ST. LOUIS — Coin laundry owners looking for the newest vending possibilities should take a look at what was on display at the National Automatic Merchandising Association’s (NAMA) National Expo vending machine show held in St. Louis this month.The expo, which showcased the latest advances in vending and coffee machines, highlighted a variety of technologies presented as solutions to some common vending machine problems, such as treats stuck in machines and customers without enough pocket change.Some machines on display utilized infrared sensors to detect whether or not a snack has been dispensed. If stuck, the machines will try two more times to release the snack, and if that doesn’t work, it offers customers a chance to choose something else or a refund. Another technology allowed customers to use bills larger than $1, dispensing change in bills as well as coins.One machine used a robotic arm with a vacuum to retrieve ice cream from a cold storage chest. Another grilled hot dogs inside the machine, warmed the bun and dispensed packets of ketchup and mustard, resulting in surprisingly tasty hot dogs —soy dogs and kosher hot dogs are among the variations.Some machines included an electronic screen that displays the back of packages to show customers nutritional information.Another technology allowed parents to go online, view the contents of the vending machine at their children’s school, and limit which snacks and how many they’d like available to their kids. Students use an ID card or a PIN number to identify who’s at the machine and what they can purchase.NAMA spokeswoman Jackie Clark pointed out that the organization’s Fit Pick program is a way the vending industry is trying to provide healthier options. Items identified as Fit Pick foods have less than 35% fat, less than 10% saturated fat and less than 35% weight in sugar.One concept, not yet in production, would allow people to supply their own glasses or use recyclable cups to be filled with filtered, sparkling or flavored water.Coffee machines extended beyond the basic cup of coffee, with machines designed for single-serving packets, “well-being” teas or “indulgence” drinks such as hot chocolate.