Fruits and vegetables used in canning are picked at peak freshness, ensuring the best flavor and nutrient quality. Because canning preserves nutrients, canned foods can be as nutritious as fresh and frozen foods. The amount of minerals, fat-soluble vitamins, protein, fat, and carbohydrates remains relatively unchanged by the canning process while exhibiting a very long shelf-life.

The Need

Enamel-lined cans are essential for the food industry as food can be stored longer while enhancing taste. Additionally, the enamel helps prevent the metal from rusting, maximizing the shelf life. The Enamel Rating Test (ERT) is widely used as a quality control tool for food canning applications as it is quick and inexpensive. However, research indicates that the ERT is insensitive to low coating defects, impactful coating performance, and quality.

The Technology

This technology is an electrical impedance test (EIT) for evaluating the integrity of the enamel of canned foods. Cans are filled with NaCl and then subject to a sinusoidal voltage separating high and low impedance. Using these data, the system can accurately establish the integrity of the enamel in the can, even with small defects. The inventors created an advanced prototype and established proof of concept within the laboratory.

Commercial Applications

Commercial canned food packagers and suppliers can use this test to ensure the quality of canned food linings.

Benefits/Advantages

Existing ERT testing methods are insensitive at low defect levels. This invention is a non-destructive method for detecting tiny defects in coatings and improving the quality of canned food.