Infusing is a process that involves transferring flavors, aromas, or other properties from one substance (such as herbs, fruits, or spices) to another (usually a liquid base like oil, water, or alcohol). This technique is commonly used in cooking, mixology, and even in the production of cosmetics and fragrances.

The science behind infusing lies in the principles of diffusion and osmosis. Diffusion is the movement of particles from an area of higher concentration to an area of lower concentration. Osmosis, on the other hand, is the movement of solvent molecules through a semipermeable membrane to equalize the concentration on both sides.

When infusing, the substance being infused (often referred to as the "infusion agent") releases its volatile compounds, such as oils and flavors, into the liquid base. This happens due to the difference in concentration between the infusion agent and the liquid. The volatile compounds in the infusion agent move from an area of higher concentration to an area of lower concentration in the liquid base, resulting in the transfer of flavors and aromas.

For example, let's consider the process of infusing herbs into oil. When fresh herbs like rosemary or basil are added to oil, the volatile oils and flavors present in the herbs start diffusing into the oil. Over time, the oil becomes infused with the essence of the herbs, creating a flavored oil that can be used in various culinary preparations.

Infusing can also be achieved by heat. Heat increases the movement of particles, allowing for faster diffusion. For instance, when making a hot tea infusion, pouring hot water over tea leaves or herbs accelerates the infusion process, resulting in a quicker release of flavors and aromas.

References:

• Smith, A. (2018). The Science of Infusing Flavors. In Science & Cooking: A Companion to the Harvard Course. Retrieved from https://www.scienceandcooking.com/science/basics/infusing-flavors
• McGee, H. (2004). On Food and Cooking: The Science and Lore of the Kitchen. Scribner.