Soft Drinks - Pasteurisation Time/Temp (PU's)

We are developing a new soft drink.  It will not be carbonated and will have a pH of <3.5.

We will be producing this in house and wondering if there are guidelines for the time/temperature we should be pasteurising at?  We will be pasteursing in bottle using a large water bath.

We will be using a pasteurising computer that lets us input the z value, tref, pu's etc.

Anyone know of any guidelines/standards?

Here is a place to start

Examples of high-acid foods include jams and jellies, pickles, and most fruits. Because there is no fear of Clostridium botulinum growth, these foods require much less heating than low-acid foods. To be safe, such foods need only to reach pasteurization temperatures. For foods with a pH value of 3.5 or less, 175°F (79.5°C) is a sufficient pasteurization temperature. Those foods with a pH range between 3.5 and 4.0 have a recommended pasteurization temperature of 185°F (85°C). For foods with a pH range of 4.0 to 4.3, the recommended pasteurization temperature rises to 195°F (90.5°C). Foods with a pH value between 4.3 and 4.5 have a recommended pasteurization temperature of 210°F (99°C). These pasteurization temperatures are sufficient to kill all microorganisms except for bacterial spores. Since the spores will not grow because of the low pH, the food is considered commercially sterile. A high-acid food will therefore not need the high-temperature process that a low-acid food requires. A high-acid food may typically be processed in a hot water or steam bath at atmospheric pressures – no pressure-cooking is required. For this type of processing, the sealed container is heated in the bath until the internal temperature of the slowest heating point reaches the recommended pasteurization temperature for two to ten minutes depending on the pH value and other properties of the food. The time required to reach this temperature will vary and is usually set by a Recognized Process Authority after reviewing the food, evaluating the process, and perhaps conducting heat penetration tests.

https://extension.ok...operations.html

The Campden guide is the reference source I've encountered most widely in the UK: https://www.campdenb...s.php?pubsID=65

What's in your drink? Obviously not expecting you to divulge the full recipe, but some soft drink ingredients cope with heat treatment better than others. Baths can be laborious if you're doing any sort of significant volume as you've got the heating time each time you load them, as well as the hold time.

I've encountered a range of processes with temperatures ranging from 75C to 90C and hold time anywhere from 5 to 20 minutes. You'll possibly need to have a think about your particular ingredients, as whilst pathogen control is "relatively" easy given your pH, there are some potential soft drink ingredients that can carry a fairly hefty spoilage organism loading, and this may therefore end up being the bigger challenge to address if you're aiming for shelf-stable / ambient end product.

The Campden guide is the reference source I've encountered most widely in the UK: https://www.campdenb...s.php?pubsID=65
 
What's in your drink? Obviously not expecting you to divulge the full recipe, but some soft drink ingredients cope with heat treatment better than others. Baths can be laborious if you're doing any sort of significant volume as you've got the heating time each time you load them, as well as the hold time.
 
I've encountered a range of processes with temperatures ranging from 75C to 90C and hold time anywhere from 5 to 20 minutes. You'll possibly need to have a think about your particular ingredients, as whilst pathogen control is "relatively" easy given your pH, there are some potential soft drink ingredients that can carry a fairly hefty spoilage organism loading, and this may therefore end up being the bigger challenge to address if you're aiming for shelf-stable / ambient end product.

Definitely worth getting hold of the Campden guide IMO.

Given the nature of the products you'll be somewhat less vulnerable to thermal damage from pasteurisation, but also have the added advantage that the hot brewing process should give you relatively low micro loading going into the pasteurisation. Probably worth doing a bit of micro (if not already done) on the drinks prior to pasteurisation, but I'd expect the pasteurisation to really only need to be dealing with any post-brewing contamination and anything inside the bottles prior to use, so you'll probably not need to worry too much about going over the Campden recommendations to deal with spoilage. Having spent quite a lot of time using bath pasteurisers, this is a good thing as anything you can do to speed them up without cutting safety corners is usually a good thing operationally

Hi Scampi,

If u dont mind i want to ask you some question regarding to this article, this is very interesting and makes me wondering about pasteurization process

If we choose to use  the alternative process with hot fill hold, can we completely avoid reheating after the cooling process? Would the product remain stable if stored at room temperature? And does the packaging used need to be sterile, or is it primarily important for the packaging to be clean? I am curious whether this method can be applied for packaging products using large containers such as drums and jerry cans.

