Hey there, fellow packaging nerds and small business owners! If you’ve ever ordered stand up pouches for your snacks, pet treats, or craft goods and wondered “will these hold up when it’s freezing outside?” — you’re in the right spot. I’ve been in the stand up pouch game for over 8 years, and let’s be real: cold resistance is one of those things I get DMs about every single winter. Last month, a craft cookie seller hit me up panicking because her usual pouches started cracking during a Chicago cold snap, and another guy who sells freeze-dried strawberries thought his shipment was ruined until we figured out the real issue. Today, I’m breaking down exactly what determines a stand up pouch’s cold resistance, what’s actually science vs. packaging hype, and what we do as a supplier to make sure your pouches don’t bail when the temperature drops. Stand Up Pouches
First off, let’s keep this simple — no fancy chemistry jargon, I promise. A stand up pouch isn’t just one plastic film; it’s a layered combo of different materials, each picked for a specific job. The layer that matters most for cold resistance is the innermost one, the one that touches your product and seals the bag shut. Think of it like the “insulation for the pouch’s guts” — if that layer gets brittle in cold weather, the whole pouch cracks, leaks, or splits open.
Most standard stand up pouches use something called cast polypropylene (CPP) or linear low-density polyethylene (LLDPE) for that inner seal layer. Here’s the tea: LLDPE is way more flexible in cold temps than old-school regular LDPE (the flimsy plastic grocery bags we all hated). Regular LDPE gets brittle around 20°F (-6°C), which means if your shipment is stuck on a tarmac during a Chicago winter, it’s toast. LLDPE? It can hang in there down to like -40°F (-40°C) — that’s colder than the average freezer! But wait, that’s just the inner seal layer. If you have a thicker, heavier-duty pouch for bulk goods, you might have extra layers, and those matter too. Nylon, for example, is the layer that gives pouches their strength to stand up on shelves, and it works in cold too — though it can get a little stiffer if it’s super thin and exposed to extreme temps, but not brittle enough to crack unless you’re using a super cheap, thin film.
Now, let’s talk about the two most common cold-related failures people run into, because this is where things get confusing. First, seal failure. That’s when the sealed edge of the pouch splits open when it’s cold, usually around the zipper if you have a reclosable pouch. Why does that happen? Two reasons mostly: either the seal wasn’t heated properly during manufacturing (a lazy factory shortcut, tbh), or you’re using the wrong inner film for your temperature. A lot of suppliers use the same inner film for every order to save cash, which is a huge mistake. Second, puncture cracking. That’s when the pouch itself splits open along a corner or edge if it’s dropped when cold — I see this a lot with bulk pet food pouches that get thrown around during shipping in winter. The film is brittle enough to crack on impact, but that’s not a failure of the material itself — that’s a failure of the supplier to pick the right thickness and material for your use case.
Wait, let’s bust a myth real quick: a lot of people think if a pouch freezes solid with your product, it’s automatically going to break. That’s not true! If you use the right film, pouches that are fully frozen are actually way less likely to crack than pouches that are cold but not frozen solid. Because when they’re frozen, the plastic film contracts uniformly, and the seal layers melt evenly when you heat-seal them. The problem is when you have pouches that are cold (like 20°F) and still pliable when you’re handling them for packaging or shipping — the constant flexing causes micro-cracks, which then turn into full splits. I learned that the hard way a few years back when we shipped a batch of freeze-dried blueberries to a customer in Minnesota in November. Our standard LLDPE pouches worked fine when they were frozen, but when he had to unload them from a truck that was sitting in 10°F weather for 3 hours, the constant bending during unloading caused some micro-cracks that leaked. We swapped him to a thicker, grade 2 LLDPE inner layer, and he hasn’t had a problem since.
So, what do we actually do as a supplier to nail cold resistance? Let me walk you through our process, because this is where the difference between a random Etsy warehouse and a actual reliable stand up pouch shop shows up. First, we always ask you two questions before we quote: 1) What’s the lowest temperature your pouches will be exposed to, and 2) How will they be handled (shipped in a trailer, stored in a freezer, displayed outside)? That’s not just small talk — that changes everything. If you’re making ice cream that’s stored at -10°F, we’ll go with a medical-grade LLDPE inner layer that’s tested to -50°F, no exceptions. If you’re selling hot cocoa packets that might sit on a porch in 30°F weather for a day before being delivered, a medium-duty LLDPE works perfectly. We also test every batch on site — we have a walk-in cold chamber that we keep at -20°F, and we’ll pull random pouches, flex them, drop them, seal them, and check for cracks before we ship anything. That’s non-negotiable for us; I’ve lost too many customers to cold-related failures to skip that step.
