Introduction to the M

Introduction to the M-Curve Tamper
Tampers are tools essential for baristas.
Take your extraction to the next level with the M-Curve
Tamper proprietarily designed by Maruyama Coffee.
Channels and Espresso Quality
Left: Flat tamper (Variations in
color reveal that hot water did not
reach some of the coffee.)
Right: M-Curve Tamper (An even
color reveals a thorough extraction
was achieved.)
Coffee cakes are the coffee dregs left after extraction of espresso. Channels are the
depressions left in these cakes, common in the area next to the rim of the filter.
The formation of channels represents the exit location of hot water
on the surface of the cake touching the filter. They are considered
to be one of the indicators of poor quality espresso, as they
indicate the failure to push hot water through the entire cake,
resulting in watery espresso.
Hot water should be passed through the coffee evenly but
tamping the coffee multiple times takes too long and the resulting
stuffed filter would not likely produce good cup quality either.
Considering these issues, Maruyama Coffee focused on the shape of the tamper to try and
prevent this problem.
Regular Tampers
There are, generally speaking, two types of tampers on the market.
1. Flat
Merit Tamper base is flat making it easy to feel parallel when tamping.
Demerit If tamping is slanted, hot water passes in a slanted direction resulting
in an uneven extraction.
2. Convex
Merit Even if tamping is slanted, hot water will flow for the most part through
the middle of the filter.
Demerit It is difficult to sense slanting.
Development of a Tamper that Prevents
Channel Formation: M-Curve Tamper
↓
Maruyama Coffee’s proprietarily developed
tamper, M-Curve Tamper, has the benefit of both
flat and curved tampers while also being designed
to prevent channel formation.
This tamper is composed of three different
contact faces: the flat face of traditional tampers,
a curved face, and the guard face, an important
design point.
1. Flat Face
Easy to tell parallel when tamping
2. Curved Face
Even if the coffee is tamped at a slant, hot water
pools in the middle of the puck.
3. Guard Face
Prevents channel formation by creating banks on
the edges next to the filter basket.
The M-Curve Tamper means the barista does not have to worry about channel formation as
much as before, and also leads to better cup quality.
While channel formation is not the only negative factor in espresso quality, it is a large one.
This is why Maruyama Coffee developed this tool to aid the extraction of high quality
espresso.
Japan Representative barista Mie Nakahara
used the M-Curve tamper the 2010 WBC in
London as well as four other Japanese national
champions, including Hidenori Izaki the 2014
WBC champion.
During this period, use of the tamper spread
among Japanese baristas after that and has
been the official Maruyama Coffee tamper
since,
The Current Generation of M-Curve Tamper:
M-Curve Tamper RM Model
We launched the second and current generation of the M-Curve Tamper, the RM Model in
July 2013. The original M-Curve Tamper is now out of production.
!M-Curve Tamper Remake(RM) Model Specifications
Base : Diameter 58mm × Height 9mm
※ Original model sizes were: 1) 58mm × 11mm, 2) 58.6mm × 9mm & 11mm
Total Height: 95mm (both cylindrical and round handles)
Handle Material: Polyacetal or aluminum (original was ultra high molecular weight
polyethylene - UHMWPE)
Warning We do not guarantee the compatibility of parts of the M-Curve Tamper Original or
Remake models with each other or with any other tampers manufactured by other
companies.