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Thread: Any advice ... ?

  1. #1
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    Any advice ... ?

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    Hi,
    I am quite new to the roasting scene - I have only got a few roasts under my belt. I use a large stainless steel bowl and a GMC heat gun, which has been excellent so far.

    My question relates to two roast batches I did today. I was aiming to roast both of them exactly the same way:
    * start out with the heat gun on a stand at low/medium heat, maximum airflow (nozzle about 7 cm away from surface of beans);
    * vigorously mix the beans for ten minutes while gradually ramping up the temperature;
    * by the end of ten minutes, the heat gun is at its maximum temperature, and the beans are pretty uniform tan/beige colour;
    * at this point, take the HG off the stand and hold it closer to the beans while still stirring in order to progress to the first crack.
    * first crack occurrs at about 13/14 minutes (reasonably prolonged cracking - possibly leading into second crack, but I have not been able to tell the difference so far);
    * after about 1 minute of cracking, I put the beans in a colander and tossed them repeatedly in the air to cool them down.

    This method has resulted in a roast that looks fantastic - uniform chocolate colour with no oil spots. This is despite the green beans being a blend of four varieties. Both batches looked like this. I was also able to compare the colour of the result with a professionally roasted version of the exact blend I used, and they looked identical - perhaps with the professionally roasted beans having a few oil spots.

    This is the thing which has confused me - despite the same technique for and identical appearance of both batches, they smell totally different. To quote my wife, the first batch now smells like cigarette butts, and the second one smells caramelly and beautiful. It is possible that the first batch was allowed to crack longer than the first, but I wouldnt bet my life on it.

    Does anyone have any ideas as to why this might be? And a further question - if a roast smells like cigarette butts will it taste like cigarette butts?

  2. #2
    Mal Dimal's Avatar
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    Re: Any advice ... ?

    Hi Dr.GTD,

    Im no expert on the use of the HG/DB method of roasting, use a slightly modified popper to keep me going.

    It sounds from your description though, as though you are taking a bit too long to get the beans to 1st Crack. If it was me, I would be trying to get to first crack in under 10 minutes, probably at around 7-8 minutes and to 2nd Crack in roughly 5-6 minutes after that.

    It could be that when you move the HG closer and ramp the heat up at the same time, you are accelerating the roast process just a bit too quickly at the time when you should be exercising some level of restraint in order to maintain control of the roast. Why your first batchs aroma should be significantly different to the seconds could be due to any number of things occuring, including under/over roasting.

    The only time Ive experienced what you describe is when I over-roasted one particular batch of Brazilian Santos beans but in my case, there was plenty of oil evident on most of the beans even though the bean colour wasnt all that dark. Maybe one of our more experienced contributors could offer more focused advice for you. All the best,

    Mal.

  3. #3
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    Re: Any advice ... ?

    Thanks Mal - your advice is much appreciated.
    My reason for trying to hold off on the first crack is that I have seen a couple of graphs of roasting profiles which wait that long unitl first crack. An example of this is a HotTop graph I found at http://www.coffeegeek.com/forums/coffee/homeroast/8492.
    I must admit though, even the coffee that smelled nice tasted a bit weak relative to the professionally roasted one.
    I will roast a batch today according to your advice. I am looking forward to being able to discern the second crack. I obviously havent even gotten close to a second crack yet, because I have not continued to roast for longer than about a minute after the cracking starts so far (everything gets so dark so quickly!).
    Will return with the results!
    Thanks again,
    Steve.

  4. #4
    Senior Member robusto's Avatar
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    Re: Any advice ... ?

    DR.GDT, from your description youre turning out evenly roasted beans. Go by the taste, rather than smell or whether youve reached second crack. I wouldnt get too hung up on timing for second crack. Observe the time it takes for first crack, then, keep roasting until the beans are your preferred colour. Observe the time its taken to get to that point, irrespective of whether second crack has occured. In future, you then roast to first crack PLUS that whatever that second timing was. Works for me in the barbecue roaster -- I have to rely strictly on timing because I cant see the changing colour of beans within the drum.

  5. #5
    Super Moderator Javaphile's Avatar
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    Re: Any advice ... ?

