I found an article that compares white bread made with yogurt whey to the same formula made with a sourdough starter.
Valorization of Acid Whey to Produce Sourdough Bread Starter
Contrary to what the title might make you expect they aren't making a sourdough starter, they are making bread.
I had to look up "valorization".
Valorization is the process of increasing, enhancing, or realizing the economic, social, or functional value of something, such as turning waste into products, upgrading commodities, or maximizing the societal impact of research. It involves transforming low-value materials into higher-value resources (waste valorization) or validating the worth of ideas and knowledge.
Their primary interest is reducing waste.
Abstract
Acid whey, a by-product of Greek yogurt and acid-coagulated cheese, poses environmental challenges due to high biochemical and chemical oxygen demand. It also contains lactic acid bacteria (LAB) with the potential to enhance fermentation. Using acid whey in breadmaking addresses waste management while creating value-added products. To evaluate acid whey as a starter in bread production and compare its performance with commercial sourdough and white bread. Acid whey from skim milk yogurt was used to replace 50% of the water in the dough. Three breads were prepared: white bread (WB), acid whey bread (AWB), and commercial sourdough bread (CSB). Physical, chemical, microbial, and textural properties were measured. Consumer acceptability was assessed using a nine-point hedonic scale with 81 participants. Data were analyzed using ANOVA and paired t-tests (p < 0.05). AWB showed greater loaf volume (1550 ± 20.4 cm3) than WB (1375 ± 20.4 cm3, p < 0.05) and similar aeration to CSB (p = 0.97). Its pH (5.17 ± 0.03) was lower than WB (6.07 ± 0.12, p < 0.05), indicating stronger fermentation. AWB displayed lighter crust color and delayed mold growth compared to WB. Sensory tests showed higher scores for AWB in flavor, aroma, color, texture, and overall acceptability (p < 0.001). Notably, 76.5% of participants preferred AWB over CSB for purchase. Acid whey is a viable alternative to commercial sourdough starters, producing bread with favorable qualities while reducing dairy industry waste, offering benefits for sustainable food production.
I question many of their choices but this work could make a good starting point for playing with yogurt whey as a souring agent.
Gary
You deserve the Medal of Valorization for posting this, Gary! :)
I regularly use the whey from my homemade yogurt, especially for white breads. My yogurt ferments for 16-17 hours so it is more acidic than most storebought varieties. I too question some of their choices, especially this one:
Skim milk yogurt? Yuk. And 50% of water is a huge amount. That's double what I've arrived at as a max amount to use.
Have you observed the pH of the dough dropping over time with the added whey? I'm wondering if the LAB in yogurt will process what they find in dough.
I agree with your yuk. I guess they chose skim to avoid the added fat confusing the comparison.
I think they would have done better to add a bit of yeast to the sourdough to match the acidity of the whey bread.
Gary
I haven't measured the PH so can't answer that one.
I did not like the taste of breads made with 50% whey. Apparently yogurt LABs are different than sourdough ones.
One of my fave white breads uses ~20% (of H2O) whey and 15% (of H2O) CLAS. Ferment time and temp are critical.
Two organisms commonly used in yogurt are Streptococcus thermophilus, and Lactobacillus delbrueckii subspecies bulgaricus. Both have optimum fermentation temperatures above human body temperatures, whereas sourdough is typically fermented at lower temperatures. I can't help more than that, I'm allergic to the whey fraction of milk so avoid it as much as I can.
You can also get pure lactic acid at homebrew shops.
It so happens that the CBK-110 breadmaker they used raises and proofs in two cycles, 88º and 95º. Those temps favor the whey loaf, and puts the sourdough loaf at a disadvantage.
And then they bake it for 90 minutes (!) at the darkest crust setting. The baking temp would have to be VERY low (well below 300º) for such a small loaf to survive such a long bake.
Speaking of bread machines, the latest models of Panasonic BM's have a "sourdough starter" recipe that uses yogurt, rye flour, water, and a pinch of yeast, fermented at 82º for 24 hours. I tried it when I first got the machine and found the bread it made awful.
I’m an advocate for using whey in breads. I typically use a heat-treated whey as a replacement for up to 100% water in Hamelman’s 5-grain Levain, and have for many years. I have used it occasionally in other breads as well.
Let me explain heat-treated. I make my own yogurt in a large 3-liter batch. I take about half of this and place it in a a cold oven which is then turned on. After 20 min. or so I remove and cool it, then drain it through a flour sack towel overnight. The heat will slightly coagulate the yogurt, and the drained portion is what I call whey. The drained yogurt is my spreadable replacement for cream cheese.
I have never measured the pH of the whey, but I don’t believe it is terribly acidic because it will get moldy if it is left refrigerated too long. The acidity of the 5-grain Levain is predominantly from the 125% hydration levain in the formula. I’ve made it with both water and whey and found no difference in the dough behavior. Maybe the heat kills off the yogurt LABs.
-Brad
I was wondering how the whey dough actually rose; did the yoghurt whey have magical leavening properties? - until I read the relevant section of the paper "Fleischmann's Quick Rise Instant Yeast (Canada) contained sorbitan monostearate, and ascorbic acid was used as the added yeast."
Lance
I make my yogurt as well. 3 qts at a time. I dislike Greek yogurt . So I never strain it but the yogurt cheese heat treatment is interesting. Thank you. c
I also don’t like Greek yogurt - bland and tasteless to me.
I never measure the temperature of the yogurt. I use a pyrex glass pot (it was my grandmothers and is easily 50 years old) with a lid and put it into a cold oven, then turn it on convection at 350*F but I doubt the oven gets to temperature that fast. In about 20 minutes I can see several cracks forming in the yogurt on the sides of the glass, and that’s when I pull it out. It has to be cooled before straining. In my experience if it is not heated long enough the yogurt cheese will remain watery and if too long it gets very dry.
-Brad
I’ll see about trying that out. I don’t have the magical pot though , lucky you. 🙏 c
Any clear glass bowl will let you see the progress. Good luck, and please let me know what you think.
-Brad
I was thinking it sounded familiar. Pretty much how they make it. I used to make a great cheese with curds from Kefir . I discovered my Kefir curds had become contaminated , in a very good way, with other bacteria strains and it made a different product.
the name is Viili. It was great then it stopped working and I bought on line what was supposed to be their starter to make Viili but it didn’t work. 👎
I prefer labne. I can get two different kinds at a local "international" market and one of them is made in Turkey. That's the better one but they don't always have it on the shelves. There's an Indian yogurt that's almost as good.
What's old is new again…
A few years back, TFL member @doughooker mentioned the use of acid whey to approximate SFSD bread. This process was described in a patent (US3826850) from 1974:
I'm surprised that the authors of this recent article didn't reference this previous patent. The only difference is that no vinegar/acetic acid was used in the current article.
I've tried this patent method and I was unable to obtain satisfactory results. I used purchased sweet whey powder and lactic acid and malt vinegar. I haven't tried using CLAS because I still haven't gotten around to making CLAS itself. I might try this again if I can think of other ways to achieve the desired results.
BTW, I may be in the minority, but I actually like nonfat Greek yogurt. I get the Aldi (Chobani-made) quarts for about $3—smooth and creamy.
I use whey fairly often and in my experience it is only usable in bread making to a certain extent. Up to maybe 40% as a replacement for water it allows you to skip preferment and make a straight dough that produces bread of comparable quality. But at some point above that it starts destroying gluten. And the problem with fresh whey you get out of your homemade yogurt, or in my case farmer's cheese, is that it is inconsistent so you never quite know the effective range.