2.2. Fruit samples preparation
Samples of fresh-cut kiwi fruit [Actinidia deliciosa (A. Chev.) cv
Hayward], pineapple [Ananas comosus (L.) Merr.] and cantaloupe
melon (Cucumis melo L. var. reticulatus Naud.) were bought from
‘‘C & G s.r.l. Company’’ (Monserrato, southern Sardinia, Italy). The
produce was processed following HACCP guidelines (CAC, 1993).
All raw fruits were of the highest quality class, harvested at a ripe
maturity stage, cleaned before processing in a 200 ppm NaClO
solution for 2 min, and rinsed with tap water. Pineapple and melon
were manually peeled and sliced while kiwi fruits were mechanically
peeled. Then fruits were cut in trapezoidal sections. After processing,
pieces were washed with tap water and dried by a slight
centrifugation in order to remove microorganisms and tissue fluids,
thus reducing microbial growth and enzymatic oxidation during
subsequent storage. Samples of 100 g of fruit pieces (each
species separately) were packaged in see-through resealable polypropylene
trays for foodstuffs, and left overnight at 3 C.
The day after processing (day 1), samples were transported at
3 C to the laboratory by a refrigerated truck early in the morning.
On arrival, fruit of each species were segregated into three
groups. The fruits of the first group (GROUP 1, control) were stored
at 3 C for 5 days (recommended storage conditions). Fruits of the
second group (GROUP 2) were stored at 20 C for 6 h at day 1 to
simulate a cold chain interruption, and then re-stored at 3 C until
the expiration date (day 5). Six hours was the estimated time for
moving samples, covering the distance from the Company to all
the markets along the scheduled itinerary. It was also the time
needed to deliver the samples to our laboratory. Fruits of the third
group (GROUP 3) were kept under simulated shelf life at 20 C for
5 days to favour a rapid product deterioration.
2.3