In the 1970s, Heinz built an entire advertising campaign around its super-thick, friction friendly ketchup. The campaign borrowed Carly Simon's hit "Anticipation" and extolled the virtues of a "taste that's worth the wait."
Apparently, the food-service industry doesn't think the waste is worth the wait. Ketchup, mustard, mayonnaise and barbecue sauce that can't be coaxed from bottles mean lost revenue to restaurant owners and families trying to stretch their grocery budgets. About 1 million pounds (453,592 kilograms) of stuck-on sauces and dressings get thrown out each year worldwide, according to the Varanasi Research Group, a team of mechanical engineers and nanotechnologists at the Massachusetts Institute of Technology. Then there's the issue of the big cap required to get condiments out of squeeze bottles. Eliminating the need for such a big cap would reduce how much plastic goes into a single bottle, which could keep 25,000 tons of petroleum-based products out of the waste stream each year [source: LiquiGlide].
The same condiment-crazy MIT team has a solution: coat the inside of bottles with a unique material that prevents ketchup, mayonnaise or any other type of sauce from sticking to the surface. Most similar coatings contain nanolubricants you might not want to ingest, but the Cambridge folks developed a food-safe material that they say is completely tasteless and nontoxic. They call it LiquiGlide and describe it as a "structured liquid" -- rigid like a solid, but slippery like a liquid. Smear the inside of a condiment bottle with LiquiGlide, and the contents slide out like, well, poop from a goose.