This is concord grape. I had about 2 pounds or more of these bunches about a week before the first frost hit us. Then I waited for the second batch, which I made the morning right after the first frost (a friend's mother-in-law told me they taste better after frost).
1 big colander is equivalent to more than a pound of them, but I had to wash, remove the green ones (choose only the most purple ones) to make into grape jelly.
5 cups prepared juice (about 3-1/2 lb. fully ripe Concord or you may use other loose-skinned grapes)
1-1/2 cups water
1 box Fruit Pectin (Sure-Jell or Ball Brand)
1/2 tsp. butter or margarine (optional)
7 cups sugar, measured into separate bowl
Preparing the juice:
STEM and crush grapes thoroughly, one layer at a time. Place in large saucepan; add water.
Bring to boil. Reduce heat to low; cover and simmer 10 minutes, stirring occasionally.
Place 3 layers of damp cheesecloth or jelly bag in large bowl. (I had none at the time. I improvised using a clean old pillowcase with a small cheesecloth sandwiched inside.) Pour prepared fruit into cheesecloth.
Tie cheesecloth closed; hang and let drip into bowl until dripping stops. Press gently (If you squeeze hard, you might end up with turbid jelly). Measure exactly 5 cups prepared juice into 6- or 8-quart saucepot.
(I did this juice preparation at night and let it drip overnight. Then I proceeded with the next step the next morning)
Making the jelly:
BRING boiling-water canner, half full with water, to simmer. Wash jars and screw bands in hot soapy water; rinse with warm water. Pour boiling water over flat lids in saucepan off the heat. Let stand in hot water until ready to use. Drain well before filling.
STIR pectin into juice in saucepot. Add butter to reduce foaming, if desired. Bring mixture to full rolling boil (a boil that doesn't stop bubbling when stirred) on high heat, stirring constantly.
Stir in sugar all at once and keep on stirring until dissolved.
Return to full rolling boil and boil exactly 1 minute (set the timer!), stirring constantly. This is how a full rolling boil looks like, where any stirring won't keep the bubbles down (hence, if the pot is not big enough, it might overflow). After one minute, remove from heat.
Skim off any foam with spoon.
Ladle into the hot jars.
Wipe with damp paper towel the sealing surfaces.
Pick the lid and screw band submerged in boiling water using the magnetic picker, then cover the jars and close, fingertip-tight.
Turn upside down for 5 minutes then turn upright again (this is when you want to eliminate processing in boiling-water canner for 5 minutes).
Set them on a place without disturbing for at least 12 hours. Then watch out for covers that did not pop in (downward concavity). If there's one, or if a jar is not full like in the upper small jar in this phot, place in the fridge and consume immediately, preferably within 2 weeks.
Children like it on sandwiches, I like it on Ritz or saltine crackers, hubby likes it (and raspberry and strawberry jams) with peanut butter for sandwiches. It is quite a bit sour for my taste, but my hubby and in-laws like the contrast of sweetness and tartness (maybe because they are used to these sour berries and grapes). One thing for certain, these home-made jams and jellies are far superior than the commercial ones.
(To my Filipina readers/friends in the Philippines who might be interested in making home-made preserves, a web research lead me to this site which gives the telephone number for the pectin producer in the Philippines and globally.)