VP Date Spot
The first 2 yeasts are Y1 (listed as max. alcohol 713) and Y83 (listed as max. alcohol 502). The full microbe list is: Y1 Y83 M23 Y64 L92 L52 Y90 L84 Y25 Y74 A86 Y9 L76 Y56 Y3 Y65 Y2 L5 Y19 Y81 Y67. It is possible that microbes further down the list have influence on the beer too. Tests that may be conclusive for this will be shown later.
Some early beer making results are (open kettle, ingredients all added at start):
| Spot | Recipe | Alc. | Mold | Vits. | Gluc. | Malt. | LactA. | Date | Grassy | Result |
| -2056, -660 | 10l 20m 80h | 1113 | 0 | 135 | 1 | 46 | 0 | 200 | 37 | Bitter |
| | 10l 10m 120h | 1259 | 0 | 88 | 1 | 180 | 0 | 202 | 42 | VP muddled |
| | 15l 120h | 1259 | 0 | 72 | 1 | 120 | 0 | 202 | 49 | VP Dry hint of Date |
| | 15l 135h | 1259 | 0 | 84 | 121 | 150 | 0 | 202 | 49 | Cloying |
| | 15l 126h | 1259 | 0 | 76 | 31 | 150 | 0 | 202 | 49 | VP hint of Date |
| | 15l 15b 123h | 1259 | 0 | 74 | 1 | 180 | 0 | 202 | 49 | VP Brown hint of Date |
| | 15l 41b 115h | 1259 | 0 | 68 | 1 | 152 | 0 | 202 | 49 | VP Black hint of Date |
I added Mold and Lactic Acid to this list to see if the microbes M23 and L92 could have any influence in the beer, however, this doesn't seem to be the case. Also I added Date and Grassy, because Y1 produces far more Date flavours than Y83, and Y83 produces relatively more grassy flavour than Y1. However, the Date and Grassy values are very consistent in this list.
Next I've run some tests to see whether the high alcohol in the beers could be made by Y1 and Y83 alone, or that other yeasts further down the list are adding to the result.
| Recipe | sealed | yeasts | Al | Co | Mo | Vi | Gl | Ma | La | CA | LA | AA | Ba | Or | Bn | Ch | Da | Ho | Nu | Ci | Ta | Gr | Na |
| 15l 120h | - | full list | 1259 | 22 | 0 | 72 | 1 | 120 | 0 | 0 | 0 | 0 | 89 | 52 | 22 | 13 | 202 | 144 | 52 | 17 | 45 | 49 | 46 |
| 15l 120h | @1500 | Y1 | 713 | 22 | 0 | 143 | 517 | 150 | 0 | 0 | 0 | 0 | 89 | 10 | 9 | 8 | 195 | 138 | 22 | 10 | 45 | 32 | 20 |
| 15l 120h | @1200 | Y1 Y83 | 757 | 23 | 0 | 138 | 473 | 150 | 0 | 0 | 0 | 0 | 90 | 10 | 9 | 8 | 195 | 138 | 22 | 10 | 45 | 35 | 20 |
These results show that Y1 and Y83 together are not capable of making a high alcohol beer.
Several more interesting things can be seen in the data. For the flavour data, it's significant that the Y1+Y83 combination does now show lower values in any of the flavours that in the batch with Y1 alone. Y83's recorded flavour stats are all equal to or lower than Y1's, with an exception for Grassy. The presence of Y83 in a batch doesn't prevent Y1 to do its work; this is most clearly seen in the Date flavour. Instead, Y83 rather performs additional flavour production where it can; this can be seen in the increase of grassiness.
Also interesting to note is that Y83 is capable of raising the alcohol in the beer from 713 to 757, while it's recorded max. alcohol is only 502. This means that a yeast does not simply "die" when the brew reached its max. alcohol, but that some other mechanism is applied to determine when a yeast stops working.
The difference in Color and Barley values is attributed to the slightly later addition of malt in the kettle with the higher color value.
