Tuesday, January 18, 2011

Questions and Answers About Making Yogurt

Jim Wallace
We are determined to help you!

One of the differences between our business and others is Ricki's dedication to her customers.  She employs a full-time technical advisor (Jim Wallace) to answer your questions about making cheese.  She also publishes a monthly Moosletter with recipes, etc., as well as this blog with articles about every aspect of cheese making.

This is the third in a series of sample questions that folks have written to Jim.  He can always be reached at info@cheesemaking.com to help you with any aspect of making cheese.  Our extensive HELP section is also available with many questions and answers.

General Questions

Q.  I have your Yogotherm from years ago and want to again make yogurt. Unfortunately I misplaced the recipe.  Is there any way I could acquire the yogurt recipe from your site - or elsewhere? 

A. Yogurt is pretty straight forward:  Heat the milk to 185F and hold for 20 minutes (this will release certain milk proteins to make a thicker yogurt).  Then cool to 108-112F and add the culture.  Use the Yogotherm to hold this temperature for 4-6 hrs (or longer if you like more acid).  Remove and immediately chill.  If the yogurt is too acidic, reduce the temperature or time for the next round.

Q.  I have been purchasing Activia because the Bifidus Regularis cultures help keep me regular.  I hate paying so much for an even smaller quantity of yogurt than the regular yogurt (I prefer making my own). If I use this as a starter culture, can I just clone my own yogurt from the Activia to get the same yogurt for less than the store price?  When I was younger I used to do this all the time with Dannon.

A. Your question on re-culturing yogurt is often asked.  With the introduction of more and more probiotic cultures (bifidus), the yogurts have become more complex.  Yes, you could re-culture or add an element from one yogurt to another batch, BUT the problem is that since these cultures rely on a balance, and  it would be very difficult to keep this balance, the final product would be very different and you would have no idea which of the cultures were still active.  For example, I find that our Bulgarian style yogurt is a good one to re-culture because the 2 primary cultures work well together and can remain in balance.  However, adding another culture to that would probably result in it getting squeezed out due to their strongly competitive nature.

Q.  I was looking at your website after reading "Animal, Vegetable, Miracle" and was wondering if you have any information on Greek Yogurt?  I enjoy it and haven't found much information on making it at home. 

A. Greek yogurt is simply a matter of draining the Bulgarian style yogurt to a drier denser state.  Draining through our butter muslin should work for this- just drain until you get the consistency you want.

Q.  I have Ricki's book, and am starting to make cheese.  However, I would like a recipe for Skyr, which is a thick skim milk yogurt from Iceland that is super high in protein.  Iceland has a very long life expectancy, and some say it is due to a combination of Skyr and their Omega 3 rich fish. 

A. The problem with making Skyr is that a particular slime forming yogurt culture is needed.  It seems that no one but the Scandinavians appreciate it so it is hard to find.  Occasionally wild strains of this do creep into some milks but  there are no resources for it that I know of here.

Q.  How can get my yogurt sweet?  I have a friend who likes it sweet and she can hardly eat now- only soft food like baby food. 

A.  We sell a sweet yogurt on our website.  The longer you let it set, the thicker it becomes and the more acidic.
About the Bacteria in the Cultures

Q.  I have friends who won't eat the yogurt I've been making with your cultures because they noticed the yeast ingredient - can you speak about the use of yeast here? 

A.  Yeast hulls (dead yeast) are a component in our culture since they provide the necessary nutrients for the yeast as we try to re-hydrate them to a healthy state for the job of cheese making.

Q.  I am interested in buying the Lactobacillus delbrueckii subsp. bulgaricus culture. You seem to have the following:
1.    Yogurt Bulgarian - Contains live cultures s.thermophilus, l.bulgaricus, skim milk and/or lactose, lactic cultures, ascorbic acid.
2.    Yogurt (DS) tangy - Culture contains: s.thermophilus, l. delbrueckii, s.bulgaricus, s.lactis, dry milk powder, lactose, malto dextrin and autolyzed yeast.
3.    Yogurt (DS) sweet - Culture contains: Lactobacillus acidophilus, Bifidobacterium species, Steptococcus thermophilus, Lactobacillus delbrueckii subsp, non-fat dry milk, lactose, malto dextrin and autolyzed yeast

The first refers clearly I think to subsp bulgaricus and the second has both subsp bulgaricus and subsp lactis. Does the third have subsp delbrueckii and is that why you haven't added any subsp to it or it is a mistake and should be bulgaricus as well? 

A.  All of the highlighted names refer to the culture you are interested in but none as single strains.  They are all existing as part of a complex culture.

