 stored in the sodium bicarbonate (baking soda), causing the bread to rise. Goat's milk generally has less fat and more vitamins.
Once mixed add the rest of the cup of milk. Cream of tartar is an acid and will simulate the acidic environment of buttermilk in a pinch. Stir 1/4 cup almond milk into 3/4 cup almond milk yogurt. Add a splash (about 1/2 teaspoon) vinegar to the mixture and stir well. Soy milk and yogurt can also be substituted for the almond milk products.