STEM News: Ice Cream


Ice cream is an integral part of my life, especially in the summer time. It’s practically it’s own food group – there’s protein, grains, fruits/veggies, and ice cream.


I eat it more than I should, but not as much as I want. Sometimes, in an effort to be a little more healthy, I substitute Greek yogurt for ice cream. It’s almost as good (or so I tell myself), and a bit more healthy.

So I was talking about that on Twitter the other night (ice cream is THAT important in my life!), and it was brought to my attention that some areas of the United States are experiencing an ice cream shortage due to a recall. I vaguely remembered hearing about a recall a while back, but had no idea it was still affecting ice cream consumers. Sounds horrible!!

Being the ice cream connoisseur I am, I thought this would be the perfect news story for us to talk about from a STEM angle.

Here’s a great infographic from the CDC that describes the outbreak. Check it out. People got sick from a type of bacteria called Listeria that was found in Blue Bell ice cream.

Want to know what floors me the most?

Only 10 people in the entire United States (1 in Arizona, 5 in Kansas, 1 in Oklahoma, and 3 in Texas) were confirmed to be hospitalized over a period of five years, but that was enough for the Centers for Disease Control (CDC) to isolate the source of the contamination.

That’s incredible!

Think about how many people get sick across the country every day, every year, or every 5 years. To keep track of all those sicknesses and identify a trend from just 10 people blows my mind. Of course, there may have been more cases that weren’t linked, but still, that’s incredible!

Researchers who find these kinds of medical trends are called epidemiologists. Want to know how they found the problem in this case?

Scientists used genetic testing to look at the entire DNA sequence of the listeria of the people who were sick, and compared it to the entire DNA sequence of bacteria found in different Blue Bell ice cream samples. Most of the cases in this outbreak were actually linked to ice cream that people ate while already in the hospital. Talk about horrible luck!

The Blue Bell production sites had been inspected by the Food and Drug Administration (FDA) during the period that contaminated ice cream was being produced, but Listeria was not found during the inspection. There were other health violations, but I assume most factories have minor violations in routine inspections. I don’t know how major or minor the violations were in this case.

I’m certainly not an expert, but it seems like Blue Bell took the right steps throughout the investigation of the outbreak by voluntarily recalling different products as soon as they were linked to the outbreak. Eventually, they ended up shutting down their manufacturing facilities completely, leading to a major ice cream shortage in areas of the south. I feel for you, my friends, especially now that we’re in the thick of the summer heat!

Since genetically different version of Listeria were found in the different manufacturing facilities, and Listeria was not found during the routine FDA inspections, I’m not sure what the actual source of the contamination was, and whether each factory had the same contamination problems.

As I was doing a little more research for this article, I came across some really fantastic breaking news. Blue Bell is going to be back in stores at the end of this month. You heard it here first, folks!! (or it may have come from this news article, too). I hope by summer’s end, you’ll all have access to all the cold, creamy, delicious ice cream you could possibly imagine.

So, my friends, let’s get to the fun (for me) part! The CDC and various States’ Departments of Health did an incredible job identifying the bacteria and tracing it to the source before too many people got hurt. Where else can we apply STEM toward solving this ice cream problem?

One of the first things that comes to me is by developing improved monitoring systems. (Why? Because this is an area I’ve worked at in my own job, of course!) Ice cream begins its life as a liquid. Is there a way to somehow continuously filter that liquid to isolate and/or test for bacteria? Bacteria have basic genetic and chemical difference from dairy byproducts that would make them pretty easy to tell from ice cream product, assuming you could clearly identify bacteria even at very low contamination levels.

That could work for plain chocolate, vanilla, or even superman, but what about the chunky ice creams? What if you have chocolate chips, cookie dough, brownies, sprinkes, or some other goodness in the ice cream? What if there’s a contaminant in the solid chunk? How could we identify that? Would it be better to grind up all the solid parts into tiny pieces and analyze the powder that’s left, or is it better to test the ice cream in its more natural, chunky form? I don’t know! That’s a big problem to think about.

The next thing that comes to my mind is how the company cleaned their manufacturing line enough to be absolutely sure there will be no further contamination. Usually, when I work with bacteria or other biological things, the most common methods of sterilizing are bleach, UV light, or a high-pressure/high temperature cleaning using a machine called an autoclave.

In the case of making food meant for human consumption, I prefer bleach not be involved in the process – but that may be how the machines are cleaned. I imagine most of the machinery is far too big to be put into a high pressure chamber, and there may be parts within the machines where UV light won’t reach. In that case, I assume some other form of chemical cleaners are used to kill the bacteria, but I don’t know for sure. Wouldn’t it be great if we had some young STEM lady or gentleman to improve the cleaning and sterilization processes within the factory, so that safe, non-toxic, inexpensive cleaning methods can be used?

Lastly, as I think about all my friends who’ve been deprived of a summer of ice cream, I think about supply chain management – how can we quickly and efficiently get the product back out to as many consumers as possible? Which types of ice cream should phased-in first, in what order should manufacturing lines be brought back on-line, and where should the newly-made, safe ice cream be shipped first?

There are so many questions, and so many great ways we can use STEM to improve ice cream accessibility and safety. I think I’m going to grab myself an ice cream, and think about how I can get myself a job in one of the ‘coolest’ industries I can think of! Let me know how you’d use STEM to improve the ice cream industry!




Similar posts
  • STEM: Create Your Own Career Path It’s been a busy couple of weeks at my house. It’s hard to say for sure, but I think the biggest thing going on at home has been that my son started kindergarten last week (does that make me old?!?), and my daughter started at a new preschool. As such, there has been much discussion [...]
  • Am I really going to need this when I... For some of you, the first day of school has already arrived, while others are going back in the next week or two. As you get back into the routine of waking up early, going to class, and (ugh!) homework, you may be thinking about the meaning and importance of everything you’re doing. When you [...]
  • Love Travel? Try STEM! Have you guys missed me? I’ve missed you lots, but I’ve had an amazing few weeks, months even! I know it’s pretty counter to the social media dogma, but I tried to shut off my phone, and live in the moment as much as possible.  But now, I’m back, and ready to talk STEM again.  [...]
  • TBT: Viewing a Space Shuttle Launch Note: this post has been edited (changes are in italics) and may be edited again as we get more great information about space shuttle launches Friends, I took a longer absence than planned, and I apologize. Today, we’re throw-back Thursday-ing to talk about a space shuttle launch I saw in 2009.  How did that come [...]
  • Cool STEM – roller coasters! When they were kids, my husband, Mr. SciGuy and his sister had season passes to Cedar Point. They practically grew up there, and they have countless stories about riding the roller coasters, playing in the arcades, and generally making mischief throughout the park. Every year, SciGuy asks me if I want to go to Cedar [...]

Leave a Reply

Subscribe to Blog via Email

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 1,009 other subscribers