Google is now showing detailed nutritional facts for food. Type in the name of a food and Google brings up a side panel to the right of the standard results showing images, Calories per  100gm, levels of fat, cholesterol, carbohydrate, protein and selected vitamins and minerals.

You can bring a specific nutritional fact to the top of the results by including it in the search, for example iron in spinach.

Typing in just the name of a food works in most cases but for some you have to be more specific to pull up the facts. Butter and olive oil are two where you have to include additional terms, for example calories. It also does not have facts for the more unusual foods such as scorzonera and salsify.

The general description is taken from Wikipedia. The sources for the facts include USDA (US Department of Agriculture) so the figures for Daily Values may not be the same as the EU Recommended Daily Allowance.