Abstract: Colorimetric sensors attached to food packaging and exposed to the packaging headspace allow supply chain managers and consumers to monitor food freshness and expected shelf life based on food condition without unsealing containers or relying on the human senses of smell or taste. A gas-permeable membrane prevents direct food contact with sensor material, and color changes indicate increased concentration of volatile organic compounds generated during spoilage of the food spoilage. Color change may be read by machine or eye. One application uses silicon dioxide nanoparticles coated with Schiff's reagent and embedded in milk carton screw caps to detect spoilage to address variations in shelf life due to temperature abuse within the distribution system.

Abstract: A food product suitable for human consumption, having acceptable flavor and nutritional value, is recovered from cereal grain residues remaining after alcohol fermentation. The food product of the invention is produced by controlling the pH at a range of 4.0-5.0 of the various enzymic conversions of starch to alcohol using only certain organic and inorganic acids which avoid imparting unacceptable mineral acid tastes to the finished product. The preferred acid is citric acid. The pH of the slurry residues before drying to a finished product must be neutralized to about 5.0-8.0. Again, satisfactory taste of the finished product is achieved by carefully selecting the neutralizing agent, typically hydroxides or oxides of Na, K or Ca. Resulting products are characterized as containing only salts from acids used to adjust pH which are taste acceptable. The product forms a 1:10 aqueous suspension having a pH of about 5.0-8.0.