You can find more information on our web, so please take a look.
The Bentgo Stainless Insulated Food Container, for example, could hold 19 ounces and had the largest diameter of the lineup (over five inches). It only kept soup hot in our heat retention test for a little over an hour. The Hydro Flask and Miir Food Canister (four-and-a-quarter inches and four inches in diameter, respectively) suffered similar fates, although they lasted another hour. Comparatively, the Simple Modern Provision Food Jar, Thermos Stainless King Food Jar, and Zojirushi Stainless Steel Food Jar had 16-ounce capacities (except the Zojirushi, which held 12 ounces) and diameters between three-and-a-quarter and three-and-three-quarters inches. All three kept the soup above 140°F until the five-hour mark. The only thermos in our lineup that held more than 16 ounces and kept the soup hot for over three hours was the Stanley Adventure Stainless Steel All-in-One Food Jar. It had the same diameter as the Thermos Stainless King but was almost two inches taller.
Cold Retention Wasn&#;t Great
Serious Eats / Ashlee Redger
None of the thermoses kept the egg salad below 40°F for more than two hours, but it wasn&#;t necessarily because of a flaw in their insulation (although size and shape did play a part, just like in the heat retention test). To understand this, let&#;s consider the temperature ranges of food safety. When we heat soup, for example, we usually warm it to at least a simmer (around 200°F). It can cool by 60°F before it becomes a bacterial haven. Refrigerated food, on the other hand, must be held below 40°F but above 32°F lest it get icy. Even if food is nearly frozen, it only has about an 8°F window before it enters danger zone territory.
Serious Eats / Ashlee Redger
Realistically, though, most fridge-cold food is closer to 40°F than it is to 32°F, especially for items stored toward the front of the refrigerator. When we first started the cold retention test, we found that our egg salad&#;which had been chilled overnight&#;was a consistent 38°F throughout. We stashed the salad in the freezer for about 10 minutes to chill it down to 34°F before starting, although extra steps like that may not be convenient when packing lunches on busy mornings. Many manufacturers also suggested that their thermoses be pre-filled with cold water and allowed to sit for 10 minutes to help cold retention (the same thing goes for hot water and heat retention), or stored in the refrigerator overnight. Users could also add a few ice cubes to the jar, or put their food in after it has been frozen (since none of the thermoses we tested were freezer-safe themselves).
Ultimately, it is also important to consider that food doesn&#;t become immediately unsafe when it enters the danger zone. The USDA allows for one to two hours for food to sit at room temperature before it needs to be re-chilled or discarded. While using thermoses for cold food is a little trickier than for hot, they can still be used to buy some extra time.
Large, Removable Gaskets Were Easiest to Clean
Serious Eats / Ashlee Redger
Most of the thermoses were relatively easy to clean by hand. Even the ones with the narrowest openings could still fit a sponge inside, and there were no signs of staining on the metal interiors during our testing. Over time, though, the soft gaskets in the lids could become prone to staining or pick up odors or gunk. All of the insulated jars we tested had removable seals that could be washed separately, but we particularly liked the Hydro Flask&#;s red silicone one, which was broad enough that it could be put into the dishwasher apart from the lid without us fearing it would get lost or destroyed (a missing or misshapen gasket can lead to leaking and reduced insulation power). If the thermos had an exposed pressure release gasket, we also evaluated those. Most were easy to remove and replace except for Bentgo&#;s, which we struggled with for several minutes before we got it back in.
The Criteria: What to Look for in a Food Thermos
Serious Eats / Ashlee Redger / Grace Kelly
A great thermos should be easy to use, convenient to carry, and maintain heat for several hours. Look for an insulated jar that matches up with your usual portion size (we liked 16-ounce models, which performed well with 10 ounces of soup but also allowed enough space for multi-component meals). For the best temperature retention, look for a thermos that is tall and narrow versus short and wide. A textured or handled lid can help make it easier to open, especially when pressure builds up inside from hot contents (although we did not experience any stuck-on lids during our testing). The lid should be leakproof and have a thick, easily removable gasket for cleaning. We gave thermoses bonus points for being partially or fully dishwasher-safe, but most models recommend handwashing anyway to maintain the look and performance of the thermos over its lifetime.
Our Favorite Food Thermoses
What we liked: The Simple Modern Provision Food Jar was a no-frills model that stood out because of its reliable temperature retention. It kept our portion of chicken noodle soup hot for five hours and the egg salad cold for almost two. Its handled lid made it convenient to carry and easy to open. The gasket inside the cap was quick to remove and replace when needed for cleaning, plus the whole thermos could be washed on the top rack of the dishwasher (although handwashing is recommended). Its durability was the cherry on top of this impressive model: it got a few scratches and the paint chipped a little after being dropped repeatedly on the sidewalk, but no major dents.
What we didn&#;t like: This model was the top performer in heat retention the last time we evaluated food thermoses, but it failed the leak test. A few online customer reviews also mention leaking, which could be caused by a faulty or misaligned gasket. We didn&#;t experience any unexpected drips this time (even when we retested it after dropping it on concrete), but it may be something to watch for.
