Here is the full list of all 13 Mealmates achievements.
Played 100 minigames.
Played 1000 minigames.
Perfected all minigames.
Ate 10 Mealmates rated 5 stars.
Collected $10,000.
Held $1000 in a single Party Game.
Bought 20 items in a single Party Game.
Consumed 300 items.
Cooked all recipes.
Found all clothes.
Completed Story Mode.
Completed Explore Mode.
Completed game 100%.