Question on freezing yogurt cultures please.

[Bertie Doe]

Calling homemade yogurt makers. In the past I've used Easiyo NZ yogurt
cultures to inoculate 1.5 litres of warm full cream UHT milk in my Lakemead
electric yogurt machine. Recent supply probs have made me buy an alternative
Bulgarian product online.

If I run out of stock, I nip down to the local Morrison's and buy a small
150 gr tub of Yeo Valley Active, to start another 1.5 litres. It would be
handy to pop a spare tub of Yeo into the freezer as backup. Obviously when
the frozen yogurt is de-frosted in the fridge, it will be perfectly edible.
Question is - would the cultures ( Lactobacillus and Streptococcus )
sufficiently survive, to inoculate a fresh batch? Thanks in anticipation.
Regards Paul.

[graham]

Post by Bertie Doe
Calling homemade yogurt makers. In the past I've used Easiyo NZ yogurt
cultures to inoculate 1.5 litres of warm full cream UHT milk in my
Lakemead electric yogurt machine. Recent supply probs have made me buy
an alternative Bulgarian product online.
If I run out of stock, I nip down to the local Morrison's and buy a
small 150 gr tub of Yeo Valley Active, to start another 1.5 litres. It
would be handy to pop a spare tub of Yeo into the freezer as backup.
Obviously when the frozen yogurt is de-frosted in the fridge, it will be
perfectly edible. Question is - would the cultures ( Lactobacillus and
Streptococcus ) sufficiently survive, to inoculate a fresh batch?
Thanks in anticipation. Regards Paul.

I don't see why not. However, why don't you try the sourdough technique
and dry some, then grind to a powder and, for safety, stick it in the
freezer.

[Bertie Doe]

Post by Bertie Doe
Obviously when the frozen yogurt is de-frosted in the fridge, it will be
perfectly edible. Question is - would the cultures ( Lactobacillus and
Streptococcus ) sufficiently survive, to inoculate a fresh batch?
Thanks in anticipation. Regards Paul.

I don't see why not. However, why don't you try the sourdough technique and
dry some, then grind to a powder and, for safety, stick it in the freezer.

Thanks Graham but I'm not sure how that works. How do you dry it without
killing the culture?

[graham]

Post by Bertie Doe

Post by graham

Post by Bertie Doe
Obviously when the frozen yogurt is de-frosted in the fridge, it will
be perfectly edible. Question is - would the cultures ( Lactobacillus
and Streptococcus ) sufficiently survive, to inoculate a fresh batch?
Thanks in anticipation. Regards Paul.

I don't see why not. However, why don't you try the sourdough
technique and dry some, then grind to a powder and, for safety, stick
it in the freezer.

Thanks Graham but I'm not sure how that works. How do you dry it without
killing the culture?

With sourdough, you spread fresh starter thinly on a piece of non-stick
parchment and cover it with a bowl (perhaps elevated a bit). When the
batter has dried at room temperature, you blitz it and then store it
until needed when you use it to seed a fresh flour/water mix.
Fungi and bacteria go dormant when you dry them - as long as you don't
heat them.
I would imagine that the dry yoghurt cultures are prepared in much the
same way.

[Brian Reay]

Post by Bertie Doe
Calling homemade yogurt makers. In the past I've used Easiyo NZ yogurt
cultures to inoculate 1.5 litres of warm full cream UHT milk in my Lakemead
electric yogurt machine. Recent supply probs have made me buy an alternative
Bulgarian product online.
If I run out of stock, I nip down to the local Morrison's and buy a small
150 gr tub of Yeo Valley Active, to start another 1.5 litres. It would be
handy to pop a spare tub of Yeo into the freezer as backup. Obviously when
the frozen yogurt is de-frosted in the fridge, it will be perfectly edible.
Question is - would the cultures ( Lactobacillus and Streptococcus )
sufficiently survive, to inoculate a fresh batch? Thanks in anticipation.
Regards Paul.

