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edits
Changes
added summary interpretation of hte charts
In the case of the "0 minute" boil, approximately 175 µg/L of SMM is converted into approximately 20 µg/L of DMS. Just as in the other examples, the DMS continues to volatilize below boiling temperatures in an open cooling system (see [[Dimethyl_Sulfide#Volatility_of_DMS|DMS Volatility]]). Even if the wort was cooled in a closed system and this amount of DMS was retained in the wort, 20 µg/L of DMS is still below the recommended threshold of 100 µg/L of DMS that should be allowed to enter the fermenter <ref name="Scheuren2016mbaa"></ref>.
For comparison sake, a graph of a 60 minute boil is shown below, again with an "open cooling" system that allows continued evaporation of DMS during the cooling period. Note that in a closed cooling system, the point on the graphs where the boiling times stop is approximately how much DMS is estimated to remain (DMS will continue to volatilize off if cooled in an open system, but not in a closed system). In the case of cooling in a closed system and assuming a fast cooling rate in the ranges where SMM is quickly converted to DMS, the 60 minute boil predicts ~15 µg/L DMS, the 15 minute boil predicts ~35 µg/L, the "0 minute" boil predicts ~20 µg/L DMS, and the 15 minute pasteurization predicts ~5 µg/L:
[[File:DMS 60Minute.png|none|thumb|500px|SMM conversion to DMS during a 20 minute heat up, 60 minute boil at 100°C, and 60 minute cool down to 20°C. Graph created and provided by [https://www.facebook.com/mark.hammond.1253 Mark Hammond].]]
In an open cooling system, which the graphs assume, DMS continues to volatilize off. In a closed cooling system, the points on the graphs where the boiling/heating stops and the cooling begins, are the points where DMS amounts will remain. If the cooling rate is slow to begin and the wort is held within the 90-100°C range for an extended period of time (for example in the case of whirlpooling), more DMS will continue to accumulate. Assuming the wort is quickly chilled, the table below shows a summary of the predicted DMS in the above tables:
{| class="wikitable"
|-
! Boil Type !! µg/L DMS into Fermenter (closed cooling) !! µg/L DMS into Fermenter (open cooling)
|-
| 15 Min Pasteurzation at 82°C/180°F || ~5 || ~2
|-
| 15 Min Boil || ~35 || ~5
|-
| "0 Minute" Boil || ~25 || ~5
|-
| 60 Minute Boil || ~25 || ~0
|}
In summary, the new model predicts that the 15 minute pasteurization rest produces the least amount of DMS (~5 µg/L), while the 15 minute boil produces the most DMS (~35 µg/L). Note that 35 µg/L of DMS is still below the recommended 100 µg/L of DMS that should be allowed to go into the fermenter <ref name="Scheuren2016mbaa"></ref>.
===Kettle Souring and Effects of pH===