To remove fat and food stains, you must use soap that can dissolve fat. The best alternative we have found for wool is lemon soap. In Norway, we recommend På Stell. It can be found as a spray or a bar of soap. This stain remover won't damage the wool fibers, and efficiently dissolves fat stains.
You won't always have lemon soap available when spills occur. In these cases, the best alternative is to use dish soap. Dish soap is also a good solution for the worst fat stains. Note that dish soap often contains enzymes that can damage the fibers if it is used often.
The most efficient method of removing fat and food stains is to use the sink. Use stain remover (lemon soap or dish soap) on the spot and put the garment below the faucet. The water should hit the stain directly so that it is running from the inside and out. In other words, the stain should disappear the same direction it came from.
Usually, stains can be dissolved in warm water, but there are exceptions. Carbohydrates like starch, and proteins like egg, milk and blood can be dissolved in cold water. On these types of stains you must avoid warm water, as this makes the stains set into the material. Inspect the stain to figure out the correct method and temperature.