I used to make yogurt a long time ago and once froze a sample to use as a
starter later. As I recall it worked ok but I don’t recall if it was as
good/less active etc. It certainly, basically, worked although my results
tended to be variable at the best of times. I only recall trying it once. I
suspect it was in the freezer a week, maybe two.

[Bertie Doe]

Thanks Graham and Brian. I've decided to freeze the small tub of Yeo Valley
active yogurt. I'll keep it there for 6 weeks, then defrost and inoculate a
fresh batch of UHT. If it fails, I'll still have some Bulgarian dried
culture to fall back on. I'll report back.

[Brian Reay]

Post by Bertie Doe
Thanks Graham and Brian. I've decided to freeze the small tub of Yeo Valley
active yogurt. I'll keep it there for 6 weeks, then defrost and inoculate a
fresh batch of UHT. If it fails, I'll still have some Bulgarian dried
culture to fall back on. I'll report back.

Out of curiosity, do you use a yogurt maker? We used to have a rather neat
one- long since disposed of- but I have been thinking of trying to make
yogurt again. I’ve seen references to using a slow cooker but I would think
they run a bit too warm.

[Bertie Doe]

Post by Bertie Doe
Thanks Graham and Brian. I've decided to freeze the small tub of Yeo Valley
active yogurt. I'll keep it there for 6 weeks, then defrost and inoculate a
fresh batch of UHT. If it fails, I'll still have some Bulgarian dried
culture to fall back on. I'll report back.
Out of curiosity, do you use a yogurt maker? We used to have a rather neat
one- long since disposed of- but I have been thinking of trying to make
yogurt again. I’ve seen references to using a slow cooker but I would think
they run a bit too warm.

Yes, a typo earlier, I wrote Lakemead but they're the Lakeland 1.5 litre :-
https://tinyurl.com/yxdy8nue

https://www.lakeland.co.uk/31794/Lakeland-Multi-Yogurt-and-Soft-Cheese-Maker?gclid=EAIaIQobChMInayl646m4wIV4hXTCh3qwQGAEAQYAiABEgJp7PD_BwE&src=gfeed&efid=EAIaIQobChMInayl646m4wIV4hXTCh3qwQGAEAQYAiABEgJp7PD_BwE:G:s&s_kwcid=AL!49!3!251304408953!!!g!297220727481!&ev_chn=shop&ef_id=EAIaIQobChMInayl646m4wIV4hXTCh3qwQGAEAQYAiABEgJp7PD_BwE:G:

Much better temp control than their earlier 1 litre models. During the
Summer I find 38 C gives better results than the default 42 C. Semi skimmed
will still produce a firm yogurt but full cream milk is better. I prefer to
use UHT because there's no boiling and cooling involved, you simply heat to
38 C and leave it in the machine for say, 10 hours.

It comes supplied with a strainer for soft cheese or Greek style but I
haven't tried it yet.

[Brian Reay]

Post by Bertie Doe

Post by Bertie Doe
Thanks Graham and Brian. I've decided to freeze the small tub of Yeo Valley
active yogurt. I'll keep it there for 6 weeks, then defrost and inoculate a
fresh batch of UHT. If it fails, I'll still have some Bulgarian dried
culture to fall back on. I'll report back.
Out of curiosity, do you use a yogurt maker? We used to have a rather neat
one- long since disposed of- but I have been thinking of trying to make
yogurt again. I’ve seen references to using a slow cooker but I would think
they run a bit too warm.

Yes, a typo earlier, I wrote Lakemead but they're the Lakeland 1.5 litre :-
https://tinyurl.com/yxdy8nue
Much better temp control than their earlier 1 litre models. During the
Summer I find 38 C gives better results than the default 42 C. Semi skimmed
will still produce a firm yogurt but full cream milk is better. I prefer to
use UHT because there's no boiling and cooling involved, you simply heat to
38 C and leave it in the machine for say, 10 hours.
It comes supplied with a strainer for soft cheese or Greek style but I
haven't tried it yet.

That you, I will have a look in Lakeland.

