DEAR DR. BLONZ: What do you think about the safety of wood versus plastic cutting boards? I heard that wood dissolves bacteria when I was a student, but now I see many people using plastic cutting boards. What is your take? -- R.T., Oakland, Calif.
DEAR R.T.: We first had only wood, but then plastic came on the scene with claims that it was safer. A study conducted at the University of Wisconsin moved the focus back to wood, then the U.S. Department of Agriculture re-examined the issue and their results seemed to vindicate plastic. It is definitely an "up for grabs" issue, but there are some basic principles.
Wood can wick moisture away from contaminant debris inadvertently left on the board, and this can kill microorganisms. While plastic does not have that wicking action, it tends to be easier to clean, and you can toss it in the dishwasher. The take-home message is the importance of cleaning and periodically disinfecting any cutting surface. Allowing a board to dry between uses is also a plus. With wood there is also the need to pay special attention to debris removal so as to prevent any buildup of any blackening mold.
I also suggest separate boards for animal products and non-meat items. It is equally important to clean any cutlery that will be used on multiple items. If you are using towels to wipe off hands or utensils, be sure to use care with those, as well.
DEAR DR. BLONZ: How long after the date on the egg carton are the eggs safe to eat? -- B.B., San Diego
DEAR B.B.: You should take the dating message stamped on an egg carton literally. "Best if used by" will give you a few more days; "Use by" or "Expiration date" describes the recommended end of the line. The eggs don't turn toxic at the stroke of midnight, but they have already been lying around for a number of weeks, so it would definitely be time to use them up or toss them out.
It would be tough to say exactly when things would get dicey for any given carton of eggs, since much depends on the way they were washed, handled and stored as they made their way from the pen to your refrigerator. Then there is the issue of whether your refrigerator did a good job of keeping them at or below 40 degrees F. It is always best to toss them out if you have doubts or concerns. If you do end up using eggs near or just after their time is up, be sure to give them a good high-heat baking or cooking. That's always a good step to help eliminate microorganisms that may have taken up residence.
Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to firstname.lastname@example.org. Due to the volume of mail, personal replies cannot be provided.