bottles-jars Sterilizing polypropylene bottle caps

[PepperDoc]

I have a bunch of ferments going and I want to package some small bottles of hot sauce for gifts. I'd like the bottles to be stored at room temperature. Final pH will be less than 3.0.
 
I'm looking to buy these bottles/caps.
 
Planning to fill the bottles with sauce and then steam in a pressure cooker to sterilize. After that, I want to cap and shrink wrap.
 
Problem is I don't know how to sterilize the polypropylene caps. I think they'll deform in boiling water or pressure cooker. Should I use 70% isopopyl alcohol? Tripotassium phosphate? Any recommendations? 
 
 

 

[CaneDog]

Any recommendations? 

 
I typically either autoclave in a pressure cooker, boil, or use StarSan to sterilize/sanitize depending on the item and use.  Some of that plastic will hold up to 15 lbs pressure heat just fine, but much of what I use is lab supply which is more likely to be intended for autoclave.  
 
I'd recommend testing a bottle & cap (filled with just water) in the pressure cooker or boiling water (whichever method you plan to bottle) and see how it holds up.  If it doesn't, I'd probably use StarSan.
 
Or perhaps someone will have experience with that product and be able to tell you whether the lids will hold up to heat.

 

[salsalady]

Use the standard hot fill, invert, hold process as detailed on the making hot sauce 101 stickied thread.

 

[Walchit]

I use a q-tip with vinegar to wipe out the inside of each cap, and follow the instructions Salsalady pointed out.