Gelatin is a soluble protein that can be added to different food products - Scottish Highers Chemistry - Question 8 - 2019

The weakest van der Waals' force between water and gelatin molecules is called London dispersion forces.

1. The student should first dissolve the gelatin in a small volume of water to ensure it is fully hydrated.
2. Next, they should transfer the gelatin solution quantitatively to the volumetric flask, using rinsings or washings to ensure no residue remains in the original container.
3. Finally, they should fill the volumetric flask to the mark with distilled water, ensuring that the total volume is exactly 100 cm³.

Based on the viscosity data for different concentrations, it can be predicted that the viscosity for a 10.0% gelatin solution would be approximately 11 units.

The rate of hydrolysis is reduced when pineapple is cooked because the heat denatures the enzymes, altering their shape and functionality. As a result, the bromelain enzymes cannot effectively catalyze the hydrolysis reaction of the gelatin.

To provide 500 mg of bromelain, and knowing the flesh from a pineapple contains between 13 mg and 29 mg of bromelain per gram, we calculate the mass as follows:

• Minimum: $ext{Mass} = \frac{500 ext{ mg}}{29 ext{ mg/g}} \approx 17.24 ext{ g}$
• Maximum: $ext{Mass} = \frac{500 ext{ mg}}{13 ext{ mg/g}} \approx 38.46 ext{ g}$ Thus, approximately 17.24 g to 38.46 g of pineapple flesh is needed.