Thoroughly rinse your shrimp shells and heads under cold water to remove any impurities or sand particles. Pat them dry with a paper towel.
Heat the vegetable oil in a large stockpot or Dutch oven over medium heat. Add the shrimp shells and heads to the pot and sauté them for about 5-7 minutes until they turn pink and release their aroma. Stir occasionally to prevent burning.
Add the chopped onion, carrots, celery, garlic, bay leaves, whole black peppercorns, and salt to the pot. Sauté for an additional 3-4 minutes to allow the vegetables to soften slightly and for the flavors to develop.
Pour in the water, making sure it covers all the ingredients in the pot, and bring the mixture to a boil over high heat.
Once the stock comes to a boil, reduce the heat to low and simmer gently for 30-45 minutes. This slow simmering process allows the flavors from the shrimp shells and vegetables to infuse into the stock.
As the stock simmers, skim off any foam or impurities that rise to the surface using a slotted spoon or a fine-mesh sieve to ensure a clearer and cleaner stock.
After simmering, remove the pot from the heat and let the stock cool for a few minutes. Strain it through a fine-mesh sieve or cheesecloth into a large bowl or another pot, and discard the solids.
Allow the shrimp stock to cool completely before transferring it to storage containers. You can divide it into portions that suit your needs.
You can use your shrimp stock as a base for soups, stews, sauces, risotto, or any recipe that calls for seafood or fish stock. It adds depth and richness to dishes and enhances the overall seafood flavor.
Homemade shrimp stock can last in the refrigerator for up to 4 days and in the freezer for up to 4 months.