This is a traditional Japanese metal grater, still made today. It is used for Ginger and various other reasonably soft items, and grates quite fine. The reverse side features a smaller and much finer grater.
This grater is made of a hard alloy aluminum, which gives me pause as I generally avoid aluminum in cooking equipment that would be exposed to acidic juices. I'd rather use a Microplane grater which is stainless steel, or a Japanese Ceramic Grater - but one sided stainless steel versions similar to this are now also available.
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This type of grater is used especially for Ginger, but also Daikon Radish,
Garlic, small Onions, Carrots, and hard Cheese. It is not tremendously
efficient, but is fine for small amounts. Unlike an aluminum grater, it will
not impart a metallic taste. The photo example is 4 inches diameter (10 cm)
and cost 2022 US $12.99. Versions are available from 3-1/2 inches to 6-1/2
inches.
This is an extremely fine grater made from actual Shark Skin. It is
generally used for grating Wasabe. A very small one (2.16 inches wide) can
be purchased for about 2022 US $26. Artificial ones made of stainless steel
are also available at around $60 for 3.3 inch wide.
Photo by Chris 73 distributed under license Creative Commons
Attribution-ShareAlike v3.0 Unported Attribution required.
This traditional mandolin form cutter, which makes very fine threads on the
side shown, and juliennes a little smaller than Western juliennes on the other
side. This one is over 50 years old and probably not available any more.
This modern unit by Soonear is much more flexible than the traditional
wooden version, as it can cut threads and juliennes to three widths using
changeable blades, and with adjustable thickness. It can also do plain
slices, again with adjustable thickness. Blades of this unit were all very
sharp, not sheet metal but ground from solid. It cost 2022 US $35 on-line.
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