1 00:00:00,520 --> 00:00:03,600 Speaker 1: Welcome to brain Stuff from house Stuff Works dot com 2 00:00:03,600 --> 00:00:14,480 Speaker 1: where smart happens. Hi Am Marshall Brain with today's question, 3 00:00:14,840 --> 00:00:18,840 Speaker 1: what is mayonnaise? And this question comes up because lots 4 00:00:18,840 --> 00:00:21,319 Speaker 1: of people have no idea what mayonnaise is. You know, 5 00:00:21,320 --> 00:00:23,360 Speaker 1: if you look at butter, most people know that you 6 00:00:23,400 --> 00:00:25,360 Speaker 1: can make butter out of cream. And if you look 7 00:00:25,360 --> 00:00:28,360 Speaker 1: at catchup or something like that, most people know that 8 00:00:28,440 --> 00:00:31,240 Speaker 1: it's made out of a thick tomato sauce. But mayonnaise, 9 00:00:31,360 --> 00:00:33,520 Speaker 1: what what is it? Is it made out of milk 10 00:00:33,720 --> 00:00:37,000 Speaker 1: because it's white? Is it some other substance? If you 11 00:00:37,040 --> 00:00:38,800 Speaker 1: look at the label, you can see that it has 12 00:00:38,880 --> 00:00:41,239 Speaker 1: a lot of fat in it. Some mayonnaises have as 13 00:00:41,320 --> 00:00:44,319 Speaker 1: much as nine fat. So let's take a look at 14 00:00:44,320 --> 00:00:48,120 Speaker 1: where this stuff comes from. It turns out that mayonnaise, 15 00:00:48,200 --> 00:00:50,879 Speaker 1: and here we're talking about real mayonnaise, the kind of 16 00:00:50,880 --> 00:00:53,000 Speaker 1: mayonnaise you could make at home if you wanted to, 17 00:00:53,440 --> 00:00:55,600 Speaker 1: is made out of at least three things, and those 18 00:00:55,680 --> 00:00:59,680 Speaker 1: are oil, a lot of oil, egg yolks, and some 19 00:00:59,760 --> 00:01:03,240 Speaker 1: kind of acid, either lemon, juice or vinegar. There might 20 00:01:03,280 --> 00:01:05,959 Speaker 1: also be some kind of seasonings in there, like salt, 21 00:01:05,959 --> 00:01:09,520 Speaker 1: and maybe something else. But mayonnaise itself is just the 22 00:01:09,520 --> 00:01:13,360 Speaker 1: three things oil, egg, yolks, and lemon juice or vinegar. 23 00:01:13,840 --> 00:01:15,840 Speaker 1: The obvious question is, how are you going to get 24 00:01:15,880 --> 00:01:19,880 Speaker 1: oil and lemon juice to mix together? Because lemon juice 25 00:01:19,880 --> 00:01:23,040 Speaker 1: is water based and oil is oil based, obviously, so 26 00:01:23,240 --> 00:01:25,479 Speaker 1: when you try to mix them together, they're not going 27 00:01:25,520 --> 00:01:27,960 Speaker 1: to mix. Oil and water don't mix. And the magic 28 00:01:28,040 --> 00:01:30,840 Speaker 1: of mayonnaise and mayonnaise really is kind of magic, is 29 00:01:30,920 --> 00:01:34,880 Speaker 1: that the egg is there to act as an emulsifier 30 00:01:35,040 --> 00:01:38,240 Speaker 1: and to make those two things that normally wouldn't combine 31 00:01:38,440 --> 00:01:43,680 Speaker 1: able to combine together to create the unique taste of mayonnaise. Therefore, 32 00:01:43,760 --> 00:01:46,959 Speaker 1: we say that mayonnaise is an emulsion, which is a 33 00:01:47,040 --> 00:01:51,960 Speaker 1: mixture of any two liquids that normally can't be combined chemically. 34 00:01:52,280 --> 00:01:55,840 Speaker 1: Mayonnaise is also known as a colloid. A colloid is 35 00:01:55,880 --> 00:01:59,520 Speaker 1: a mixture composed of tiny particles that are suspended in 36 00:01:59,560 --> 00:02:05,920 Speaker 1: another or immiscible or unmixable material. These particles are usually 37 00:02:06,040 --> 00:02:09,880 Speaker 1: larger than molecules, but less than one one thousand of 38 00:02:09,919 --> 00:02:14,400 Speaker 1: a millimeter in size. Small particles like this don't settle 39 00:02:14,400 --> 00:02:17,200 Speaker 1: out or don't rise to the top, depending on their nature, 40 00:02:17,639 --> 00:02:20,960 Speaker 1: and they will pass right through filter paper. One really 41 00:02:21,000 --> 00:02:23,440 Speaker 1: good example of a colloid that we see all the 42 00:02:23,480 --> 00:02:27,720 Speaker 1: time is homogenized milk. In homogenized milk, they've taken the 43 00:02:27,800 --> 00:02:31,600 Speaker 1: cream and they've broken it up into such tiny particles 44 00:02:31,639 --> 00:02:34,880 Speaker 1: that it remains mixed in with the watery milk. And 45 00:02:34,919 --> 00:02:37,919 Speaker 1: it's the size of the particles that allows that to happen. 