MENU - PARTNER AREA

Coffee beans (roasted)

Protocol number:	M200082
Industry:	Biology, Foodstuffs
Feed Size:	10 mm
Desired Fineness:	100 % < 2 mm
Quantity:	100-200 g
Recommendation:	For small quantities, also the desired Knife Mill PULVERISETTE 11 can be used to grind the sample to < 2 mm (even finer).

Result 1

	Knife Mill PULVERISETTE 11 speed: (reduced) 5000 revolutions per minute
Equipment:	vessel: 1,4 L scratch-resistant plastic Tritan knife: Standard knife made of stainless steel lid: Standard lid made of silicone
Feed quantity:	140 g
Feed Size:	8 mm
Grinding time:	2 min
Final fineness:	majority < 1 mm
Comments:	140 grams of the roasted coffee beans were used for this test. The grinding vessel was filled by ~ ¼ of available volume. Surely the double amount of sample could be used as well. The Tritan vessel was equipped with our standard knife and a silicon lid. The speed was reduced to 5000 rpm; we would expect that such a oily sample would slow down a spinning knife and the mill might not reach the maximum speed of 10.000 rpm (14.000 rpm with turbo mode). We ground the sample for a minute and found plenty of fine ground fragments. After two minutes, no significant improvement in fineness was observed. Only a few particles were left > 1 mm. The fineness of 100 % < 2 mm was already reached. Most likely, a sickled knife would have less of resistance (compared to a standard knife) and should achieve a higher speeds for even finer results. The equipment was cleaned with water and soap which was fun in short intervals for ~ 20 seconds. Afterwards, the equipment was flushed and dried off.
Pictures:	Original coffee beans (roasted).
	Ground sample (140 g) inside the tritan grinding vessel.