Trying to make yogurt with an Instant Pot

                Apparently there is always more to learn about yogurt. I was recently gifted an exciting kitchen gadget—an instant pot with a yogurt setting! I was so excited to try it, and on that weekend I made a batch of yogurt. Because I had always depended on a thermometer to make yogurt, I tested the temperature of the milk and yogurt throughout the process. After heating the milk, the temperature was only 165⁰ F. I tried to rerun that setting, but it would not heat much further, so I used the regular slow cook function to get the milk to 180⁰ F. Then, I cooled the milk as I usually do, added the starter, and set the machine to the fermenting setting for 14 hours. As soon as it beeped to let me know it was finished, I checked the temperature, and it was below 100⁰ F. The texture was much thinner than I get when the yogurt ferments at 155⁰ F. The yogurt still tasted good, but it was not quite the texture I was hoping for. 

                I contacted the Instant Pot customer support, and their answers were not particularly helpful. I am still unclear if they intended the Instant Pot to ferment yogurt at below 100⁰ F or if the pot does not work as it is supposed to. At one point they offered to send me a new heating element, but I want to see if I can get it to work well enough with the one I have first. I am going to try to ferment it for 18 hours to see if fermenting it for longer can make up for the lower temperature and still result in a thick yogurt.

Instant Pot yogurt

Lots of Yogurt

                Because my small batch of yogurt was fairly successful, I was ready to try a larger run. I bought a gallon of 1% milk from my favorite National Wholesale Liquidators that sells milk for $3.00 usually. I had in the fridge Stop and Shop brand low fat yogurt that contained live and active bacterial cultures. And I was ready!

                This time, I heated my milk up in a crockpot. It took close to 4 hours for the milk to reach 185⁰F. Then, somewhat foolishly, I attempted to cool the milk by immersing it into a sink filled with cold water. Big mistake! Immediately, the crock developed a hairline crack. I quickly, (with the help of SP,) transferred the milk into 2 cooking dishes, and then let them cool on their own. Unfortunately, I let them cool to lower than 115⁰F, so I put them into the oven to warm them back to that temperature. In the meantime, I put about ½ cup of the yogurt to be used as the starter into a bowl. As soon as the milk was 115⁰F, I mixed about 1 cup milk into the yogurt, and then poured half the starter into each of the 2 cooking dished. I covered the dishes, then draped them with a blanket, and put 2 pots of boiling water on top to help maintain the warm temperature. I let the yogurt incubate for 8 hours. Then, I strained the yogurt for about 2 hours.

                I was intrigued that the yogurt from each of the dishes came out different than each other. The one in the shallow pan incubated at a lower temperature (likely due to the increased surface area it had to let heat escape.) That yogurt was a bit thinner, maybe a tad thinner than typical yogurt, but still definitely a yogurt consistency. The other one was much thicker, closer to Greek yogurt consistency. And both of the yogurts tasted like…yogurt! It was not too tart. It just tasted like plain yogurt. And none of the slightly grainy texture I had in my first one. It made about 4 quarts of yogurt, which means that it costed about $0.75 to make 1 quart of yogurt. I was pleased.  

Now, I have to find another method of heating my milk. I might get a large pot to be used for just this purpose. 

thicker yogurt before straining

thinner yogurt before straining

the yogurts straining!

thick yogurt after straining...it looks like yogurt, right?

My Yogurt Adventure

                I did it! I successfully prepared homemade yogurt. (See my post from last wee about my yogurt plan.) Props to my parents for allowing this adventure to happen in their home with their milk. They did not have yogurt to use as a starter, so shout out to YT and family for sharing with me a spoonful of Stonyfield Organic plain yogurt.

                This is what I did:

1. Find a thermometer. I had one, and then discovered that the battery was dead. Replaced the battery.
2. Pour 12oz Pride of the Farm lowfat milk into top of double boiler.
   
3. Heat milk to 180⁰F. Keep checking temperature with thermometer until it is just right.
4. Keep milk on lowest flame to maintain the milk at that temperature for about 5 minutes.
5. Remove from heat and let set milk pot in ice bath until temperature is 115⁰F. Keep checking temperature with thermometer until it is just right.
   
6. Add a bit of the milk to the spoonful of yogurt that is in a bowl at room temperature.
   
   
7. Transfer warm milk to insulated hot cup.
   
8. Pour the milk-yogurt starter mixture in.
9. Seal cup and put it in hot water bath. The water was about 125⁰F.
   
10. Wrap in towels to keep it insulated. 
    
11. Over the next 3 hours, I checked the temperature of the water bath twice and added more hot water to bring the temperature back up to 125⁰F. After that, I just let it sit undisturbed overnight.
12. After a total of 16 hours, I opened up the incubated milk.
    
