A Simple Sensor System for Onsite Monitoring of O2 in Vacuum-Packed Meats during the Shelf Life.

Elisa Santovito,Joseph P Kerry,Malco C Cruz-Romero,Sophia Elisseeva,Dmitri B Papkovsky,Geraldine Duffy

doi:10.3390/s21134256

Abstract

Vacuum packaging (VP) is used to reduce exposure of retail meat samples to ambient oxygen (O2) and preserve their quality. A simple sensor system produced from commercial components is described, which allows for non-destructive monitoring of the O2 concentration in VP raw meat samples. Disposable O2 sensor inserts were produced by spotting small aliquots of the cocktail of the Pt–benzoporphyrin dye and polystyrene in ethyl acetate onto pieces of a PVDF membrane and allowing them to air-dry. These sensor dots were placed on top of the beef cuts and vacuum-packed. A handheld reader, FirestinGO2, was used to read nondestructively the sensor phase shift signals (dphi°) and relate them to the O2 levels in packs (kPa or %). The system was validated under industrial settings at a meat processing plant to monitor O2 in VP meat over nine weeks of shelf life storage. The dphi° readings from individual batch-calibrated sensors were converted into the O2 concentration by applying the following calibration equation: O2 (%) = 0.034 * dphi°2 − 3.413 * dphi° + 85.02. In the VP meat samples, the O2 levels were seen to range between 0.12% and 0.27%, with the sensor dphi signals ranging from 44.03° to 56.02°. The DIY sensor system demonstrated ease of use on-site, fast measurement time, high sample throughput, low cost and flexibility.

Highlights

Rising global production and consumption of meat over the past decade has introduced new challenges in the meat supply chain [1]
We present a constructed O2 sensor system designed for monitoring the residual O2 in vacuum packaging (VP) raw beef cuts and quality assessment of these products during their shelf life by means of disposable, low-cost, in-house-made sensors
The maximum recovery diluent (MRD), plate count agar (PCA), nutrient broth (NB), de Man, Rogosa and Sharpe agar, MRSA and PVDF membranes were from Sigma-Aldrich (Dublin, Ireland)

Summary

Introduction

Rising global production and consumption of meat over the past decade has introduced new challenges in the meat supply chain [1]. Like all perishable foods of animal origin, fresh meat is susceptible to microbial contamination and spoilage and related processes like lipid oxidation, sensory and quality degradation, which occur at different stages of the production chain including preparation, storage and distribution [2]. By reducing the exposure of meat to ambient oxygen, vacuum packaging (VP) helps to preserve the organoleptic properties of the product and reduce microbial growth and other spoilage-related degradative processes [8]. VP is a common packaging method in the meat industry, especially for the transport and sale of fresh meat products, preservation of quality and extension of their shelf life up to 55 days. VP helps preserve colour, which is an important visual quality of raw meat used by consumers at the point of sale [13], and oxygen-dependent meat browning leads to significant rejection of the product by consumers [14,15]

Methods

Results

Conclusion