Key Specs
Serious Eats / Ashlee Redger
What we liked: Thermos originally set the standard for insulated food and beverage containers, so much so that its name became the generic term for the whole category. This model proved the brand&#;s enduring quality by matching our overall winner&#;s temperature retention in both tests; it kept soup hot for five hours and egg salad cold for almost two. We liked its folding steel spoon (which felt nice and sturdy, especially compared to the Thermos FUNtainer&#;s bendy plastic one).
What we didn&#;t like: This model had a relatively narrow mouth opening that made filling difficult, especially when ladling in soup. The specific jar we tested came with a small dent in its side, and it got several more dings (plus some scratches in the paint) when dropped during the durability test.
Key Specs
Serious Eats / Ashlee Redger
What we liked: This Stanley was our overall top pick in our previous round of testing, and we loved it again this time. It had the most extra perks of any model, namely a sizeable lid cover (which doubled as a bowl), an attachable spork, and a separate container in the stopper to store things like oyster crackers, tortilla chips, or a small snack. It kept our 10 ounces of soup hot for almost four hours (impressive, considering it was only about half-full) and kept the egg salad cold for nearly two. While it didn&#;t retain heat quite as well as our other two with the portions we used, we&#;d recommend it to people who have bigger appetites or usually pack multi-component meals (like rice, chicken, and vegetables) since it will maintain temperatures even better when it is fuller.
What we didn&#;t like: It was convenient that the spork attached to the side of the thermos, but its surface was left exposed there, which didn&#;t feel super hygienic. The jar and lid also dented and scratched more than our other winners during the durability test, perhaps because it was the heaviest model of the lineup. The insulated body was not dishwasher-safe, although the rest of the parts were.
Key Specs
Serious Eats / Ashlee Redger
For more information, please visit SANNE.
The Competition
FAQs
What temperatures should food stay between to be safe?
The range between 40°F and 140°F is often called the &#;temperature danger zone&#; because it is the span in which bacteria can quickly multiply and spread throughout food. For that reason, cold food should be kept at 39°F or below, and hot food should stay above 140°F. If it needs to be chilled, it should be done quickly to minimize the time the food spends in the danger zone. The USDA recommends discarding any food that has been within this zone for two hours or more (or after one hour if the temperature is 90°F or above).
How long can a food thermos keep food warm?
How long a food thermos can keep its contents warm depends on its shape, how hot the food is going in, how full the thermos is, and the ambient temperature surrounding it. Our favorite models kept a 10-ounce portion of soup above 140°F for about five hours. To get the best heat retention from your insulated food jar, most manufacturers suggest filling it with boiling water to let it preheat, then dumping out the water and filling it with hot food. The same can be done with ice water for cold food. We recommend using a thermos about the same size as your usual portion, as partially empty containers don&#;t maintain heat as well as full ones.
Can you use a food thermos to keep foods cold?
Yes, to an extent. While properly insulated jars can keep their contents warm or cool, fridge-cold food is usually between 33°F and 39°F. It only has a few degrees (if that) of leeway before it enters the temperature danger zone. None of the models we tested could keep egg salad from the refrigerator under 40°F for more than two hours. The best way to compensate for this is to make the food colder to start with by adding in a couple of ice cubes or freezing the food (either for a few minutes to cool it by a couple of degrees or overnight if the food will need to stay chilled for several hours). Add the food to the thermos after it comes out of the freezer, as most insulated jars aren&#;t safe to go into the freezer themselves.
Can you use a drink thermos to keep food warm or cold?
Yes, drink thermoses often use the same kind of double-walled vacuum insulation as food thermoses and can be used to keep their contents hot or cold for a few hours. Because drink containers tend to have narrower openings, though, they may be slightly more challenging to fill and eat out of than wide-mouthed food jars.
What's the best food thermos for camping?
The best food thermos for camping is the one that can keep food hot, and out of the temperature danger zone, the longest. In our tests, we found the Simple Modern food jar kept foods hot for five hours and cold foods chilled for two. This was quite good compared to other models, and we think it would do well on a short camping trip. Keep in mind that conditions can vary, and if you're keeping a hot thermos of food in your backpack on a colder day, it might chill faster. Best be safe and toss food that's been between 40°F and 140°F for two hours or longer.
Why We're the Experts
In today's fast-paced world, the importance of a well-preserved and fresh-packed lunch cannot be overstated. Insulated lunch bags have become indispensable for individuals seeking to maintain the temperature of their meals, whether it's a homemade sandwich, salad, or hot soup. Have you ever wondered how these bags work their magic to keep your food at the desired temperature? In this comprehensive exploration, we will delve into the science behind how insulated lunch bags work, unraveling the mechanisms that enable them to effectively insulate and protect your meals.
Let&#;s delve deeper in how do insulated lunch boxes work:
At the core of insulated lunch bags is the principle of thermal insulation. These bags are designed with layers of specialized materials that possess excellent thermal insulating properties. Commonly used materials include foam, foil, and other insulating fabrics. The primary objective is to create a barrier that minimizes the transfer of heat between the inside and outside of the bag.
