First thing in the morning at Murdick’s Fudge the copper kettle gets heated up and filled halfway with water to check the day’s boiling point. Due to humidity and other vagaries of the barometric pressure the boiling point could be off a hair from the accepted 212 degrees Fahrenheit.

To the casual observer this might not mean much. But when cooking fudge it means a lot. A precise boiling point is a major component of the process; too much moisture means too gooey, too little means too hard. Neither is good for business.

Fudge may seem synonymous with summer and in many ways it is, with kids and parents (the main demographic is actually women ages 33 to 45) standing in line to watch and eat at all three Vineyard locations. But the holiday rush is heavy too.

To stay on top of the December orders a group of fudge elves keeps a careful eye on the process. Sabrina Scott, Marjorie Braithwaite and Carlene Douglas work up the orders, checking the list twice and then letting the fudge makers know what flavors to make and how much. On Wednesday this week, the orders were thick.

Pouring out the hot fudge to cool and be shaped on marble tables. — Mark Alan Lovewell

“On average we push out 100 to 200 boxes a day,” says general manager Mike McCourt.

Double Chocolate had the lead for a brief moment but S’mores soon beat it out for number one, with Peanut Butter Chocolate close behind and Chocolate Candy Cane riding hard down the stretch. Pumpkin and Eggnog were out of the money that day.

Ricardo Salmon places 17 pounds of sugar on the scale then adds it to the pot. For the next 15 to 20 minutes he will stir the pot by hand, a long wooden paddle his constant companion. When asked if he gets sore, he acknowledges he did during his first year on the job.

“But no more,” he says, an experienced hand now with five years under his belt.

Fellow fudge makers Daniel Ferguson and Davan Miller measure out more sugar and get ready for the next task, laying out the melted fudge on marble tables to be shaped into loaves. Davan is a relative newcomer to the fold, having started just two years ago. Most everyone else is approaching their first decade.

In a few weeks everyone will head to Jamaica for a much needed rest, returning again in April. But unlike Santa, who after parking his sleigh may look to kick back in the Caribbean, layered up in suntan lotion and Red Stripes, for these fudge elves Jamaica is home. In fact, Mr. McCourt’s whole staff, summer and winter, is Jamaican.

When asked if fudge is king back home like it is in New England, there is a universal shake of heads. Fudge was an unknown commodity for all the workers until they found their way to the Vineyard, most by word of mouth. For Davan that word was very close to home. His mother Doris has been working at Murdick’s for 12 years. They have a good working relationship, he says.

“Mom works the night shift, I work the day shift.”

Mr. McCourt says he used to hire college students, mostly from the Big Ten schools, as Murdick’s started out as a Michigan business on the shores of Mackinac Island back in 1887.

“But college kept starting earlier,” he said, with students leaving him stranded in mid-August. And, with the same employees returning each year the fudge production is seamless.

The business celebrates 40 years on the Vineyard this coming summer.

For Christmas in Edgartown, Murdick’s will take a short break from mailing fudge all around the world, and host an open house at the Edgartown store. There will be fudge to eat, of course, along with caramel and cheese popcorn, peanut brittle and taffy.

“And hot chocolate too,” Mike says, declaring it the best ever, comparing it to a fine sipping whiskey, rather than a lesser version you presumably chug. When asked what the secret is, he just smiles, a gesture similar to when asked what the Murdick’s secret ingredient is. “It’s made with fudge,” he says. “I won’t go any further than that.”

Visit the open house at Murdick’s Fudge, 21 North Water street in Edgartown, from 11 a.m. to 2:30 p.m. on Saturday, and 11 a.m. to 3 p.m. on Sunday.