According to Proctor and Gamble washing powder can blow up! Manufacturers are encapsulating perfume oil in starch powder. But some of the oil leaks through the starch and spreads thinly over the large surface area of the fine particles. That can create an explosive fuel mix.

P&G’s researchers patented their solution in over 100 countries. The trick is to mix starch, orange oil and water, and then drive down the pH with citric acid while vigorously vibrating the mix. The result is an emulsion like oil-and-vinegar salad dressing. When this emulsion is sprayed into a hot oven it dries into fine particles with the oil safely trapped inside, eliminating the risk of explosion. And using citric acid has the bonus of a lemony smell that escapes with the orange aroma only when the powder gets wet in a washing machine, not when the box is opened.

Via New Scientist.