154 | 100% Preventable Listeria Deaths | Freezer Temp Trends | Space Beer |
Plus, a guilty plea for almost two decades of fish fraud
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Food safety trend: Freezer temperatures to increase?
Sanitation failures and death toll increases in Listeria deli-meat outbreak;
Food Safety News and Resources;
Space beer = good beer;
Food fraud news, and recent incidents.
Question: Who keeps doing fish fraud after food safety officers have executed a search warrant to investigate your dodgy practices? Answer: Two managers from the largest fish wholesaler on the Mississippi Gulf Coast, that’s who! They pleaded guilty to crimes including conspiring to commit wire fraud and misbranding last week. The company they worked for admitted to selling frozen imported fish from Asia, Africa and India as fresh and locally-caught. For seventeen years. Wow.
Hi, welcome to issue 154 of The Rotten Apple. And a huge shoutout to Sky from the UK for upgrading to a paid subscription. I rely on the support of readers like Sky to produce this newsletter each week. Thank you.
In this week’s issue I explore the emerging debate around frozen food temperatures and share some shocking news about what was going on in the factory that made the deli-meats at the centre of a deadly Listeria outbreak in the USA.
Plus some good news about fermentation for space travellers.
Have a wonderful week,
Karen
P.S. If you love this newsletter, please tell your friends and colleagues about it and help grow our community of global food safety champions.
Food Safety Trend: Freezer Temperatures to Increase?
Is minus 18 too cold? The debate heats up
We love to cool things down: our homes, offices and buildings, pharmaceutical products, data centres, and food. We are now cooling more things more often as our planet warms, and as emerging middle classes in China and India buy more refrigerated foods and use more air conditioning in their homes and offices.
Refrigeration and air conditioning are responsible for 10% of greenhouse gas emissions globally, three times higher than aviation and shipping combined. Three quarters of these emissions come from energy consumption, while the other quarter is from leaks of refrigerant gasses. The emissions from cooling are growing three times faster than other emissions, making cooling services an important battleground in our fight against global warming.
When we reduce energy consumption in food supply chains we can make a meaningful impact on greenhouse gas emissions.
The challenge with reducing energy consumption in refrigeration and freezing is that effective cold chains are vital for preventing food waste and for ensuring food safety. How to reduce the amount of energy needed without risking losses from food spoilage, and illnesses?
Warmer ice cream to the rescue!
In November, Unilever announced plans to raise the temperatures of its ice cream cabinets, which contribute a significant portion of the multinational’s greenhouse gas emissions.
Unilever, which owns food brands including Walls (Streets in Australia), Magnum, Ben & Jerry’s and Hellmann's, owns close to three million ice cream cabinets, which it leases to retailers worldwide. When run at the industry standard set-point of -18°C (0°F), these cabinets contribute approximately 10% of Unilever’s greenhouse gas emissions. Altogether, the ice cream category creates 20% of Unilever’s emissions.
The multinational announced its plans to increase the operating temperature of its ice cream display cabinets from -18°C (0°F) to -12°C (10°F) in November 2023. Pilot operations in Germany had already shown the move could result in energy savings of 25%.
Around the same time, Unilever announced it was reformulating its ice cream products to withstand warmer storage temperatures. In a highly unusual move for the famously competitive and secretive food industry, Unilever said it would share its reformulation technologies with its competitors in the ice cream category, announcing it would grant free, non-exclusive licences to 12 patents for ice cream reformulation technologies.
“By granting a free non-exclusive licence to these 12 reformulation patents, we hope our peers and partners from across the ice cream sector will benefit and work to tackle emissions across the industry,” said Andy Sztehlo, chief R&D officer for ice cream at Unilever.
Reformulating ice cream is no easy task. Ice creams sold in single-serve wrappers need to remain firm enough to retain their shape during handling and storage. They should melt slowly when removed from the freezer, but quickly in the mouth to provide an enjoyable mouth feel. This melting profile is influenced by both ice content and ice crystal size, two important quality attributes which are significantly affected by freezer temperatures.
Successful ice cream re-formulations deliver the correct ice characteristics at warmer temperatures while still providing the same eating experience for consumers as the original product.
Beyond ice cream
The UK supermarket chain Morrisons has joined Unilever in the fight against emissions from freezers. Last month it increased the temperature of its freezers in ten of its stores, as part of its commitment to achieve net zero carbon emissions by 2035.
The Morrison freezers now operate at -15°C (0°F), up from -18°C. A spokesperson for Morrisons said they could ensure the quality and safety of their food at the higher temperature because modern freezers and monitoring technologies provide comprehensive information about frozen food temperatures – information that was not available when -18°C convention was chosen as the standard set-point for frozen food.
