Milk kefir question.

[Mary-Thea]

Hi there,


My name is Mary-Thea and I'm from a small town called Castleisland in County Kerry, Ireland.


I am looking for some help, please!! I hope you don't mind me coming on here with a slightly different angle, but I thought who better to ask to help me solve my problem than homebrewers!


I have a small local business making milk kefir, which is a fermented probiotic beverage. I make it the traditional way by using live kefir grains. When making it this way you can only use glass appliances, plastic strainers, and plastic/wooden spoon. The grains are added to milk, left for 24 hours to ferment, the grains are then strained out, the resulting milk is the kefir, and the grains are re-used again (as they are living organisms, they feed off lactose in the milk as their energy source). Commercially made kefir is made using powdered cultures, and so stainless steel can be used.


I'm currently trying to make my process more efficient. I have a large 50 litre glass jar with a 15cm opening on top, and a small 3cm jowl on the bottom. I'm trying to figure out a way to remove the grains from the jar without them having to be constrained. Below are the methods I've tried so far:


1. I've tried leaving them loose in the jar and draining them through the bottom jowl, but they get stuck and block the exit.


2. I've tried fishing them out from the top but because its narrower than the body of the jar it's a difficult task.


3. I've tried putting them in a muslin bag, but when the milk enters the bag and interacts with the grains the milk thickens (expected), and so then it doesn't leave the bag. What ends up happening is the milk inside the bag turns to cheese over the course of the fermentation, and the milk outside the bag doesn't ferment!


4. I've tried the backslop method but the ratio required would be 3:1 which slightly defeats the purpose of trying to be more efficient.


5. I've tried a glass infuser on a smaller scale but the same issue as the muslin bag arises.


6. My most recent feat was to make a self supporting muslin bag that would expand in the jar and allow all the milk and grains to interact. But I cannot find any suitable material for the supporting bit- it needs to hold its own shape but also be flexible. I ordered a polyester fibreglass rod, which is PERFECT, but it's not foodsafe!!


So yes, if anybody has any suggestions or opinions or anything at all I would greatly appreciate your help!

 

[Chippy_Tea]

Welcome to the forum Mary please read your private messages. thumb

 

[Cyberjip]

Sorry and excuse my ignorance but why is it specifically that you cannot use large stainless steal pots?

Is it not possible to get a large glass jar with a larger opening at the top?

 

[Mary-Thea]

Thanks for your response. Kefir is acidic, so there is risk of a reaction with metals. While stainless steel is considered inert, the safest option is considered to be glass.
I have searched far and wide for a large glass jar with a larger opening but haven't come across anything that is suitable. I'll keep looking though. Potentially I could see if a glass cutter could modify the jar that I have.

 

[Cyberjip]

If your dead set against stainless and you are not getting good results with constricting your grain then I think modifying your existing jar, or perhaps even better, trying to find someone who can make you the jar that you want is your best option (this way you still have your original functional jar, modifying that and it breaking would be a disaster)

Craft glass blowers or perhaps a larger glazing company might be able to do it for you. But I am only guessing as I dont know your exact requirements.

Edit, couple of words

 

[cheeseyfeet]

Sterilised glass marbles in a layer at the bottom to create a filter of sorts with a large surface area unlikely to block?

 

[Mary-Thea]

I almost had the self supporting bag working but just need to find a more suitable material instead of Fibreglass

Yes, very true. Instead of modifying the jar I have I should try to get some quotes for a custom made jar. Thanks for your comments, much appreciated.

 

[Mary-Thea]

Marbles! Well this is something that never even entered my mind! Brilliant! I might run in to a problem when trying to drain the kefir when it’s ready then? Or am I picking your idea up incorrectly?

 

[cheeseyfeet]

No that’s it, I’m thinking the liquid should drain through them leaving the grains which can be recovered when you empty the marbles out.

worth a try if your kefir isn’t too thick.

 

[Mary-Thea]

@cheeseyfeet Definitely worth a try, thank you!