Do not spit out food in your mouth upon hearing the adhan of Fajr

The Prophet ﷺ said: When any of you hears the summons to prayer while he has a vessel in his hand, he should not lay it down till he fulfils his need.  

قَالَ رَسُولُ اللَّهِ ﷺ إِذَا سَمِعَ أَحَدُكُمُ النِّدَاءَ وَالإِنَاءُ عَلَى يَدِهِ فَلاَ يَضَعْهُ حَتَّى يَقْضِيَ حَاجَتَهُ مِنْهُ