What to Put in a Seasoning Jar Besides Salt, and What to Skip

Salt goes in the first jar, plain white sugar goes in the second, and the third should hold something you will finish inside a month. Deciding what to put in a seasoning jar besides salt comes down to one measured number: the humidity at which a dry crystal starts pulling water out of the air around it. Salt switches at 75.29% relative humidity, and a normal kitchen never gets close.

The trap is the jar that photographs best full. Seasoned salt, a barbecue rub, a cure mix of salt and sugar - a blend takes up moisture at a humidity below any single ingredient in it, so the mixed jar sets solid in the same room where the plain one stays loose. Houseland sells its ceramic set as 1 Jar, 2 Jar Set or 3 Jar Set at about 300 ml a jar, which is real counter space to hand to a powder that turns into a puck.

What can go in a seasoning jar besides salt?

Six candidates are worth the space, and one figure sorts them: the relative humidity at which the powder begins dissolving in the air, written RH0. Below it the contents sit unchanged for years. Above it they dissolve in what they have absorbed, then set hard when the room dries out again.

Hold on to the first row, because it is the whole reason an open salt pot works. A 2021 paper in ACS Omega measured sodium chloride at 75.29 plus or minus 0.12% RH on a dynamic vapour sorption instrument at 77 °F (25 °C). The US Environmental Protection Agency tells homeowners to keep indoor humidity below 60 percent, ideally between 30 and 50 percent. A kitchen inside that band sits some 25 points short of the humidity salt needs, which is why the same open pot that keeps salt loose ruins a rack of ground spice.

Why does seasoned salt cake when plain salt stays loose?

A blend takes up water at a humidity lower than any single ingredient in it, so seasoned salt cakes in air that leaves plain salt loose. The effect is called deliquescence lowering, and it is measured rather than argued about. ProUmid's application note on food blends defines it as dissolution at a relative humidity below the deliquescence point of the individual components, from sorption runs at 77 °F (25 °C) with humidity stepped up 1 percent at a time.

The size of the drop is what should change your shopping. Ghorab and colleagues, published in Pharmaceutical Development and Technology in 2013, watched crystalline sucrose deliquesce at a water activity of 0.845 on its own, then at 0.760, 0.781, 0.792 and 0.817 once blended with four maltodextrins. Read those as humidity: 84.5% for sugar alone, 76.0% for the worst pairing. The blend crosses over 8.5 points earlier, and maltodextrin is an ordinary carrier in a supermarket seasoning mix.

Allan and Mauer, writing in Food Chemistry in 2016, state the general rule in one line: blends of crystalline ingredients exhibit deliquescence lowering, giving a mixture deliquescence point lower than the individual ingredient values. A separate study of two-ingredient powder blends tied the caking itself to that shift, reporting that the reduced deliquescence point in deliquescent solid mixtures was found to cause caking, with glucose and citric acid welding into crystalline bridges as the water evaporated away again.

Caking is only the visible half of the bill. The same ProUmid note lists the rest: decreased solubility and bioavailability, changed appearance and sensory characteristics, and degradation of valuable ingredients like vitamins. Work on vitamins B1, B6 and C blended with fructose and held from 43 to 98% RH at 72 °F (22 °C) for up to 12 weeks found thiamin and ascorbate degradation significantly promoted above the deliquescence point. The jar that caked also quietly lost some of what you paid for.

Is white sugar actually safe in the second jar?

White granulated sugar earns the second jar, provided you accept that its failure mode is permanent. Utah State University Extension is blunt about it: store sugar in a cool, dry location, because moisture makes granulated sugar hard and lumpy and once this happens there is no easy method to restore lumpy sugar. It stays perfectly safe to eat. It simply stops behaving like sugar, and a food processor is the only real fix.

Ohio State's pantry chart gives granulated sugar 2 years covered tightly, and brown sugar 4 months in an airtight container. Brown sugar fails in the opposite direction, because the moisture that makes it soft is the thing that leaves, and a lid that only rests on top speeds that up. Leave the brown in its bag with a clip and give the glassware to the white.

One practical note on filling: the two do not weigh anything like the same. The FAO/INFOODS density tables list fine table salt at 1.38 g/ml against 0.7 g/ml for granulated sugar, so an identical pot holds roughly twice the weight of one as the other. Houseland lists each jar at about 300 ml, 4.1 in (10.5 cm) wide and 3.6 in high, with a 3.2 in (8.2 cm) spoon, which works out at a fortnight of salt for most cooks and rather less than a fortnight of sugar if you bake.

