hate to break it to you…no airline food is fresh and made to order for each specific flight. All designed to be able to be stored and then catered onboard at whatever time flight is being catered. Yes, it’s only designed to be stored for a maximum of some amount of time, but for the most part, it would be fine to use on a later flight by a few hours, a day, etc. so very well the same food that was refrigerated/frozen for a bit longer than it would have been on the original flight. If it was out at room temperature for more then whatever timeframe is allowed, it would be considered spoiled and couldn’t be used - but unless it’s a very last minute cancelation where flight was already catered or very close to it, doubtful it would affect anything.

used to know an employee who worked for the place that did kosher catering for airlines in YVR, and among the requirements was that it was able to be frozen for 2 (maybe 3?) months, IIRC. So clearly, food can withstand a cancel and be used for next flight.