Buttermilk is often used in baked goods, extra-crisp fried foods, salad dressings and even while making pancakes and waffles, while it may sound like an easy ingredient to procure from stores, it is the trickiest. The ingredient is seldom available in India in its original form, I usually find the spiced variation which is impossible to use in recipes. If you do end up finding a store-bought version that serves the purpose, storing it is a nightmare and the leftover often ends up going bad before you can use it again.The Anatomy Of ButtermilkReal buttermilk is the leftover liquid after churning butter from cultured cream. What we find in stores is cultured buttermilk made by adding bacteria culture to milk, heating it and then fermenting it for approximately 12 hours.Buttermilk contains more protein per cup than milk and is low in fat and calorie content. It is also high in calcium, vitamin B12, and potassium. And because it contains live cultures, like yoghurt it is easily digestible than milk.What Role Does It Play In Recipes Buttermilk is high in acid content which reacts with the bi-carbonate of soda, creating bubbles resulting in the perfect light and fluffy texture of baked goods. In salads, it acts as an agent that gives the end product a slightly tangy and a more multifaceted flavour. It is also used in marinades for chicken, as it makes the meat tenderer and also adds flavour.Making Buttermilk At HomePersonally, I never bother looking for store-bought buttermilk, ever since I learnt that you can easily make it at home. The best part you can use any milk you prefer, including plant-based milk. If you've decided to give this a try, here are three methods for doing so.#1 Using Lemon Or Vinegar Take the same amount of milk as you need buttermilk in your recipe. Stir in 3 teaspoons of either lemon juice or vinegar for every 1 cup of milk. If using vinegar it is best to use white vinegar.For example:1/4 cup milk will require teaspoon Lemon juice/vinegar1/3 cup milk will require 1 teaspoon Lemon juice/vinegar1/2 cup milk will require 1 teaspoons Lemon juice/vinegar2/3 cup milk will require 2 teaspoons Lemon juice/vinegar3/4 cup milk will require 2 teaspoons Lemon juice/vinegar Let it stand for 10 minutes. Once the texture shows some curdling the buttermilk is ready to use.#2 Using Cream Of Tartar Take the same amount of milk as you need buttermilk in your recipe. Add 1 teaspoon of cream of tartar per cup of milk. (Make sure your cream of tartar has not expired) Stir well and let it stand for 10 minutes before using#3 Using Yoghurt Or Sour Cream If using yoghurt, combine equal parts plain yoghurt and milk together. If using sour cream, combine equal parts sour cream and water together. Mix well and let it stand for 10 minutes before using.Storing ButtermilkAlways store buttermilk in an airtight glass bottle in the refrigerator. Homemade buttermilk should easily last for 7-10 days. You can also freeze it for up to 3 months.