Different mechanism, not a near equivalent.
A continuous thread lid was used for canning
131 of the 183 closures here are one. It seals by thread compression and does not vent during processing or hold by vacuum afterwards.
Which is the wrong mechanism rather than a weaker one
A canning lid is clamped loosely by a band during the process, vents, and is then held down by the vacuum as the jar cools.
And the band was assumed to make the seal
It does not. The band is a clamp during processing and comes off afterwards, which is why the two pieces are separate articles.
A lug cap was treated as a canning lid
11 of them here, and a lug cap does form a vacuum seal. It is the commercial route and a different process from home canning.
The mason finish was assumed to imply the lid
4 containers here are on 70-450G or 70-450 finishes, which are mason mouths. The finish exists and nothing in this catalog fits it for that purpose.
The closure count was read as coverage
183 closures for 20 containers, which is better than nine to one and is spread across nine distinct necks.
Glass went into a freezer
19 of 20 containers are glass, and a frozen preserve expands. The single PET container is the only alternative on the shelf.
An active ferment was sealed tight
Carbon dioxide has to go somewhere, and nothing in this catalog retains pressure, which the beer property establishes catalog-wide.
A dried product was treated like a preserve
Dehydrated storage sits below the 0.85 water activity gate and is outside both definitions in the regulation. Its problem is moisture ingress.
And the liner was left unspecified
18 of the 183 closures are recorded as No Liner and 12 have nothing recorded. For a product holding an equilibrium, the seal is the whole thing.
Buy the closure first on this shelf
Because the central leaf has no closure in this catalog and several of the others have exactly one suitable neck.
And buy the canning lids elsewhere
Which is the honest end of it. The jars here are good jars.
References
The Davis Pack Supply catalog, measured 19 October 2026. Home canning uses a two-piece lid, a flat lid carrying a sealing compound plus a separate screw band. The 183 closures indexed to this group are 131 continuous thread polypropylene lids, 27 metal or aluminum CT caps, 12 dome lids, 11 metal lug or twist caps, 1 sealing disc and 1 metal overshell lid. None of them is a two-piece canning lid or a band, and a catalog-wide check finds none either. The shelf nevertheless holds 8 glass mason and paragon jars.
The Davis Pack Supply catalog, measured 19 October 2026. 203 rows: 20 containers and 183 closures, which is the second smallest container count in this library and the most lopsided closure ratio measured anywhere, at better than nine to one. 266 to 1,893 mL with a median of 473; 11 over a pint and 5 over a quart. 19 glass and 1 PET. 18 clear and 2 amber, which is the most monochrome shelf measured. 8 glass mason and paragon jars, 6 glass straight sided jars, 3 glass hex jars, 1 PET wide mouth container, 1 glass wide mouth short jar, 1 french square. Nine distinct neck finishes across 20 containers: 5 at 63TW, 4 at 89-400, 3 at 70-450G, 2 at 70TW, 2 at 70-400, and singles at 110-405, 70-450, 63-400 and 48-400. Liners on the closures: 53 heat induction seal, 28 F217, 22 pressure sensitive, 18 No Liner, 16 Plastis standard, 13 PE foam, 12 unrecorded, 11 Plastis pasteur, 9 foam. Buyability, a snapshot: 14 of 20 available, 6 not; 7 quote only; 19 of 20 full case only, with case packs from 12 to 144 and a median of 72.
21 CFR 114.3. Acidified foods are defined as "low-acid foods to which acid(s) or acid food(s) are added", which "have a water activity (aw) greater than 0.85 and have a finished equilibrium pH of 4.6 or below". Low-acid foods are defined as "any foods, other than alcoholic beverages, with a finished equilibrium pH greater than 4.6 and a water activity (aw) greater than 0.85." Part 114 governs commercial processors of acidified foods; low-acid canned foods fall under part 113, which is not described here.
law.cornell.edu 