Iodine Starch Reaction: Normal Pharmacy Iodine Work?

[biertourist]

During a particularly low diastatic power mash 2 weeks ago (Munich Dunkel) I realized that I didn't have more home brew shop iodine product so I walked next door to the pharmacy and purchased normal pharmacy iodine product (both products are only 1% or 1.5% iodine anyway).

-This is still going to work ok for testing starch conversion, right?


Adam

 

[ShaineT]

You'll still see black if starch is present. Test it out shortly after "dough in"(3 to 5 minutes) and you should see dark blue/purple.

 

[HeyNoPie]

Sounds right to me. I didn't realize there was a 'home brew shop iodine'.

 

[biertourist]

Yup. Works just like the other stuff.
(Just tried it.)

Adam

 

[ShaineT]

Yup. Works just like the other stuff.
(Just tried it.)

Adam

Nice. I use iodine swab packets. Just rip, fold and squeeze out a drop.

 

[DSmith]

Sounds right to me. I didn't realize there was a 'home brew shop iodine'.

I used Iodophor sold at LHBS and dilluted it with rubbing alcohol (isopropyl alcohol) in an eyedropper bottle [1 part of idophor (1.6% iodine) to 5 parts volume of isopropyl alcohol]. The dillution makes the solution lighter in color and very easy to see the reaction to black/purple with starches. Use white sidewalk chalk or drywall scraps.

The starch test has been a great indicator for decoction mashes, low temperature mashes and low diastatic power mashes (Munich Dunkel). It doesn't work well with mashes with roasted malts because the color changes are hard to see.

 

[ShaineT]

I used Iodophor sold at LHBS and dilluted it with rubbing alcohol (isopropyl alcohol) in an eyedropper bottle [1 part of idophor (1.6% iodine) to 5 parts volume of isopropyl alcohol]. The dillution makes the solution lighter in color and very easy to see the reaction to black/purple with starches. Use white sidewalk or drywall scraps.

The starch test has been a great indicator for decoction mashes, low temperature mashes and low diastatic power mashes (Munich Dunkel). It doesn't work well with mashes with roasted malts because the color changes are hard to see.

Good tips! I'll have to save some drywall scraps now. I usually just use a small white dish.

 

[Misplaced_Canuck]

It doesn't work well with mashes with roasted malts because the color changes are hard to see.

You can dilute the mash liquid with fresh water THEN test it.

MC

 

[DSmith]

You can dilute the mash liquid with fresh water THEN test it.

MC

Good idea. Those dark beers have typically been mashed high enough I'd skip the iodine test. I've used it mostly for low temperature mashes and decoctions.