    You might want to try reversing your heat ramp-up. Usually one ramps up the heat to get to first crack and once that is reached the heat input is turned down so you can coast into 2nd crack. If you ramp the heat up at first crack you can then go immediately from 1st too 2nd crack with little or no break inbetween.

    Mals advice on the timing of the cracks is right on the money. Aim for 1st crack at 7-10 minutes with 2nd crack at 14-17 minutes.

    Somenting to be aware of is that most coffees have their sweet spot before 2nd crack. Once 2nd crack is reached the roast flavor starts increasing dramatically. See all that smoke thats suddenly appearing? Thats the sugars in the beans burning. Other flavors in the beans are burning up right along with the sugars.

    In my experience I have found that the vast majority of beans have their sweet spot before 2nd crack is reached with some beans being almost undrinkable if theyre taken into 2nd crack. The Colombians are a good example of this. Once 2nd crack is reached with them their flavor rapidly degrades and by the time they hit the rolling 2nd crack they taste horrible.

    In general, if you want the maximum flavor of the bean you most likely wont ever reach 2nd crack. If on the other hand you prefere to taste the roast flavor then youll be taking the beans into 2nd crack.

    Java "Gimme da bean flavor baby!" phile

  6. #6
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    Re: Any advice ... ?

    Thanks for all your advice. This site is an absolute godsend for me as a roasting newbie.
    Well - I have just come in from the backyeard smelling of coffee smoke. I have done another roast. I cranked back my timing. Got to first crack at about 7-8 minutes, and backed off a bit. I think the first crack went for about one minute. There was a break in the action for a while, and after a few minutes I started hearing faint cracks. I think I have lost my second crack virginity!
    In any case, I stopped soon after the start of the second crack, and I have ended up with a very consistent looking roast. I am very curious as to the taste of this one, as it looks the same as my first two attempts, but the process in getting there is quite different.
    Java - I think my taste in roasts may be aligned with yours. I will report back when I taste this one tomorrow morning.
    Robusto - in accordance with your advice, I am going to give the cigarette butts a good go tomorrow morning too. Perhaps a blind tasting so that I do not imagine cigarette butts as I am drinking it! The wife says shes curious to try the ciggies too! I will report back.
    Steve.

  7. #7
    Super Moderator Javaphile's Avatar
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    Re: Any advice ... ?

    It sounds (no pun intended of course ;D ) like you did indeed reach the 2nd crack. Congrats! :D

    I think its helpful to the roaster to have an understanding of what makes up a bean and what the physical changes are that it undergoes during roasting.

    Coffee beans are basicly wood and are comprised of 2 different components that the roaster needs to be aware of. These are cellulose which is the fibers of the bean, and the juices in the bean, ie all the water, oils, acids, and sugars etc. in the bean.

    With-out these juices, cellulose is just flavorless fiber. All the flavor in coffee comes from these juices.

    When coffee beans are roasted they go through a series of physical changes. As the roast is started and the bean starts to heat up the juices (mainly water at this point) in the bean begin to boil and turn to steam and pressure builds up inside of the bean until its shell is no longer able to withstand the pressure and *pop*, the bean splits open just like popcorn and we have first crack. At this point it is mainly water being boiled off as the bean has not yet gotten hot enough to boil the oils and sugars. As such the bean is still light in color. As the roast progresses and the temperature of the bean rises more and more sugars reach their boiling point and start exuding from the bean and as the liquid portion of them is boiled away they caramelize. It is this caramelization that causes the color change we see in the beans. As the roast continues more and more of these juices are driven to the surface of the bean as it continues to rise in temperature. Finally the boiling of these juices reaches a crescendo and the inside of the bean is under so much pressure that the fibers of the cellulose itself start to split apart. Voila! We have 2nd crack! All the juices continue to madly boil away until, if let go far enough, they all boil/burn away leaving us nothing but a piece of charcoal and eventually (after weve put the fire out) a pile of ash.

    As the bean darkens approaching 2nd crack it is the sugars (mainly) in the bean burning off and caramelizing on the surface of the bean that is causing the color change we see. The darker the bean gets, the more sugars there are that have been burnt off. As sugar caramalizes and then burns it looses sweetness, so as the bean darkens it is loosing the sweetness of its natural sugars resulting in a more bitter tasting cup of coffee.

