I have heard that Barry Callebaut is working with starter cultures for their fermentation that gives great and consistent results for their fermented beans.(like yoghurt, beer, wine, cheese makers)
I am not so much interested in the consistency part, however the it is very exciting opportunity to create required flavour profile for the beans, like microbreweries do with their yeasts. It gives the opportunity to work with desired cultures, not just whatever "falls" and multiplies in your batch of beans.
Does anybody have any info on this? Should it be possible to use starter cultures used in other products like beer? Where can I find cultures that I can experiment with?
The three things you'll need are yeast, lactic acid bacteria, and acetobacter, very concentrated. remember that naturally, there are dozens/hundreds of strains out there that are all competing with one another. At the end of the day, it usually doesn't really matter a great deal which strains you have (there are a few exceptions, but not nearly as many as you'd might expect with the thousands of combinations). while the callebaut work is actually being done, it's really more for marketing than affecting actual large scale results. others have been doing this type of thing for many, many years and are significantly more progressed in their understanding and usage of these techniques than callebaut.
Any brew house can give you the yeast, i've never looked for retail available acetobacter or lactobacter, but i'm sure they're available as well. It's important to understand the fundamentals of fermentation before starting to try to tweak the components of fermentation, so i'd encourage you to be certain you've got the basics of that down first otherwise you're going to just get frustrated and not understand why.
Vicente Norero in Ecuador -- Camino Verde -- is offering several different fermentations from the same beans so I know that there is someone doing this on production scale and you can buy the beans and taste the differences.
Also, I have heard that the Rizeks in the Dominican Republic have been doing the same for some of their clients. I have not visited either facility so I don't know any of the specifics.
There are commercial sources for yeasts for the various alcohol industries - beer, wine, and spirits. Wyeast Labs is one source I know that several of my beer, wine, and mead friends use. If you wanna go all serious and stuff on this project, Lallemand may be a place to try.
One thing to consider when sourcing yeast for fermenting cacao pulp is that the pulp has a pH in the 3.5 range so you're going to want a yeast that is comfortable working at this level of acidity -- not all yeasts are.
The Rizeks are going to be the most advanced of the non-privatized folks to work with on this topic - they've got a very nice set up there that a member of this board helped them build in fact. Marcello Corno would be your main technical contact there, and they have a small micro laboratory on site at their main production facility. As noted, yeast selection doesn't really matter as long as the strain is viable, and it only needs to be viable for a portion of the fermentation as it will be quickly outcompeted by the other two phases. I've just reviewed some of my historical pulp pH data - now - and this is critical - assuming you've got relatively fresh pods, undiseased, you're going to have a 95% probability that your T0 pH will be between 4.74 and 4.93. That pH will drop over time as the acetobacter and lactobacter kick in, to be sure, but by the time that occurs that yeast's job is done (it's main functional job is to convert sugar to alcohol - which is important for a number of reasons) - but once that's done, it doesn't matter if the yeast lives or not.
T0 is when the pod is opened?
In our experience in fermenting juice for Solbeso, by the time it arrives at the collection center between 4 and 8 hours later, pH of the juice has dropped considerably into the range I mentioned.
One of the tricky things to manage - especially at larger fermentaries where the cacao isn't grown where it's fermented - is to be sure to manage the freshness of the beans. The second you split open a pod - fermentation begins. Jungles are wonderfully effective incubators, and there's yeast, mold, and bacteria everywhere, just waiting for you to open a sugary pod up and let them begin to feast. Typically the farmers open the pods, collect enough to transport, and then transport - if you're able for receive these beans w/in 8 or so hours of them first being opened, you're going to still have a high bris level (sugars), which is your primary indicator of how much fermentation has progressed. Acidity doesn't really start to play a part until the secondary and tertiary fermentations of lactic and acetic kick in - if you're observing pulp (juice) pH in the 3 range, it's a very clear indicator that either fermentation has been underway for some time (i.e. the beans were harvested before you think they were), or there's a significant disease/pest impact at play. I suspect that if you were to go to the farms and trace the supply chain, starting the clock from when the first pod is cut open to the time it arrives at the fermentation center, you'd find the time is considerably longer than 4 hours...
Edit - huh i've never seen solbeso - is it available in the US?
I will check into the pH levels with our master distiller when I am in Peru in July and get back to you.
Solbeso is now available in the US. We're registered for sale in New York and Florida and I think we can ship to 48 of the 50 states if you're not in NY or FL. LMK and I can send you the names of our retail partners who ship.
It's an interesting liquid. It has no taste of cacao/chocolate, but is reminiscent of pulp. 40% ABV, so it's formulated for use in cocktails but can be drunk neat or over ice (it behaves a lot like a brown spirit - water softens it and opens it up). Good cocktails are in the sours and international sours families. One of our signature cocktails is called a Beso Picante - hot kiss. Solbeso, lemon juice, orange liqueur, and heat -- cayenne pepper, habañero bitters, muddled jalapeño/cucumber ...
Solbeso also makes a great Michelada. We did one at Taproom 307 here in NYC during Beer Week -- the Midnight Sun Michelada -- that was lime juice, Solbeso, spicy tomato water (from pico de gallo), and a splash of Worcestershire. Shake, pour into a pint glass (salt-rimmed if desired), fill with a black IPA, and garnish with a pickled jalapeño slice and a lime wedge.
It also goes great as a beer shot/boilermaker with Cusqueña lager.
Interesting. I'll be up in NYC a bit next week, and more so the week after.. I'll have to look for some.
Peru in July - are you going down for the chocolate trade show? Someone offered to pay my way for a week if i came down to speak - and i'd love to - but i'm afraid it's not good timing for my family. Next time 8-)