Examination of rheological and physicochemical characteristics in Lithuanian honey

Abstract

The aim of the study was to determine the effect of the biological origin and temperature on rheological and physicochemical characteristics of honey. The honey of the selected varieties differed in color, scent, microstructure, total acidity, moisture, and pH. The level of moisture statistically significantly correlated with the rheological characteristics. The highest total acidity was a characteristic of forest and buckwheat honey, and the lowest of acacia honey. The lowest pH value (3.76) was found in forest and rape honey, and the highest in eucalyptus honey. Moisture levels significantly correlated with the rheological characteristics. All varieties of honey at all the studied temperatures were characterized by properties of non-Newtonian substances. The study showed that the effect of temperature on rheological characteristics of different types of honey varied and was more pronounced in honey with a crystalline structure, and less pronounced in non-crystalline honey.

Texture characteristics of raw rapeseed honey after storage at room temperature or freezing and heating up to 50°C

“…The values of the complex viscosity of the analysed media are similar to the values of the dynamic viscosity for instance, the relative differences between the average values of dynamic viscosity and complex viscosity for rape honey was 3.2% (Bakier et al, 2016). Stelmakienė et al (2012) reported significant differences in the rheological properties (thixotropy and consistency index) of Lithuanian commercial rapeseed honey, between the temperatures of 30 and 40°C, as well as between 30 and 50°C, contrary to present results. Interestingly, on the one hand, Lithuanian rapeseed honey exhibited at 30°C the highest consistency coefficient compared to other honey varieties, and it also showed elastic properties.…”

“…Interestingly, on the one hand, Lithuanian rapeseed honey exhibited at 30°C the highest consistency coefficient compared to other honey varieties, and it also showed elastic properties. On the other hand, at temperatures of 40 and 50°C it demonstrated pseudoplastic substance properties (Stelmakienė et al, 2012). At the highest temperature (50°C) used in the present study, the average values of the investigated textural properties were 64.74 g, 0.67 mJ, 26.51 g, and 14.16 g, respectively.…”

“…In contrast, Dobre et al (2012) reported non-Newtonian flow for rapeseed honey from Romania, which was additionally correlated with a high concentration of carbohydrates (78.3%). Similarly, other authors reported a typical crystalline structure for rape honey from Germany and Lithuania and, simultaneously, a non-Newtonian semisolid behaviour (Smanalieva and Senge, 2009;Stelmakienė et al, 2012). Bakier (2006) reported dynamic viscosities a b ranging between 11.4 and 16.9 Pa s for Polish rape honey measured between 19.85 and 21.85°C.…”

Rheological Modeling of the Effects of Adulteration on Nigerian Honey

“…They suggested that at very low shear rate, similar to those employed in this work, blood exhibits shear thinning behaviour, but as shear rate increases, the non-Newtonian behaviour gradually diminishes. Stelmakeiene and coworkers, [19], Cohen and Weihs, [20], Mossel and coworkers, [21] and Munro, [22], all reported that honey exhibited thixotropic rheological behaviour. However, this is contrary to Zaitoun and coworkers [23], who concluded that honey exhibits Newtonian behaviour.…”

“…From the rheograms (Figure 3), it can be observed that honey turns completely Newtonian from 10% adulteration with water. Other studies also show that adulterating honey with water leads to fermentation of the monosaccharides in honey leading to sour taste [19]. For better understanding of the rheograms, curve fits were carried out using both the newly derived Structural Kinetic model and the amended Carreau Yasuda model.…”