Detection of the Electrical Conductivity and Acidity of Honey from Different Areas of Tepi
Honey is the ingredient of most industrial products for sweetening and improving its food composition. The study is therefore based on the determination of physical parameters such as electrical conductivity and acidity. The instrumentation and apparatuses used in the work are conductometry and titration apparatuses. Honey samples obtained from different areas with respect to Tepi town have been analyzed and the result obtained is on the basis of conductometry and acidity measurement. Hence 20g of each anhydrous honey sample was weighed and dissolved in 100mL of deionized water in order to prepare 20 %( w/v) solution to measure conductivity. The acidity is detected after 10g of each honey sample is dissolved in 75mL of deionized water. The conductivity in summer honey determined to be 0.097mS/cm, 0.153mS/cm 0.117mS/cm and 0.337mS/cm in Korcha, Mexi, Sheko and Gobito respectively. Acidity is found to be 17, 28.67, 29 and 25miliequi/Kg. The conductivity in winter honey is detected to be 0.123, 0.186, 0.103 and 0.246mS/cm. The acidity in winter honey is 3.36-4.26 and 18.3-25.3meq/Kg from pH meter and titration respectively. The conductivity of darker honey is slightly greater than lighter honey, which indicated that the darker honey has more mineral content; and acidity of three honey samples is almost similar. The honey products are safe and fit the international honey commission standard and probably both darker and lighter honey are nutritionally important.
Honey and its physical parameters
e aim of this study was to find how close relations exist between the results of microscopic analysis, optical rotation and electrical conductivity in 55 honey samples from the Czech Republic. e obtained results were to be interpreted in relation to the classification of honey samples according to their origin (honey groups: blossom, honeydew and compound honey). e relations were positive, very close (r > 0.80) and very highly significant (P < 0.001). Several analysed samples would have been inserted into honey groups wrongly if only conductivity had been measured. is fact and high correlation coefficients evidence that exact classification of honey must be car - ried out not only by measuring the conductivity but also on the basis of optical rotation and microscopic analysis - namely in transition intervals of conductivity between the particular honey groups.
Classification of honeys by principal component analysis on the basis of chemical and physical parameters
Zusammenfassung18 chemische und physikalische Parameter der Nektar- und Honigtauhonige wurden bestimmt und die Ergebnisse statistisch mit Hilfe der Hauptkomponentenanalyse ausgewertet. Danach konnten die Honige in folgende Gruppen unterteilt werden: 1) Akazienhonige, 2) Rapshonige, 3) Linden-, Blüten-und Heidehonige, 4) Honigtauhonige. Zwischen dem Nektarhonig und Honigtauhonig lagen wahrscheinlich die Proben von Mischhonigen aus Blüten- und Waldtracht. Die bedeutendste erste Hauptkomponente war mit folgenden Parametern verbunden: elektrischer Leitfähigkeitswert und Aschegehalt, Gehalt an freien Säuren und Prolin sowie der pH-Wert und Diastasezahl. Aufgrund der Hauptkomponentenladungen und der linearen Korrelation kann angenommen werden, daß diese Parameter für die Honigklassifizierung von größerer Bedeutung sind als der Gehalt an reduzierenden Zuckern, scheinbarer Saccharose, Mono-, Di- und Trisaccharide, Glucose und Fructose. Die Klassifizierung der Honige mit Hilfe der Hauptkomponentenanalyse kann bei der Spezifikation einer Honigprobe aufgrund ihrer chemischen Zusammensetzung von Nutzen sein.SummaryEighteen chemical and physical parameters of nectar and honeydew honeys were determined and the results were analysed statistically by the method of principal component analysis. On the plots of principal component loadings, the honeys were divided into the following groups: (1) acacia honey; (2) rape honey; (3) linden, floral (nectar coming from various plants) and heather honeys; (4) honeydew honey. The samples which were a blend of nectar and honeydew honeys may be considered as a separate group between 3 and 4. The most important first principal component was strongly associated with the value of electrical conductivity, the contents of ash, free acids and proline, as well as with the pH and the diastase number. The principal component loadings and linear correlation suggested that these parameters contributed much more to the classification of honeys than apparent reducing sugars, apparent sucrose, mono-, di-, and trisaccharides, glucose and fructose. The classification of honeys by the method of principal component analysis may serve as an additional tool in specifying samples on the basis of their chemical composition.