CRANFIELD UNIVERSITY Eleni Anthippi Chatzimichali ...

In brief, fresh deboned beef fillets were purchased from a meat market in Athens
(Greece) and transported under refrigeration to the laboratory within 30 minutes.
Upon arrival, the samples were prepared by cutting the beef fillets into pieces with
dimensions of 40mm wide, 50mm long and 10mm thick. After maintaining them for
an hour at 4C, the samples were subsequently placed in 90mm Petri dishes and
stored in high-precision incubation chambers (±0.5C) where they were left to spoil at
0, 5, 10, 15 and 20C (Argyri, 2010). In case study 1, three experimental techniques
have been employed; namely, FTIR spectroscopy, HPLC and e-nose.
2.2.1.2 Sensory Analysis
Sensory evaluation was performed during storage according to Gill and Jeremiah
(1991) by a sensory panel of five trained staff members (staff from the laboratory)
(Argyri, 2010). The assessment process was conducted under controlled conditions of
light, temperature and humidity. Sensory assessment was based on the perception of
colour and odour prior to and after cooking for 20 minutes at 180C in a preheated
oven, while taste was described solely/only after cooking (Argyri et al., 2010;
Panagou et al., 2010; Argyri et al., 2013). A meat sample, stored at -20C, freshly
thawed and cooked, was presented to the panel as a reference sample.
Each sensory attribute was scored using a three-point hedonic scale. The samples
were classified into three distinct categories: fresh, semi-fresh and spoiled samples.
Fresh samples were characterised by bright colours, typical of fresh oxygenated meat,
and the lack of any off-flavours (Papadopoulou et al., 2011). For the semi-fresh
samples, the formation of off-flavours was perceptible, but the samples were still
considered of acceptable quality. Finally, a persistent dull or unusual colour, in
addition to the presence of unacceptable off-flavours and putrid, sweet, sour or cheesy
odours were considered indicative of microbial spoilage and the samples were
classified as spoiled (Argyri et al., 2013). The integer values 1, 2 and 3 were used to
describe fresh, marginal (semi-fresh) and unacceptable (spoiled) samples respectively.
Score 1.5 was later introduced to indicate the first sign of meat spoilage.
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