46 00:02:38,280 --> 00:02:41,600 Speaker 1: So that's a mechanical colloid, a colloid that was created 47 00:02:41,680 --> 00:02:45,880 Speaker 1: mechanically by breaking those cream particles up into such small, 48 00:02:46,320 --> 00:02:50,720 Speaker 1: tiny spheres. Chemically, you can also create an emulsion, so 49 00:02:51,000 --> 00:02:54,440 Speaker 1: you use chemicals of some sort to break the particles 50 00:02:54,520 --> 00:02:57,160 Speaker 1: up and get them to suspend in a liquid. So 51 00:02:57,240 --> 00:03:00,520 Speaker 1: to make mayonnaise, you start with the lemon juice and 52 00:03:00,639 --> 00:03:04,480 Speaker 1: to that you add some egg yolk eggs, which contain 53 00:03:04,560 --> 00:03:08,840 Speaker 1: an emulsifier called less than bind the ingredients together and 54 00:03:08,960 --> 00:03:12,840 Speaker 1: prevent them from separating. So you add the eggs and 55 00:03:12,919 --> 00:03:15,639 Speaker 1: the lemon juice, and those are going to combine together fine. 56 00:03:16,120 --> 00:03:18,800 Speaker 1: Then you add the oil in a tiny bit, like 57 00:03:18,880 --> 00:03:22,520 Speaker 1: just a few drops at a time, and whisk that 58 00:03:22,639 --> 00:03:25,720 Speaker 1: together with a fork or with an actual metal whisk 59 00:03:26,200 --> 00:03:30,200 Speaker 1: to get the oil and water emulsion started. If the 60 00:03:30,280 --> 00:03:33,560 Speaker 1: chef messes up with this initial mixing step, the whole 61 00:03:33,680 --> 00:03:36,440 Speaker 1: batch isn't gonna work. You have to start very slowly 62 00:03:36,480 --> 00:03:40,200 Speaker 1: with the oil and get the emulsion to start, and 63 00:03:40,240 --> 00:03:43,640 Speaker 1: then you can add more and more oil more quickly 64 00:03:43,720 --> 00:03:48,520 Speaker 1: because the process accelerates as the mayonnaise thickens. Then, if 65 00:03:48,520 --> 00:03:51,800 Speaker 1: you want to add in any seasonings to make flavored mayonnaise, 66 00:03:51,920 --> 00:03:53,840 Speaker 1: you add them in at the end of the process. 67 00:03:54,360 --> 00:03:57,839 Speaker 1: Since homemade mayonnaise isn't cooked, you need to be sure 68 00:03:57,880 --> 00:04:00,560 Speaker 1: to use the freshest eggs possible, and you need to 69 00:04:00,560 --> 00:04:04,120 Speaker 1: be pretty sure that they're free from salmonella. You also 70 00:04:04,200 --> 00:04:06,520 Speaker 1: want to use it quickly. You can store it in 71 00:04:06,560 --> 00:04:09,200 Speaker 1: the refrigerator for two or three days, but after that 72 00:04:09,240 --> 00:04:11,400 Speaker 1: you really should throw it out rather than letting it 73 00:04:11,440 --> 00:04:14,360 Speaker 1: hang out for a week or two. Commercial mayonnaise, which 74 00:04:14,400 --> 00:04:16,320 Speaker 1: is the kind of mayonnaise you buy at the store 75 00:04:16,320 --> 00:04:19,200 Speaker 1: in a jar, will last up to six months in 76 00:04:19,200 --> 00:04:24,599 Speaker 1: the refrigerator. It contains by US law at least oil 77 00:04:24,680 --> 00:04:28,520 Speaker 1: by weight, except for reduced fat and fat free mayonnaises. 78 00:04:29,000 --> 00:04:33,200 Speaker 1: The standard of Identity law also requires that all commercial 79 00:04:33,360 --> 00:04:38,799 Speaker 1: real mayonnaise use only egg as the emulsifier. Reduced fat mayonnaise, 80 00:04:38,800 --> 00:04:43,720 Speaker 1: which isn't considered real mayonnaise anymore, usually contains modified food starts, 81 00:04:43,839 --> 00:04:48,240 Speaker 1: cellulose gel, and other thickeners and emulsifiers. Once you have 82 00:04:48,400 --> 00:04:50,919 Speaker 1: your mayonnaise, you can use it straight up on something 83 00:04:50,960 --> 00:04:53,760 Speaker 1: like a bacon lettuce tomato sandwich, or you can use 84 00:04:53,800 --> 00:04:57,000 Speaker 1: it as a base for other sauces like tartar sauce 85 00:04:57,240 --> 00:05:02,200 Speaker 1: or a Thousand Islands salad dressing. Be sure to check 86 00:05:02,240 --> 00:05:05,360 Speaker 1: out our new video podcast, Stuff from the Future. Join 87 00:05:05,440 --> 00:05:07,960 Speaker 1: how staf work staff as we explore the most promising 88 00:05:08,040 --> 00:05:12,920 Speaker 1: and perplexing possibilities of tomorrow. The hou stef Works iPhone 89 00:05:12,920 --> 00:05:15,880 Speaker 1: app has arrived. Download it today on iTunes.