Factor Affecting Bread Toasting Speed?

So, to change the mood to something less serious: I toasted some raisin bread and forgot to reduce the heat setting on my toaster. It came out almost burnt. Far darker than the normal whole wheat toast I make. At the same setting the WW is lightly toasted.

Although my example is raisin bread, I’ve noticed that other breads like Italian-style also toast faster.

It got me to wondering:
*What is about certain bread types that cause them to toast so variably at the same heat settings? *

The raisin slice did not seem to be any less thick or weigh much less than my regular whole wheat, but TBH, I didn’t measure or weigh so it could be that.

Alternatively, I’m wondering if it’s some component of the flour or some other ingredient like added sugar?

Just curious - Any humble opinions?

I’m going with sugar content.

Seconding Beck’s reply, sugar.

Moisture too, it won’t toast if it isn’t dry enough.

CMC fnord!

Also density; the denser the bread, the longer it is likely to take to toast.

If anything affects pH, IIRC browning is faster at higher pH.

The original darkness of the toast. White takes longer than brown, etc. Raisin bread is generally a bit darker, at least.

If you ever watch the color change while toasting you’ll note there’s no color change for quite a while and then whoop, it starts darkening quickly.

The combination of the heat maxing out, the toast starting to darken, etc. makes toaster design a lot harder than it looks. At one point the toast is lightly brown and a few seconds later it’s on the verge of burning.

A lot of the “oops done!” effect is moisture. It will take a while to evaporate and take a lot of energy to do so, and when it’s done, “boom, toast!”.

The Miracle of Moisture Management.

I recall Dave Arnold wanting to title a forthcoming book as such, but his editor said no.

Light-colored bread toasts slower than darker bread. Most of the energy in a toaster is optical - IR from the heating elements. A darker surface absorbs this much better than a lighter one, so a pumpernickel bread will that much faster than white bread.

IME, raisin bread has more moisture than plain bread. So the OP would find that the toast would come out underdone rather than overdone if this was the factor.

I agree it’s part of the equation, but not as much as color.

I wasn’t thinking of color at all myself, and believe you are right that dark toasts faster, but I still think moisture is to blame for the sudden shift from “why isn’t it toasted” to “how did it suddenly burn?”

Interesting discussion, thanks.

I’m not so sure about the bread colour factor. My raisin bread is much much lighter and toasts way faster than the whole-wheat I’m comparing it to.

I’m leaning toward the sugar level in the bread.

If you want to see something char with ease, try Sweet Bread.