SIMPLE AND FAST DETERMINATION OF

II WORKSHOP ON CHEMICAL SENSORS AND BIOSENSORS
SIMPLE AND FAST DETERMINATION OF LACTOSE AND
LACTULOSE IN RAW AND UHT MILK USING
DIFFERENTIAL PH-TECHNIQUE
Silvia De Vita*, Nicoletta Luisetto*
Costante Pinelli**, Evaristo Dalla Turca**
*EurochemTecnologie Analitiche - I-00040 Via Pontina Km.34 Ardea, Rome
**Parmalat S.p.A. - I-43044 Via Milano 1- Collecchio, Parma
Abstract: A simple and fast method for the determination of Lactose
and Lactulose has been evaluated. The method is based on the
correlation of pH differences, measured with a glass electrode,
generated by H+ or OH- produced in the medium by enzymatic reaction.
The result, obtained determining Lactose and Lactulose were compared
with HPLC. The procedure based on the differential pH-measurements
has been found to give results comparable to that of official method.
The precision obtained using the two procedures was not significantly
different. The proposed method is resulted simple and fast (less then 4
minutes) , particularly for the lactulose evaluation considering no
sample pre-treatment is required for measurements which are also
automatically recorded. We suggest using the proposed method, based
on differential pH-technique, for routine determination of Lactose and
Lactulose in raw and UHT process treatment.
Keywords: Lactose, Lactulose, Milk, Differential pH
Name & address for correspondence:
Silvia De Vita, R&D department
Eurochem Tecnologie Analitiche – I – Ardea - Rome
Email:[email protected]
Phone:+39 06 91 47 164; Fax:+39 06 91 47 118
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