Bob and Maria, young newlyweds, were excited about preparing some food for a friend’s Labor Day weekend potluck. 

Both considered themselves good cooks, but neither had actually prepared anything for a potluck on a hot summer day. No problem, they told each other, what could be different from what needs to be done any other time of the year. After all, they both considered themselves to be people who kept a clean house. And since Bob’s mom was a nurse, they had plenty of advice about washing their hands before and after preparing food.

Then came Aunt Sylvia. Maria first encountered her when she went into the kitchen and saw the mystery aunt putting some meat Maria was marinating in the refrigerator.

“What are you doing,” she asked the woman politely.

“No problem,” said the woman, who identified herself as Aunt Sylvia. “You should just always marinate meat in the refrigerator. Keeping meat out at room temperature runs the risk of having it contaminated with dangerous bacteria?”

“But my kitchen is clean,” said Maria.

“Oh yes,” agreed Aunt Sylvia, “but you never know if any dangerous bacteria such as E. coli are on the meat. At room temperature, they quickly multiply, and that can get people sick. Really sick. They’re so small, you can only see them with a microscope.”

Maria, being a polite person, thanked Aunt Sylvia for the advice.

Not long after that, Bob went into the kitchen and encountered Aunt Sylvia. She was pulling out another cutting board and another knife and placing them on another counter in the kitchen.

“Oh, we already have a cutting board and knife out,” he told her, pointing to the ones his wife had put on another counter in anticipation of cutting up some meat and some fresh vegetables and fruit.

“Yes, I saw that,” said Aunt Sylvia. “But you should never use the same cutting board and knife for meats and produce.”

“Really?” said Bob. “I thought as long as we were keeping everything clean that it would be okay.”

“Yes, many people think that,” said Aunt Sylvia. “But having clean hands, a clean cutting board, and a clean knife is just the beginning. You also have to keep meat and produce separated when you’re preparing them because meat, especially, can harbor pathogens that can cross over to the vegetables or fruit. That’s important to know if you’re going to serve the vegetables and fruit raw.”

Bob said “good to know, especially since everyone likes to nibble on raw veggies and fruit in the summer.”

“And you have to be really careful with cantaloupe,” said Aunt Sylvia, as she picked up a cantaloupe on the counter. 

“See the netting on the surface. Well, cantaloupe grows on the ground and dangerous pathogens such as Listeria can get on the surface, and the netting holds them there. That’s why you actually have to scrub a cantaloupe with a brush and running cold water before cutting into it. If you don’t, the knife can take any Lsteria that might be on the surface right into the flesh. This is serious stuff. During one Listeria outbreak back in 2011, cantaloupes contaminated with listeria sickened 147 people in 28 states, killing 33 of them. Many of people who became ill” had to go to the hospital.”

Holy cow,” said Bob. “This is, like you said, serious stuff.”

“Actually, you should wash all fresh fruits and vegetables if you intend to serve them raw,” Aunt Sylvia said. “And those like cucumbers that have hard skins should also be washed with a brush under cold running water. And that’s even if you plan to peel them. You don’t want to get any bacteria from the skins onto the knife because then the knife will contaminate the produce.”

Going on to another subject, Aunt Sylvia turned to him and asked: “Who’s going to be grilling the meat at the barbecue”

“My friend Edwin,” said Bob, with a big smile. “He’s a real pro. In fact, he’s even going to be grilling oysters. Maria and I have never had them. Is there anything we should know?”

“Yum,” said Aunt Sylvia. “I do love grilled oysters. But most people think that once they’ve opened, they’re ready to eat. Actually it’s best to keep them on the grill for another 15 seconds or so.”

“By the way, does he have a meat thermometer,” asked Aunt Sylvia.

“I’ve never seen him use one,” Bob said. “But he’s been doing it for a long time. I’m sure he knows what he’s doing.”

“He probably makes really good hamburgers and chicken she said. “But just for safety’s sake,” here’s a thermometer you can give him. She quickly pulled a thermometer out of her apron pocket.

“What will he be doing with it,” Bob asked, having never actually seen one being used before.

“He’ll poke it into the meat or chicken to test the temperature,” she said. “Hamburgers need to be 160 degrees to be safe to eat, and chicken needs to be 165 degrees. Any cooler than that, people can get Salmonella or E. coli, which can get them very sick.”

“But I like my burgers rare,” said Bob. “And so do a lot of other people. Even Maria.”

