Sunday, January 16, 2011

Homemade Yougurt with Lactose-free Milk

A question I get a lot from visitors to my homemade yogurt website is: "Can I make homemade yogurt from lactose-free milk?". Strictly speaking, the answer is no… but yes.

Let me explain. Lactose is the sugar in all milk from mammals. Coconut, soy, almond and rice milk are not really milk, do not contain lactose, and will be the subject of a future blog post. So individuals who are lactose-intolerant typically cannot enjoy milk, and the reason is that they lack the enzyme lactase. Lactase breaks the lactose down into two simple sugars: glucose and galactose, which can easily be consumed by anyone who can ingest sugar.

It is worth noting that most of the world's population (as much as 70% by some estimates) lacks this enzyme after about the age of three or four. This is nature's way of weaning us off of our mother's milk. But variety is the spice of life, and some humans never lost the ability produce lactase. Primarily of Middle Eastern and European decent, these people went on to domesticate mammals and drink their milk. Other groups of people, like Native Americans, are almost exclusively lactose-intolerant, and therefore never domesticated mammals for their milk. So as a "disorder" it would be more accurate to say that a minority of people are "lactose-tolerant", since intolerance is the usual condition. But I digress…

So brands of milk like Lactaid have come on the market, specifically to address this issue of lactose-intolerance. If you look at the ingredient labels of regular cow milk, and a lactose-free brand, you will see that the sugar content is the same. Why would this be if the lactose was removed? Well, it is because Lactaid has lactose in it when it goes into the container. But it also has lactaid, the enzyme needed to break the lactose down into glucose and galactose. So it is true that the milk no longer has lactose when it gets to you — which is why they can market it that way — but it accomplishes this by converting it to two other sugars. The bacteria cultures in yogurt would do this anyway, so it actually saves them a step. This is why you can indeed make homemade yogurt from lactose-free milk, but not because there is no lactose in it. Rather, because lactase has been added for you.

It is worth noting that there is not much lactose left in yogurt even when you use regular old milk. As a result, many lactose-intolerant individuals can enjoy it. You might want to try a small amount of good quality plain yogurt, and if all goes well, start making your own. If that fails, use Lactaid or other lactose-free brand.

23 comments:

  1. I just wanted to be the first person to thank you for this blog post. I found you simply by doing a google search for making your own yogurt and while I love your actual site, I also really appreciate you doing this post on the Lactose free milk. I am lactose intolerant because of medications, and even regular yogurt upsets my stomach. I have wanted to make my own yogurt but wondered how the lactose free milk would work! Thank you so much for posting this!

    I haven't read any other posts on your blog yet so if you have already addressed this, sorry. But I was curious if it is possible to make yogurt that is flavored (like vanilla). Would you add the flavor after or before you heat the milk?

    Thanks again!

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  2. Sheena,

    Thanks for the kind words. You flavor the yogurt after it is completely finished incubating and has chilled overnight. You can use vanilla, honey, jellies, jams, and anything else that can be mixed in yogurt. Putting it in before the yogurt is done, however will cause issues with incubation.

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  3. anybody else having severe gastric discomfort after eating 2-3 day old homemade yogurt? The yogurt has lost its smooth creaminess and looks a bit more "particulate" - it's hard to describe..maybe on its way to curdling?

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  4. I forgot to say that I drink lactose free milk but made this in my new yogurt maker with Organic Valley 1%. This has happened twice and I am hesitant to eat more.

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  5. Hannah,

    I have not had this experience, but I don't use a yogurt maker, nor have any issues with lactose. For how long did you incubate the yogurt? And did you heat the milk to 185 F first?

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  6. I followed direction which said tobring milk to a boil, til it started climbing the walls of the pan, hold it ther for 1-2 mins, then cool down to 110 and proceed normally. this last time i incubated it for 12 hours to get a thicker creamier yogurt-which is was for 2 days , then changed texture and i got a stomach ache .i guess that i will have to chance it again and skarf some down. will let you know what happens.

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  7. I just really want to say thank you for this. I have tried and tried to eat regular yogurt without success. I did make my own from Lactaid milk and it's fantastic. I used Stonyfields Oikos Greek yogurt as the starter...Thanks again.

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  8. I thoroughly enjoyed the video(s) on yogurt making and this blog on lactose intolerance. I never knew the mechanism of lactose intolerance nor how Lactade milk addressed the issue. I am in the Philippines and it is almost impossible to get non-UHT processed milk. Must I do anything differently to use UHT milk?

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  9. I guess I am not understanding the whole lactose thing , I know I have it when I eat to much ice cream or such.
    My question is does Greek Yogurt have latcose?

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  10. Majeral,

    Yes, it has lactose. But less so than milk or cheese.

