Non-destructive testing technology for raw eggs freshness: a review

Abstract

Abstract: Raw egg freshness indexes mainly include sensory indicators, air cell height, Haugh unit, pH value, yolk index, specific gravity of eggs and total volatile basic nitrogen content. Traditional methods can test only part samples with low efficiency. This paper reviews the application of visible/near infrared spectroscopy, machine vision, electronic nose, dielectric properties and low-field nuclear magnetic resonance (LF NMR) for new non-destructive testing of egg freshness. We analyze advantages and disadvantages of each technology, and focus on the application of LF NMR technique in this field. Finally, existing problems and future directions are proposed to provide useful information for further research. Graphic abstract: [Figure not available: see fulltext.]