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Cookie Dough Fudge Mint Chip 4.4 – THE ONE



The ice cream batter is from here, unchanged


Fudge Ice Cream

2 cups whole milk, divided

1/2 cup Dutch process cocoa

1 cup fat-free sweetened condensed milk

2 teaspoons vanilla extract

1 (12-ounce) can evaporated low-fat milk

Dash of salt

Heat 1 cup whole milk in a heavy saucepan over medium-high heat to 180° or until tiny bubbles form around edge (do not boil). Remove from heat, and add the cocoa, stirring with a whisk until cocoa dissolves. Cool to room temperature.

Combine 1 cup whole milk, condensed milk, vanilla, evaporated milk, and salt in a blender, and process until smooth. Add cocoa mixture; blend well. Pour mixture into the freezer can of an ice-cream freezer; freeze according to manufacturer’s instructions.


Chocolate chips:

30gr dark chocolate

1 tsp butter

Gently melt the chocolate and butter together, until well combined.

Thinly spread on parchment paper, and let cool.

Freeze for 1/2hour or longer, until solid enough to break into smaller pieces. Break into smaller pieces (duh!) and return to the freezer in a suitable box, until needed.


Eggless cookie dough:

2 cups all purpose flour

1 cup brown sugar

1 cup white sugar

3/4 cup butter, melted

4-5 tbsp milk

Mix flour and sugars in a bowl. Stir in the melted butter until you get a crumbly mixture. Add the milk, one spoonful at a time, and mix well, until you can form a ball of dough.

Use about a 1/4 of the amount for this ice cream, and freeze the rest for later use.


Mint Syrup

However much you want sweetened condensed milk

Peppermint essence, as desired

Mix together


Mix the ice cream batter with the chips and the cookie dough. Swirl in the mint syrup. Enjoy!


This is what I was looking for! The ice cream is fudgy, the chips melt in your mouth, the cookie dough adds a great texture and the mint syrup is just right, without overpowering anything. Oooooooh! Good stuff!


Cookie Dough Fudge Mint Chip 4.0- a four-way



I have found a likely new fudge ice cream recipe and I had such faith in, that I divided it in to four CDFMC experiments:


1. Fudge ice cream with plain cookie dough and white mint chips.

As I said before, mint flavored chips are not available where I live, so I tried to make my own.

In this recipe, I melted some white chocolate with a teaspoon of butter and half a teaspoon of PPM (short for peppermint essence), and spread it out thinly on baking paper to solidify. That didn’t work, so after it cooled, I transferred it to the freezer for it to actually solidify. When it finally did, I broke it down to small bits and kept it cool until it was time to add it to the ice cream.

The purpose of the butter was to make the chocolate more ‘melt in your mouth straight out of the freezer’ and less ‘horrible bits of plastic’ (as it was in the first attempt). I also spread out the melted chocolate very thinly, so it will be even easier for it to melt on the tongue. 



2. Fudge ice cream with plain cookie dough and dark mint chips.

Same as the previous one, only I used dark chocolate instead of white baking bits. These are two interpretations to ‘mint chip’.



3. Minty-Fudge ice cream with plain cookie dough and dark chips.

This time, I added some PPM to the ice cream batter, after it was churned, and hoped for the best. The chips where dark chocolate, melted down with butter, spread out and frozen, just like the rest of them.




4. Fudge ice cream with plain cookie dough, dark chips and mint syrup.

In this recipe, I took the mint part as a completely separate entity, that is not related to either the ice cream, the chips or the cookie dough, and I inserted it as a syrup. I was a bit lazy this time and didn’t make my own syrup, but instead I used sweetened condensed milk, to which I added some PPM. I have previously tested the sweetened condensed milk’s freezing properties and established that it maintains its fluid qualities at low temperatures, so it was a good candidate for this experiment.

 Full recipe in a post of it’s own.

This is The One.


More crazy thoughts, even though I found The One:

 I though about making minty cookie dough, but the way mint and cookie dough are separated in name CDFMC does not, in any way, imply ‘minty cookie dough’. The context is just wrong for it. The flavor might work, so I might still try it out one day, but I would still have to give it some though before calling it CDFNC (yes, I’ve gone crazy, but there’s nothing new about that).

