Non-destructive determination of chemical and microbial spoilage indicators of beef for freshness evaluation using front-face synchronous fluorescence spectroscopy

Food Chem. 2020 Aug 15:321:126628. doi: 10.1016/j.foodchem.2020.126628. Epub 2020 Mar 17.

Abstract

We investigated the potential of front-face synchronous fluorescence spectroscopy (△λ = 75 nm) to non-destructively evaluate beef freshness and quality decline during chilled storage. The total volatile basic nitrogen (TVB-N), thiobarbituric acid reactive substances (TBARS) and total viable count (TVC) values were used as standard freshness indicators. The fluorescent substances, including amino acids, collagen and conjugated Schiff bases, were highly correlated with the chemical and microbial deterioration of the beef. Quantitative models for simultaneously predicting the three freshness indicators were built combined with partial least squares (PLS) algorithm and showed good reliability. For TVB-N and TBARS values, Rc2 and Rp2 were both above 0.900, and for TVC values Rc2 and Rp2 were 0.912 and 0.871, respectively. The qualitative model established by partial least squares discriminant analysis (PLS-DA) algorithm could accurately classify beef samples as fresh, acceptable or spoiled. The accuracy of the calibration and validation sets were 92.54% and 86.96%, respectively.

Keywords: Beef; Classification; Conjugated Schiff bases; Freshness indicators; Front-face synchronous fluorescence spectroscopy.

MeSH terms

  • Algorithms
  • Animals
  • Calibration
  • Cattle
  • Discriminant Analysis
  • Least-Squares Analysis
  • Nitrogen / chemistry
  • Red Meat / analysis*
  • Red Meat / microbiology
  • Reproducibility of Results
  • Spectrometry, Fluorescence
  • Thiobarbituric Acid Reactive Substances / chemistry

Substances

  • Thiobarbituric Acid Reactive Substances
  • Nitrogen