2.3. Fruit weight losses, total soluble solids and titratable
acidity.
Fruit weight losses were measured on 60 polyethylene boxes or punnets of
200 g of fruit equipped with inlet-outlet ports for each storage
condition, using analytical balance. The weight was monitored on the
same boxes all along the distribution chain: early and late phases of LT
and during SL for 1 and 2 days following 7 days of cold (LTA and LTC).
Three replicates per treatment (10 berries per sample) were ground in an
electric juice extractor. The obtained clear juice without achenes was
used for the determination of total soluble solids (TSS), pH-value and
titratable acidity (TA). TSS was measured using a digital and
temperature-compensated refractometer (Atago, Co, Tokyo, Japan) that
detects reducing sugars and other soluble compounds. In the juice of
strawberry fruit, the pH-value was determined with a pH meter.
Titratable acidity was determined by tritration with 0.1 N NaOH to pH
8.1 (Mettler DL-70, Mettler –Toledo, Spain) and the results were
expressed as citric acid equivalents, which is the main organic acid in
strawberry fruit, and expressed per fresh weight.