However, the cookie dough may be ‘fudgy cookie dough’, and for that, I have just the recipe! Soon I will reveal my Brownies experiments and all will be clear. 


Cookie Dough Fudge Mint Chip 3.0



So, I gave in. I used food coloring. Only a little, but along with the guilt of cheating, came a realization that the color makes it taste more “right”. The psychology of eating with your eyes must be true.

Another cheat is the fudge. Store-bought vanilla fudge. I’m so ashamed.

This version of the Cookie Dough-Fudge-Mint-chip ice cream is compiled of a light-green minty ice cream, with cookie dough, vanilla fudge, and white chocolate chips.

The batter itself looks and tastes wonderfully refreshing, like a light breeze in the spring time. The leaf-green color really helps form the spring day in your mind, as you taste the soft, sweet mint that melts on your tongue.



This is still not the winner, but it’s pretty nice (and simple).

The minty batter is the same recipe as my first attempt (only with a bit of green food coloring in it). The cookie dough is still the one from The Cupcake Project. The fudge is store-bought vanilla fudge (which turned out to be a bad idea). But the chocolate chips are what I’m really proud of.

My biggest problem with chocolate chips in ice cream is the fact that they are so hard and flavorless when they’re cold. Kind of feels like chewing on plastic bits.

The simplest solution to this is to make the chocolate more “melty”, by changing its fat contents. The more fat, the easier it melts. The fat also has to be the right kind, one with a low melting temp, so it will melt on your tongue, but still be able to freeze.

The only problem is, that makes the “chips” or “fudge” a little fussy to handle when preparing the ice cream. You have to work fast, before it melts in your hands.


For the chocolate chips:

30gr chocolate (I used both white and dark chocolate)

1 tsp of butter

Gently melt the chocolate and butter together, until well combined.

Thinly spread on parchment paper, and let cool.

Freeze for 1/2hour or longer, until solid enough to break into smaller pieces. Break into smaller pieces (duh!) and return to the freezer in a suitable box, until needed.


Mix the ice cream with the white fudge chips and the cookie-dough, freeze and eat.


Afterthought: The store-bought fudge wasn’t very exciting on it’s own, but in the ice cream, it was a complete disaster. It was rock-solid and hurt my mouth because the chunks were too big and edgy. Never doing that again.

Biscoff Speculoos Lotus cookies recipe and product review

Everyone in Israel knows these caramel cookies , and they can be found in all the convenience stores, but as I read American blogs, it seems these cookies are pretty rare on that side of the world.

Since I love making anything on my own, I’ve tried to find the secret to the Biscoff lotus speculoos cookies on the net, and when that didn’t work, I tried to recreate them from the ingredients.

I don’t know what the American product packaging looks like, but the Israeli one is actually very international and has the ingredients listed in about 10 different languages. I read the Hebrew, then the English, then the Italian, French, German and anything else that was there, and I realized that there was an inconsistency with one of the main ingredients. In English, it says brown sugar, while in a different language it said syrup, and in another language it said caramel.  Aha!

The cookies are called ‘caramel’ cookies, so it would make sense they should have caramel in them. And perhaps that caramel comes in the form of syrup. Aha! Now I just need to find a recipe that uses honey (because honey is like a syrup) and cinnamon, the other flavor ingredient of the famous cookies.

The Google search led me to this recipe, which I adapted and replaced the honey with caramel syrup.

Total Success!
I don’t have a picture of the cookies because we ate them all before I had a chance to photograph them. Either way, they just looked like very tan squares, nothing much until you bite into them.

Homemade Biscoff Speculoos Lotus cookies

For the caramel syrup:
1 cup granulate sugar
1/3 cup boiling water
For the cookies:
4 cups all-purpose flour
1 teaspoon baking soda
1 teaspoon cinnamon
1/2 teaspoon salt
2 sticks butter
1 cup granulated sugar
1/2 cup caramel syrup

In a heavy-bottomed pot, heat the sugar until it caramelizes. Don’t let it burn, just allow it to get a nice tan. Once all the sugar crystals have melted, take a 1/3 cup of boiling water, and from a distance, pour it quickly into the pot. The sugar will bubble and spit, and it will be dangerous to be close to the pot while it’s doing that. Wait for the bubbling to subside, and only after that begin to stir the pot to help the caramel dissolve in the water. this might take some time, and if you get tired, or don’t see any change, turn off the flame, cover the pot and let it sit that way over night. The caramel should have dissolved by morning. The end result you are looking for is a thick, honey-like syrup when it cools (while it’s hot, it will be very runny). If it’s too runny even when cooled, boil it a bit longer to evaporate some of the water.