13. I secured a thin rag over the top of a container and strained the yogurt through it for about 1 hour. I was left with some whey in the container. 
    

                I would definitely call this a success! The flavor was not too tart as I feared it would be after reading so much ahead of time. It did not taste like any yogurt I had eaten before, but it definitely tasted like yogurt! There was a slightly grainy texture to it, which from my reading may have to do with heating the milk too rapidly or moving the yogurt too much while it incubates. I will try to heat it slower next time and then leave it to peacefully incubate.

                 Anyone else want to try this? 

My Yogurt Plan

I have been reading up on yogurt. That is, making yogurt at home. I enjoy yogurt as part of my breakfast every day, and I was wondering if there was a cheaper way to have yogurt. I saw an advertisement for a yogurt maker, and a whole new world that I never knew existed was opened to me! My first though was to purchase a yogurt maker. Many different companies make them, and they are at a few different price points. Then, as my research progressed, I discovered that yogurt makers do not actually make your yogurt for you. Most of them are merely a warming device. They maintain the yogurt at a constant temperature to promote the growth of the bacteria that have been added to the previously heated milk. My further reading led me to discover that there are other methods of incubating yogurt that do not involve a special device. And besides, where would I store it??

Disclaimer: I have not made yogurt yet. It is on my agenda though. Perhaps it will work. Perhaps it will require some tweaking before I get it right. This is my plan: I will use my second, not yet used, crockpot to incubate my yogurt. I might have to try it a few times until I can get the temperature settings correct. But I am getting ahead of myself. Do you want to know how it is done? Well, I will tell you.

1. Heat 2 quarts milk to 180⁰ F and maintain milk at this temperature for about 5 minutes (I plan to use a thermometer)
2. Cool milk to 110-115⁰ F (again, I’ll need the thermometer)
3. Pour about 1 cup of milk into a bowl that has a few tablespoons of yogurt that contain live active cultures, and gently mix
4. Pour yogurt-milk mixture back into milk
5. Incubate milk at 110-115 ⁰ F for 8-24 hours (I think this might be the hardest part) Once this time is up, the milk should have thickened into yogurt
6. Now put in in the fridge to cool
7. Eat!! (the best part hopefully)

From my extensive reading, there are some issues that can come up. Sometimes, the milk does not thicken into yogurt. This can happen if the yogurt with the bacteria is added before the milk cools to 110-115⁰ F, because the bacteria will be killed from heat at higher temperatures. It can also remain liquidy if the yogurt cools below temperature while incubating, because the bacteria need that warm temperature to multiply. It also seems that homemade yogurt is typically thinner than the store bought varieties, as sometimes companies add thickeners. This can be remedied by straining the yogurt through a cheese cloth or stirring in powdered milk to the milk while heating.

So this is my proposal to myself: Brendel, make some yogurt! It might take some experimenting until I get good yogurt. I will keep you updated. Also, I still owe you my margarine-less sugar cookie recipe…I haven’t forgotten!

If any of you have made yogurt before, please let me know your experiences and any tips you have.

What is the Point of Pasteurizing?

                The goal of pasteurizing is to reduce the amount of bacteria in food and make diseases caused by those bacteria less likely. There are a few types of pasteurization, and the main differences between them are the temperature and the length of time needed to complete the process. The higher the temperature, the shorter the time needed for the food to be at that temperature to kill sufficient bacteria. Pasteurization also extends the shelf-life of foods because there is less bacteria to grow and cause the food to spoil.

One of the most common foods that are pasteurized is milk. Unpasteurized milk, more commonly called raw milk, has recently been in the headlines. While some promote supposed health benefits of raw milk, the medical community warns people not to drink it due to the risk of contracting diseases from bacteria in it. While there are some vitamins that can be degraded by heat and pasteurization, these are not the vitamins that are found in large quantities in milk to begin with.

As an aside, there are some vitamins in fruits and vegetables that are degraded from heat, and therefore are found in fewer quantities in cooked fruits and vegetables. Don’t worry though! There are still plenty vitamins and minerals in produce. Go ahead, eat fruits and vegetables raw, cooked, grilled, steamed, or however you like them. As long as you are having a variety of fruits and vegetables, it is quite unlikely you will develop a deficiency by cooking your produce.

Let me know if you have questions about specific foods that are pasteurized.