Final Project: Initial Research

From my proposal, I decided to focus on milk casein plastic. Before starting my experiments, I scoured the Internet for any current information that could help with my exploration of milk casein.

Science Behind It:

Milk is made up of proteins, fat and water. Many of the proteins are made up of casein. When combined with vinegar, the milk forms curds which can be separated and moulded. These curds are actually long chains of the casein protein molecules called polymers – the same building blocks as plastic.

Currently Available Information:

First of all, vegan milk such as soy, oat or almond milk cannot be used when making milk plastic. This is because casein is a protein that can only be found in mammalian milk such as cows and sheep. It is an essential amino acid that provides calcium and phosphorus for skeletal growth. Hence, although I would have loved to experiment with and use plant-based milks in this process, I decided to skip out on it as I knew these milks did not contain the casein protein I needed for the plastic.

I also found that different vinegars can be used to separate the casein protein in the milk, just as long as acetic acid is present. This means that apple cider vinegar, white vinegar and wine vinegars can be used. However, for the purposes of this experiment, I will be using white vinegar as it contains the most acetic acid amongst the list, 4-7%, and it is also the cheapest 🙂

According to Wikihow, whole milk or heavy cream will work the best then 1% or 2% milk. This is probably to do with the amount of casein in the different types of milk. Hence, for this experiment, I decided to use whole milk for the entirety of the process.

Next Steps:

With the information I found, I decided to use 3 different types of whole milk. I have not come across any information on how the quality of milk would affect the casein; however, I would hypothesis that the better quality milk would also result in better quality casein plastic. I picked 3 different milk brands — with all varied in qualities, judged through the different expiry dates. Through my knowledge of food, I would assume that the longer the expiration date, the more processed and lower quality the milk is.