Karo reduced 20PPM should be more "light beer" color, not orange.
Be careful though because, depending on what you're using for you manufacturing container or perhaps what you're using (glass) to observe the color, glass can add a tint to it, especially Mason jars. That is CHEAP glass. They make it thicker so it survives the temperature excursions that canning inflicts on the containers. You can't really see it but there is a slightly yellowish tinge to this glass and then too, with the thing being slightly curved with four very curved corners, it can cause all kind of color "artifacts".
Put some in a clear normal glass or a shot glass and look at the color there.
Maltodextrin (NOT Karo!) is longer chains of glucose molecules where only one end of that chain can reduce. THIS is why its a much better stabilizer. The longer chains of glucose tend to cause the color to get a little darker but not substantially but noticable.
Karo is a mix of glucose and maltose. Maltose, also know as malt sugar is a disaccharide just like table sugar (sucrose). That means its two molecules of glucose joined at the hip (wink) - you get what I mean.
Maltodextrin chains are always much longer than 2 molecules. Maltodextrin is typically composed of a mixture of chains that vary from three to 17 glucose units long.
Maltodextrins are classified by DE (dextrose equivalent) and have a DE between 3 and 20. This number is the glucose equivalency. Its a percentage. Glucose is 100%. Maltodextrin varies from 3% to 20%. That means even at its shorted length, its only 1/5 as effective, weight for weight, compared to glucose.
So you can see how you'd need MORE Maltodextrin to do the work of glucose.
The issue is, unless you can find a source for maltodextrin that sells single DE rated maltodextrin (you can in Europe apparently - a friend who makes Colloidal Silver got single DE number maltodextrin) what you get is mixed bag - a random mix of maltodextrins with various DE numbers.
For sure, Carbogain which many use is mixed bag. The maltodextrin you'd get from a beer/wine homebrewing supply shop is just as mixed bag. Cheap though. When I bought a pound (4 or 5 years ago), it was about $3 US.
The numbers I posted earlier in this post came from the last post on page 2 of this topic (in case the link doesn't take you there):
https://www.cgcsforum.org/index.php?topic=2546.msg21231#msg21231The number for maltose is for worst case (17 glucose units). This will cover everything since you have no clue what the average DE number of what you have is. Sure, you could be using much more but without knowing the DE number the only thing you can assume is worst case.