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Impromptu LM pH data (Temp)

mwilson's picture
mwilson

Impromptu LM pH data (Temp)

Day

Cycle

Leavening

Arrival

Feed

  Temp (°C)Time (hrs)TimepHFeed ratioFed pH
11171410:304.081:14.92
12293.514:004.321:1.15.07
13293.517:304.231:15.01
14293.521:004.22*a 
        
24171411:003.991:14.77
2529415:004.221:14.99
2629419:00n/a1:1n/a
        
47123809:004.101:14.90
58122409:004.111:14.92
5929413:004.261:14.99
51029417:004.281:15.00
510a29421:004.171:1 
        
6111716.509:303.971:14.84
612294.514:004.111:14.88
61329418:004.281:14.99
613a29422:004.24*b 
        
714171913:003.931:1.55.01
71529417:004.291:15.02
715a29421:004.09  
        
816161811:003.901:1.55.06
81729415:004.161:1.14.97
81829419:00   
        
91916&124&2019:004.021:1.24.95
102029500:004.071:14.85
        
112117&128&2610:003.921:1.54.94
112229414:004.231:1.25.04
112329418:004.241:1.15.07
1123a294.522:304.12  
        
122417     

*a Unfed and loosely bound.
*b Abandoned

Notes:
Aromas:

15a - Mild alcohol aroma when cut into. Knowingly not mature, but proceeded to making an enriched dough anyway. Too much rye bread smell.
17 - Most elevated alcohol aroma so far in this process (although not quite how I remember how it should be, needs to be fruitier, cleaner, sweeter). Strong "honey" aroma, which is a good sign!

----

All overnight cold / cool temperature maintenance was done using the binding method, which was followed by a bagnetto / lavaggio (soaking / wash) step prior to the morning feed.

Probably not interesting...

DanAyo's picture
DanAyo

Is it correct to assume the fermentation temp is 80F?

mwilson's picture
mwilson

More like 83-85°F, 28-30°C.

I've updated the table with more data. First primo was binned, LM was not ready. Second one is doing well.

YenForYang's picture
YenForYang

Lots of questions:

Was there any particular reason you abandoned (*b) the LM on day 6 (i.e. was it accidental or intentional)?

What is the purpose of (*a) -- that is, not feeding and loosely binding? Was there any particular reason you decided to do this?

What does the "a" for the cycles 10a, 13a, 15a and 23a mean? Why did you choose not to feed these "a" cycles [I say this because I noticed that, for example, the time gap between 13a and 14 is 15 hours (not 19, which is the leavening time shown, implying that you fed cycle 13, not 13a)]

Does 12 C storage negatively impact the LM? Just wondering because I've seen most note that a "night rest" is to be done @ 16-18 C. There must be a lower limit, right, since I've read that prolonged low-temp storage (e.g. 4 C) isn't so good for the LM. 

I see you sometimes use ratios other than 1:1 -- i.e. 1:1.5, 1:1.2, etc. Are there particular cases/scenarios where you use these ratios, or did you just happen to add more flour for those particular cycles? (For instance, you seemed to only use the greater feed of 1:1.5 for the first refreshment, but that may be simply a coincidence.) 

Any guesses as to why cycle 17 had the "most elevated alcohol aroma so far in this process"? What is the "strong "honey" aroma" a good sign of? Why is a "fruity", "sweeter" aroma a good thing (just wondering, because I recently read this article , titled "What Makes Sourdough Smell Sweet and Why is it Bad for Baking?")

Is there a more-or-less "optimal" arrival pH and fed pH? Does it differ for longer night rest feeds and shorter refreshments?

Is your choice of 3.5, 4, 4.5, and 5 hour refreshments arbitrary (or for testing purposes only), or is there some other rule you followed?

Thanks.

mwilson's picture
mwilson

Hello,

The data above is simply a record of what occurred, driven mostly by intentional experimentational decisions, but some parts also as a matter of convenience.

Where I was using feed ratios higher than 1:1, they were driven by the intention to elevate the pH.

All feed cycles suffixed with an ‘a’ are in essence levains or feed builds intended to be inoculums for panettone dough. Hence, some were abandoned where I felt they weren't worth proceeding with. 

Denoted with a* where that build was not fed was possibly due to convenience, but I will add doing this is a good way to ensure the yeast cycle can be maximised while limiting acid development.

12C is fine, but things do move slow... There is an importance to keeping the LM no lower than 10C, as below this temperature fermentation is not optimal and dormancy will occur.

Regarding ‘Sweeter’ as a characteristic I was strictly referring to the aroma only, not the taste. The article you link is interesting, but we are discussing LM and not your run-of-the-mill starter.

However, I absolutely agree that no starter and especially a LM one should not taste sweet! Since this means unfermented...

In the grand scheme of things fruity is in no way a bad thing... It really signifies advanced yeast fermentation. Unfortunately, the author of that piece makes no distinction between sweet taste and sweet aroma, which are determined by separate processes. 

Where I chose longer fermentation times was driven by the importance of ensuring full tripling of the dough.

Optimal fed pH should be between 4.8-5.0 and arrival 4.0-4.1 for a mature LM. This is based on the data recorded by Thomas Teffri-Chambelland.

Think I've covered all your questions there...

 

Hope that helps.

Michael