Food prep finish
The finish and wood to use (and what not to use) on butcherblock tops. August 29, 2001
I need a food prep finish for an oak butcherblock cabinet. What should I use?
Oak is not a good wood for a food preparation area. 1) It is an open cell hardwood with too many places for bacteria to hide. 2) It has a high tannin content, which is not good to eat and tastes bad.
I'd add that oak will stain more easily than other woods. Common stain-producers like wet iron pans and some foods are far more likely to leave difficult-to-remove stains than they would on maple, the more traditional choice of wood for butcherblock.
I've just finished a custom wine and cheese cart. The entire kitchen was in oak, so we made the base in oak and finished the hardrock maple butcherblock top with mineral oil.
The FDA a few years ago did a very complete study of cutting surfaces. It was commonly thought that wood was a very poor surface to cut and prepare food on. Guess what? Of all the common surfaces tested for residue bacteria retention and clean up, wood and specifically oak was rated the least likely to retain harmful bacteria. Maple and red alder were next. Composite materials such as Corian rated lower. While wood has a cellular structure for bacteria to rest in, it also has a pH content that does not allow for bacteria to reside or multiply. Corian and other solid surface materials also have large open pores in which bacteria love to breed. I will take the hardwood cutting blocks that have been used in butcher shops forever.
Half of the above statement is absolutely true. Though some researchers still don't believe it and they have never found the reason, wood and especially oak is antibacterial. However, the pores in oak are clearly visible and will collect and retain food particles and cleaner residue, regardless of cleaning technique. Corian has no pores. It will not accept dye.
The test you referred to was done without washing the surface after the chicken parts were applied and removed. The wood was impressive in killing bacteria. The other surfaces tested were bacteria free after washing. The oak was never chicken residue free.
I am with you in believing that the antibacterial properties of wood are caused by pH or tannin or even the structure of cellulose. Just six months ago I read of another researcher trying to freeze the wood and studying thin slices to find the bacteria that he was sure was lurking there somewhere. Probably a government grant.
Use your oak with mineral oil so it won't go rancid and after using the board, wipe down with a dilute solution of chlorine bleach. Goodbye bacteria.
Give your customers a bottle of mineral oil and tell them to apply some from time to time. They probably won't bother until the surface is all dry-looking and water-spotted, but it puts maintenance responsibility on them.
From the original questioner:
Having already built the top from alternating oak and maple, I might as well give it a try. If I die from it, I'll have someone let y'all know.