We’re having de-ja-moo as we’re here again with a shipping guide about dairy products…but this time, moo-ve over cheese, we’re covering milk and yogurts. We curd pack food goods in our sleep, so read on for the best advice on shipping your chilled dairy products – legend-dairy!
Right, we’re milking these dairy puns now (get it?) so on to the first topic – why do milk and yoghurts need to be kept cold?
Why do milk and yoghurts need to be kept cold?
Like cheese, milk and yoghurts are made from different ingredients that need to be kept at chilled temperatures (4˚C or lower) throughout the shipping and storage process.
These are:
Milk
- Water (around 87% of milk composition is water)
- Fats
- Vitamins
- Minerals
- Protein
- Carbohydrates
Yoghurts
- Milk
- Harmless bacteria which causes it to ferment
- Flavourings and sweeteners
The proteins and fats in milk make good homes for bacteria if kept in warm conditions, so keeping this product cold is the best way to extend its shelf life and keep it fresh for as long as possible. Yoghurts are primarily made of milk, so they be default also need to be kept cold.
What happens if milk and yoghurt get too warm?
If milk gets too warm, it will curdle quickly and start to go rotten. Bacteria will start to grow and multiply quickly, even if you put it back in the fridge. In addition, putting warm milk into a fridge will raise the internal temperature, so causing the fridge to work harder to cool back down.
You will be able to smell a sour odour if milk has spoiled – this is a byproduct of the lactic acid that is produced by bacteria. It may be lumpy and yellow.
Yoghurt again has the same issue, with bacteria growth and curdling. It may be more tolerant than milk to a degree but both of them should be kept in cold conditions.
Spoiled yoghurt changes in appearance – it may be mouldy with black or green spots and/or have liquid floating at the top. It won’t taste right and may have a sour smell.
Packaging properly
Your packaging needs will vary depending on a) the packaging of the milk or yoghurt in question and b) the temperature in general. Seasonal considerations are very important – during the Summer months, you will likely need more coolants inside your packaging than in the Winter.
As a rule:
- Pack the heaviest items at the bottom – you don’t want squash more delicate items like small yoghurt pots with heavy milk cartons on top.
- Pack the gaps between products with packaging fillers to prevent damage – depending on the ice packs or coolants you are using, you can also use these, but be aware that some ice packs aren’t very strong and may burst. Of course, if you use RecyCool-Ice ice packs, this won’t be an issue, as they are extremely strong and durable.
- Make sure items with similar temperature requirements are shipped together and not with items that may need to be kept frozen or warmer.
- Keep an eye on the weather and use more or less coolants depending on the season.
- Think about the final destination too – is it going somewhere where it will be quickly transferred to a cold storage area? If not, use extra coolants to prevent against spoiling should the shipment be delayed moving into cold storage, or delayed in general.
- It’s important to account for the risk of liquid damage – just in case any milk cartons or bottles do break. Waterproofing the inside of your package is a good idea, so any leaks are contained, and also using packaging boxes with waterproofed outsides.
Resources
- http://www.coolboxsolutions.co.uk/category/shipping-guides/ – our range of Shipping Guides including Fish, Fruit, Cheese and Chocolate.
- DairyUK – https://www.dairyuk.org/the-uk-dairy-industry/
