How long does fresh yogurt last?

Yogurt can be kept in a refrigerator under 40F for up to two weeks.

Can yogurt be frozen?

Yes, yogurt can be frozen for up to 3 months.

Organic, whole cow's milk, grass-fed if possible. You can also use raw cow's milk, goat's milk or sheep's milk.

Look for mold or curdling, signs that yogurt is not healthy to eat.

How to make homemade Yogurt from scratch- an easy step by step guide with no special equipment needed! 1 quart milk yields 2 cups strained yogurt.

1 quart milk – whole milk, raw milk, goats milk, or sheeps milk
1 tablespoon plain yogurt with active live cultures (or yogurt from a previous batch)
Cheesecloth
Strainer
Thermometer
Optional: 1/2 cup milk powder, see notes!

Turn oven on lowest setting for 10 minutes. Turn off, but leave light on.
Heat milk gently in a saucepan or dutchoven on the stove over medium heat to 180 F, stirring often. If you want all the benefits of raw milk yogurt, remember to heat the milk only to 110 degrees and no higher. This ensures that milk’s own bacteria will stay alive. Or if unsure, heat to 180F .(please see notes)
Let the yogurt cool to 110-115 F.
Add 1 tablespoon of yogurt. ( The general rule is 1 tablespoons yogurt per quart of milk -resist the temptation to add more, or you will end up with yogurt that is watery and overly sour. I find that 1 tablespoon is best! )
Place in a clean jar, cover, wrap in a towel, and place in the oven with the light on, (100-110F). The light will act as an incubator. Alternatively, you could also pour this into an instant pot (yogurt function), slow cooker, in a cooler with hot water bottles. The idea is to keep yogurt at a steady but low warmth (100F-110F) for 6-8 hours. If it gets too warm, it can curdle.
After 6-8 hours, strain with a cheesecloth over a strainer over a bowl. (Straining is optional, this thickens the yogurt). Save the whey for Beet Kvass, smoothies, soups, or water your plants with it!
Scoop into a clean container, whisk until smooth, cover and store in the fridge for up to 2 weeks. Make another batch before you run out!

If you like sweetened yogurt mix in honey, vanilla, maple, or agave. I prefer to sweeten yogurt in smaller batches, keeping my main batch, plain.
Making yogurt from unpasteurized raw fresh milk is full of nutritious enzymes, fat-soluble vitamins and linoleic acid. If you want all the benefits of raw milk yogurt, heat the milk only to 110 degrees- which will keep these enzymes alive. If you are nervous about the process, or this is your first time making yogurt, just heat it to 180F. You will feel more confident about the whole process and when you get more comfortable, you can try this with the lower heat.
Adding milk powder to the heating milk thickens yogurt without straining it. Add 1/2 cup to give it a thick Greek Yogurt-like consistency. FYI: You can also use goat’s milk powder.