I can think of 2 possible explanations the behaviour of 2 yeasts in a batch of beer: a) The first yeast of the list is given unlimited access to the vitamins and sugars in the soup, and when it's done the second microbe has its turn. b) The first yeast has already done its fermenting by the time the second one enters, and the second one only can work with the remainder when the soup suits its vitamin and sugar floors. In theory a) entry time of microbes is not important, but in theory b) it is very important. Other tests will be done to see what influence entry time has.
| 15l 120h | @900 | Y1 Y83 Y64 Y90 | 757 | 22 | 0 | 139 | 473 | 150 | 0 | 0 | 0 | 0 | 89 | 10 | 9 | 8 | 195 | 138 | 22 | 10 | 45 | 34 | 20 |
| 15l 120h | @600 | Y1 Y83 Y64 Y90 Y74 Y25 Y9 | 757 | 22 | 0 | 139 | 473 | 150 | 0 | 0 | 0 | 0 | 89 | 10 | 9 | 8 | 195 | 138 | 22 | 10 | 45 | 34 | 20 |
| 15l 120h | @400 | Y1 Y83 Y64 Y90 Y74 Y25 Y9 Y56 | 757 | 23 | 0 | 138 | 473 | 150 | 0 | 0 | 0 | 0 | 89 | 10 | 9 | 8 | 195 | 138 | 22 | 10 | 45 | 35 | 20 |
These results show no activity at all compared with the previous sealing time.
| 15l 120h | @200 | Y1 Y83 Y64 Y90 Y25 Y74 Y9 Y56 Y3 Y65 | 1259 | 23 | 0 | 70 | 1 | 120 | 0 | 0 | 0 | 0 | 90 | 52 | 22 | 13 | 202 | 143 | 52 | 17 | 45 | 50 | 46 |
There's the high alcohol showing up. The yeast resposible for it could be Y3 or Y65. If the data recorded for Y65 on the wiki are correct, Y65 can't be the cause of the high alcohol, since it's vitamin floor is too high (199). Y3 however is a very good candidate, having a low glucose and maltose floor (resp. 1 and 46), though its vitamin floor is yet unknown.
While making festival beers I noticed that a few of the kettles I dropped on the spot didn't produce the beer I was looking for. So, I placed 3 kettles each a coord away from the original spot and did some beers there. (KOrg is the kettle on the original spot.)
| Name | Spot | Recipe | Result | Microbe list |
| KOrg | -2056, -660 | 15l 126h | VP date | Y1 Y83 M23 Y64 L92 L52 Y90 L84 Y25 Y74 A86 Y9 L76 Y56 Y3 Y65 Y2 L5 Y19 Y81 Y67 |
| K1 | -2056, -661 | 15l 126h | VP date | Y1 Y83 Y64 M23 L92 L52 Y90 L84 Y74 Y25 A86 Y9 Y56 L76 Y3 L5 Y65 Y2 Y19 Y81 Y67 |
| K2 | -2057, -660 | 15l 126h | Cloying | Y1 Y83 Y64 M23 L92 L52 Y90 L84 Y74 Y25 A86 Y9 Y56 L76 Y3 L5 Y2 Y65 Y19 Y81 Y67 |
| K3 | -2055, -660 | 15l 126h | VP date | Y1 Y83 M23 Y64 L92 L52 Y90 L84 Y25 Y74 Y9 A86 Y56 L76 Y3 Y65 Y2 L5 Y19 Y81 Y67 |
The remarkable result here is that the microbe lists of K1 and K2 only differ in the last 5 places; yet they produce different results.
The stats of these beers were:
| Name | Al | Co | Mo | Vi | Gl | Ma | La | CA | LA | AA | Ba | Or | Bn | Ch | Da | Ho | Nu | Ci | Ta | Gr | Na |
| KOrg | 1259 | 22 | 0 | 76 | 31 | 150 | 0 | 0 | 0 | 0 | 89 | 52 | 22 | 13 | 202 | 149 | 52 | 17 | 45 | 49 | 46 |
| K1 | 1259 | 22 | 0 | 76 | 31 | 150 | 0 | 0 | 0 | 0 | 89 | 52 | 22 | 13 | 202 | 149 | 52 | 17 | 45 | 49 | 46 |
| K2 | 1239 | 22 | 0 | 78 | 51 | 150 | 0 | 0 | 0 | 0 | 89 | 52 | 22 | 13 | 202 | 149 | 52 | 17 | 45 | 48 | 46 |
| K3 | 1259 | 22 | 0 | 76 | 31 | 150 | 0 | 0 | 0 | 0 | 89 | 52 | 22 | 13 | 202 | 149 | 52 | 17 | 45 | 49 | 46 |
It might seem that it was coincedence that the beer in K2 didn't work out right, but the results with multiple beers in the same kettles are very consistent.
