Before meals
Recite:
بِسْمِ اللَّهِ وَعَلَى بَرَكَةِ اللَّهِ
In the name of Allah and with the blessings of Allah I begin
(eating)".
(Mustadrak)
On forgetting to recite Bismillah at the beginning, recite:
بِسْمِ اللَّهِ أَوَّلِهِ وَآخِرِهِ
"In the name of Allah in the beginning and end".
By not reciting Bismillah, Satan has an opportunity of
partake in the food.
(Mishkat)
After Meals
Recite:
الْحَمْدُ لِلَّهِ الَّذِي أَطْعَمَنَا وَسَقَانَا وَجَعَلَنَا مِنَ الْمُسْلِمِينَ
"All praise belongs to Allah, who fed us and quenched our thirst and made us Muslims".
(Ibn Al Sunni)
Alternate dua after meals
الْحَمْدُ لِلَّهِ الَّذِي هُوَ أَشْبَعَنَا وَأَرْوَانَا وَأَنْعَمَ عَلَيْنَا وَأَفْضَلَ
"All praise belongs to Allah who filled our stomachs and
quenched our thirst, rewarded us and gave us plentiful".
Note: If the meals are commenced with the above dua, then
there will be no accountability of the food eaten on the Day
of Qiyamat.
(Hisnul Hasin from Haam)
Alternate dua
اللَّهُمَّ بَارِكْ لَنَا فِيهِ وَأَطْعِمْنَا خَيْرَاً مِنْهُ
"O Allah, You grant us blessings in it and grant us better
than it".
(Tirmidhi)
OR
الْحَمْدُ لِلَّهِ الَّذِي أَطْعَمَنِي هَذَا الطَّعَامَ وَرَزَقَنِيهِ مِنْ غَيْرِ حَوْلٍ مِنِّي وَلَا قُوَّةٍ
"All Praise belongs to Allah who granted this meal, (which I
received) without my power or effort".
All previous sins are forgiven if this dua is recited after
meals.
(Mishkat, Kitabul-li-baas)