Posted Wed Apr 3, 2013, 10:17am Subject: Re: Ceramic vs metal grinder - which is better
simply quoting kyle anderson from baratza to answer your question (11+ years of experience in designing coffee grinders):
"Heat and grinding coffee beans: the big misunderstanding
Thermal conductivity of the burrs (i.e. The material they are made from) has NO BEARING on the root cause of heat build up in grinders which comes from a combination of internal friction as the coffee bean is crushed, and from minor friction in the actual cutting of the bean by the burrs. The sharper the burrs ,the less heat is created in the cutting of the bean. The majority of heat creation comes from the crushing of the bean. One could actually argue that the higher thermal conductivity of steel burrs can actually decrease the heat of the ground coffee in small batches. This is because the heat is created IN the bean and is then transferred to the burrs. If the burrs are steel, they will do a MUCH better job of transferring this heat away from the coffee and to the housing of the grinding mechanism. The actual surface temperature of the grinding surface will be similar whether the burr is steel or ceramic, except for that heat which is able to transfer through the burr and away from the coffee. In large industrial coffee grinders, the burrs are mounted to a plate that has water cooling running through it. The burrs conduct the heat away from the beans (and the grinding surface) to the water. A secondary source of heat in ground coffee comes from heat that is stored in the burrs and grinder housing (from coffee ground earlier or immediately preceding) and transferred back into the coffee being ground in the moment."
Bottom-line: Durability is the main difference between steel and ceramic...ceramic will be significantly more durable is not chipped by a rock hiding in coffee beans.
Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post
Forum Rules: No profanity, illegal acts or personal attacks will be tolerated in these discussion boards. No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum. No SEO style postings will be tolerated. SEO related posts will result in immediate ban from CoffeeGeek. No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum. Who Can Read The Forum? Anyone can read posts in these discussion boards. Who Can Post New Topics? Any registered CoffeeGeek member can post new topics. Who Can Post Replies? Any registered CoffeeGeek member can post replies. Can Photos be posted? Anyone can post photos in their new topics or replies. Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts. Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.