Cathy2 wrote:This website is conservative, what surprised me was their expectation to heat the milk to no more than 165 degrees. Until I read it, I had also heated my milk to 180 degrees.
mamagotcha wrote:It's the holding-at-170 that seems to thicken the yogurt up so well, but next time I'll try 165 and see how it does. I don't want to muck about with adding milk powder, but I suspect that holding it at the high temp for a while before dropping to 110 for inoculation and the longer ferment results in some evaporation; essentially, it does the exact same thing as adding the dried milk... increases the ratio of milk solids to liquid.
In Food Microbiology, Adams & Moss wrote:Before addition of the starter culture, the milk is heated to 80-90°C [176-194°F] for about 30 min. Being well in excess of the normal pasteurization requirements for safety, this has a substantial lethal effect on the microflora. All but heat-resistant spores are eliminated so that the starter culture encounters little by way of competition. The heat process also improves the milk as a growth medium for the starter by inactivating immunoglobulins, expulsion of oxygen to produce a micro-aerophilic environment, and through the release of stimulatory levels of sulfhydryl groups. Excessive heating can however lead to the production of inhibitory levels of these compounds. Heating also promotes interactions between whey or serum proteins and casein which increase the yoghurt viscosity, stabilize the gel and limit syneresis (separation of whey).
mamagotcha wrote:Bring 1/2 gallon whole milk to 180 degrees F (I use a thermometer with an alarm to alert me when it reaches the right temperature).
Turn flame to as low as it goes and put a lid on the pot, and try to hold it at about 170-180F for about two hours.
In Milk and Milk Products; Technology, Chemistry and Microbiology, Varnam & Sutherland wrote:A further important effect of heating is the increase in hydrophilicity [tendency to interact with water] of the proteins which reduces syneresis [expulsion of whey] and increases gel firmness. This is a consequence of the covalent attachment between κ-casein and β-lactoglobulin which results in a new surface structure with fewer exposed hydrophobic groups. Maximal hydration is obtained by heating milk to 85°C [185°F] for 30 min, the yoghurt produced after this treatment exhibiting true thixotropic [gel-like] behavior. Increasing the severity of heat treatment further increases hydrophobicity and leads to syneresis and a poor quality yoghurt.
pairs4life wrote:I bought a quart of Fage on Monday for just under $8. It was gone as of yesterday. An east coast FB friend is snowed in and mentioned making granola and crockpot yogurt. I bought a half gallon of organic whole milk today at Trader Joe's for $3.99. I bought a quart of Chobani whole milk yogurt for $6.49, I think I now know why I was big on making yogurt before.
dudefella wrote:
based on the recipes i've seen, is the yield about half of the milk you start with? might start doing this, but if a quart of Chobani is $6.49 and 2 quarts (half gallon) of milk is $3.99, i might be ok with paying Mr. Chobani the 2.49 for labor/time.
further i think i saw that greek yogurt's yield is actually less than half, since you strain it? thanks
. The labor is minimal.Diannie wrote:dudefella wrote:
based on the recipes i've seen, is the yield about half of the milk you start with? might start doing this, but if a quart of Chobani is $6.49 and 2 quarts (half gallon) of milk is $3.99, i might be ok with paying Mr. Chobani the 2.49 for labor/time.
further i think i saw that greek yogurt's yield is actually less than half, since you strain it? thanks
It's Greek yogurt that yields about half. My recipe is about 1:1, 4 cups milk plus yogurt starter plus dry milk gives me (ish) 36 oz yogurt.
dudefella wrote:and 2 quarts (half gallon) of milk is $3.99
Diannie wrote:It's Greek yogurt that yields about half. My recipe is about 1:1, 4 cups milk plus yogurt starter plus dry milk gives me (ish) 36 oz yogurt.
Cathy2 wrote:Yogurt fact sheet from the National Center for Home Preservation
They suggest heating milk to no more than 165 degrees. Once culture has been introduced, to keep it at a temperature of 110 +/- 5 degrees for four to seven hours until set.
In Fermenting Yogurt at Home, NCHFP’s Brian A Nummer wrote:Heat milk to 200°F, stirring gently and (a) hold for 10 minutes for thinner yogurt or (b) hold 20 minutes for thicker yogurt. Do not boil. Be careful and stir constantly to avoid scorching if not using a double boiler.
Rene G wrote:Cathy2 wrote:This website is conservative, what surprised me was their expectation to heat the milk to no more than 165 degrees. Until I read it, I had also heated my milk to 180 degrees.
The 165°F step is for pasteurization and is omitted when using commercial pasteurized milk. The NCHFP website recommends heating at 200°F (93°C) for protein denaturization, somewhat higher than usually suggested.
Heat milk to 200°F, stirring gently and (a) hold for 10 minutes for thinner yogurt or (b) hold 20 minutes for thicker yogurt. Do not boil. Be careful and stir constantly to avoid scorching if not using a double boiler.
Pie-love wrote:Here's a question-- can homemade yogurt (slightly thinned with milk as needed) completely replace cultured buttermilk? Both are acidic dairy products. My initial testing in pancakes yesterday indicated that thinned-yogurt makes a great substitute for buttermilk. Any thoughts on whether buttermilk and yogurt are redundant?
Rene G wrote:Pie-love wrote:Here's a question-- can homemade yogurt (slightly thinned with milk as needed) completely replace cultured buttermilk? Both are acidic dairy products. My initial testing in pancakes yesterday indicated that thinned-yogurt makes a great substitute for buttermilk. Any thoughts on whether buttermilk and yogurt are redundant?
Cultured buttermilk and yogurt have a lot of similarities but are fermented differently and have somewhat different flavor profiles. I'd expect the two would be interchangeable for many cooking applications.
Yogurt is usually made by incubating milk at around 110°F with Lactobacillus bulgaricus and Streptococcus thermophilus, the former for acid production while the latter provides flavor. For buttermilk (and crème fraîche), various subspecies of Lactococcus lactis and sometimes Leuconostoc mesenteroides are often used and the incubation temperature is around 72°F. These bacteria are chosen for their ability to produce lactic acid as well as plenty of diacetyl, which gives the product its buttery flavor.
But it sounds like you've already answered your question. If it tastes good to you, who cares what others (especially dairy microbiologists!) think?
While I haven't used whey, I've read it works just fine.tjr wrote:Reviving...
I've been making whole milk yogurt fairly often. I use a Eurocuisine yogurt maker:Sometimes I use the little jars, sometimes I put in a 1.5 qt Corningware casserole that fits perfectly. Mostly I turn the yogurt into yogurt cheese by straining it until almost no whey remains. Otherwise I use it for cooking and toppings. Since we always have vanilla Activia in the fridge (Ms. R swears by it for digestive problems) I made my starter by making a single jar with 3/4 c milk plus a teaspoon of Activia to eliminate the very strong vanilla taste. Then I've gone multiple generations without restarting.
Lately, to get firmer yogurt, I've been heating to 170-180 in the microwave and holding for around 15 minutes using low power. From the notes above, looks like I might want to go a little hotter and longer for max firmness. I use grocery store whole milk.
Anyone tried using yogurt whey as a starter? That would eliminate the need to sacrifice some cheese production for the next batch. And any advice on yogurt cheese is welcome too. I love the stuff on crackers and bread, just plain or with added herbs or peppers.
In this area, available at FreshMarket, both whole and nonfat @ $5.99/pint.Xexo wrote:I was reading late last summer and found that White Mountain Bulgarian yogurt was highly recommended to use as a starter, and that it lasts for generations.