Hi Guys,

I'm struggling to get the right balance between grind/tamp/volume of coffee input/ and volume of espresso output.

I'm using a Rancilio Silvia. It's regularly back flushed and de-scaled. It's running at proper temperature and at 10 bar pressure. I'm using a macap commercial grinder, and a bottomless portafilter. I'm temp surfing the Silvia.

Here's where I'm at - doing a double.

15 grams of coffee input
Tamp at 30 pounds
25 second pour
Output - usually between 1 and 1.3 ounces

I usually make flat whites -and using that combination I'm getting quite nice ones, and I can be pretty consistent. But I still think there's room for improvement.

Normally when I'm making coffee, I keep the grind/tamp/pour time constant, and if I want to fine tune my coffee - I adjust the grams of coffee - usually in 0.50 grams increments. That seems to work well. I don't change the grind, as my grinder isn't stepless. I like to keep the grind constant, as once I change that - I have to muck around heaps getting right the grams of coffee I'm putting in.

Looking at the bottomless portafilter - I'm getting a nice looking pour at the start, but I'm noticing it is getting quite blonde in the last six or so seconds of the pour. I thought about not pouring so long, but then I get a double shot pour of between 0.80 - and 1.0 ounce.

Is it normal for it to be quite blonde in the last 6 seconds? If not, where could I improve things?

Thanks Danny

One strong recommendation I would offer is to not worry about the volume once you've started the shot. Your objective is the best-tasting shot, whatever the volume turns out to be - not, say, a 35ml shot regardless of the taste. Once you've ground, dosed, tamped and your temperature and pressure are set, the die is cast: stop the shot whenever it's done, not whenever it's at some arbitrary size.

Some people argue that a shot should be stopped immediately at blonding, while some prefer running a little longer, which to them improves the balance. One technique to figure out your own preferred stopping point is to split test shots into three or four shot glasses, running perhaps a little longer than usual. This enables you to taste the beginning, middle and end of the shot separately. You can then check the proportion of the final (blondest) part you prefer by re-combining the separated components.

Thanks for your response - that's a great idea to split into containers. I'll definitely try that.

Regarding blonding - just so that I've got it right - is it blonding when the dark stripes in the extraction stop coming through into the pour?

Read the relevant FAQs.

If you want to control brew ratio, you have to do it by weighing your shots as opposed to measuring their volume. Volume varies too much, mostly according to the amount of gas released in the brewing process.

Getting a handle on brew ratios as they apply to your "generic" technique, and as to specific blends and SOs is useful. Maybe not critical, but useful. At least you'll understand whether you like different coffees at different concentrations, or have some preferred ratio. My own taste runs the range of normales... depending on the coffee.

I think Anvan's technique of splitting the shot into timed components will help you understand the secret life of brewing, but you'll learn more about what you like by tasting complete shots, drawn to different stages of blonding. Do it enough and you'll get the idea of what you like, even if you have to do it over several days or even weeks. Just take your time and don't try and break things down too fine, or you'll make yourself nuts. Do Anvan's method too.

What you're really trying to do is balance several different types of extraction ratios. Those include include under/over extraction ratios as functions of time of the pull; as a function of the relative weights of dose and shot; and as a function of degree of blonding (for lack of a better term).

As you go along, you'll find that tamp pressure is one of the least important aspects of technique. But for now try and keep your tamp force consistent. With a consistent tamp (and it doesn't matter too much how much force you use as long as you don't use too much and jam the pour), you'll learn to vary time with grind. Grind is one of your most important and powerful tools. You can learn a lot about it by timing the pour, but you'll learn more by tasting.

You'll also want to perfect (or at least improve) the way you load the basket. Channeling is a big part in over and under extraction, and it's hard to really know what's going on without a naked pf. Read the FAQ.

No matter what measuring device you're using, watch, scale, graduate, etc., your palate is your best instrument.

Finally (for now), there's a limit to how far you can take a Silvia because the temps are so inconsistent.

BDL

The one important factor I don't see mentioned is the coffee you're using...most specifically the roast date? You want to work with beans that are finished degassing (3 to 5 days after roasting) and not much past 12 days (depending on the coffee and roast level).

You never mentioned the type of coffee beans you're buying. Try finding fresh roasted beans as danetrainer said. That will be a huge improvement.

danetrainer wrote:The one important factor I don't see mentioned is the coffee you're using...most specifically the roast date? You want to work with beans that are finished degassing (3 to 5 days after roasting) and not much past 12 days (depending on the coffee and roast level).

Thanks guys,

I'm using freshly roasted beans from our local roaster. I'm not sure what type they are off the top of my head, but they're the same blend that is used in the cafes they sell to.

One other question. When I'm taste testing my espressos - I find that once I've got the taste of coffee in my mouth (especially if it is strong), that I have trouble distinguishing the flavour subsequent coffee's. Is there something you guys use to wash out your mouth with between coffees, to cleanse the palate?

disgrace wrote:Regarding blonding - just so that I've got it right - is it blonding when the dark stripes in the extraction stop coming through into the pour?

Yes.

Dan's advice to watch the stream's texture is solid. It's more obvious than many other visual cues. Obvious is good.

Depending on the visual background, color of the cup, available light, etc., you can often see blonding more clearly as a light colored pool forming on the surface of the pour, than by judging the stream's stripes. Blonding is a process which begins early in the brewing cycle, and is more a question of degree than an absolute point in the pour.

Is there something you guys use to wash out your mouth with between coffees, to cleanse the palate?

Fizzy water.

BDL

disgrace wrote:Is there something you guys use to wash out your mouth with between coffees, to cleanse the palate?

Check out this thread for many more ideas on that. Saltless crackers with cream cheese might be a nice bet. Or vodka, if you're into that kind of thing. Something to get the coffee oil off your tongue. Soda water is good too. I make my own, and make it as fizzy as I can.