    Another of the juices we are concerned with as it relates to taste are the acids in the beans. As the bean heats up approaching and then entering 2nd crack the acids boil off. Thus making the resulting coffee less acidic the farther the roast is taken.

    The last major component of these juices in the bean that were concerned with are the oils. Because the oils have such a high boiling point they dont make their way to the surface until the beans are usually well into 2nd crack. When oil starts appearing on your beans you know that many of the acids and sugars have already boiled off. If the roast is continued until the beans are well oiled the resultant cup will have a very sharp bitter taste as most of the acids and sugars have been boiled/burnt off.

    Generally speaking (based on a roast cycle of 1st crack at 7-10 minutes and 2nd crack at 14-17 minutes) you will find bean flavor peaks in the 90 seconds before 2nd crack starts with a few varieties peaking just into 2nd crack. As you approach and then enter 2nd crack the roast flavor quickly starts to take over and the natural flavors of the beans are reduced.

    Determining when to stop a roast then is a matter of balancing the boiling off of the acids as the roast progresses against the caramelizing and burning of the sugars to suit ones personal tastes.

    Hopefully this has helped you and not bored you too death. ;) Welcome to the wonderful addiction of roasting your own coffee!

    Java "Hello, my name is Javaphile and Im a Roastaholic" phile

  8. #8
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    Re: Any advice ... ?

    Java "the legend" phile ;D,
    your advice is exactly the sort of information I have ben looking for. Roasting can appear to be a bit of black magic to a newcomer, and what you say demystifies it a little bit. I wish I didnt have so much backlogged roasted coffee so that I could go out again now and give it another crack (no pun intended)!
    When considering your advice, I have probably over-roasted all my beans, and the nicest-smelling one is probably less over-done than the others. Wife and I have both commented that none of my roasts so far have that real knock you over coffee smell that you sometimes get from freshly and professionally roasted coffee (I am lucky enough to live 10 minutes away from Fresh_Coffees store, Cosmorex). Also, although my shots are OK with my roasts, they are not the sort of standard that I have managed with FCs freshly roasted coffee - I have to grind a little finer than normal to get the proper extraction rate. The whole thing has got me very interested, and I feel as though I will slowly learn enough to get it nailed.
    I am yet to taste the ciggie roast, as there was still some of the nicer roast left in the grinder this morning, and I didnt have the heart to get rid of the half-ground stuff.
    Cheers!
    Steve.

  9. #9
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    Re: Any advice ... ?

    Dr.DTG
    * While no where near the league of roasters such as Javaphile, I will throw my two bobs worth in that it may also help other newbie roasters with some of the technical talk. ;)

    Firstly, when roasters talk roasting times, its from profiles they are use to, with beans they are familiar with, using equiment they know deftly. Only when you are using the SAME bean, the SAME equipment and the SAME roasting profile can beans be truely compared. Hell, even the humidity effects the roast. ::)

    It does make a difference if you preheat your beans, and that counts as roasting time. *As does the cooling method, cause until theyre cold, theyre still cooking. :o

    Secondly, allow the beans to degas after roasting. Most of the roasts Ive done dont smell of that pleasant coffee smell straight away. The Sumatran comes up within a few hours, yet Ive found the Columbian to peak a day or two afterwards. ;D

    Hope this helps to even out the frustration wrinkles. I remember trying to watch the clock, look for this and listen for that, and I went nuts in the process, couldnt get it sorted. Then someone explained that my starting point was different to where the information was comming from, hence the different finishing point. :D

    As to the cigarette smell, if its a blend, it maybe because different beans roast with different profiles, while one is just hitting the sweet spot, the others might not be there yet, or worse yet, past it. So in a multi bean blend, Guestimating the finish point may leave some beans over or under done hence the confusing smell. In your second roast, was everything preheated? It will effect the outcome.

    Have you roasted the beans as single origin roasts to see what they are like by themselves? One you work out their individual profile, youll have a better understanding of how to roast the blend.

    Cheers

    Boris.

  10. #10
    Super Moderator Javaphile's Avatar
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    Re: Any advice ... ?

