Applesauce is made by boiling down apples in liquid and then putting them through a food mill to puree. Water or juice are most commonly used as the liquid. After the apples are pureed, sugar or cinnamon can be added to adjust the flavoring as desired.

The pH scale measures how acidic a substance, usually a chemical, food, or body secretion is. The more hydrogen ions a substance has, the more acidic it is and the lower the pH will read on the numbered scale. A pH can range from 0 to 14, with zero being extremely acidic and 14 being extremely alkaline , which is also referred to as "basic" in some cases. Water and saliva have a pH of seven, meaning they are neutral -- neither acidic or alkaline.

Apples, the main ingredient in applesauce, have a pH within the three to four range, depending on the type of apple, e.g., McIntosh, gala, etc. Applesauce generally has a pH of 3.1 to 3.6., again, depending on the types of apples it is made from and the ingredients added during the process. Some people add lemon juice during the process, which has a pH of 2 and can therefore lower the pH of the applesauce ever so slightly. This means that applesauce is an acidic food and not an alkaline food in itself. Its effects on the body, however, are different. Certain acidic foods, like lemons and apples, leave behind minerals as they are broken down in the body. These minerals help get rid of hydrogen ions in the body, helping make the body more alkaline.

Many people believe in eating an "alkaline diet," although this type of diet is not supported by reliable scientific evidence. The basis for following an alkaline diet is in the idea that the Western diet is highly acidic and the body is not able to compensate for this strongly acidic food intake and return its pH to neutral. Therefore, one should be eating more alkaline foods to reverse the effects of the Western diet.

The human body has three systems in place to regulate acid-base balance and only with certain medical conditions do these systems have the possibility of working inadequately. Human blood contains buffers, substances that can neutralize acids and bases. Buffers act as the first line of defense against an uneven balance of acid and base in the body. The lungs are the second line of defense. Carbon dioxide is formed during respiration and transfers into the blood to make buffers, specifically carbonic acid and bicarbonate. If too much carbonic acid builds up, then the lungs respond by increasing respiration and getting rid of the carbon dioxide that forms the carbonic acid. On the other hand, if too much bicarbonate is present, the lungs respond by slowing down the breath and holding on to more carbon dioxide. Lastly, the kidneys regulate acid-base balance through the formation of urine. By choosing which ions to extract and deposit into the urine, they help the body maintain a neutral pH. If the body is too acidic, the urine will be acidic because the kidneys pull out the hydrogen ions and deposit them into the urine to be excreted, leaving a more neutral blood.