I constantly hear on bird forums that tomatoes are bad to feed to parrots because they are "too acidic." This is just one of many assertions that circulate around as 'fact' but in reality have no basis. Let's take a look at where tomatoes really stand from an acidity perspective.
pH is the most widely used scientific method for ranking acidity. The pH value tells you if something is an acid, a base, or neutral. The ranking goes from 0 - 14, with lower numbers being the most acidic and higher numbers being the least acidic. Zero (0) is acidic, 7 is neutral, and 14 is alkaline. Battery acid would be ranked at 0 (extremely acidic) and liquid drain cleaner would be 14 (extremely alkaline) while something like pure distilled water would be 7 or neutral ... neither acidic nor alkaline.
Fruits like apples, oranges, grapes, grapefruit, and blueberries typically have a range in the 4 - 5 level, but some can also dip down lower into the pH 3 - 4 range. Strawberries and raspberries are in the 3.0 - 3.9 range, and Pomegranate is 2.93 - 3.20. Even blueberries and typically in the 3.12 - 3.33 range.
The acidity of fresh tomatoes can be closely associated with their degree of ripeness. According to the Center for Food Safety and Applied Nutrition at the U.S. Food and Drug Administration (FDA), fresh tomatoes fall into the 4.3 - 4.9 range when it comes to acidity. The more mature and ripe, the lower the acidity, with pH in ripe tomatoes approaching the 4.9 range. For this reason, you want only the ripest ones and steer clear of anything less than fully ripe. Fresh tomatoes are less acidic than canned.
So then, if tomatoes are typically less acidic than strawberries, raspberries, blueberries and pomegranates why do we feed those fruits without concern? As with anything, when you hear comments like this on social media please do yourself a favor and actually look it up and make sure the source is a reputable, reliable one.
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