    Steve,

    As Boris pointed out freshly roasted coffee generally doesnt have a whole lot of smell fresh from the roaster. That great smell comes out as the coffee degasses and then you get a big nose full when you grind it. :D

    I love coming downstairs the day after a roasting session and getting that first waft of fresh coffee smell coming from the cupboard where the beans are resting.

    Also realize that the smell you get in commercial shops is there because for the most part they over-roast their beans. This causes them to release more of their smells (as more of their juices have been brought to the surface of the bean by the darker roast) as a whole bean. The smells in a commercial shop are also stronger because youre smelling hundreds of pounds of beans of many different varieties whose smells are mixing and reenforcing each other.

    With this in mind I wouldnt be overly concerned with the smell of your whole beans. The proof is in the pudidng as they say. How do they *taste? :)

    I would also take Boriss suggestion to try roasting your coffees as single origins before you attempt to roast them as a blend. The roasting time needed to hit the sweet spot will vary dramatically one bean to another. What I prefere to do is roast as a single origin and then try differnet blends using the already roasted SOs. This allows you to try many different blends from a single roasting session.

    One final thought, only put enough beans into the grinder to grind enough beans for what you are brewing up right *then. Ground coffee begins loosing its flavor almost immediately upon being ground. Ground coffee should be used with-in 30 seconds of being ground to maximise its flavor. Waiting just a few minutes to use it after grinding can reduce its flavors by well over half, also leave your whole beans in their airtight container to help preserve their freshness until you actually use them. :D

    Java "Follows his nose upstairs to try some Upside-Down Peru Villa Grace" phile

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    Re: Any advice ... ?

    Hi there everyone,
    Sorry for taking to long to get back to my computer.
    First of all – my coffee roast reviews:
    Caremelly roast: nice, but somehow not that fully flavoured
    Ciggie roast: not too bad, but a bit bitter
    Roast taken to start of first crack (following Java’s advice): probably nicest of the bunch. Pretty tasty, with a bit of that roasty taste to it. No unpleasant at all, but will probably aim to roast the next batch a little less.
    It is really difficult to provide a decent review on these, as I would suspect that my brewing technique would account for much of the differences too.

    Boris, thanks for the advice. You’ll never believe it, but I only just a few nights ago combined all my beans into the one container as I felt I was having some success with consistency. Wish I hadn’t!
    As for your comments about warming the beans – that was kind of my intention with the long ramp-up time. My theory was that because it was a blend, I could heat all my beans up gradually until they were all sitting on the edge of first crack so to speak. When I felt I had reached that point, I turned up the heat, and pushed them all over. Is this what you mean by “warming the beans”?

    Java – I have found that the beans smell more and more coffee like as the days go by. Interesting. The more they smell like coffee, the more stale they are getting.

    Anyway, thanks for your valuable advice – I can’t wait to roast my next batch!
    Steve.

  12. #12
    Super Moderator Javaphile's Avatar
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    Re: Any advice ... ?

    Behmor Coffee Roaster
    Quote Originally Posted by Dr.GTD link=1114856735/0#10 date=1115318236
    Roast taken to start of first crack (following Java’s advice): probably nicest of the bunch. Pretty tasty, with a bit of that roasty taste to it. No unpleasant at all, but will probably aim to roast the next batch a little less.
    I hope you meant to the start of 2nd crack and not first crack. Beans taken only to the start of 1st crack would taste a bit underdone to say the least. ;D ;D For my tastes Ive found most coffees taste best roasted shy of 2nd crack with very few having their sweet spot at or into 2nd crack. :)

    Quote Originally Posted by Dr.GTD link=1114856735/0#10 date=1115318236

    Java – I have found that the beans smell more and more coffee like as the days go by. Interesting. The more they smell like coffee, the more stale they are getting.
    I guess it would depend on how one defines stale.

    From a scientific viewpoint theyre beginning to go stale as soon as theyre pulled from the roaster and the oxydization/molecular degradation process begins, an arguement could even be made that this begins at the start of the roast.

    From a taste perspective with stale meaning theyre past their prime flavor they would not be considered stale until several days after being roasted. The beans would be improving in flavor for the first day or two and then be at peak for 2 or 3 days after which they would then be going stale.

    It all depends on ones definition/viewpoint. ;D ;D

    Java "Gotta love the English language!" phile



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