You will use 1/2 of syrup for this recipe, and the rest awesome for many other things. I like to put it in warm milk, with a pinch of cinnamon, for a biscoff-flavored hot drink. It’s also great on oatmeal (with a pinch of cinnamon for a biscoff-flavored breakfast), ice cream, and anything you would normally use honey or chocolate syrup for.

Cream together butter, sugar and caramel syrup.

Gradually add in flour, baking soda, cinnamon and salt, and mix until well-combined. If the dough is crumbly, knead the dough just until combined, but don’t knead too much, or you’ll develop gluten and get a very tough cookie. If your syrup was too runny, the dough might be too sticky, so add a bit of flour.

Divide dough into four equal parts.

Roll the dough out between two sheets of parchment paper, to 1/4 inch thickness, and cut with a cookie or ravioli cutter.

Bake at 350ºF until just golden brown but still soft to the touch, about 12 minutes. Let the cookies cool in the pan, or they’ll crumble when you try to lift them. The cookie will harden as they cool.

And now to the product review.

Biscoff lotus cookies spread

Basically, it’s cookies ground up and mixed with saturated oils to form a spread.

Everyone who blogged about this has raved about this product, but I must say I’m a bit disappointed. Don’t get me wrong, this is good stuff and a great idea, but after such great cookies, and such great reviews, I was expecting a much more impressive burst of flavor.

It tastes like the caramel cookies, but is a bit milder, since the cookies have been diluted with oils to make the spread. Also, the oils leave an unpleasant aftertaste and oily feeling. Sadly, this is less than what I was hoping for.

Here are 2 uses for the spread:

And I’m sure you can find more, assuming you can find the spread.

I am mostly disappointed by this product because my homemade version of it is much better.

I have read about this spread about a year and a half ago on The Cupcake Project, but I never expected it to come to Israel. So at the time, I attempted to make my own version, with the help of a recipe from the Romanian cookbook ‘Sanda Marin’. This Romanian cooking bible, as my mother calls it, was written more than a century ago, and has been popular since. For good reason. 

Among many fantastic recipes, I found a recipe for making a spread out of cookies, for frosting a cake or anything you might use a spread for.

I adapted the already easy recipe to the modern kitchen.

Homemade Biscoff speculoons lotus spread

1/2 cup water
1/2 cup granulated sugar
300g cookies or cake of your choice
(the original recipe also suggested adding rum to taste)
Food processor

Make sugar syrup by boiling 1/2 cup water and 1/2 granulated sugar, until all the sugar dissolves.

In a food processor, grind the cookies (or cake. Or dried Challa or yeast cake) to a powder. Pour some of the sugar syrup on the cookie powder as you grind, until it forms a spread or dough. Depending on how dry the cookies/cake were to begin with, this will take a different amount of syrup. The spread might be a bit crunchy at first, but if you leave it for a day or two, the sugar crystals will dissolve and the spread will be much creamier.

You can spread it on anything, use it as frosting for cakes and cupcakes, use it like peanut butter on sandwichs or oatmeal, or just eat it with a spoon. A more complicated option is to add it to an ice cream batter and freeze, to make caramel cookies ice cream. If the dough you’ve made is pretty think and not so spreadable, try using it as you would marzipan- shape into balls and decorate, or roll out and decorate a cake with it like sugar dough.

And that reminds me, I want to review another product, one that is only sold in Israel as far as I know.


Almond Nuchella

No, not Nutella.

Nuchella. With a ‘ch’, so it would sound more Italian.

This is made by an Israeli company which specializes in almond products, mostly marzipan and almond butter.

When I bought this spread I thought it was going to be a somewhat healthier version of Nutella (mmm… Nutella). I just hoped it wasn’t going to be a cheap knock-off like others I’ve had the non-privilege to taste.

Well, it’s good. Really good.

It also has nothing to do with Nutella, and very little to do with health.

