Lactic Acid in Stawberry Rhubarb Saison

[Heatwaves]

This month's Zymurgy mag has an interesting article for a Strawberry Rhubarb Saison. However, the base wort mentions lactic acid as an ingredient without any quantity. I've never used lactic acid before, so how much would you use? It's also odd that it's in the "base wort" section. Isn't lactic acid typically added to the bottling bucket or secondary?

Here's the base wort and additional instructions. Any lactic acid advice would be greatly appreciated.

Base Wort

4.5 lb pale 2-row malt
4.5 lb red wheat malt
8 oz 10L caramel malt
0.85 oz Liberty hops @ 60 min
0.25 oz Liberty hops @ 15 min
Lactic Acid
Antifoam
Yeast Nutrient
Whirlfloc

Mash grains at 152F for 60 min.

Pitch 750 ml yeast starter of Wyest 3711 French Saison yeast. Ferment in primary for 3 weeks at 72F. Simmer 4 lb of frozen strawberries and 3 lb frozen rhubarb and add to secondary. Ferment in secondary for 3 weeks at 68F. Move to tertiary for 5 days.

So with these instructions in mind, how much lactic acid to use and when?

Thanks!

 

[tgmartin000]

Seems like it just might be used to adjust mash pH. In which case, you need to know about your water.

 

[Heatwaves]

Thanks. I researched it a little more and it definitely seems like the lactic acid is intended for the sparge water. I've never had to lower the pH of my sparge water in the past, so I'm just going to remove that step.