Dishwash Bar

Details

The bar is still the most honest way to wash vessels in most Indian kitchens: it is cheap, it does not spill, and it wastes nothing. IS 6047 is the BIS specification for scouring products for utensil cleaning in powder, paste and bar form, and the two figures it turns on are the ones nobody prints. The first is active matter, the percentage that is actually surfactant. Ours is 14 percent, measured by cation titration. A bar at half that simply needs twice the rubbing, which is why a cheap bar wears down in a fortnight and feels like it never lathers. The second is the abrasive, and here the important number is not how much but how hard. Our abrasive is graded calcite at Mohs 3 hardness and a median particle size of 40 microns. Stainless steel sits at Mohs 5.5 to 6, so calcite cuts baked carbon and cannot scratch the vessel. The market bar is filled with whatever mineral is cheapest by the tonne, at an unstated hardness, and a filler harder than steel is how a thali stack acquires its fine grey haze.

• Active matter 14 percent, and the surfactants are named: sodium linear alkylbenzene sulphonate 10 percent, sodium C12-14 alkyl polyglucoside 4 percent
• Abrasive 34 percent, graded calcite, Mohs 3, median particle 40 microns. The rest is soda ash, a sodium silicate binder and the salt matrix that holds a bar together, and moisture is under 12 percent so the printed weight is bar and not water
• Measured pH 10.2 in a 1 percent solution at 27 C. It is alkaline, because that is what lifts fat, and a dishwash bar sold as pH neutral is either not working or not telling you
• It rinses clean, and that is the part the category never mentions, because surfactant left on a plate is the actual risk in a dishwash product. A vessel washed and rinsed under 5 litres of running water carries under 0.1 mg of anionic surfactant, measured as methylene blue active substances to APHA 5540 C on the swab extract
• The honest limit on that: a bar rinses clean in running water and it does not rinse clean in a still bucket. That is true of every dishwash product sold, ours included, and it is the reason a final rinse under the tap is not optional
• No synthetic dye, no perfume, no chlorine bleach, no phosphate, no triclosan, no quats
• No preservative, because at under 12 percent moisture the water activity will not support growth
• Pressed hard, so it holds its shape in a wet tray instead of turning to slush, which is the commonest complaint about a dishwash bar
• No germ-kill claim is made. This is a cleaner. A claim to kill anything needs a named organism, a stated contact time and a test such as EN 1276 at an accredited microbiology laboratory, and we have not run one
• Keep it off non-stick and anodised aluminium, where any abrasive will dull the surface. Use the gel for those
• At about 2 g a sink it gives roughly 75 sinks of vessels a bar, which is Rs 0.60 on the single bar and Rs 0.50 on the pack of 6