It is not permissible to give zakat al-fitr except in the form of what people regard as staple foods.
This is indicated by the report narrated by al-Bukhaari (1510) from Abu Sa‘eed al-Khudri (may Allah be pleased with him) who said: At the time of the Messenger of Allah (blessings and peace of Allah be upon him) on the day of (Eid) al-Fitr, we used to give (as zakat al-fitr) a saa‘ of foodstuff, and our food at that time was barley, raisins, dried yoghurt, and dates.
So they would give a saa‘ of what they ate as their staple food.
Whatever is not regarded as a staple food of the people, it is not permissible to give it as zakat al-fitr.
What is meant by “staple food” is that which people eat as their basic source of nutrition.
It says in al-Mawsoo‘ah al-Fiqhiyyah (6/44): Staple foods include wheat, rice and other basic foods which are suitable to provide nutrition for people’s bodies on an ongoing basis. End quote.
It is well known that sugar and tea – even though people need them – are not things that people consume as a staple food. Based on that, it is not permissible to give them as zakat al-fitr.
If the canned goods are foods that people regard as staple foods, then there is nothing wrong with giving them as zakat al-fitr, such as cans of foul (fava beans), chickpeas, corn, peas, beans and so on.
But it should be noted that cans may contain other things that are added to these foods, so it is essential to pay attention to that when working out weights and measures.
Ibn Qudaamah (may Allah have mercy on him) said:
If what is mixed with it takes up a share of the measure, and is so prevalent that it is regarded as not acceptable, then it is not acceptable (as zakat al-fitr). But if it is not much, then it is permissible to give it (as zakat al-fitr), so long as more than a saa‘ is given to compensate for that share, so that it will be a full saa‘ [of the staple food].
End quote from al-Mughni by Ibn Qudaamah (4/294)
Al-Mirdaawi said: If we say that it is acceptable, even if the amount of the added ingredient is great, more should be given to compensate for that added ingredient [so that there will be a full saa‘ of the staple food in question].
End quote from al-Insaaf 3/130
What al-Mirdaawi said is the correct view, because the aim is to give a saa‘ of food (a staple food). So if a person gives foul in cans, and the foul beans on their own reach the level of a saa‘, there is nothing wrong with that, because he has done what is required of him, which is to give a saa‘ of food. Moreover, these things are added to the foul to keep it from spoiling and enhance the taste, so adding them is not regarded as a fault.
And Allah knows best.