malachi wrote:Given that the shot that Marshall was served that inspired this whole bout of self-examination was from a PID controlled La Marzocco... I think we can clearly say this is not the case.

Good point. I had thought of that and had no answer to it, but I just was so interested by Jim's comment on the DC Mini review thread that I thought it was worth asking if it is possible for a machine to be almost too stable. (Below is the quote I was referring to)... If the La Marzocco is just as stable, why isn't it like the spotlight instead of a floodlight - or is it just that they nailed the best temperature perfectly in this case?

Another_Jim wrote:This may because of the flat line temperature profile. It could be analogous to shining a spotlight, picking out some things with great clarity, and leaving others in the dark. A humped profile is more like a floodlight, it may be more intense in one direction, but the whole room gets lit up. In any case, I was running my darker roasted cappa blend for straight shots. At cool temperatures, it was easy to pick out the tobacco, blackcurrant, and clove flavors from the Guat/Kenya blend I was using, but the taste was kind of raw. At higher temperatures, the shot became warm and carmelly, but lost its distinct flavors, the tobacco and blackcurrent were gone, the clove was just a hint.

It could be that the lack of clarity has something to do with this extreme variability on the temperature response. At the wrong temperature, some of the signature flavors of a blend might disappear.

I think the "humped" vs "flat" description above is more conjecture and speculation than fact.

Certainly this is conjecture, even more so than everything else in espresso. I was just struck at the qualitative changes I got twiddling the DC knob, as opposed to the simple taste balance changes I get changing the flush on an HX.

In any case, experiment soothes the mind. Friday, we'll be blind comparing three different coffees on the DC and Elektras. The shot designated worse gets tweaked for the subsequent round (no tweaking if there's no difference). The evolution of scores will tell a story, and the comments of tasters and the sort of tweaking done will flesh it out.

With any luck, it will raise the literacy level of the double boiler versus HX speculation; which is what I really want from my experiments.

Marshall's (and us reviewers, so far) problems with the DC are very surprising to me. I always thought it was the DBs which were terribly honest, while the HX machines, especially the E61s, saw the espresso world though rose tinted glasses. For instance, I was picking up test coffees today, and had superb shots of both Black Cat and Red Line (compliments to both Baristas). They followed my prejudice in the matter: The Black Cat shot from the GB5 was a very crisp 70% chocolate with a sour cherry filling, the Red Line shot from the Mirage was runny sweet milk chocolate and apricot jam.

To some extent, the perception of clarity is one of structure, i.e. slightly astringent flavors "outline" the different notes, as in wine (or a great Kenya). And to a further extent, it is one of timing, with the aroma, crema, emulsified oils, water dissolved flavors, and retro-nasal aromatics all distinct and hitting at different times, similar to the way a complicated confection or candy bar has a sequence of tastes. Structure and timing separate the flavors in auspicious shots that can run together in less auspicious shots.

Sorry... was not clear in my communication.
The difference in flavour profile produced by the two temp profiles is not at all conjecture.
A causal relationship between one or the other profile and enhanced perception of "clarity" is, however, in my opinion conjecture.

Marshall wrote:Bar Bambino on Mission St. in San Francisco. Richard Reynolds took us there specifically for the coffee.

Gor! When I went there, there were bones in my stew and the food was salty to the point of being inedible. The espresso was pure crap. I sent it back twice, because I had heard the coffee was supposed to be good. Each time it was thin, bitter, and overextracted. The wait staff couldn't care less. No apologies. No taking the cost of the stew with the bone I choked on off the bill. Nada. I guess they were pulling in enough money that they figured they didn't have to work on getting return customers. Well, they won't.

Marshall wrote:They immediately understood what I was talking about and said that the deep and narrow La Spaziale and Dalla Corte baskets were good at producing sweet, chocolaty shots, but could not do "clarity" like a La Marzocco. In fact, Kyle said he thought lever machines produced the most clarity.

So obviously puck shape (and thus the rate of flow, time to temperature & pressure stability, etc) has an impact on flavor. It may be fairly dramatic since a smaller basket diameter simultaneously increases cylinder height while decreasing cross sectional surface area.

What I wonder is if using a smaller diameter basket mimics the effect of overdosing? Can we thus increase cup clarity in smaller diameter baskets by reducing the dose?

drdna wrote: What I wonder is if using a smaller diameter basket mimics the effect of overdosing? Can we thus increase cup clarity in smaller diameter baskets by reducing the dose?

No. As far as I can tell, the DC gets clearer when overdosed. If anything, the machine tends to an over extracted flatness at low doses.

The DC is a very odd machine. I wonder what gives it its idiosyncratic qualities. Just when I think I might be beginning to understand espresso, I am humbled to realize I know nothing at all.

drdna wrote:The DC is a very odd machine. I wonder what gives it its idiosyncratic qualities.

I wonder whether the larger Dalla Corte Machines, either the Super Mini or the commercial machines, share the same idiosyncrasies.

I guess the Grand Unified Espresso Theory still has a way to go.

another_jim wrote:No. As far as I can tell, the DC gets clearer when overdosed. If anything, the machine tends to an over extracted flatness at low doses.

Jim has been getting unexpected results from the DC Mini, and we should be hesitant to generalize. This has not been my experience on the Spaziale S1, arguably the most similar machine (double boiler, smaller basket diameter).

drdna wrote:So obviously puck shape (and thus the rate of flow, time to temperature & pressure stability, etc) has an impact on flavor. It may be fairly dramatic since a smaller basket diameter simultaneously increases cylinder height while decreasing cross sectional surface area.

What I wonder is if using a smaller diameter basket mimics the effect of overdosing? Can we thus increase cup clarity in smaller diameter baskets by reducing the dose?

Not all double baskets are taller (e.g., the 51mm Gaggia Factory lever double is not). But the DC and S1 double baskets are taller as well as smaller diameter, and thus might exhibit some of the extraction characteristics of triple baskets.

Whether downdosing per se leads to greater clarity is an interesting hypothesis, but not an easy one to test. Downdosing tends to produce pours with a lower brew ratio, which could account for a greater separation of flavors and a perception of greater clarity. Lower doses require a finer grind, which impacts taste. There is a temperature effect, since larger doses lower the incoming water temperature more than lower doses. And increased cylinder height creates an extraction gradient, with upper layers extracting more than lower layers in the puck.

I've played around with dose-related taste changes since your post, and they are readily discernable. But it's not clear what causes these effects, and whether clarity is the right terminology. I'd be interested in hearing more thoughts on this topic.

drdna wrote:Gor! When I went [to Bar Bambino], there were bones in my stew and the food was salty to the point of being inedible. The espresso was pure crap. I sent it back twice, because I had heard the coffee was supposed to be good. Each time it was thin, bitter, and overextracted. The wait staff couldn't care less. No apologies. No taking the cost of the stew with the bone I choked on off the bill. Nada. I guess they were pulling in enough money that they figured they didn't have to work on getting return customers. Well, they won't.

Hi Adrian,

Off topic, but since it's something that can influence somebody's business, I want to point out that I went there for the prix fixe Valentine's Day dinner, and had one of the top ten meals of my life. And I'm sixty. I'm not saying that either of our experiences are representative, since each of us is a sample of one, but it's certainly not always bad.

Best,
David