The spread is made mostly of almond butter, with a hint of bitter almond aroma, and some chocolate and hazelnuts thrown in. this doesn’t taste like Nutella at all, but it does taste very good.

Because of all the fats and sugars in this, I can’t bring myself to call it healthy, even if I did buy it at a health food store.

And it’s 4 times more expensive than Nuttela.

I do like the design of their label. It’s decorated with almond tree flowers. And so is their marzipan wrapper:

I hope you can see the similarity of these flowers to the Japanese Sakura. The almond and cherry trees belong to the same family, and their flowers are almost identical. The almond tree isn’t revered in Israel as much as the cherry trees are adored in Japan, but we also have an annual festival to celebrate the end of winter, and a big part of that is the flowering almond tree.

I like this company, and I like their products. All made in Israel.

Happy Independence Day!

haven’t posted in two years, because I was too busy with my research and various other things, like two dogs, a cat and finding love.


But today it’s Independence Day in Israel, which means we got a very long weekend, in which I got to play around the kitchen a bit, blog about it, and even get on with writing my thesis!

Independence Day in Israel is basically ‘national barbeque day’, but since my father broke his leg, he’s not too keen on the traditional ‘going out to a national park and grilling’, so we just had a nice family lunch at home.

I brought desert. A roll cake decorated withIsrael’s flag and filled with whipped cream and kiwi.

Does it look easy?

It actually was, once we managed to find a translation of the recipe from Japanese (1 hour), compare 4 sites that gave us 4 differed versions of it (1 hour), make one batch that completely failed (2 hours), figure out what went wrong (1/2 hour), get more eggs and a more suitable pan from Mom (1/2 hour) and start all over again (2 hours).

Now I can give you a very long post on how to make this cake, and others, without screwing up.

It’s really ease, I promise! You just need to read the instructions carefully before you start.

The original inventor of this concept is Junko

Someone scanned some of the recipes in here book. These come with drawings of the processes, to help you understand.

And here are three other sites, each with a recipe out of Junko’s book, each one a little different, which made it confusing to adapt to my design:

The final result of my quest is a sort of algorithm, that is less complicated than the original, which you can adapt to any design you like.

Prepare the pan:



On the parchment paper, draw the design you want to see on your cake. Remember that the center of the pan is the center of the top side of the finished roll. Also, remember that the design will be mirrored in the end result, so you have to draw the mirror image of what you want. That’s important for letters for example, but doesn’t matter for symmetrical symbols such as a Shield of David.

Place the parchment paper in your pan, so that the drawing is facing down, so the batter won’t touch the pencil markings.

Oil the sheet very lightly. I sprayed with olive oil spray, and since that wat the first time I used such a device, I sprayed too much.

If the paper is too oily, when you pipe your color, the oil will move and form pools of oil in the coloring batter. Absorb excesses oil with absorbent paper, until you have a very, very small amount of oil left. If you do this, the batter will be easy to spread.

 Ingredients for the batter:

4 large eggs at room temperature – Divided into 4 whites, and 3 yolks (1 yolk will not be used)
35g sugar
60 ml water
40ml vegetable oil
1/4 tsp vanilla extra
80g flour
more flour as needed (about 1/2 tsp for each color you use, but see instructions)
1 tsp corn starch
food coloring as needed


A brownie pan (a square pan, about 12X12 inches or 30X30cm)
Parchment paper
Pencil (not pen!)
Piping bags (or anything you can adapt to a piping bag)
Bowels, many bowels. 2 bowels+ as many colors as you use
Electric mixer
Wire rack

Instructions for batter:

Divide your eggs into 4 whites, and 3 yolks (1 yolk will not be used). Make sure the bowl that contains the whites does not have any oily residue or yolk in it, as that will prevent the white from foaming properly.

To the yolks, add35 gramsof sugar and beat on high speed, until the mixture has increased in volume, is very pale, and can hold it’s shape for a fraction of a second while you mix (about 5min of mixing).

To this you add 60ml of water, 40ml of oil, 1/4 tsp of vanilla extract and 80gr of flour. Continue mixing until the batter drops from the beaters in ribbons (about 1min).

Now clean your beaters very well with soapy water, and dry thoroughly. You will now use them to beat the egg white, so again they have to be clean of any oily residue.

