Ed Sisto posted on Thomas Cook's Facebook page earlier this month, sharing his 'alarming' experience on an 11-hour flight from Los Angeles to Manchester.
"I would like to bring your attention to the recent pre-booked vegan meal I received as a 'continental breakfast' on a long haul flight you operated," Sisto wrote.
"It consisted of a box of raisins and a large tub of apple sauce accompanied by a carton of 'Alta Dena Half & Half', which contains milk in the small print. This is extremely alarming, as what would have happened if I had a Dairy allergy?"
"You woke passengers up to give them this, so if somebody is half asleep, they could easily not notice the small print and assume that a meal that is labeled Vegan would not include a carton of milk."
'Absolutely no faith'
Sisto also asked Thomas Cook to provide the ingredients of his previous meal, saying he has 'absolutely no faith' that it would have been vegan.
According to the Mirror, the airline 'appeared to completely misunderstand' the complaint in its online response, where it said: "The apple sauce will no longer be served to avoid this happening again in the future."
Plant Based News has contacted Thomas Cook for comment