Some Pokemon prefer different flavours, and they are individual with each Pokemon. So 1 of Bidoof may like Mint Pokepuffs while another Bidoof prefers Citrus Pokepuffs. Since you said 5 stars, you probably got the Supreme Spring/Summer/Autumn/Winter Pokepuffs, right? So you probably took a flavour that your Pokemon didn't really like at first then took its favourite flavour later.
Source: Experience and Serebii