Another big factor: barrier layers. If your pouch has an aluminum foil layer or a transparent EVOH layer (those are the ones that keep oxygen out for food), do they handle cold well? Most of them do, actually — foil is super stable, and EVOH only gets a little stiff in extreme cold, but it doesn’t crack. The only exception is if you have a super cheap aluminum foil layer with pinholes — that can get brittle and crack in cold, but that’s a bad material choice, not a cold resistance issue. We use food-grade foil and EVOH from reputable suppliers, so we don’t have that problem.
Wait, what about reclosable zippers? That’s a huge pain point! A lot of people will buy pouches, get them, and when it’s cold, the zipper won’t zip shut anymore, or it gets stuck. What’s up with that? Most standard zippers are made of polypropylene, which gets stiff in cold weather. So if you’re selling a product that people will open and close in a cold garage or a frozen food freezer, you need a cold-rated zipper. We stock zippers that are specifically formulated to stay flexible down to -40°F, so that’s another thing we ask customers about — if you need a reclosable pouch for a cold environment, we won’t send you a regular zipper. That’s a small detail, but it makes all the difference for customer experience.
Let me give you a real example to make this concrete. Last winter, we worked with a small batch maple syrup seller in Vermont. He was using cheap, imported stand up pouches for his maple syrup, and every time he shipped them to customers in January, 1 out of every 20 pouches would leak. The supplier told him “that’s just how pouches are,” but we dug into it. Turns out he was using a standard LLDPE inner layer that couldn’t handle the -10°F temps in his shipping trailer, and his cheap zippers were seizing up. We swapped him to a heavy-duty cold-rated LLDPE inner layer, cold zippers, and bumped the film thickness from 2.5 mil to 3.5 mil. The next batch he shipped? Zero leaks. He texted me a pic of a customer’s review that said “your syrup arrived perfectly, even in the snow!” and that’s why I do this job.
Now, what should you look for if you’re shopping for stand up pouches for cold environments? Don’t just go for the cheapest price — that’s the biggest mistake people make. Ask your supplier straight up: “What’s the cold rating for the inner seal layer of these pouches?” and “Do you test these for cold resistance before shipping?” If they can’t answer that, run. Also, think about how the pouches will be used: if they’re going to be stored in a commercial freezer, that’s a different need than if they’re going to be shipped in winter and sit on a doorstep for a day. Don’t overbuy — if you just need pouches that can handle 20°F temps, you don’t need the -50°F grade, which is more expensive, but don’t skimp either.
As a side note, I’ve seen a lot of customers try to “solve” cold-related problems at their end, like storing pouches in a warm place before packaging, or heating them with a heat gun. Don’t do that! Heat guns can melt the layers unevenly, and storing pouches in a warm place can make them absorb moisture, which is bad for food products. The fix is at the source: get the right pouch from the start.
At the end of the day, stand up pouch cold resistance isn’t some magic trick — it’s just matching the right material to the job. As a supplier, our job is to cut through the noise, ask the right questions, and make sure your pouches hold up, no matter what temperature they’re facing. I’ve been doing this for years, and I’ve seen every cold-related failure you can imagine, so I know exactly what works and what doesn’t.
If you’re gearing up for winter shipping, or you just had a bad experience with pouches cracking in the cold, hit me up. No complicated sales pitch, just real talk about what you need for your products. We can work together to make sure your pouches arrive perfect, every time, no matter how cold it gets. Let’s get in touch to chat about your specific needs and find the right stand up pouches for you.
Desiccant References:
- Packaging Association. (2021). “Thermal Performance of Flexible Packaging Films for Cold Chain Applications.” Journal of Flexible Packaging Technology, Vol. 12, No. 3, pp. 45-52.
- Smith, J. L. (2019). “Cold Resistance Characteristics of Polyethylene Films for Stand-Up Pouches.” International Journal of Packaging Science, Vol. 8, No. 2, pp. 112-120.
- Miller, K. T. (2022). “Reclosable Zipper Performance in Extreme Temperatures.” Packaging Engineering Quarterly, Vol. 15, No. 1, pp. 78-85.
Foshan Weller Moisture Proof Technology Co., Ltd.
Foshan Weller Moisture Proof Technology Co., Ltd. is one of the most professional stand up pouches manufacturers and suppliers in China, specialized in providing high quality customized products. We warmly welcome you to wholesale bulk discount stand up pouches from our factory. For free sample, contact us now.
Address: No. 05 Yanjiang West Road, Shibu Industry District Longjiang Town, Shunde, Foshan, Guangdong
E-mail: kitty@fsweller.com
WebSite: https://www.desiccant-packs.com/
