For Santoku Knives
Do santoku knives need a special sharpener?
That depends on the kind of santoku knife you own.
Real Japanese santoku knives have thin, straight-bottomed blades that are designed for chopping and mincing. They might have a bevel on just one edge, said to create more precise cutting. They traditionally are sharpened on a whetstone.
Santoku-type or hybrid knives have a distinct, rounded-edge profile and, often, a line of scallops that are supposed to keep food from sticking to the blade. Their blades may be slightly curved on the bottom. They usually are thinner than standard kitchen knives, which means that the angle created by many home-sharpening systems might not provide proper treatment. Santoku-type knives often have a two-sided bevel, so a V-shaped sharpening system can be used.
Wusthof-Trident of America created its Santoku Knife-Life Sharpener because its version of a santoku knife is the best-selling knife in its company's history (and falls into the "santoku-type" category). It sharpens at a much finer angle -- 11 degrees per side -- than standard knife sharpeners.
We put Wusthof's hand-held, two-step sharpener ($19.95, available at Crate and Barrel) through the same dulling/cutting tests as we did the other knives we tested (see Tool Test results, above).
Five slow swipes in one direction through the coarse side, then five more on the fine ceramic side created visible metal shavings on the blade of a dulled Rachael Ray/Furi santoku-type knife. The sharpened edge did not cut paper well but did an adequate job of cutting through tomato skin. The short sharpening rods could wear out quickly with heavy use.
-- Bonnie S. Benwick and Joe Yonan