Next I carried out a number of yeast tests to determine microbe entry times. Only yeasts will be listed in the next table.
| Name | @1560 | @1542 | @1500 | @1450 | @1420 | @1400 | @1200 | @900 | @600 | @400 | @200 |
| KOrg | nt | nt | Y1 | nt | nt | nt | Y1 Y83 | Y1 Y83 Y64 Y90 | Y1 Y83 Y64 Y90 Y74 Y25 Y9 | Y1 Y83 Y64 Y90 Y74 Y25 Y9 Y56 | Y1 Y83 Y64 Y90 Y25 Y74 Y9 Y56 Y3 Y65 |
| K1 | - | - | Y1 | Y1 | Y1 | Y1 Y83 | Y1 Y83 | nt | nt | Y1 Y83 Y64 Y90 Y25 Y74 Y56 Y9 | Y1 Y83 Y64 Y90 Y25 Y74 Y56 Y9 Y3 Y65 |
| K2 | - | Y1 | Y1 | Y1 | Y1 | Y1 Y83 | Y1 Y83 | nt | nt | Y1 Y83 Y64 Y90 Y74 Y25 Y9 Y56 | Y1 Y83 Y64 Y90 Y74 Y25 Y9 Y56 Y3 |
| K3 | - | Y1 | Y1 | Y1 | Y1 Y83 | Y1 Y83 | Y1 Y83 | nt | nt | Y1 Y83 Y64 Y90 Y25 Y74 Y9 Y56 | Y1 Y83 Y64 Y90 Y25 Y74 Y9 Y56 Y3 Y2 Y65 |
Some yeasts seem to have switched places compared to the full microbe lists. The kettles have not been moved during the experiments. I noticed earlier that this happened too on other spots. I take it that these 2 microbes enter the kettle at exactly the same time in these cases.
More tests were done to determine the entry time of Y3 in K1, K2, and K3.
| Name | @400 | @375 | @350 |
| K1 | Y1 Y83 Y64 Y90 Y25 Y74 Y56 Y9 | Y1 Y83 Y64 Y90 Y25 Y74 Y56 Y9 | Y1 Y83 Y64 Y90 Y25 Y74 Y56 Y9 Y3 |
| K2 | Y1 Y83 Y64 Y90 Y74 Y25 Y9 Y56 | Y1 Y83 Y64 Y90 Y74 Y25 Y9 Y56 Y3 | Y1 Y83 Y64 Y90 Y74 Y25 Y9 Y56 Y3 |
| K3 | Y1 Y83 Y64 Y90 Y25 Y74 Y9 Y56 | Y1 Y83 Y64 Y90 Y25 Y74 Y9 Y56 Y3 | Y1 Y83 Y64 Y90 Y25 Y74 Y9 Y56 Y3 |
These results are not at all what I expected. I had expected a later entry of Y3 in K2, the kettle that produces less alcohol than the others. A later entry was found, but in K1, a kettle that behaved completely normal.
New data suggest that already earlier in the fermentation process of K2 something goes wrong. I did a batch of beer in K1, K2, and K3, used a recipe of 15l and 126h, and closed the kettle at 1400 seconds left. All 3 batches had both Y1 and Y83, and no other microbes.
| Name | Al | Co | Mo | Vi | Gl | Ma | La | CA | LA | AA | Ba | Or | Bn | Ch | Da | Ho | Nu | Ci | Ta | Gr | Na |
| K1 | 757 | 22 | 0 | 144 | 533 | 150 | 0 | 0 | 0 | 0 | 89 | 10 | 9 | 8 | 195 | 144 | 22 | 10 | 45 | 34 | 20 |
| K2 | 737 | 22 | 0 | 146 | 553 | 150 | 0 | 0 | 0 | 0 | 89 | 10 | 9 | 8 | 195 | 144 | 22 | 10 | 45 | 33 | 20 |
| K3 | 757 | 22 | 0 | 145 | 533 | 150 | 0 | 0 | 0 | 0 | 89 | 10 | 9 | 8 | 195 | 145 | 22 | 10 | 45 | 34 | 20 |
Since all the characteristic flavour data are present in K2 as in K1 and K3, the difference between K2 and the other 2 kettles must have been occurred during the phase where Y83 was present. The entry times for Y1 and Y83 are already pinned down fairly accurately (see above), so if there's an entry time effect it's very subtle!
