Band 21, Heft 3

Honey products adulterated with syrup need to be availably distinguished from the true ones and quantified by modern method, for instance three-dimensional fluorescence spectroscopy. The spectra from eight types of honey showed that a linear relationship existed between fluorescence intensity and honey solution concentration in two excitation wavelength ranges of 240–320 nm and 320–360 nm when honey was diluted to 1 % ( V : V ) or less. Based on the linearity, a way was proposed to estimate the purity of adulterated honey by employing the least squares model to compare the spectra of adulterated honey with honey and syrup on a computer, after they were properly diluted. Honey artificially mixed with syrup in a ratio of 3:7 ( V : V ) was evaluate to be 31.6 % and the error was only 1.6 %. The method of quantitation on adulterated honey has the characteristics of convenience and accuracy.

In this study, ammonium glycyrrhizate (AG) based curcumin (Cur) nanocomplexes (AG/Cur NCs) were prepared. Water solubility of Cur and the physical stability of AG/Cur NCs under varying conditions were investigated, and the stability and bioaccessibility of Cur during in vitro digestion were also studied. The results showed that Cur solubility and physical stability of the NCs increased significantly ( p  < 0.05) with the increase of AG concentration. The solubility of encapsulated Cur and the physical stability of AG/Cur NCs were affected by the changes in pH, salt concentration, and temperature, but the NCs showed good stability against various environmental conditions. After in vitro simulated digestion, the stability and bioaccessibility of the embedded Cur in the NCs were 6.54 % and 21.70 % respectively, higher than that of free Cur. The formulation of AG/Cur NCs significantly enhanced the solubility and stability of Cur, indicating substantial promising for Cur-based functional foods.

In this work, high pressure homogenization treated soy 7S protein (HPH–7S) was employed as carrier to load and delivery VD3. The encapsulation efficiency (EE) (97.88 %) and bio-accessibility (85.69 %) of VD3 was markedly improved by HPH-7S as compared with that of untreated 7S protein (92.63 %, 73.36 %), while the particle size (80.1 nm) was prominently smaller than that encapsulated by untreated 7S protein (243.3 nm). The photochemical and thermal stability of VD3 in VD3@HPH-7S nanoparticles (VD3@HPH-7S-NPs) was superior to that of VD3 protected by 7S protein. The enhancement of delivery capacity of HPH-7S may be due to the change in protein structure. i.e. the peptide chains of the proteins unfolded during homogenization treatment, exposing more hydrophobic groups and rearranging the tertiary structure, which was verified by Fourier transform infrared, endogenous fluorescence spectrum and surface hydrophobicity.

In the present work, impacts of microwave and oven drying on the drying, rehydration, and fermentation kinetics of kefir grains as well as on the microbial viability of grains were investigated. Kefir grains were dried at various oven temperatures (30 °C, 37 °C, and 45 °C) and microwave powers (100 W, 180 W, and 300 W). Microwave drying reduced the drying time by 90 % and water absorption capacity of grains dried by microwave is higher than those dried by the oven. Moisture diffusivity was observed to increase with drying temperature (0.4 × 10 −10 –1.7 × 10 −10  m 2 /s) and microwave power (3.2 × 10 −10 –17 × 10 −10  m 2 /s). The results indicated that drying methods and conditions do not affect the fermentation ability and the viability of kefir grains to a detrimental extent. Compared to spray and freeze drying, the survival rate in microwave and oven drying (around 90 % for both LAB and yeast) was significantly high. As a result of the modeling studies, it was determined that the drying kinetics could be represented by the 1st order kinetic model (Lewis model) while the rehydration and fermentation kinetics could be represented by the pseudo 1st order kinetic model.

At the present time, among the avian eggs, especially the Chicken Eggs are the basic food items that are consumed extensively and therefore have a large marketing. Due to the fact that the egg content is packed naturally with a thin and fragile outer shell structure, a variety of precision transportation and packaging techniques are needed to be developed in order to reduce egg loss. In this study, a chicken egg is modeled in the mean dimensions discussed in the literature and mechanical behaviors at different drop angles are investigated using the finite element method. The study results are compared with each other to determine critical angles with respect to minimum and maximum stress values in order to create a source for transportation techniques and protective packaging designs.