“Now that you know what I just told you, you might not want to eat your burgers anything but well-done,” said Aunt Sylvia. “But you can make your own choices about that. What’s important, though, is that children and older people shouldn’t be served meat that isn’t cooked to the right temperature. That’s because they’re particularly vulnerable to food poisoning. And no one wants to get their guests sick, no matter how old or young they are.”

Thinking of all of the children that would be attending the potluck, Bob took the thermometer out to the car and put it where he would be sure to remember to give it to Edwin.

Maria came back into the kitchen to check on the marinade.

“It’s looking good, isn’t it,” she asked Aunt Sylvia.

“Very good,” said Aunt Sylvia. “But do make sure that any marinade you use, or anyone else uses, doesn’t get put on the meat or chicken after it’s pulled off the grill?”

“Oh my goodness, why not?” asked Maria.

“Because as the meat is being grilled and the marinade is being applied to it, the utensil being used to do that comes into contact with the meat or poultry and from there it goes back into the marinade. That means that any bacteria on the meat can end up in the marinade. When the meat is cooked to the right temperature, it will be safe. But because the left-over marinade isn’t cooked, it can contaminate the cooked meat. Better to save some of he marinade you make before applying it to the meat or make some more and keep it separate to add to the meat once it’s cooked.”

“Simple enough,” said Maria. And she quickly made up another small batch of the marinade to take with them to the potluck.

As Bob started getting their coolers ready to take to the potluck, Aunt Sylvia watched him carefully.

“Best to keep the beverages and food in separate containers,” she said. “People are always opening coolers up to grab a beverage. By having just one cooler for beverages, the meat and other foods will stay cooler because that cooler is staying shut until someone actually needs the food.”

“I never thought of that,” said Bob. “But it does make sense.”

Aunt Sylvia told them this is especially important this time of year because foodborne bacteria multiply faster in warm weather – and the larger the dose of bacteria the more likely it will lead to food poisoning.

As Bob opened the trunk of the car to put in the coolers, Aunt Sylvia asked him how far away the potluck was going to be.

Only a few miles down the road,” said Bob.

“Well, then that’s OK,” she said. “But if you ever travel any distance with food, it’s best not to put the coolers in the trunk because in hot weather, especially on day’s like this when it’s 90 degrees or hotter, the trunk acts like an oven. Better to put the coolers up front.”

“Well, it certainly is hot today,” said Bob, wiping some perspiration off of his brow. “Maybe I won’t put them in the trunk after all.”

As Bob and Maria got into the car ready to start on their way, they asked Aunt Sylvia if she wanted to come along.

“Oh no,” she said. “I still have a lot of people I need to visit.”

As Bob was ready to start the car, she said, “Now make sure you stay out of the danger zone.”

The danger zone” said Maria, a worried tone in her voice. “Have there been any problems on the road.”

Oh no said Aunt Sylvia, chuckling. I was talking about the temperature danger zone for food. It’s anywhere between 40 degrees and 140 degrees.

Maria and Bob looked puzzled.

“It might be easier to understand if you think of it this way,” said Aunt Sylvia. “Keep cold foods cold — 40 degrees or colder — and hot foods hot — 140 degrees or warmer. Between those two temperatures is the danger zone.”

They both smiled. “That makes sense said Maria.”

“Oh, and don’t let food set out for any longer than two hours,” she said. “Although on days 90 degrees or above like today, they should be put in the refrigerator or back on the stove or in the oven after one hour. If they’re left out any longer, they should be thrown out, although I know that’s hard to do.”

“Good to know on a day like this,” said Bob.

On their way out of their driveway, they fondly waved goodbye to Aunt Sylvia.

“She’s a neat woman,” Bob said to Maria. “She certainly knows a lot. How is she related to you?”

“To me?” said Maria, shocked at his question. “I thought she was your aunt.”

They sat in stunned silence for a minute or so. Then they both started laughing.

“Well, we might not know who she is, but I think we should call her the ‘Ghost of Safe Summer Picnics, Present and Future.”

Maria seemed puzzled by that name at first, but she quickly saw the humor — and truth — in it.

“You’re right,” she said. “That’s the perfect name for her. We were so lucky to have her come visit us today. I wonder who she’s with now. She said she still had a lot of people to visit.”

“I imagine she does,” said Bob. “If they’re anything like us, they certainly have a lot to learn.”

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