Osmotic Respiration Lab Report
For the effectiveness of diffusivity, Fick’s equation was used (5) to estimate the dehydration kinetic of different osmotic conditions.
M.R=((M_t-M_e)/(M_0-M_e ))=〖8/π^2 e〗^((-(π^2 Dt)/(4L^2 )) ) …(5)
Where D is the effective diffusivity, and L is the length of the (cubical) sample. Results and discussion
3.1. Samples and solvents prepared
In this section all results will be presented and discussed in details. It should be mentioned that the apples pieces, unlike the carrots, were exhibiting browning effects changing their color during the cutting and peeling session and before placing them into the solutions. Also, an important observation that some of the solutions took long time to fully dissolve, for instance, the sugar > 6 hours prior the experiment, and this was not the case in the salt.
3.2. Moisture content In this experiment, two setting were conducted to see the osmotic agents and temperatures effect. Figure 1 below shows both effects on the products. Figure 1. Shows two products’ moisture content (lines are not …show more content…
The apples’ and sugar solutions’ water activity were recorded during 6 hours as shown in figure 3. However, it was clear that the water activity of the saturated solutions still lower than apples aw. The difference can be seen in the initial Aw measurement where at least 0.05 to 0.06 different of aw. The apples’ samples aw was close to 0.97 where the average of the solutions’ aw was 0.91. An interesting observation that there was no reduction in the aw except in the apples samples that immersed in 35 °C water bath. The temperature here helped the osmatic dehydration to take place, whereas the time has very small impact on the whole