Investigation of properties of sunflower and rapeseed oils obtained by the soxhlet and microwave extraction methods
Laen...
Kuupäev
2022
Kättesaadavus
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Estonian Academic Agricultural Society
Abstrakt
The main purpose of the study was to evaluate the possibility
of replacing hexane, which is traditionally used for the extraction of vegetable
oils, with ethanol as a safer solvent when extracting oil from sunflower meals
and rapeseed in the microwave field. Thus, the influence of the solvent type
on physicochemical characteristics of oil and the low-fat meal was studied.
The main indicators of the composition and quality of sunflower and rapeseed
extraction oil were studied. The quality of oil and ways of its use in food
products are mostly determined by its fatty acid composition. Analysis of the
fatty acid composition of the oil was performed by the method of gas
chromatography using a column HP-88 100 m* 0.25 mm*0.20 µm. The
possibility of using oil in food was established by conducting pilot laboratory
studies and investigating changes in physicochemical parameters during
storage. The extraction by the Soxhlet method (hexane as a solvent) was
compared with the method of extraction of raw materials in a microwave field
(ethyl alcohol as a solvent). Studies of physicochemical parameters indicate
the degree of oil oxidation (determination of peroxide and anisidine values).
The peroxide value is an indicator of the content of primary oxidation
products. The peroxide value of the oil obtained by the method of Soxhlet
extraction (hexane as a solvent) was 5.0 (½O mmol) kg–1
. The peroxide value
of the oil obtained by extraction in a microwave field (ethyl alcohol as a
solvent) was 3.8 (½O mmol) kg–1
. The anisidine value is an indicator of the
content of aldehydes in vegetable oils (secondary oxidation products). The
anisidine value of the oil obtained by the method of Soxhlet extraction (hexane
as a solvent) was 0.3 s.u. The anisidine value of oil obtained by extraction in
a microwave field (ethyl alcohol as a solvent) was 0.2 s.u. Comparing the data
of peroxide and anisidine values, it can be argued that the oil obtained by
extraction of raw materials in a microwave field (ethyl alcohol as a solvent)
had the best indicators. The acid value is one of the main qualitative indicators
that characterize the degree of oil freshness. The acid value of the oil obtained
by the method of Soxhlet extraction (hexane as a solvent) was
3.1 (mg KOH) g
–1
. The acid number of the oil obtained by extraction in a
microwave field (ethyl alcohol as a solvent) was 2.1 (mg KOH) g
–1
. A
comparison of the acid values of oils extracted from the raw material by
different extraction methods shows that the oil obtained by the method of
extraction of raw materials in a microwave field using ethyl alcohol as a
solvent has the best acid value. Studies have shown that the oil, which was
obtained by extraction of raw materials in a microwave field using ethyl
alcohol as a solvent, had the best resistance to oxidation during storage (three
months).
Kirjeldus
Saabunud / Received 01.02.2022 ; Aktsepteeritud / Accepted 15.04.2022 ; Avaldatud veebis / Published online 15.04.2022 ; Vastutav autor / Corresponding author: Valentyna Bandura ; bandura_3@ukr.net
Märksõnad
sunflower and rapeseed oil, extraction, microwave energy supply, Soxhlet, fatty acid composition of oils, articles