This is part of a wider push by a group called The Move to -15 o C Coalition to encourage the global frozen foods industry to change the current industry-accepted frozen foods standard from -18°C to -15°C. The group is a coalition of companies that aims to make frozen food logistics more sustainable and efficient.
A global move to -15°C would save 17.7 million metric tons of carbon dioxide per year, the equivalent annual emissions of 3.8 million cars. The move would also save 25 terawatt hours of energy per year and cut food supply chain costs by 5% to 7%, says the group.
It’s worth noting that The Move to -15°C is funded by DP World, a multinational logistics company with more than 100,000 employees which is owned by the government of Dubai via a holding company. The company operates maritime ports and inland terminals in over 40 countries, and provides cargo logistics and maritime services internationally, accounting for about 10% of global container traffic. DP World would reap significant financial benefits from reduced energy costs if there was a global change to temperatures for the transport of frozen foods.
What about food safety?
The current standard international temperature for transporting and storing frozen food is -18°C, a figure that was set 94 years ago and hasn’t changed since. Being significantly colder than the freezing point of most foods, it provides a large margin to prevent foods from suffering quality and safety issues if they are subject to warmer temperatures for short periods.
In other words, frozen food at -18°C takes longer to warm up to temperatures that would negatively affect its quality or safety compared to food stored at a temperature close to its freezing point.
Despite this large margin of safety, the standard set-point is sometimes exceeded by individual companies that set their freezers even colder, due to risk-averse corporate policies, or to position themselves as industry leaders.
A team of scientists from the International Institute of Refrigeration, the University of Birmingham and London South Bank University, explored whether the safety and quality of frozen food would be compromised by increasing the set-point by 3 degrees Celsius.
They concluded that a set point of -15°C would not impact food safety. As for quality, they were more circumspect, saying “how food is treated and managed prior to freezing has just as much, if not more, impact than what happens during the frozen storage stage”.
Icecream is perhaps the product most at-risk from a move to -15°C due to the quality impacts of ice crystal size. Consumers can detect large ice crystals, which are favoured at warmer storage temperatures, and these crystals are associated with poor quality in ice cream.
For other food categories, a study conducted by Nomad Foods, owners of Birds Eye, Findus and Iglo brands (UK), with the assistance of Campden BRI, provides insights.
In their study, Nomads Foods considered the quality implications on frozen foods, including poultry, breaded fish, unbreaded fish, plant-based foods and pizza, during storage at -15°C and a range of warmer temperatures, up to -9°C.
They found there was no noticeable impact on product safety, texture, taste or nutrition for products stored at -15°C. However, they did find some impacts on sensory attributes and vitamin C content for salmon fillets and vegetable products at temperatures of -12°C and -9°C.
Additionally, they noted energy savings of 10% to 11% (Source: Nomad Foods (2023), extra data via Institute of Refrigeration, Centre for Sustainable Cooling (2023))
Challenges of switching to -15°C
While energy savings, cost savings and greenhouse gas emissions reductions are all significant benefits of a switch to -15°C, there remain some challenges.
If frozen food remains frozen, and does not thaw or partially thaw, it is generally considered to remain safe, regardless of the temperature. However, risks to safety and quality arise during inevitable breaks in the cold chain when frozen food moves between temperature-controlled environments. For example, when it is moved from warehouse to transport container; from container to receiving warehouse; from cold storage to retail display cases and from the store to consumers’ homes.
Equipment failures, malfunctioning thermostats, poorly managed defrost cycles and power outages also pose risks to the quality and safety of frozen food, with foods that are stored at -18°C less likely to reach ‘dangerous’ temperatures during a failure event compared to foods stored at -15°C.
Morrisons and The Move to -15oC both suggest that modern monitoring technologies, efficient equipment and optimised freezer protocols are required to mitigate the risks from breaks in the cold chain. Such technology is less accessible to operators in developing countries, increasing the risks in those countries.
Different legal requirements in different countries could result in a ‘patchwork’ of temperatures through a supply chain, with companies that choose to operate at -18°C being disadvantaged by the cost of cooling incoming goods they receive from suppliers operating at -15°C.
Food safety CCPs (critical control points) that rely on freezing for pathogen inactivation have not been considered by the groups promoting a switch to -15°C, as far as I can tell. For example, anisakid nematodes (parasites) are hazards in marine fish eaten undercooked or raw, for example in sushi. Freezing is used as a control method for such parasites. Would a warmer freezer be less effective as a control method? Perhaps. This requires investigation.
What happens next?
Just four months after announcing plans to increase its ice cream cabinet temperatures and share its reformulation patents, Unilever announced it would leave the ice cream category altogether. In March 2024, the multinational announced its ice cream brands would be moved to a standalone entity, perhaps with the intention to sell them.