The insulating materials work by reducing the conduction, convection, and radiation of heat. Conduction involves the direct transfer of heat through solids, while convection is the heat transfer through liquids or gases. Radiation, on the other hand, is the transfer of heat through electromagnetic waves. By incorporating materials that resist these heat transfer methods, insulated lunch bags effectively maintain the desired temperature inside, whether it's keeping your cold drinks cool or your hot soup warm.
Many insulated lunch bags utilize reflective foil technology to enhance their insulating capabilities. The interior lining of these bags often features a layer of reflective foil, which serves to bounce back radiant heat. This prevents external heat from infiltrating the bag and helps to maintain the internal temperature.
The reflective foil technology is particularly effective in preserving the freshness of hot or cold items for extended periods. It acts as a shield against external temperature fluctuations, ensuring that your food stays at the desired temperature until it's time to enjoy your meal.
In addition to thermal insulation, the effectiveness of insulated lunch bags also lies in their ability to create a sealed environment. A well-designed insulated bag minimizes the exchange of air between the inside and outside, preventing the escape of cold or hot air. This airtight seal not only helps in temperature retention but also plays a crucial role in preserving the flavors and freshness of your food.
Some insulated bags come with specially designed zippers or closures that ensure a tight seal. The combination of thermal insulation and airtight sealing makes these bags a reliable choice for keeping your lunch as fresh as possible.
The choice between a zipper or Velcro closure is not merely a matter of personal preference; it significantly contributes to the bag's overall performance. A secure closure system is paramount in preventing heat exchange and maintaining the integrity of the insulated environment. This section explores the nuances of each closure type, highlighting their respective advantages and considerations for different use cases.
Taking the insulation game a step further, some insulated lunch bags come equipped with designated pockets or compartments for cold packs or heat packs. These additional elements play a pivotal role in extending the duration for which your meals stay at the desired temperature. Unpacking the practicality of integrating cold or heat packs into your lunch bag routine provides valuable insights into optimizing its performance.
For those seeking top-tier insulation, double-layer construction is a feature worth considering. This advanced design involves incorporating insulating material between the layers of the bag, creating an additional barrier against temperature fluctuations. Exploring the intricacies of this construction sheds light on how it elevates the performance of insulated lunch bags, making them suitable for a range of culinary preferences and dietary needs.
Beyond the thermal considerations, the longevity of an insulated lunch bag depends on its maintenance. Choosing materials that are not only effective but also easy to clean is a crucial aspect of ensuring the bag's durability. This section explores the significance of proper cleaning routines, emphasizing the correlation between cleanliness and sustained thermal performance.
Selecting the right insulated lunch box is crucial for ensuring your meals stay fresh and at the desired temperature throughout the day. Here are some essential tips to guide you in choosing the perfect insulated lunch box:
When choosing an insulated lunch box, consider the amount of food you typically bring with you. Ensure the lunch box has enough capacity to accommodate your meals and snacks without being excessively bulky. A well-proportioned size ensures convenience without compromising on storage space.
Pay attention to the insulation material used in the lunch box. Common materials include foam and thermal fabrics. Opt for high-quality insulation that effectively retains heat or cold, depending on your intended use. Closed-cell foam is known for its excellent insulating properties.
The effectiveness of insulation relies on a secure closure mechanism. Look for lunch boxes with reliable zippers, Velcro, or snap closures. A tight seal prevents heat exchange with the external environment, maintaining the internal temperature for a more extended period.
The duration for which insulated lunch bags keep food warm varies based on factors such as the bag's insulation quality, the initial temperature of the food, and external conditions. Generally, a well-insulated lunch bag can keep food warm for 2 to 4 hours. To maximize warmth retention, preheat the bag, use insulated containers, and consider adding heat packs. Testing your specific lunch bag with your typical meals will help determine its individual performance.
Opt for a lunch box that is easy to clean to maintain hygiene. Look for materials that resist stains and odors, and check if the lunch box is machine washable or has removable liners. Easy cleaning contributes to the overall lifespan of the lunch box.
Consider the portability of the lunch box, especially if you need to carry it daily. Look for features such as padded handles, shoulder strap lunch bags, or even backpack-style designs for added convenience. A well-designed lunch box enhances both functionality and aesthetics.
Ensure that the lunch box is compatible with your preferred food containers. Some lunch boxes come with designated compartments or pockets for specific container sizes. Compatibility ensures efficient use of space and helps prevent spills during transportation.
Choose a lunch box with extra pockets or compartments for storing utensils, napkins, or condiments. These additional features contribute to the overall convenience and organization of your lunch box.
In conclusion, the science behind how insulated lunch bags work is a fascinating blend of thermal insulation, reflective foil technology, and effective sealing mechanisms. These bags have evolved to become essential tools for those who prioritize enjoying a fresh and well-preserved meal. Whether you're packing a cold lunch for a summer picnic or keeping your hot soup warm during a winter commute, understanding the workings of insulated lunch bags can help you make informed choices and fully appreciate the convenience they bring to our daily lives.
Shop for the best quality lunch bags and rolling backpack for kids from J World Sports and get the best products at affordable prices.
For more Lunch bags with thermal insulation Manufacturerinformation, please contact us. We will provide professional answers.