Now beat the whites to soft peaks, add 1tsp corn starch and continue beating until the foam forms stiff peaks.

 For coloring:

Depending on how much of a certain color you require, take 1-4 teaspoons of yolk batter in to a separate bowl. For each teaspoon, add 1/2 teaspoon of flour and 2 tablespoons of egg-white foam. Mix the better in a folding motion. If the batter is too thin, now is the time to add more flour. The end result should be thick enough to drizzle from a teaspoon, so that it would be relatively easy to use for piping.

In my case, I needed a lot of blue, and added about 1tsp in addition to what the recipe said in order to get the right consistency, so I used 4 tsp of yolk batter, 3tsp of flour and 8 tbsp of foam.

Add a small amount of your desired food coloring, and mix. Adjust the coloring as needed. For example, I started with a little bit ofDalton’s Royal blue, then added more, and eventually added a little tiny bit ofDalton’s Violet to get the right color.

If you want to use nature food colorings, such as cacao or matcha tea powder, exchange part of the flour in the batter with these powders. For light brown use 1/4tsp flour + 1/4tsp cacao. For dark brown (almost black) use just cacao powder and no flour at all. Same goes for matcha.

The main batter:

Use the rest of the egg-white foam to fold in to the yolk batter. Fold and break the foam as you mix, until you get a very runny, fluffy, light colored batter. As fluffy and as light a little kitten. Look at her little face, she’s so sweet the tiny little baby, I love my little mini me, I will do all you command, oh tiny kitty… I wear the cheese, it does not wear me.

By the way, you can also color the main batter if you’d like.


Preheat the oven to 170deg Celsius.

Transfer all your different colored batters to piping bags. I used a sandwich bag and snipped off the tip.

You want to start your design by drawing the smallest parts and thinnest lines of the drawing, and then bake them for 1-2min, to help it set. The better should lose some of its shine.

If you have other colors to add, add them one at a time, baking for 1min between each color to help it set. If you don’t do this, the colors will just flow into each other and you’ll get a messy design.

In my case, I had only one color to worry about, so my boyfriend (who has a much steadier hand) traced the lines and I filled them in, first with the piping bag and then with a teaspoon. Then we baked for 2min, until the design lost some of its shine.

When you’re done with all the colors, put some of the main batter in a piping bag and go gently around your design. This batter is very runny, so it might not drop exactly around your design. That’s not a problem, because you’re going to cover everything with that batter later. The point of this is to fix your design in place before you pour all the main batter on top, and possibly ruining everything.

Bake again for 1 min, and only then (gently) pour the rest of the main batter on top of everything. Try to pour it in neutral territory, where there is no color, so that if the colors are not completely set, you will not cause them to flow. Spread it well in the pan. Now shake the pan a bit, and tap it on the bottom, or even drop it on the counter, in order to let out large bubbles. This should help the batter rise evenly in the oven.

Bake at 170deg Celsius for about 14min, or until the top is very slightly browned, and a toothpick inserted in the center comes out clean.

The fact that you added water to the yolk batter will help keep it from browning, so that the end result will be a colorful design on a white background. Don’t wait for it to brown, that is not an indicator of done-ness.


While the cake is in the oven, prepare a wire rack covered with another piece of baking paper. Immediately after the cake is done baking, flip it onto the rack and gently peel the baking paper from the design. Don’t let it cool before removing the paper or it will tear the design.

Keep the cake on the rack to cool, and cover it with a towel or the original baking paper, so it won’t dry out.

Once it’s completely cool, turn it over once again, and peel of the baking paper that was on the bottom. It will tear the cake a bit, but that is the inner side, so no one will see it any way.

If needed, cut of the edges of the cake, to make it more attractive.

While the cake is cooling, you can prepare the filling.

Ingredients for filling:

10g sugar
20ml hot water
1/2 tbsp Grand Marnier (or any other flavoring, optional)

whipped cream
150ml whipping cream, cold from the fridge
14g sugar
A few drops vanilla essence (optional)
Soft fruit of choice cut into small pieces (strawberries, kiwi, banana, peach… we used 2 kiwi fruits)

Instructions for Filling:

Mix the sugar, hot water and liquor in a cup, until all the sugar dissolves.

Whip the whipping cream with the sugar. You can also add some vanilla essence, if you don’t like the taste of cream.

