14 replies to this topic

[aimymalik]

Dear All,

 

I need your help,  Can you please confirm,

 

 

Is there UHT yogurt plain or flavoured available in the market.

 

What is effect of UHT to Yogurt.

What is Shelf for yogurt under ambient temperature?

 

Thanks

 

[Tony-C]

Hi aimymalik,

 

There are long life yoghurts for sure. I have not seen a process in which the yoghurt is Ultra Heat Treated and believe this will create an undesirable taste.

 

In my experience there are two ways to manufacture long life yoghurt:

 

1. Hot fill the yoghurt into pack such that the pack is rendered sterile by the heat of the yoghurt (Requires a pack that can withstand heat of the hot yoghurt base and is strong enough such that it does not implode when cooled).

 

2. Repasteurize the yoghurt base and fill via an aseptic system.

 

Both methods mean that the yoghurt is no longer 'live' and require a stabilizer to retain some structure in the yoghurt. You will need to check with local legislation if it is still acceptable to call the product yoghurt.

 

For both methods the packaging should be resistant to moisture loss throughout the life of the yoghurt.

 

Regards,

 

Tony

[Charles.C]

Hi aimymalik,

 

The shelf lives are "extended" to varying degrees, eg -

 

 strawberry UHT yoghurt.png   81.79KB   14 downloads

 

As to effect, Tony's comment is relevant. Some people consider this may also relate to its health benefits, eg --

 

 evolution of types of yoghurt.pdf   232.01KB   113 downloads

 

PS - Welcome to the Forum !

[Tony-C]

Hi aimymalik,

 

The shelf lives are "extended" to varying degrees, eg -

 

strawberry UHT yoghurt.png

 

As to effect, Tony's comment is relevant. Some people consider this may also relate to its health benefits, eg --

 

evolution of types of yoghurt.pdf

 

PS - Welcome to the Forum !

 

Hi Charles,

 

Ref. the image, I don't believe that product is Ultra Heat Treated: These products are later heat-treated and aseptically packed.

 

Ref. evolution of the types of yoghurt, I'm sure that there is some useful information in there but they seem far from knowledgeable in long life yoghurts: Pasteurized and UHT Yogurt - Although these types of yogurt products are produced by the manufacturers in order to prolong the shelf life and/or to decrease the natural tartness of yogurt, the heat treatment may destroy considerable numbers of live and active cultures present.

 

UHT - https://en.wikipedia...ture_processing

 

Regards,

 

Tony

[Charles.C]

H Tony,

 

The yoghurt scene  is clearly a terminological delight for commercial purposes.

 

The tag of “Long life” seems to be simply irresistible.

 

And even in textbooks -

 

 uht yogurt2.png   52.05KB   8 downloads

 

PS - the pic in previous post was categorized under "long life uht". You are correct about the process.

 

PPS - another simple decision-helper -

 

http://www.allaboutf...est-yogurt.html

[Tony-C]

H Tony,

 

The yoghurt scene  is clearly a terminological delight for commercial purposes.

 

The tag of “Long life” seems to be simply irresistible.

 

And even in textbooks -

 

uht yogurt2.png

 

PS - the pic in previous post was categorized under "long life uht". You are correct about the process.

 

PPS - another simple decision-helper -

 

http://www.allaboutf...est-yogurt.html

 

Hi Charles,

 

It is no surprise to me

 

Your link about decision helper is highly amusing rather than offending but please stop putting articles from kitchen chefs into a food manufacturing forum ! http://www.allaboutf...est-yogurt.html

 

I can't fully comment on the forums here. Members can PM me to receive my full list of expletives regarding this article !

Here are some quotes:

 

'*Apparently the temperature used for producing yogurt is considered proprietary information by many yogurt manufacturers. I find this lack of transparency incredibly annoying.

**Best is to make yogurt from raw milk, whereby you turn an already vital food into an even better food.

***Ultra-pasteurization or UHT (Ultra High Temperature)
The reason I asked these yogurt manufacturers if the milk protein, casein, is altered is because UHT is known to do so.

 

****Additives
To reduce my intake of additives, I only buy plain yogurt. But even plain yogurt has had some things added:
milk solids - used to balance out the natural variances in milk composition'

 

* Manufacturers have spent a lot of time, money and resources into a process that works for them. If you want an clue then it is over 80 C and over 2 minutes .....

 

** So it is best to make yoghurt with raw milk including pathogens that will be free to grow whilst the product is incubating?  (sarcasm!)

 

*** Yoghurt processing is designed to alter protein structure including Casein in order for a structure to be formed when fermentation takes place. See *1. Not sure I've seen a UHT yoghurt but I'd be happy to be educated.