Best regards,

Susi

Here is a place to start

Canning high-acid foods

Examples of high-acid foods include jams and jellies, pickles, and most fruits. Because there is no fear of Clostridium botulinum growth, these foods require much less heating than low-acid foods. To be safe, such foods need only to reach pasteurization temperatures. For foods with a pH value of 3.5 or less, 175°F (79.5°C) is a sufficient pasteurization temperature. Those foods with a pH range between 3.5 and 4.0 have a recommended pasteurization temperature of 185°F (85°C). For foods with a pH range of 4.0 to 4.3, the recommended pasteurization temperature rises to 195°F (90.5°C). Foods with a pH value between 4.3 and 4.5 have a recommended pasteurization temperature of 210°F (99°C). These pasteurization temperatures are sufficient to kill all microorganisms except for bacterial spores. Since the spores will not grow because of the low pH, the food is considered commercially sterile. A high-acid food will therefore not need the high-temperature process that a low-acid food requires. A high-acid food may typically be processed in a hot water or steam bath at atmospheric pressures – no pressure-cooking is required. For this type of processing, the sealed container is heated in the bath until the internal temperature of the slowest heating point reaches the recommended pasteurization temperature for two to ten minutes depending on the pH value and other properties of the food. The time required to reach this temperature will vary and is usually set by a Recognized Process Authority after reviewing the food, evaluating the process, and perhaps conducting heat penetration tests.

https://extension.ok...operations.html

Hi Scampi,

 

If u dont mind i want to ask you some question regarding to this article, this is very interesting and makes me wondering about pasteurization process

If we choose to use  the alternative process with hot fill hold, can we completely avoid reheating after the cooling process? Would the product remain stable if stored at room temperature? And does the packaging used need to be sterile, or is it primarily important for the packaging to be clean? I am curious whether this method can be applied for packaging products using large containers such as drums and jerry cans.

 

Best regards,

Susi

What product are you packing, and what are the actual process steps you're hoping to use?

IMEX with hot fill you're effectively using the heat of the product to "pasteurise" the inside of the container. The packaging is clean but not necessarily sterile prior to use.

With liquid hot-fill processes there is usually an inversion step where the filled packaging is turned upside down whilst still hot, as this ensures that the upper parts of the packaging and the inside of the lid are also "pasteurised" via contact with the hot liquid. Not sure how practical that would be for jerry cans, and for drums (200kg? 250kg?) I'm not sure it will be at all viable. If you fill into drum liners, as is commonly the case with many drums, I'm also not sure how you'd validate it and/or actually get reliable results, as the "crinkly" bit where the liner bunches up can provide all sorts of places for microorganisms to hide.

If you need to make an ambient-stable product in these larger formats, and you don't want to use preservatives but your liquid isn't inherently micro stable, then you may want to look into aseptic filling options. It'll certainly have some upfront costs in terms of fillers, but it is a widely used approach for lots of liquid products in industrial pack sizes.

My very best advice on this is to have someone prepare a thermal process for you---time/temp/hold etc will all be included, there would also be a range of allowable variations included

As for large volumes, there is no reasonable way you could manage those and have them shelf stable, far too many variables

Perhaps, instead, you should be looking at making a concentrated syrup that the end user would dilute, mix, bottle and pasteurize

Hire a lab/university to assist     it's money well spent (and it's all cheaper than a recall)

first of all, thank you so much for replying to me

My product is a fruit squash with pH < 3. I'm actually planning to use medium-sized jerry cans with a capacity of 30 liters so that they can still be placed lying down. From some references I've read, besides flipping the packaging, another alternative is to lay the packaging down horizontally. Something along those lines.
 

What product are you packing, and what are the actual process steps you're hoping to use?

 

IMEX with hot fill you're effectively using the heat of the product to "pasteurise" the inside of the container. The packaging is clean but not necessarily sterile prior to use.

With liquid hot-fill processes there is usually an inversion step where the filled packaging is turned upside down whilst still hot, as this ensures that the upper parts of the packaging and the inside of the lid are also "pasteurised" via contact with the hot liquid. Not sure how practical that would be for jerry cans, and for drums (200kg? 250kg?) I'm not sure it will be at all viable. If you fill into drum liners, as is commonly the case with many drums, I'm also not sure how you'd validate it and/or actually get reliable results, as the "crinkly" bit where the liner bunches up can provide all sorts of places for microorganisms to hide.

 

If you need to make an ambient-stable product in these larger formats, and you don't want to use preservatives but your liquid isn't inherently micro stable, then you may want to look into aseptic filling options. It'll certainly have some upfront costs in terms of fillers, but it is a widely used approach for lots of liquid products in industrial pack sizes.

My very best advice on this is to have someone prepare a thermal process for you---time/temp/hold etc will all be included, there would also be a range of allowable variations included

 

 

As for large volumes, there is no reasonable way you could manage those and have them shelf stable, far too many variables

 

 

Perhaps, instead, you should be looking at making a concentrated syrup that the end user would dilute, mix, bottle and pasteurize

 

Hire a lab/university to assist     it's money well spent (and it's all cheaper than a recall)