would this be good for making gummy bears?

Yes, very much so unless you're making sour gummy bears with the addition of citric or magic acids for extra tartness then you'd want to use a high methoxyl pectin that set a better in very high acid foods.

Does this contain the calcium needed to activate the gelling or am I required to purchase it separately?

No , it does not contain calcium to activate it as I found out after I purchased it. Buy Pomona's Universal Pectin which comes with calcium and comprehensive instructions. It is available in many health food stores.

What is the maltodextrin derived from? Need to know for gluten-free cooking.

Maltodextrin is derived from corn. This product is gluten free.

What is the sugar content in a tablespoon? Why does amazon say it is derived from citrus fruit and a question answered below said corn?

I can't determine from the package what the source is. But there is a phone number (888) 578-3932 for the distributor Modernist Pantry. Also a link for Kitchen Alchemy offering info http://ur.cool/blog

ASIN	B07T76HZFD
Best Sellers Rank	#114,265 in Grocery & Gourmet Food ( See Top 100 in Grocery & Gourmet Food ) #53 in Cooking & Baking Pectins
Customer Reviews	4.6 4.6 out of 5 stars (11)
Is Discontinued By Manufacturer	No
Manufacturer	Modernist Pantry
Product Dimensions	0.5 x 4 x 6.5 inches; 1.76 ounces
UPC	852473004630
Units	1.00 Count

Pectin - Amidated Low Methoxyl ⊘ Non-GMO Vegan OU Kosher Certified - 50g/2oz

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