 

**** Yoghurt is made from fortified milk not plain milk unless condensed. Not sure what is wrong with milk solids as an 'additive'?

 

As per your 1st comment - I also disagree with the labelling information referenced from the UK but I am 'allegedly' a 'maverick' as described by the people I used to work with over there!

 

Regards,

 

Tony

[aimymalik]

Thank you very much Tony and Charles,

 

Information contributed is very helpfull.

What I understood is there is no UHT Yogurt availbale. Does heat treatment or pasteurization validate longer shelf life. Our supplier is providing us Yogurt with 1 year shelf life and the label says '' If un-opened no need to refrigrate" We are in a country where temprature througout the year is around 35 to 40C.

Regards

 

Aimy

[Charles.C]

Thank you very much Tony and Charles,

 

Information contributed is very helpfull.

What I understood is there is no UHT Yogurt availbale. Does heat treatment or pasteurization validate longer shelf life. Our supplier is providing us Yogurt with 1 year shelf life and the label says '' If un-opened no need to refrigrate" We are in a country where temprature througout the year is around 35 to 40C.

Regards

 

Aimy

Hi Aimymalik,

 

The extended shelf life is a result of the specific process. The process/shelf-life require validation.

 

A few queries -

 

Local manufacture ?

Any information on the manufacturing process ?

Is there a detailed Product Specification ?

Does your suppplier implement any kind of Approval Procedure with respect to the manufacturer, eg Certification to a Recognized FS Standard?

Any official Local Food Product Approval system ?

[aimymalik]

Here is the Technical card

Attached Files

•  Dukat-Dairy yogurt low fat pineapple.pdf   988.76KB   64 downloads

[Charles.C]

Here is the Technical card

Do you require to store it at ambient temperatures ?

[aimymalik]

Do you require to store it at ambient temperatures
 

We require UHT Yogurt with shelflife 1 year. no matter if storage is refrigrated or ambient. 
My question is how come non-UHT yogurt can be safe and retain quality when stored at ambient temprature or even more (becuase on label it only says no need to refrigrate if un opened) for 360 days?

[Charles.C]

The product is stated to be heat treated. i presume this means heated after fermentation since the claimed plate count is very low (although data is "to be confirmed" whatever that means).This further heating is one way to potentially extend the shelf life as compared to traditional yoghurt.

 

My question is how come non-UHT yogurt can be safe and retain quality when stored at ambient temprature or even more (becuase on label it only says no need to refrigrate if un opened) for 360 days?

Traditional yoghurt cannot be stored at ambient temperatures, eg 25degC for any significant time.

 

Tony is likely more familiar with this product than me since he is actively involved in the dairy business.

 

Seems that the 1yr is on the maximum limit of the range of shelf lives offered for this  type of product.

 

Note that the designated storage temperature for the claimed  1yr shelf-life is 2-25 degC. Be careful as to yr proposed distribution/storage.

 

Samples first ? And my other Queries.

(Personally, unless I had previous experience such Product/Supplier/Origin I would, minimally, need to know more regarding the process, product sensitivity,background. Maybe you have all this already.).

 

PS - the reason it suggests refrigeration after opening is probably to minimise any microbial activity due possible contamination from the environment.

[Tony-C]

Hi Aimy,

 

Charles' comments in the previous post have covered your questions.

 

To confirm the product has a long life because it has been 'heat treated' and as such there will be nothing inside to grow and so is fine to store at ambient temperatures. This type of product usually suffers from moisture loss and will deteriorate in quality over time, exposure to high temperatures will accelerate any deterioration.

 

Regards,

 

Tony

[kimkos]

Hi aimymalik,

 

There are long life yoghurts for sure. I have not seen a process in which the yoghurt is Ultra Heat Treated and believe this will create an undesirable taste.

 

In my experience there are two ways to manufacture long life yoghurt:

 

1. Hot fill the yoghurt into pack such that the pack is rendered sterile by the heat of the yoghurt (Requires a pack that can withstand heat of the hot yoghurt base and is strong enough such that it does not implode when cooled).

 

2. Repasteurize the yoghurt base and fill via an aseptic system.

 

Both methods mean that the yoghurt is no longer 'live' and require a stabilizer to retain some structure in the yoghurt. You will need to check with local legislation if it is still acceptable to call the product yoghurt.

 

For both methods the packaging should be resistant to moisture loss throughout the life of the yoghurt.

 

Regards,

 

Tony

yogurt not pack in hot, because hot destroy culture of yogurt.

[Tony-C]

yogurt not pack in hot, because hot destroy culture of yogurt.

 

Clearly you didn't understand my post or you are inferring that you cannot call a product yogurt unless it contains live cultures, in which case there would be no such thing as 'long life yogurt'.

 

Regards,

 

Tony