The food also called prashadam must be cooked with love and served with love and all ingredients used must be in the mode of goodness then eat otherewise do not eat.

All places of worship are for healing and meditation and hence all food must be in the mode of goodness also called satvic food. 

All spiritual masters..avatars.. highly evolved souls will only eat food that is in the mode of goodness ..Like Jesus, Krishna ..Guru Nanak would only eat food that is in the mode of goodness. ..this is to show humanity what to eat but actually in fact they are beyond the need of food. 

Warning: Sikh Temples serve food daily but should be avoided for most is not prepared with love nor served with love considering from my experience most punjabi women are rude when serving showing very little love. Secondly sikh temples because they have sick people in there put too much onions and garlic in the food which are in the mode of passion and ignorance so avoid eating their food for they can stuff it themselves being ignorant idiots.