Are mason jars safe to use for hot soups?
Based on 1 peer-reviewed studykitchen
Verdict: Safer
Yes, if the jar is at room temperature before pouring. They can crack from cold-to-hot shock.
What's actually in it
Mason jars are soda-lime glass. They're not as thermal-shock-resistant as borosilicate but handle hot food fine if at room temperature first. Cold-out-of-the-fridge + boiling soup = crack.
What the research says
Glass itself is inert. A warm-up step prevents physical breakage. A 2025 study on hot liquids in plastic containers shows why glass is the cleaner swap.
For take-to-work soup, preheat the jar with hot tap water for a minute, then pour in the hot soup. Close with a two-piece metal lid or silicone-sealed cap.
The research at a glance
| Study | Journal | Year |
|---|---|---|
| Release of Nanoplastics from Polypropylene Food Containers. | J Agric Food Chem | 2025 |
What to use instead
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