From the shop

Salt Cellar With Spoon, Ceramic Seasoning Jar With Bamboo Lid

Each jar holds about 300 ml and measures 4.1 in (10.5 cm) wide and 3.6 in high, with a 3.2 in (8.2 cm) spoon. Speckled ceramic body and bamboo lid, in 1 Jar, 2 Jar Set or 3 Jar Set.

View the ceramic salt cellar — 3 set sizes & current price

How do I choose what goes in the third jar?

Run five checks over any candidate and the third jar stops being a graveyard. Turnover does most of the work: a powder finished in a month never gets long enough in the room for a humid evening to matter.

1. Will you empty it inside a month? A pot refilled every three weeks never accumulates the humid hours that cake it.
2. Is it one ingredient rather than a mixture? A single crystal has a deliquescence point you can look up; a blend has a lower one nobody has published.
3. Is it bone dry to the touch? Moulds grow down to about 0.65 water activity while most bacteria need above 0.91, so the mould floor is the one that bites first in a dry-goods pot.
4. Does it carry oil or anything fresh? Both are out, for the reason in the next section.
5. Would you shrug at binning the lot? Saffron, vanilla sugar and a rub you paid $14 for belong in a sealed tin at the back of a cupboard.

What survives all five is dull on purpose: salt, white sugar, baking soda, and one rotating slot for whatever this month's cooking actually uses - sesame seeds, chilli flakes, cracked pepper from a bag you opened this week. It is the same test that decides an open shelf, where the things worth displaying turn out to be the things you handle, not the things that look furnished.

What should never go in an unsealed counter pot?

Ground garlic powder, onion powder, any homemade rub, anything oily, and anything holding a fresh ingredient. Garlic and onion powders are the ones people complain about, and the blends are the ones the physics rules out in advance. A rub is salt plus sugar plus ground spice: three soluble solids in intimate contact, which is the exact case where the mixture point lands below all three.

Oil is a different failure and a more serious one. Penn State Extension notes that herbs, garlic and other vegetables used to flavour oils are low acid foods and can be a source of Clostridium botulinum spores, and that surrounding them with oil creates the oxygen-free environment those spores want at room temperature. Their fresh-herb route is refrigerated and used within 2 to 4 days. None of that survives a pot that lives beside the hob.

Placement is the uncomfortable part of this answer. NDSU Extension's line is to keep spices in a cool, dry, dark place away from the oven, stovetop, microwave and dishwasher, which describes the opposite of a counter pot. That is the trade you are making, and it is a fair one for salt and baking soda, which have no aroma left to lose, and a bad one for paprika you chose carefully. Dry contents also keep the food-contact question simple, the way it stays simple for a coconut bowl until something wet or oily goes into it.

Shelf life settles the last argument. Ohio State gives ground spices 6 months airtight and whole spices 1 to 2 years; NDSU says use ground spices within two to three years and whole within three to four. The disagreement tells you these are quality windows rather than safety dates, and both assume a sealed container in the dark. An open pot on a sunlit worktop is at the short end of whichever range you trust. Nothing with flavour you would miss should go in it, which is the instinct that also decides what stays off a display ledge.

What I'd do

Salt first, white granulated sugar second, and the third jar on rotation against what you are cooking this month rather than what fills the gap. For a lot of kitchens that makes the 2 Jar Set the honest buy, with a sealed tin behind the cupboard door for everything with an aroma worth protecting.

If you do take the third jar, fill it from a bag you will finish, never from a blend. Houseland's set is offered as 1 Jar, 2 Jar Set or 3 Jar Set, and the two smaller options are not a downgrade - they are the version that matches how a covered but unsealed pot actually behaves. Empty and dry the jar between refills instead of topping up over the old layer, keep it a step back from the steam, and check it at a month. If the spoon meets resistance, the contents were never right for an open pot, and no lid was going to fix that. The rest of the kitchen and home range follows the same rule: dry things stay easy, wet things need a seal.

Shop kitchen & home from Houseland

-17%Stainless Steel Cutting Board, 304 Food-Grade, Double-Sided with Juice Groovefrom $49.99$59.99-14%Titanium Frying Pan, Uncoated, Induction Safe, with Tempered Glass Lidfrom $119.99$139.99Stainless Steel Finger Hand Protector, Knife Guardfrom $29.99-14%Kitchen Knife Sharpener, 3-Stage and 4-Stage Manual Pull-Throughfrom $29.99$34.99-20%Stainless Steel Bench Scraper and Dough Cutterfrom $29.99$37.49-22%Water-Seal Butter Crock with Lid, Reactive Glaze Ceramic Keeperfrom $69.99$89.99

See all kitchen & home →