Slice the fruit.

Now you’re supposed to add things in the following order: syrup, whipped cream, fruit.

(By this stage I was getting tired and I completely forgot to put the syrup. Luckily, I remembered before it was too late, and in the top left picture you see me scraping the whipped cream off the cake, so that I can put the syrup on.)

After the cake has cooled, Cut VERY SHALLOW cuts into the cake about2 cmapart all the way down the cake. (This might help with the rolling later. I didn’t read the instructions properly, and I cut a criss-cross pattern on the cake. I don’t know if it matters.)

Now use a pastry brush or teaspoon to brush/pour the syrup on the cake. Make sure everything is covered with syrup.

After that, spread the whipped cream evenly on the entire surface.

Arrange the sliced fruit in three rows on the whipped cream, parallel to the direction in which you are about to roll.

Try holding the cake with the paper it’s on, lift and make one loose roll. This should not form a spiral pattern, because the dough will break if you try (guess what I did?)

Wrap the cake with the paper, and twist the ends like a candy.

Let it cool in the fridge for at least 1/2 hour before serving.

This is my dad, proudly holding the cake.

This was a badly rolled cake. You can see that a part of the dough broke, and a piece of kiwi is completely out of the cake.

But it was sooooo gooood! Light and fluffy, not too sweet, perfect ending for a heavy meal.

If you care about Kashrus, the batter is completely Parve, and you can make a non-dairy filling if you’d like. You can always fill it with jam, a nut filling of some sort, coconut cream-based vanilla cream, or anything really.

Do not use Parve whipping cream. Ever. It’s nasty stuff, tastes like shaving cream.

Cookie Dough Fudge Mint Chip, 2.2

Chocolate ice cream with mint patties and raw cookie dough.

Not bad at all, but not what I had in mind.

I love the mint patties!
Problem is I put too many of them and they kinda took over.
The cookie dough was just too mild between all the chocolate and mint, so it didn’t add anything to the flavor. It gave some crunchy texture because of the un-dissolved sugar crystals, which could be good or bad, depending on your own preferences.
The chocolate ice cream was very chocolaty, but it wasn’t fudgy. It had some powdery feeling because it was made with cocoa powder and not chocolate, wasn’t smooth and creamy as I would expect from fudge. It is a great chocolate ice cream, but it’s not fudge ice cream. Maybe I’ll try a different recipe for it next time.

Here is what I’ve done:
1/3 recipe raw cookie dough
150gr mint patties, chopped in to quarters (should have used just 100gr)
1 cup milk
1 egg
200gr sugar (150gr might have been better, more ‘dark chocolaty’)
80gr cocoa powder
2 cups heavy cream
Whisk the together the milk, egg and sugar, and heat over a low flame until a thing custard forms. Remove from the heat and stir in the cocoa powder until well combined. Let cool and add the cream.
Cool in the fridge over night (and freeze the ice cream maker bowl).
Freeze ice cream according to ice cream maker instructions, adding the cookie dough and mint patties after it’s done.

Cookie Dough Fudge Mint Chip, 2.0

So here we are again, making CDFMC ice cream. This time, it a chocolaty-fudgy ice cream, with bits of cookie dough and chocolate covered mint patties. I should be using mint flavored chips, but those are not available where I live.
Ignoring that minor peeve, the science of ice cream today is about the cream itself, milk, ice, and emulsions.
Lets start with a basic quaestion:

Water and oil don’t mix. Why?
Usually, different substances don’t mix because the bonds between similar molecules are stronger than the bonds between different molecules.
That’s Enthalpy. However, with water and oil, the reason is Entropy, the desire of a system to have as much disorder as possible. You would think that mixing would create more disorder, but that requires a lot of space, so that the molecules could avoid each other, like in the gas phase. In a liquid it’s different- the molecules are too close together and they can affect each other.
A water molecule has 6 different ways for hydrogen bonding with two other water molecules. Replacing one of those molecules with one that cannot form hydrogen bonds reduces the potential conformations by half, limiting the movement of the molecules and forcing a higher degree of order on the system. A higher degree of order requires a greater amount of energy to maintain, and therefore is not a favorable situation.
If oil molecules stay together, apart from water molecules, they reduce their exposure to the water and reduce the entropy loss.
The hydrophobic effect is entropy driven, and the attraction of the water molecules to each other is only a secondary force. It has nothing to do with the way water dissolves polar molecules, such as table salt.
If you can reduce the order of the system, or input a lot of energy, you could force the oil and water to mix. For example, you could boil a lot of water, with a tiny bit of oil, and eventually they’ll mix.
You could also use other molecules as barriers, which will reduce the contact area between water and oil, but at the same time allow them to mix together. That is what emulsifiers do.

