Pete is right. Butter weighs in on the PH scale around 6.5; technically acidic, but, close enough to neutral that its not going to make a measurable difference in the overall acidity of the sauce.
Now, about those San Marzano tomatoes.......
Here's are some San Marzano fun facts that most people, not even many pros, know about.
According to the President of the "Consozio San Marzano", which is like the "Vatican" of San Marzano tomatoes, only 5% of the tomatoes sold in the US as "San Marzano" tomatoes are true San Marzano tomatoes grown in the Valley of Sarno outside of Naples. The rest are fake, even the ones that have the D.O.P. seal on the label. Why? Because Italian growers will ship the "non-San Marzano" tomatoes to the US where they are canned and labeled. Since there are no US laws that restrict a US cannery from placing a D.O.P. seal on the label coupled with the fact that the D.O.P. does not have jurisdiction in the US, all fake San Marzano tomatoes sold in the US are going to have the D.O.P. seal. So, the presence of the D.O.P. seal alone cannot be trusted. However, that is not to say that all San Marzano's sold in the US are fake.
Here is how you can tell a fake can from a real can of San Marzano tomatoes. Take note that identifying a true can of San Marzano tomatoes is just as much about what is on the label as what is not on the label.
A true can of San Marzano tomatoes will
ALWAYS have the following on the label or these characteristics:
- The words
"Pomodoro San Marzano dell'Agro Sarnese Nocerino" will always appear on the label.
- A D.O.P. seal
- A "Conzorzio San Marzano" seal with a certification number written as "N°-xxxxxxx". The certification number is unique to that tin and it can be used to authenticate the product as true San Marzano tomatoes.
-
For Cento San Marzano tomatoes only: a 4 digit number will appear on the label in addition to the above criteria that tells the date and location the tomatoes were canned. The 4 digit number can be used to verify the can as authentic on the Cento or Consorzio San Marzano websites.
- A can of true San Marzano tomatoes is always 28oz. Never more. Never less.
- San Marzano's are always sold as "whole, peeled" or as fillets. Never anything else.
- Each can will contain one basil leaf.
- A 28oz can of true San Marzano's will sell for around $10 to $15 in the US, sometimes more. So, if it's too good to be true, there's a near 100% chance that it is.
- True San Marzano tomatoes are only available through a small number of Italian importers and restaurant suppliers.
Here are features that are never associated with a can of true San Marzano tomatoes.
- The words "organic" or "sauce" never appear on the label.
- Never diced, chopped, pureed or crushed.
- Never stewed or flavored.
- True San Marzano's are never sold in grocery stores or food clubs.
- Any missing features listed above.
The reality is that getting your hands on a true can of San Marzano tomatoes in the US is about as easy as getting true Kobe beef (well, maybe not that hard, but you get the point
). While its possible, its very, very unlikely. However, this is not to say that the tomatoes sold as "San Marzano's" are not good. Its just that they are not
as good, much like Wagyu Cattle grown in Texas. The bitter truth is that most people who think they are getting true San Marzano's are merely overpaying for just regular tomatoes.
I think Cento San Marzano tomatoes that sell for $3.89 a can in the grocery store are pretty darn good, if you ask me.
Thanks for reading.
Cheers!