Note: Everything needs to be clean and sanitize

Essentially all you need is cream and a jar. Of course you can make it in the mixer or the blender and here I usually make it from ripened cream in the blender. Just pour the cream in, hit the stir button and wait to hear the "chugging" sound. Start with the cream at about 50-60 degrees to make butter. If its too warm, the butter will be very soft and will be more difficult to rinse and knead later on. If too cold, the fat will have difficulty consolidating. You can start with fresh sweet cream or culture your own cream for more flavor.

Commercial culturing is a superficial affair, so don't imagine any brand you have purchased is a model for cultured butter. Industrial butter is cultured in a matter of hours. At home, you can do much better. Unlike factories, you don't need to consider the cost of waiting for cream to ripen. And that's the secret to making extraordinary butter.

Raw cream is naturally full of desirable dairy bacteria and ferments and sours on its own, without the addition of a bacterial culture. Fermentation by lactobacillus bacteria changes the chemistry of cream, making its flavors more complex. Among other changes, it produces lactic acid, making the cream less “sweet.”  Culturing helps make churned cream “break” faster into the two products of butter making: butter and buttermilk.

To culture your pasteurized cream simply add a packet of our buttermilk culture to a quart of cream (adjust proportionately if using more/less). Butter cultures are “Mesophilic,” meaning the bacteria thrive in moderate temperatures. “Thermophilic” yogurt cultures require higher temperatures so are not so effective here.
Pasteurization kills all bacteria, even the beneficial natives. So, if you were to let pasteurized cream just sour naturally, you would be allowing any ambient bacteria that might be lurking, without the natural defenses to control it and the milk would simply "spoil."

Bring the cream to 68-70F (Do not let it fall below 68F or above 78F), add the culture and keep covered and warm for the next 6-12 hours. This will totally depend on how much character you would like to see in your butter. Let your taste buds guide you on this.

After this ripening, the cream should be noticeably thicker and have a well developed aroma (buttermilk culture is often called an Aroma Culture). It should taste delicious, slightly sour, and have no aftertaste. If the cream is bubbly, or smells "off", yeasty or gassy, you have a contamination problem: throw the cream away! The problem was probably caused by one of the following:

After reading through this somewhat lengthy history and process of butter making you might be thinking, "Wow, I think Jim is pushing the "cultured" butter thing!". Yes, Yes, and Yes again .. for the little bit of extra work and the response I get from my friends who really know food, I do prefer the cultured butter.

The Northern countries such as Ireland and Norway have been found to seal their butter in wooden tubs and then bury them in the bogs where it was cool and without air. Some of these are being found even today.

When migrants from Britain and other northern Europeans cooler climates arrived in warmer countries such as America they resorted to keeping butter down a well or in the "spring house" where cold ground water and evaporation kept things cooler.

Today you can simply refrigerate the butter or for larger batches you can freeze all of the butter that exceeds a few days' supply. Freezing butter does it no harm because butterfat crystallizes at about 60F, so taking it from 35F in the refrigerator down to -20 in the freezer does not change its texture. Freezing butter will forestall the absorption of other flavors from the refrigerator and keep the butter flavor much cleaner.

In really hot countries where butter is made in quantity, like India, use clarified butter (ghee), with the last traces of water and milk solids removed to help preservation. Finally clarified butter, or ghee, is butter from which all milk solids have been removed through cooking. The resulting product is clear, rather than opaque, and it can be stored for longer periods of time than butter. Ghee is very popular in India. This can be easily made by gently heating the butter and allowing the solids to settle out while still warm. The clarified butter can then be poured off of the solids. This will also not burn when heated.

A NOTE ON BUTTER AND YOUR HEALTH:

From "Butter through the Ages":

"Scientists now know that, except in rare individuals, dietary cholesterol does not influence blood cholesterol, and fat from ruminants (animals that chew their cud) contains valuable nutrients that maintain health and prevent disease.

It is important to remember that every cell in our body needs fat, and that dietary fat is a cornerstone of good health. Our brain and hormones rely on fat to function, and fat supports our immune system, fights disease, and protects our liver. Fat promotes clear skin and healthy hair, regulates our digestive system, and leaves us feeling sated after a meal. Fat is the body’s preferred fuel, providing us with more than twice the amount of energy as the same quantity of carbohydrates and protein. It helps the body absorb nutrients, calcium, and the fat-soluble vitamins A, D, E, and K.

Fat and protein are found together in nature because it's the fat that helps us digest the protein. So, it makes good sense to eat a well-marbled steak, or a roast chicken with crispy skin. Because fat is digested slowly, eating it leaves us sated and less likely to snack between meals. When you eat a moderate amount of good fat, you'll probably lose weight, but when you replace fat with sugar and carbohydrates, you'll likely gain weight.

Humans have been eating butter and animal fat a lot longer than they have been abstaining from them. Good animal fat, like butter, plays an essential role in maintaining our health, as do quality ingredients and moderate consumption"