Velp Scientifica
– UDK139 Operating Manual
10004762/B5
106
Distillation time = 5 minutes
Steam = 100%
Push START to initiate the cycle
Collect 150ml of distillate.
To avoid damage to the distillator it is strongly recommended NOT to use the
“removal of the distillation residues” function.
4) Titration:
titrate the distillate, containing 4 drops of phenolphthalein 1%, up to a
persisting pink colour, using the 0.1N NaOH solution.
5) Computation:
the sample volatile acidity is expressed as acetic acid in 100g of sample; 1ml of
NaOH 0.1N corresponds to g 0.006 of acetic acid:
g of acetic acid/100 g of sample = 0.6 x ml NaOH 0.1N / g of sample
NOTE:
at the end of the analyses, perform 3 washing cycles of the distillator.
Introduce in the test tube 150-200ml of distilled or deionised water and set for each
washing cycle 5 min for the distillation time. The aim is the complete removal of
traces of sample from the glass splash-head.
References:
-
Commission Reg. (EEC) No 1764/86, “Minimum quality requirements for tomato-
based products eligible for p
roduction aid”.
- SSICA-
Stazione Sperimentale per l’Industria delle Conserve Alimentari-Parma-Italy,
monography “The tomato”, pag. 156 “Quality control of the tomato preserves” (Italian
language)
- Books of Food Chemistry, R. Giuliano and M.L. Stein, Bulzoni Ed.-Roma-Italy, 5°
vol. ALIMENTARY PRESERVES, pag. 119 “Analyses of the tomato preserves”
(Italian language).
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