About Using Goat's Milk

Q.  Is the yogurt culture the same for cow milk and goat milk?

A. Any of the cultures can be used for any milk.  Goat's milk, by nature, will be thinner in texture.

Q.  I'm making goat yogurt and my first try didn't thicken at all. I read online that goat milk won't thicken very much, so that made me feel better.  I've never had a problem making yogurt with cow's milk.  Do you recommend any of your yogurt cultures for goat milk especially? 

A.  Make sure you heat the milk to 185F and hold it there for 20 minutes.  Without this, you will be losing the whey proteins that are so important for yogurt body.  Goat's milk does tend to make a thinner bodied yogurt than cow's milk.

Q.  I received your yogurt culture and immediately put it in the freezer.  I used 2 quarts of goats milk and 2 of your packets of culture.  I followed the directions very carefully.  I heated the milk to 180F for 1-2 minutes, then I cooled the milk to 116F as per the directions on the packet.  I mixed the culture with some cooled milk (116F) thoroughly and mixed this with the rest of the milk thoroughly.  I put it in the yogurt maker and waited 6, 12, and 24 hours.  Nothing happened- the milk was the same as when I put in your culture.  I am using the right equipment, using fresh milk, following directions very carefully, and I am totally baffled as to why the yogurt is not making.  Could it be a culture problem, or do you have other ideas or suggestions? 

A.  At the end of your yogurt session does the milk taste at all acidic to you?  Is there a yogurt-like flavor?  If so, the culture is doing its job converting lactose to lactic acid.  If it is not thickening after raising to 180F,  then next time hold at that temperature for 20-30 min before cooling.  If there is no acid or flavor after ripening, then something has happened to the culture.  If your thermometer is off then perhaps you added the culture too warm.

This could also be a problem of over processed milk, not UP but heated well over the 161F that is normal for pasteurization.  Since I use these same cultures myself, I do not think there is a problem with the culture itself.

Q.  My child is allergic to cow's milk.  I saw the yogurt starter has dry milk powder in it.  Is there any starter that doesn't have dry milk powder in it?
A.  All of our yogurt cultures contain dry milk powder but the amount going into milk would be miniscule, probably less than .01%.  This is usually consumed by the bacteria, since it is there for fuel to get them started from the dry state.  If you are concerned about the small amount of milk powder, the solution would be to make the Bulgarian yogurt (Y1) with goat's milk for 1-2 generations using each batch to culture the next and using this to make the batch for your child.  The final amount of dry milk powder from cows will be almost gone.  The other yogurts are too complex to re-culture and stay true to strain balance.


the-cooks-corner-blog.com said...

You recommend holding the milk at 185 degrees for 20 minutes. How accurate does that have to be and what is the best way do it?

Jeri said...

Thanks for your question. We prefer that all technical questions go to Jim Wallace, our technical advisor at jim@cheesemaking.com. Otherwise, we would all be fielding questions to the best of our limited ability when we have a real expert on our staff!

DASKMA said...

HI...I've been making and enjoying yogurt for a while but encountered a new puzzle I hope you can help me with. Yesterday I made a batch of yoghurt in the microwave (unheated, but wrapped in a towel to set) and after 9 hours opened it and it still had not set. So I left it in the microwave overnight. This AM it had thickened and I put it in the fridge. But now I am concerned about its safety. It was out (wrapped and setting in the closed microwave) from about 11AM yesterday until about 8:30 AM today....with one opening check last night. Is it safe to eat? Or should it be thrown out? Thanks in advance...

Jeri said...

I'm sure it's fine, but you will get more of an explanation if you write to Jim Wallace, our technical advisor at jim@cheesemaking.com.
Happy cheesemaking!

helicoptermom said...

Hi. Can you make homemade mozzarella with cultured buttermilk? Will it produce a better product?

helicoptermom said...

In making homemade mozzarella, can I use cultured buttermilk? Will it create a better product?

Jeri said...

We funnel all our technical questions to Jim Wallace at jim@cheesemaking.com. He knows all! (He also prefers to get his e-mails direct, so the best thing would be for you to contact him with your interesting question.

Locked and Loaded said...

Is there a different temp used when using raw milk?

Jeri said...

No. It's the same no matter what milk you use.

Sofia Grogan said...

I'm making yogurt for the first time using a yogurt maker. I'm using raw milk and I noticed little curdles in the milk as I was warming it on the stove. In pictures, it looks like the consistency is more creamy while heating. Is this a sign my yogurt won't turn out right in a few hours?

Anonymous said...

I left my yogurt jars in a water bath in my crock pot on warm by accident overnight and found the temperature was up to almost 160 degrees when I woke. The "yogurt" looks firm but should I throw it out?

Anonymous said...

I have been using the same re-culture (started with Dannon) for yrs., and I make approx. a gallon per month. And it is still making what I think is yogurt. Is it? If it tastes the same and has the same consistency, isn't it the same?