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  11. Thank you for this blog. I just bought a yogurt maker because I'm getting tired of paying through the nose for my favorite brand. I like being able to actually pronounce the ingredients in my foods! LOL That being said. I'm lactose intolerant but can eat yogurt about every other day without problems. To be able to make my own with Lactose free milk is a dream come true. Yogurt with granola & fruit is my breakfast of choice.

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  12. I started making my own yogurt a few months ago using a good quality Greek-style yogurt as a starter. I have never been a milk drinker so I fluffed off symptoms of an intolerance to a food item as a reaction to an especially vicious seasonal allergy year. The symptoms remain so I can only assume they may be coming from the yogurt, the only really new addition to my eating habits. Thank you for explaining about being able to use lactose free milk. I am going to experiment using the milk and lactose free Greek yogurt to see if I can come up with something I can eat.

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  13. great post, just wanted to mention that it is strongly possible that (the need for) domestication (e.g, in habitat conditions where we need to make use of calories that ruminants can provide us...the extent to which those conditions are also anthropogenic is yet another discussion) ended up creating selective pressure strongly favoring people who retained the ability to produce lactase. In other words, husbandry over time causes lactose-tolerance in a population.

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  14. PS i am lactose intolerant, and make and eat homemade yogurt all the time. i ferment it heavily so it is very sour. it keeps better and ensures that as much as the lactose has been converted to lactic acid as possible.

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  15. ayoungethan,

    Good points. I think it is better to say it how you did initially though, that domestication created "pressure strongly favoring people who retained the ability to produce lactase". Meaning, due to genetic variation, there were already people who had the ability, and their environment (one of agriculture) created positive selection for that trait. That is not the same as saying "husbandry over time causes lactose-tolerance". So long as the intolerant group can survive and reproduce themselves, their genes pass on intact. Which is why the population of India continues to be almost exclusively lactose intolerant, despite widespread husbandry in their country.

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  16. I find that Lactase Yogurt tastes different than regular yogurt. I have been making yogurt for years since my parents taught me. I have to say it lacks the acidity of regular yogurt. I am not sure why. If it's not a bit sour it's not yogurt to me. has anyone else had this experience?

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    1. I make Lactaid yogurt for my elderly mother all the time, and yes, it never gets as tart as "regular" yogurt. But then Lactaid milk tastes quite sweet to me to begin with so maybe that is why. I incubate it for at least 12 hours, and because I find that it never sets up very firm I strain it after it cools to remove some of the whey and give it a creamier texture.

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    2. Raymond, I make a gallon of Lactose free yogurt a week, using much cheaper walmart's version. I've found adding 2 teaspoons of unflavored gelatin as the milk begins to heat will thicken and set up as the yogurt cools in the refrigerator. Also, google: "24 hour yogurt" lots of resources out there on this, past 4 batches, I've done this using my Excalibur Dehydrator (trays removed), 120 deg for first hour, 85 deg remaining hours), so maintaining this incubation period is easy for me. Results: creamy, thick, almost whey-free yogurt requiring no straining, yes sweeter than commercial yogurt. Best: no digestive upsets, including the 'explosive' diarrhea (sorry for the graphic) that always followed eating commercial yogurt. Once a month I replace my starter with 1/2 cup of Fage Greek Style Yogurt (available in 7 oz snack size), otherwise I keep out 1/2 cup of my homemade yogurt to add as starter for my next batch.

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    3. ssandee51: I think if you try 110 F for 8 hours in your excalibur, you will find that you do not need the gelatin (after heating the milk to 185 F first). You are incubating at 85 F, which is well below the active range the for cultures you are using. The two primary cultures in Fage are Streptococcus thermophilus and Lactobacillus bulgaricus. When used together, they have an optimal range of 109 - 111 F degrees. Anything much below 96 F and they don't reproduce at all. Which would likely explain why you are not getting any whey at all and that it is sweet. If you enjoy it, by all means keep up the good work. But I doubt what you are making has much in the way of active cultures in it, and is likely gelatinized milk.

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    4. If you make 24 hour yogurt, all the lactose is eaten up by the probiotics. No need to use lactose free milk. Plenty of techniques on the Internet to keep the fermentation temperature at the optimal level.

      I strain the yogurt anyway, even though it is amazingly rich and creamy after the 24 hour fermentation. I use the now lactose free whey to make a lactose free high protein ricotta...

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    5. Jake, I think your tartness preference is probably a bit higher than most people's. After 24 hours of incubation you produce a lot of lactic acid, which many people (myself included) would find off-putting. If you start with lactose-free milk, on the other hand, you can stop incubation whenever you reach the tartness/thickness preference you like.

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  17. I'd love to see some general recipes/amounts, temps, times to ferment, etc. for the lactose free milk homemade yogurts. I have a friend who was horribly ill after eating Yoplait Lactose free yogurt. So I promised to find her an option.

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    1. Kate,

      This blog is a companion to my yogurt making website. Use the instructions there, only with lactose-free milk, and you will be all set:

      http://www.makeyourownyogurt.com/

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