I tried making soft cheese once- once was enough. It tasted terrible, so
bad I vowed never to try again. I hope you have better luck.

[Kev]

Post by Brian Reay

Post by Bertie Doe
Thanks Graham and Brian. I've decided to freeze the small tub of Yeo Valley
active yogurt. I'll keep it there for 6 weeks, then defrost and inoculate a
fresh batch of UHT. If it fails, I'll still have some Bulgarian dried
culture to fall back on. I'll report back.

Out of curiosity, do you use a yogurt maker? We used to have a rather neat
one- long since disposed of- but I have been thinking of trying to make
yogurt again. I’ve seen references to using a slow cooker but I would think
they run a bit too warm.

I make mine in a slow cooker...

Pour in the milk (I use a 2 litre carton) and heat to just above 82C,
takes about 3 hours in mine.
Switch off and let it cool down to about 45C (another 2 or 3 hours
depending on ambient temp)
Mix your starter (I keep a little container worth back each time) with
some of the warm milk and stir into the rest of the milk
Cover with something insulating (I use an old duvet)
Leave around 12 hours
Its OK to eat then, but my wise likes a thick "greek yogurt" type
texture, so I spoon it into a colander lined with a bit of muslin and
drain for a few hours.
Put in container and in the fridge
Yummy

[Brian Reay]

Post by Kev

Post by Brian Reay

Post by Bertie Doe
Thanks Graham and Brian. I've decided to freeze the small tub of Yeo Valley
active yogurt. I'll keep it there for 6 weeks, then defrost and inoculate a
fresh batch of UHT. If it fails, I'll still have some Bulgarian dried
culture to fall back on. I'll report back.

Out of curiosity, do you use a yogurt maker? We used to have a rather neat
one- long since disposed of- but I have been thinking of trying to make
yogurt again. I’ve seen references to using a slow cooker but I would think
they run a bit too warm.

I make mine in a slow cooker...
Pour in the milk (I use a 2 litre carton) and heat to just above 82C,
takes about 3 hours in mine.
Switch off and let it cool down to about 45C (another 2 or 3 hours
depending on ambient temp)
Mix your starter (I keep a little container worth back each time) with
some of the warm milk and stir into the rest of the milk
Cover with something insulating (I use an old duvet)
Leave around 12 hours
Its OK to eat then, but my wise likes a thick "greek yogurt" type
texture, so I spoon it into a colander lined with a bit of muslin and
drain for a few hours.
Put in container and in the fridge
Yummy

Thank you.

[graham]

Post by Kev

Post by Brian Reay

Post by Bertie Doe
Thanks Graham and Brian. I've decided to freeze the small tub of Yeo Valley
active yogurt. I'll keep it there for 6 weeks, then defrost and inoculate a
fresh batch of UHT. If it fails, I'll still have some Bulgarian dried
culture to fall back on. I'll report back.

Out of curiosity, do you use a yogurt maker? We used to have a rather neat
one- long since disposed of- but I have been thinking of trying to make
yogurt again. I’ve seen references to using a slow cooker but I would think
they run a bit too warm.

I make mine in a slow cooker...
Pour in the milk (I use a 2 litre carton) and heat to just above 82C,
takes about 3 hours in mine.
Switch off and let it cool down to about 45C (another 2 or 3 hours
depending on ambient temp)
Mix your starter (I keep a little container worth back each time) with
some of the warm milk and stir into the rest of the milk
Cover with something insulating (I use an old duvet)
Leave around 12 hours
Its OK to eat then, but my wise likes a thick "greek yogurt" type
texture, so I spoon it into a colander lined with a bit of muslin and
drain for a few hours.
Put in container and in the fridge
Yummy

I think those temperatures are critical. I have a warm cupboard (the
warm air ducts to the upper floor are in the wall) that is ideal for
bread dough. However, when I tried putting the yoghurt mix in there to
ferment, it thickened but the texture was strange. Think mozzarella
strings. I never had that problem with an electric maker, nor using the
heat from a gas pilot light.