SPOILAGE INDICATOR FOR MILK

Hi all! Welcome to another episode of latest in food science and technology developed by CSIR-CFTRI Mysore, India. Today's topics is all about milk and its spoilage indications. 

Milk is a nutritious liquid secreted by the mammary glands of all mammals. Protein named casein and calcium ions imparts white colour to it. It is a complete food, with all the essential nutrients in it. It is rich in calcium, vitamins, carbohydrates (lactose/milk sugar), proteins and fats. Milk is used for most of dishes, starting from coffee/tea to all mouth watering sweet dishes. In short we use milk every morning and night. Without milk our day will be incomplete. But what's more annoying is when milk is spoiled. I will be cramped to see the milk spoiling; much irritating!

Milk is spoiled due to the bacterial growth in it. There are 7 types of microbes involved in spoilage of milk. Lactobacilli, Micrococci, Staphylococci, Pseudomonas, Coliforms, Bacilli and yeasts can be identified in spoiled milk. 

How to identify spoiled milk?

Odour test: We usually indicate the milk spoilage by its odour. The spoiled milk emits foul smell. 

Heating: The spoiled milk forms more turbid particles while heating. Water separates and the milk chunks forms a precipitate. 

Spoilage indicator: The department of Food Packing and Technology, CSIR-CFTRI have developed a colorimetric indicator to check the freshness of milk. 

The colorimetric indicator strip is similar to the pH indicator strip. The strips are stuck to the milk pouch and the colour of the strip is denoted after sometime. 

 If the strips are in green colour, then the milk is fresh and safe to use. 

 If the strips turns orange then the milk is likely to get spoiled and should be used immediately. 

 If the strip turns red then the milk is spoiled and no longer safe for usage. 

This technique is simple, cost effective and easy to use. I think this milk spoilage indicators have to be widely used in order to reduce the wastage of milk and stay fit and healthy by consuming fresh milk. 

Do share if you have guys have any other methods used to identify the spoilage of milk in the comment section. Till then, keep reading 'What's around us' for more such articles. 

Special thanks to Department of Food packing and technology, CFTRI and staff members.