Ice Cream: a lovable treat for many which consists of milk, sugar, vanilla and flavorings. But, do you really understand the process of how it gets from the cow to your cone? Engineers have been involved every step of the way to ensure that it comes out perfectly.
The process begins with biological engineers who, early in history, bred special cows called Guernsey cows. These cows produce extra creamy milk which is already perfect for ice cream. Then agricultural engineers investigated different types of grass until they found the perfect blend of grass to give the cows. The type they found is a lighter kind with a simpler complexity of proteins so that it is easy to digest. It holds a myriad of vitamins and nutrients that cows need to be healthy; which also benefits the farmer because they can raise more cattle. When it is milking time, the cows get their utters attached to suction cups that suck the milk into large glass tanks which monitor the amount of milk the cow is producing. Mechanical engineers figured out how to make machines in a large scale to create perfect ice cream. The milk travels to a large mixer where sugar, dextrose, and skim milk powder is added to the milk. Chemical engineers had to figure out the perfect ratio between all of the different ingredients. To prevent any germs from the milk being transferred into the final product, the mixture is heated to 690C during the process of pasteurization. Also, the workers use another process, called homogenization, which uses high pressure to change the fat molecules into a smaller and more stable arrangement which results in the ice cream becoming creamy and fluffy. The mixture is then cooled to 20C and left to sit to improve the texture while being automatically monitored while it is still in liquid form. It then travels into a large tub where flavors are added. The product is then packaged and frozen in a large freezer. In less than a day, wholesalers distribute the ice cream in a fleet of trucks. Logistical engineers figure out the most efficient ways to transport the ice cream by considering factors such as greenhouse gasses, cost, wear and tear, and labor needs.
I personally feel that the most important process engineers had to consider is the pasteurization process. Pasteurization is where you heat the mixture to a certain temperature so that any bacterium is killed (for ice cream, you have to heat it to 690C for 30 min.). This process helps extend the expiration date of the product and it’s healthier for humans due to fewer risks of bacterial contamination. Mechanical engineers have invented the batch pasteurizer: a device surrounded by a jacket (heating medium) which has an agitator motor, and a shaft that spins the mixture so that it is heated equally. There are three different thermometers that monitor the temperature of the liquid: recording thermometer, air space thermometer, and indication thermometer. If I was to improve this system as an engineer, I would heat it to a higher temperature so it doesn’t have to remain at a high temperature as long. In a recent study, the American Public Health Association discovered that if they heat the mixture to 93.330C for three seconds, they kill the bacteria and it is safe to eat. To get a feel for the impact of this discovery, I’m going to give an example. Let’s say that each farm makes 10 batches of ice cream per day. Subtracting out 65 days for holidays and weekends, that’s 3,000 batches per year. If there are 500,000 farms in America, then there are 1,500,000,000 batches of ice cream per year. With a savings of 30 minutes per batch, and an average of $200.00 per hour to run equipment, that would save $15 million dollars per year! I think this will improve the whole process because it will be faster, more efficient, and could potentially save millions of dollars.
Engineers: people who try to improve the life of people by solving technical problems. It can be as simple as improving the ice cream process or as complex as creating a way for people to walk on Mars.
The winners of the 2017 EngineerGirl Essay Contest have been announced! NAE President C. D. Mote, Jr. said, "Students’ devotion to protecting endangered animals is always inspiring to me, and their doing so through engineering, which is about solving problems of people and society, is doubly so. Congratulations to the winners!" Check out the link below to read the wonderful essays.