Further tests on yeast entry times still didn't help to solve the mystery of the 20 missing alcohol:
| Name | Entry Y1 | Entry Y83 | Entry Y3 | Y1 present alone during | Y83 present alone during |
| K1 | between 1530-1520 | between 1405-1400 | between 375-350 | 115-130 sec | 1025-1055 sec |
| K2 | between 1550-1542 | between 1405-1400 | between 400-390 | 137-150 sec | 1000-1015 sec |
| K3 | between 1550-1542 | between 1430-1420 | between 400-390 | 112-130 sec | 1020-1040 sec |
No differences in entry time of Y83 in K1 and K2 could be detected. There seems to be a slight difference in the time that Y1 spends alone (i.e. before entry of Y83) in the kettle. The question comes up whether the missing alcohol can be linked to the Y1 phase. Making a batch of beer and closing the kettle before Y83 enters can shed no light on this, since single yeast beers always yield the full potential of the yeast, given enough nutrients. But when I look at the flavour data of the beer batches with Y1 and Y83 present, I see that the Date flavour in all 3 kettles reaches its maximum. If one kettle produces 20 alcohol less (2-3%) I would expect to see the Date flavour value 2-3% lower too. The time Y83 spends alone in the batch (i.e. the time between the moment Y83 enters and the moment Y3 enters) can have no influence either, since 20 alcohol is missing from K2 also when the kettle is sealed immediately after Y83 enters. So the mystery of the 20 missing alcohol remains unsolved for now.
The time table though still shows interesting data. Y1 spent an undisturbed period of 92-150 seconds in the kettles, and this was enough for Y1 to reach its maximum alcohol and flavour values. This seems a rather short period of time.
Amtep's Working Together Apart model
However, Amtep pointed out to me that there IS a possibility that both yeasts are active at the same time, if we take into consideration that fermentation works in discrete steps, and that steps are either not started, or completed fully.
The
Fermentation Tick theory decribes the way in which yeasts produce ever increasing amounts of alcohol in steps, until they run out of nutrients or they reach their alcohol ceiling.
The steps for both Y1 and Y83 would run as follows:
| Tick | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Alc. produced | 10 | 14 | 20 | 28 | 39 | 55 | 77 | 108 | 151 | 211 |
| Tot. alc. after | 10 | 24 | 44 | 72 | 111 | 166 | 243 | 351 | 502 (Y83 ceiling) | 713 (Y1 ceiling) |
The missing 20 alcohol in K2 can be explained by Y83 stopping short at tick 2, while in K1 and K3 Y83 peforms tick 3 too.
Above, I already explored the possibility that Y1 has finished at the point that Y83 enters, or that Y1 delays Y83's activity until the former yeast is finished, but this didn't really give a satisfactory explanation of Y83 performing fewer steps in K2.
What Amtep pointed out is that another scenario exists, when Y83 becomes active when Y1 has either completed tick 5 or 6. This is what could have happened in K2:
| Tick | Yeast | Alc. before tick | Alc. by Y1 | Alc. after Y1 | Alc. by Y83 | Alc. after tick | notes |
| 5 | Y1 | 72 | 39 | 111 | - | 111 | Y1 only is present |
| 6 | Y1 | 111 | 55 | 166 | - | 166 | Y1 only is present |
| 7 | Y1 + Y83 | 166 | 77 | 243 | 10 | 253 | alcohol allows a tick by each of the yeasts |
| 8 | Y1 + Y83 | 253 | 108 | 361 | 14 | 375 | alcohol allows a tick by each of the yeasts |
| 9 | Y1 + Y83 | 375 | 151 | 526 | 0 | 526 | 526 is over Y83's alcohol ceiling, so only Y1 activity |
| 10 | Y1 + Y83 | 526 | 211 | 737 | 0 | 737 | 526 is over Y83's alcohol ceiling, so only Y1 activity |
| 11 | Y1 + Y83 | 737 | 0 | 737 | 0 | 737 | 737 is over Y1's alcohol ceiling, so no activity at all |
On the other hand, a slightly different sequence could have happened in K1:
| Tick | Yeast | Alc. before tick | Alc. by Y1 | Alc. after Y1 | Alc. by Y83 | Alc. after tick | notes |
| 5 | Y1 | 72 | 39 | 111 | - | 111 | Y1 only is present |
| 6 | Y1 + Y83 | 111 | 55 | 166 | 10 | 176 | alcohol allows a tick by each of the yeasts |
| 7 | Y1 + Y83 | 176 | 77 | 253 | 14 | 267 | alcohol allows a tick by each of the yeasts |
| 8 | Y1 + Y83 | 267 | 108 | 375 | 20 | 395 | alcohol allows a tick by each of the yeasts |
| 9 | Y1 + Y83 | 395 | 151 | 546 | 0 | 546 | 546 is over Y83's alcohol ceiling, so only Y1 activity |
| 10 | Y1 + Y83 | 546 | 211 | 757 | 0 | 757 | 757 is over Y83's alcohol ceiling, so only Y1 activity |
| 11 | Y1 + Y83 | 757 | 0 | 757 | 0 | 757 | 757 is over Y1's alcohol ceiling, so no activity at all |
This model shows that the higher alcohol level is produced in the kettle where Y1 gets to spend less time alone. And that is exactly what my entry time data for Y1 and Y83 shows.
