Yogurt from store-bought starter

Each spring and summer our homestead produces a bounty of fresh goat's milk from our small backyard herd of Saanen cross goats. While we make many things with the milk - from custard to soft cheese chèvre and even goat's milk soap - my family's favorite is yogurt. There are many methods of making yogurt, often using specialty cultures bought from cheesemaking supplies and specialized yogurt incubators. To avoid having to buy & ship cultures and owning another piece of equipment, I found a fool-proof way of making yogurt with off-the-shelf yogurt and my oven. We now enjoy fresh yogurt whenever we like!

My doe Gazelle with her Saanen x Nubian twins.

Yogurt is a fermented milk product that provides digested lactose and specific viable bacterial strains, typically Streptococcus thermophilus and Lactobacillus bulgaricus. It is a source of several essential nutrients, including protein, calcium, potassium and vitamins B2 and B12. With the domestication of milk-producing animals like cows, sheep and goats, as well as horses, buffalo and yaks, milk products became a part of the human diet. It is generally thought yogurt, and other fermented milk products, were discovered by accident as a result of milk being stored by primitive methods in warm climates. Milk spoils easily, making it difficult to use. Herdsmen in the Middle East discovered that milk carried around in bags make from intestinal gut would cause the milk to curdle and sour - the rennet from the intestinal juices would preserve and help conserve the otherwise easy to spoil milk for extended periods of time. For millennia, making yogurt was the only known safe method for preserving milk, other than drying it in the form of cheese. The Greeks were the first to write about yogurt at around 100BC, mentioning the use of it by barbarous nations. Genghis Khan reputedly fed his army yogurt - already a staple of the Mongolian diet - because he thought it instilled bravery in his warriors! It is generally thought the word 'yogurt' comes from the Turkish word 'yoğurmak,' which means to thicken or curdle.

The first industrialized production of yogurt started in 1919 in Barcelona by Isaac Carasso – he named the company 'Danone,' or 'Little Daniel,' for his son. While Turkish immigrants had brought yogurt to North America in the 1700s, it did not really catch on until the 1940s. That is when Daniel Carasso, the son of Danone founder Isaac, and Juan Metzger took over a small yogurt factory in the Bronx, New York, renamed it Dannon and quickly introduced yogurt with fruit on the bottom in 1947. The popularity of yogurt soared in the 50s and 60s with the boom of the health food culture and is now readily available in many varieties, including sheep and goat's milk yogurt. The types of yogurt typically available today are influenced by local traditions and lifestyles. For instance, Eastern European and Asian cultures have the milk undergo an alcoholic fermentation to make kefir and koumis. In Spain and Germany, yogurt is typically heat-treated to kill the bacteria, and in the United States as well as other countries, various probiotics and/or prebiotics are added to the mix.

It has been my experience that certain off-the-shelf yogurts work much different than others - they all make yogurt but some of the textures were not what I would call pleasing. From all the different yogurt brands I’ve played with, Stonyfield Organic is the most consistent. It is important to make sure the jars are sterile to avoid contamination with unwanted bacteria and yeasts, and to start with a healthy starter to promote vigorous fermentation of the right cultures. Especially households that make other ferments like vinegar, bread and kefir do well to pay close attention to cleanliness. But once you've got your ducks in a row, the actual process of making yogurt is pretty simple and takes less effort than you might expect!

Yogurt starter, milk and heat – all the essentials for wholesome homemade yogurt!

What you'll need:

- one gallon organic whole milk (I use raw backyard goat milk)

- 1 to 2 cups of Stonyfield Organic Yogurt (I use low fat as I am cow dairy sensitive)

- stainless steel pot or a Dutch oven

- thermometer

- stainless steel wisk

- wide mouth (canning) funnel

- five mason jars with lids

 

How to sterilize?

There are several methods of sterilizing equipment: anyone who has canned before should be all set. Anything that is in contact with the milk after it is pasteurized should be sterilized; this includes the funnel, the mason jars and the lids.

As I brew as well, I sterilized my mason jars using the brewing sanitizer Star-San and stored the jars on my dishwasher drawer - this is quick and energy efficient.

Method one: run the jars and lids through the hot / canning setting of your dishwasher.

Method two: boil the jars and lids in your water-bath canner for 10 minutes (just like prepping jars for canning).

Method three: use a brewing sanitizer like Star-San, or iodine.

Method four: soak in a sterilizing bleach bath, and rinse very well afterwards.

Step by Step on making yogurt:

- Heat your milk to 182°F (this pasteurizes the milk).

- Let it sit for 10 minutes on low at around 182°F.

- Fill your sink with cold water (add some ice packs if you have them). Put the pan with hot milk in the cold water to cool the milk down to 110-120°F.

- Scoop 2 cups of Stonyfield yogurt into the lukewarm milk. If the yogurt is straight from the fridge, add at 120°F; if it is room temperature, add at around 110-115°F. You want the cultured milk to be at around 110°F.

- Gently whisk the yogurt culture into the milk. If you like, you can dilute it separately in some of your milk so it is less chunky and dissolves easier but this is not necessary.

- Pour the cultured milk into mason jars (use wide mouth funnel) and close the lid.

- Put the mason jars with cultured milk into the oven – leave the pilot or the general light on.

- Leave overnight, the next morning your yogurt is ready for consumption (after that, refrigerate).

Some beautiful fermentation is visible at the rim of the fresh yogurt.

The trick to culturing yogurt is to use a (turned off) kitchen oven as an incubator – it is well insulated and every house has one. If you have an old-fashioned gas stove which lights with a pilot light, that is all it needs to stay all nice and cozy inside. If your oven does not have a pilot light, it should have a regular light bulb to see what is going on inside. Leave that on (with the door closed), and it will keep the oven just as comfortable – a perfect environment for culturing yogurt.

Tip: if you strain your yogurt through some cheesecloth until it is as thick as you like, you just made your very own thicker Greek-style yogurt.

Reference:

https://academic.oup.com/nutritionreviews/article/73/suppl_1/4/1819293