How to Make Popping Boba: The Science of Spherification

how do you turn juice into these juice-filled balls the answer is verification spherification uses food-friendly chemicals to turn liquids into squishy spheres with a gelatinous outside and a liquid center also called popping boba in this video we'll show you how to make popping boba explain the science behind verification give you tips and tricks for getting the process to work smoothly and tell you how you can turn this fun cooking project into a science project for school [Music] foods used for sparification are typically a liquid or have a liquid-like consistency fruit juice soda yogurt soup or pureed fruit are some good examples ideally your food should be refrigerated before you start once you have chosen a food you will need to gather these materials follow the link in the description for a detailed list first mix the food or liquid you chose with sodium alginate put half a cup of the food into a blender add two grams of the sodium alginate and then another half cup of the food blend until the food and sodium alginate are completely mixed once mixed you might notice that the consistency of the liquid has thickened to be more gel like you may also see some foam this is normal you will need to refrigerate the food alternate mixture for at least an hour or overnight to allow the foam and any bubbles in the mixture to disappear bubbles make it more difficult to form the spheres in the next step while the alginate mixture is resting in the refrigerator prepare the second key ingredient the calcium chloride solution pour 1 cup of water into a clean bowl then add 2 grams of calcium chloride and stir the solution until the calcium chloride has completely dissolved you can use the solution for several days once your food alginate mixture is bubble free take it out of the refrigerator suck some of the liquid up into a syringe and practice releasing the food alginate mixture slowly one drop at a time back into the container this part is tricky and it may take you a few minutes to get the hang of the technique once you can form one drop at a time you are ready to make your popping boba set a timer to one minute then hold your syringe with the food alginate mixture three to four inches above the calcium chloride solution and slowly press the plunger to drop a single drop into the bowl let the drop sit in the solution for one minute and observe what happens after one minute use a spoon to remove the sphere from the calcium chloride solution rinse it in a bowl of water and then take a closer look hold it in your hand and squeeze it slightly how does it feel a well-made popping boba will be round like a ball feel squishy and pop and release liquid when you squeeze it [Music] while the whole process may look like magic it's simply a chemical reaction between sodium alginate and calcium chloride sodium alginate is made from seaweed and consists of alginate negatively charged molecules called polysaccharides and positively charged sodium ions that bind to the alginate molecules when dissolved in food or juice the alginate separates from the sodium ions and forms a liquid when the alginate comes into contact with the calcium chloride solution the alginate molecules bind to the calcium ions forming calcium alginate as the doubly charged calcium ions combined two different alginate molecules simultaneously the solution thickens and becomes gel-like this is why the outside of the popping boba are firmer it is a shell of calcium alginate if removed from the calcium chloride solution soon enough the calcium never reaches the inside of the popping boba so it is still liquid-like the chemical reaction that forms popping boba can be written as the chemical formula two molecules of sodium alginate react with one molecule of calcium chloride to form two molecules of salt and one molecule of calcium alginate [Applause] although the chemistry and technique for making pumping boba are fairly simple getting the conditions just right can be challenging there are four variables that affect the process of spherification the first is the calcium content of the food or liquid that you are trying to make popping boba with too much calcium makes the food and sodium alginate mixture rubbery or too gelatinous instead of a thick liquid this is because the calcium in the food reacts with alginate prematurely sometimes the addition of a few grams of sodium citrate can help the sodium citrate traps the calcium ions and prevents them from reacting with the alginate to make boba from calcium-rich foods or liquids you might also want to consider switching to the reverse sperification process which is described in the science buddies reverse verification video the second variable that can affect spherification is acidity if the ph of a food or liquid is not right the food alginate mixture does not solidify at all but instead dissolves in the calcium chloride solution this verification reaction will only occur in a ph range between four and ten again the addition of sodium citrate can help as it increases the ph of the food alginate solution it can be useful to check the ph of your food alginate mixture with ph test strips before you start this verification process the third variable is technique to make perfectly round spheres you must drop the food alginate mixture one drop at a time if you are struggling to do that with the syringe try using a dropper instead you can also try changing the height from which you drop the liquid into the calcium chloride solution don't get frustrated if your spheres aren't perfect right away this step definitely requires some practice the fourth and last variable is the amount of time the boba spend in the calcium chloride solution the longer you keep the droplets in the calcium chloride solution the thicker their skin will be as the alginate has more time to react with the calcium if you wait long enough you can even solidify the whole sphere try different times to find out which thickness you like best since the sperification process is dependent on many variables you can easily turn the making of popping boba balls into a science project food acidity or calcium content make great independent variables for a science experiment if you want to explore this verification process in more detail for example you could investigate what effects the acidity of a food has on the shape of the popping boba you make or you could try foods with different calcium contents and test how much sodium citrate you have to add to make this verification process work since good puppy boba is spherical or ball like in shape one way to quantify the success of your spherification process for a science project is to measure the longest and shortest dimensions or the diameter and height of the popping boba you make you can measure these by placing the boba on graph paper and counting how many lines it spans in a perfect sphere the diameter and height are the same which foods and liquids make the best popping boba what ph results in the most perfect spheres experimenting with sperification is the best way to find out to get ideas for sperification science projects or thousands of other science and engineering projects visit us online at www.sciencebuddies.org

Channel: Science Buddies

Views: 612,591

Keywords: science, STEM, spherification, direct spherification, reverse spherification, sodium alginate, molecular gastronomy, popping boba

Id: 74RnO_wHX7k

Length: 8min 32sec (512 seconds)

Published: Fri Sep 03 2021