The model presented above makes the assumption that Y83's alcohol ceiling is checked after the results of Y1's tick are added up to the total alcohol. So there is a variation to the model possible where both yeasts check the alcohol level at the start of the tick, and this would lead to a slightly different time schedule.
For K2:
| Tick | Yeast | Alc. before tick | Alc. by Y1 | Alc. by Y83 | Alc. after tick | notes |
| 5 | Y1 | 72 | 39 | - | 111 | Y1 only is present |
| 6 | Y1 | 111 | 55 | - | 166 | Y1 only is present |
| 7 | Y1 | 166 | 77 | - | 243 | Y1 only is present |
| 8 | Y1 + Y83 | 243 | 108 | 10 | 361 | alcohol at start allows a tick by each of the yeasts |
| 9 | Y1 + Y83 | 361 | 151 | 14 | 526 | alcohol at start allows a tick by each of the yeasts |
| 10 | Y1 + Y83 | 526 | 211 | 0 | 737 | 526 is over Y83's alcohol ceiling, so only Y1 activity |
| 11 | Y1 + Y83 | 737 | 0 | 0 | 737 | 737 is over Y1's alcohol ceiling, so no activity at all |
And for K1:
| Tick | Yeast | Alc. before tick | Alc. by Y1 | Alc. by Y83 | Alc. after tick | notes |
| 5 | Y1 | 72 | 39 | - | 111 | Y1 only is present |
| 6 | Y1 | 111 | 55 | - | 166 | Y1 only is present |
| 7 | Y1 + Y83 | 166 | 77 | 10 | 253 | alcohol at start allows a tick by each of the yeasts |
| 8 | Y1 + Y83 | 253 | 108 | 14 | 375 | alcohol at start allows a tick by each of the yeasts |
| 9 | Y1 + Y83 | 375 | 151 | 20 | 546 | alcohol at start allows a tick by each of the yeasts |
| 10 | Y1 + Y83 | 546 | 211 | 0 | 757 | 546 is over Y83's alcohol ceiling, so only Y1 activity |
| 11 | Y1 + Y83 | 757 | 0 | 0 | 757 | 757 is over Y1's alcohol ceiling, so no activity at all |
The main difference between the two variations of the model is timing. Which version of the model is correct, depends mainly on the tick length during the fermentation process. When combining the modeled time schedule with the data from the yeast entry table, the first version (i.e. separate alcohol ceiling checks) uses a tick length of 22.8-26 seconds; and the second version (i.e. alcohol ceiling checks at tick start) uses a tick length of 19.2-21.7 seconds. It's reasonable to assume that tick length must either be 20 or 24 seconds, which are both "nice" numbers.
Y3's behaviour can be added to this model too. It enters late into the kettles, between 350-400 seconds left, so it is highly unlikely that it is active at the same time as the other yeasts. Y3 needs 9 ticks to make 502 alcohol to raise the total alcohol to 1239/1259. If the tick length for Y3 is the same as for Y1 and Y83, it's entry time leaves enough time to complete those 9 ticks.
Y3's alcohol ceiling is listed as very high (1421). But if we follow the fermentation tick theory, the alcohol level in a pure culture of Y3 after tick 8 is only 1008. The actual Y3 alcohol ceiling value therefore can be any value between 1009 and 1421. So it's reasonable to assume that 1239/1259 is over Y3's alcohol ceiling, and that Y3 stops activity after the brew reaches that alcohol value.