It has been covered before but not for a while.
In a word, inadequate. When EK negotiate a contract with hotels they negotiate hard and include a big discount on food and beverages. Good, you might think. Wrong. The allowances are based on this discounted rate, which can be up to 50%. Hence, if you want to eat anything outside the hotel you will end up out of pocket. The allowances inside the hotel will cover whatever the cheapest kind of meal is- typically a buffet if there is one. Don't fancy a buffet? Out of pocket again. Finally, room service is often at a lesser discount and the "tray charge" isn't covered. Want to eat in your room (and at some of our arrival and departure times you will have to- the restaurants will be closed)? Out of... well, you get the picture.
As an example, the breakfast allowance for the UK is typically £5. For the USA $10.