A particular brand of Butcher Block sealant/salad bowl sealer, I can't find the link though. I think you want one without added drying agents. You want something that is food safe. Some people do poly.
Like Nacoran said, do some looking around for butcher's block oil. It's sold at Home Depot, Lowes, some online shops. Actually I have an unopened can of this I have no use for. At one point in time I was messing with drilling marine bands for screws and sealing their combs but it's just not my thing. I think mineral oil was another possibility I have a few bottles of that lying around too.
Butcher's Block Oil from IKEA is the best butcher's block oil, if you are going that route. No drying agents, perfectly food safe, and does a good job. ---------- -------------------------------------- View my videos on YouTube!"