@CaithnessCC - That sounds like a really thoughtful gift for your sister. I subscribe to several business trade journals in the hospitality field and they all have something to offer.
The best way to decide is to think about what your sister does, and what she has ambitions to do in the future. Some focus on one thing, like wine or recipes. Others would be more useful if she has ambitions to move into management or run her own business one day.