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.
Milk for dairy products and as human food is also obtained from camels, donkeys, sheep, yaks and goats. Milk is also sometimes homogenized to prevent the cream from separating from it and leaving a thinner residue. Buttermilk can also refer to fermented milk drinks particularly in countries with a warm climate. Whether buttermilk has been prepared by the traditional churning of milk or cultured, it has a tartness unlike milk due to the high lactic acid content produced by the bacteria during the fermenting process.