Unilever’s ice cream business has different storage, equipment and transport requirements than the remainder of their business, which utilises ambient supply chains, so divesting it will simplify operations and reduce costs.
Meanwhile, other businesses are no doubt following Nomad Foods’ lead and quietly investigating whether warmer freezers can deliver the same quality for their products while saving emissions and money.
In short 🍏 Some food companies and logistics providers are considering a switch from -18°C (0°F) to -15°C (5°F) for frozen food storage and transport 🍏 Food safety is not affected at -15°C but food quality can be impacted, particularly for foods like ice cream 🍏 An increase in temperature increases the likelihood of safety and quality failures when the cold chain is interrupted 🍏 Significant savings on energy, and significant greenhouse gas emissions reductions can be achieved when freezers are operated at warmer temperatures 🍏
Further reading
Read a lively debate and discussion by food industry professionals, including ideas about why -18°C was chosen, on LinkedIn
Green Cold and the Global Goals | Birmingham Energy Institute
Key implications on food storage in cold chain by energy management perspectives (frontiersin.org)
Three Degrees of Change – Frozen Food in a Resilient and Sustainable Food System (movetominus15.com)
Listeria in deli meats: death toll rises
At least seven million pounds of products have been recalled and the death toll has almost doubled since I reported on a Listeria outbreak linked to Boar’s Head brand deli meats in the USA last month. Nine people have died and 57 have been hospitalised - a mortality rate of sixteen percent.
Shockingly, a report by the US Department of Agriculture (USDA), obtained under a freedom of information request by CBS News, showed that the USDA’s inspection service (FSIS) had noted 69 sanitation failures at the facility where the meats were made in the 12 months preceding the outbreak.
Food safety failures at the site included clogged drains, condensation issues, meat buildup in pumps that emitted a strong odour, large patches of “mold-like substance” up to several feet wide in a cooler, buildup of meat protein on walls, overflowing drains and meat residue from past production batches on food contact surfaces.
Takeaways
This facility was producing ready-to-eat deli meats, a product known to be high-risk for Listeria. Manufacturers of high-risk foods must practice good sanitation, good food handling practices and appropriate monitoring protocols. If they fail to do so, they risk killing people with their products.
The sanitation failures at Boar’s Head documented by USDA inspectors seem a likely cause of the recent outbreak and deaths, outcomes that were one hundred percent preventable. Shame on you, Boar’s Head.
Sources: https://www.cbsnews.com/news/bugs-mold-mildew-inspection-boars-head-plant-listeria/ and https://www.foodsafetynews.com/2024/08/inspection-report-reveals-history-of-sanitation-issues-at-boars-head-plant-linked-to-deadly-listeria-outbreak/
🍏 Learn: A Guide to Listeria Controls and Environmental Monitoring Programs (supplement for paying subscribers) 🍏
Food Safety News and Resources
My food safety news and resources posts have no fluff, no filler, no ads, no promos, no junk, just expertly hand-curated food safety news from around the globe, brought to you each week
This week’s news has some good resources if you are interested in allergens or food waste. Click the preview below to read.
Space Beer = Good Beer (Just for Fun)
My partner is a space nerd. Last night he told me he wants his final journey to be to Jupiter. Right!
A journey to Jupiter would take years and no doubt he’ll want the occasional cold beverage during his trip. Fortunately, food microbiologists have already begun to explore how fermentation works in space.
They theorised that yeasts used to make beer would behave in unexpected ways when subject to microgravity conditions, and this could make it impossible to produce beer in space (sad news).
However, in a surprising (and welcome) twist, when researchers created a homebrew with Saccharomyces pastorianus, the yeast used for brewing lager, under microgravity conditions, they discovered the fermentation was more efficient. The low gravity conditions also encouraged the yeast to express a gene related to ester production differently compared to earth gravity conditions, leading to higher quality beer.
So space beer = good beer! Great news for my fella.
The paper:
Pedro Fernandez Mendoza, Thompson-Witrick, K.A., Moreno, S.R., Cárdenas-Pinto, S., Jia, Z., Zotarelli, L., Zhang, B. and MacIntosh, A.J. (2024). Brewing Beer in Microgravity: The Effect on Rate, Yeast, and Volatile Compounds. Beverages, [online] 10(2), pp.47–47. doi: https://doi.org/10.3390/beverages10020047.
Below for paying subscribers: Food fraud news and incident reports
📌 Food Fraud News 📌
In this week’s food fraud news:
📌 Cooking oil scandal repercussions;
📌 Seafood, soy sauce, paprika, GMO, geographical origins, edible oils methods;
📌 Prawns, fake milk, dried apricots;
📌 A guilty plea for a 17 year fish fraud in the USA.
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