Lvl 45-50 food vendors?

[Shadygrove]

Food isn't level locked so get the best you can afford/are willing to pay for. ...

It isn't level locked but there is this percentage and cap thing. The best combat food for L 50 will be iL 90 - 130 same as gear.

https://ffxiv.gamerescape.com/wiki/Steamed_Catfish
iL90
Direct Hit Rate +4% (Cap: 24) HQ +5% / Cap: 30
Vitality +4% (Cap: 18) HQ +5% / Cap: 23
Critical Hit +2% (Cap: 10) HQ +2% / Cap: 12
EXP Bonus +3%

https://ffxiv.gamerescape.com/wiki/Ishgardian_Muffin
iL130
Tenacity +4% (Cap: 28) HQ +5% / Cap: 35
Vitality +4% (Cap: 26) HQ +5% / Cap: 33
Direct Hit Rate +2% (Cap: 11) HQ +2% / Cap: 14
EXP Bonus +3%

I have to add that high level CP food is totally broken for low level crafters.