A lot of Acid

Hi! I really need advice.

I keep on having problems of making chocolate that taste acidic. I've made 7 batches so far.

Each with different temperature, mostly either short high or long low.

Especially the long low roast a little more than half way I get this scent of acidness and at the end resulted in a little bit of a burned brownie smell.

Many roast I would get this nice smell of chocolate aroma.

But despite all these roasting which turns up to be smelling either nutty or chocolaty smell, every batch I pour into the melanger, I would get this instant rush of acidic smell, and when it turn liquid I add in sugar I tried 70%, 62% 60% 52%(with milk powder) first 2 batch I'm surprise to see that after 6 hours I would get this fine chocolate already, but I let it run until 12 hours. All the batch after that are 20-25 hours. After conching I would pour it into a container and let it settle a bit and store it into the fridge for 2 weeks. After 2 weeks, still some acidic taste.

May I know what I did wrong. The ingredient are only beans and sugar, I have no access to lecithin or cocoa butter at all.

I mostly keep the lid on, because I let it run over night, and it make a lot of mess when open. I sometimes use the hair dryer like 5-10 minutes.

I also look at the farm that supply the beans and it is certified by the local research center for quality.

What could be wrong? The conching time is not enough? More hair dryer? Longer and hotter roast? Need to open the lid?

Thank you in advance for all of your advices.

updated by @panod: 04/10/15 05:20:41PM

All of those haven't been tempered yet, and right now it smell acidic and unwelcoming. :S

You're quite likely not doing anything wrong; what you're seeing is the result of fermentation, which generates lots of organic acids - and may have been left to go longer than it probably should have. Remember that there's no 'right' way to ferment beans - this farm you're working with may very specifically be targeting acidic beans, as that may be what someone has directed them to do in the past for a specific flavor profile, be it alone or in a blend. Or it could be that they screwed up. Hard to say w/o more details. You've got a few options you could try, i think:

1) Roast at a lower temperature, for a longer period of time. You might even consider wetting the beans a bit and trying to steam off the acetic acid by azeotroping it. I probably wouldn't start with that, but it might be something to try at a later time of other approaches don't give you what you want.

2) Take the lid off your melanage, and let it melange for 3x as long. Acetic is a fairly low molecular weight organic acid - you can tell this because you can smell it. If it wasn't, you couldn't smell it. It wants to go away. You're trapping it in by keeping the lid on, and the longer you let the cycle go, the more opportunity it will have to escape. Also consider heating environment (keep it below 160F) as heat has a direct impact on volatility.

3) Try adding a little bit of baking soda to your batch. Baking soda (sodium bicarbonate) is a very weak base. You've got some acid present. Give the two a chance to dance and neutralize one another. You'll have to play with the levels, but i'd start very low.

Just noticed your location. Do you have any insight as to how the beans were dried (or better yet, any influence over how they're dried?). Which country are the beans coming from (i'm assuming they're in your region..)

Thank you Sebastian for your insight, I'll keep the lid off and let it conche for ~36-48 hours. And will add baking soda after 36 hours(If it still smell bad). Like 1/2 teaspoon? I'm making a 400 g batch.

At the beginning of next month I'll be visiting the farm down south to see how they grow it. Will post pictures

Thank you Sebastian!

I would say look for better quality beans. If using over fermented beans and without the ability to truly conch properly you have a big challenge. Ideally, starting with carefully and properly fermented beans, as well as quality fine flavor beans, will make your process more forgiving. This is why the big manufacturers can use all kinds of lesser quality beans, they have highly sophisticated equipment, and conches to deal with these issues, and they are professional blenders, so when they run into acidic or vinegar acids, they can deal with it easier. Small producers trying to conch and refine in a melanger don't have that benefit, and using single origin beans makes you vulnerable to fluctuations beyond your control. We find in our test kitchen that the better our beans, the better our results. Get yourself a fermentation chart so you can compare your beans against the chart for proper fermentation. There are roasting charts also that can assist. I believe at the end of the day, bean quality and fermentation and drying are very important. UWI cocoa research unit has some very interesting studies on fermentation worth reading. They even introduced other types of fruit pulp into fermentation boxes and were able to really see the flavor change impact. Also, the importance of getting beans into fermentation boxes within 12 hours is also very important. Anyway, so many different opinions and theories out there...we all have so much to learn and it's all so much fun.

Altering post harvest practices can have a tremendous impact on the flavor of the beans - chances are his beans are of decent bean stock, and that it's the handling after growing that would be tweaked to get him something he's after. Age of beans (both from a maturity as well as how long it's been since they were 'picked'), disease state (especially in his part of the world), fermentation quantity, configuration, and protocol are immensely important, as is drying. If he's driving down to see the plantation, it's my very strongsuspicionthat whomever is providing him with beans isn't very well versed in post harvest control, and doesn't really know what 'levers' to pull to adjust the outcome. I assume you're working with Darin at UWI - he's great - just remember that he's got a very specific field of vision (WI specific), which has lots of history with their local govt's influencing things, and the origin has somepeculiaritiesthat would have me caution you on drawing too many parallels using the results from here to other origins.

In general, i'm of the opinion that it's a much smoother road to spend the time with your supplier(s) up front to direct the outcome so that 'fixing' it later doesn't have to be done. Some 'fixes' can be affected with processing, but it's a much tougher road to travel, and there's no guarantee of success!

Dear Panod,

Perhaps you could try to increase the temperature upto 75 degrees Celcius during the grinding for some 12-24 hours? You could use a hair dryer or some other device for this, but be sure the temp goes up!

Best

Rodney Nikkels

Thank you for all of your advices. It came out great, no sour or astringent taste at all! I roast the beans long enough that I can sense the changing of brownie smell turns to acidic smell and then back to brownie again. I let it conche for 34 hours, open the lid, blow in a little bit of air and hair dryer. Also added the Baking Soda. Despite it smelling like someone's smelly foot throughout the conche, I put it in the fridge and the next morning it ended up tasting good, bitter sweet.

Thank you Sebastian, thank you Richard, thank you Rodney! :D

And also my beans I brought them since October last year, and I just decided to buy a melanger so 4-5 months, I aged it a little bit too much. I think that this over fermentation of beans won't happen anymore. Thank you for all of your advices.

Best

Panod

Glad it worked! Since you pulled all the levers at once, it's hard to say which one did it 8-)

Letting dry beans age for 5 months is actually very, very good for the beans. Don't worry about that (as long as you stored them properly)

It does? But I have a feeling I might store it wrongly, I put it in this plastic tank, and put in some coal and those packets that absorb moisture and smell, and occasionally when it's sunny and dry outside I bring the beans out to dry (does this consider as aging?) Strangely every time when I open the lid to get the cocoa beans out, the temperature is noticeably cooler inside. Some beans have this white color covering it. After I roast the beans, some are loose, some are tight together, and some have this powdery texture (I always throw this beans with powder out) Is it usable?

Sorry that my question doesn't seem to end :S

Hard to say exactly not knowing your storage conditions, but chances are the white powder is either yeast or mold. Pretty normal, i'd not be overly concerned unless it's fuzzy.