What are emulsifiers?
Molecules with a dual nature, just like soaps and detergents.
Their dual nature allows them to remain in the interface between water and oil, and to help form and stabilize bubbles of one liquid within another.
The emulsifiers in milk and other emulsions are found in very small quantities, and they cover the bubbles only partially, so their stabilizing effect is not complete.
Emulsifiers can be soaps and detergents, but they can also be large molecules such as proteins and complex sugars, which is the case with milk and beer (in beer they stabilize gas bubbles, remember?).
Because emulsifiers play only a small (but important) part in stabilizing the emulsions, the emulsion’s own attributes become more prominent.

Milk is an emulsion of oil in water
The oil in milk is broken up in to very small bubbles, on the scale of 100nm, which is also the scale of wavelength of visible light. Bubbles that small are somewhat stable and it takes them a while to combine together and form a single layer of fat. The other thing they do, is break the path of the light that goes through them, separate it to its components (red light, blue…) and make a mess of it, so instead of two transparent liquids, we see one white liquid.
Milk straight from the cow isn’t that stable, and it will separate in a few days, because the bubbles are of un-even size and larger than the store-bought milk. The milk we buy at the store has gone through a lot of to become stable for more than a couple of days.
It is heated and pasteurized to prevent it from fermenting into yogurt or cheese.
It is separated into a water layer and a fat layer, along with anything that is soluble in those layers. Then the fat is returned in to the water layer at a specific and predetermined percentage, so that each carton of milk will have the same amount of fat and calories in it. And then the milk goes through a homogenizing machine, which forces the oil bubbles to break into much smaller bubbles, all the same size. The bubbles remain that way for a certain period of time due to the natural emulsifiers found in milk.

Size, and the degree of variation, matters
A long time ago, there lived a man named George Gabriel Stoke. His contribution to today’s post is Stoke’s Law, which is a mathematical representation of the forces that affect a solid round object, as it sinks to the bottom of a vessel, through a liquid. This physical law can be converted and applied to liquid systems, to represent how round blobs of oil behave in a water environment (or vice versa).
According to this law, there are 4 things we need to consider:
The difference of densities between the oil and the water.
The difference in the viscosity of the two liquids.
The size of the bubbles.
The degree of variation in the size of the bubbles.
These four parameters affect the Brownian motion (random motion), the gravitational pull on the bubbles and the contact-induced motion of the bubbles. The gravitational motion is the most prominent of these.
The mathematical representation of the law implies that the bubbles should be as small as possible and as uniform as possible, in order to prevent them from concentrating at the bottom. Also, the emulsion shouldn’t be kept in large and tall containers, but rather in small, short ones.
The purpose of this is to reduce the gravitational pull on the bubbles, and their chances of bumping and connecting.

What are we trying to prevent?
When bubbles meet, there are four processes which might take place:
Creaming or sedimentation- depending on the difference of densities between the water and the oil, the bubbles either float up (creaming) or sink down (sedimentation) in the fluid. The problem is the same- all the bubbles of a certain substance become concentrated in a single place. This process is reversible- all you have to do is shake or stir the container to redistribute the bubbles.
Flocculation- bubbles touch and stick to each other, to form clusters. The clusters can be forced to disperse by using a great deal of force and energy and homogenizing the emulsion once more.
The clustering is caused by the emulsifier molecules, which are very long. They can partially detach themselves from one bubble and attach themselves to another bubble, thus linking the bubbles together.
A different option is that the emulsifier tails on one bubble entangle themselves with the tails of other emulsifiers on the other bubble.
Coalition- if the bubbles are close enough together, and the partial coverage of the emulsifiers allows for uncovered patches on the surface of bubbles, the bubbles may combine to one larger bubble.
To prevent coalition, you can increase the amount of emulsifier, but that costs money, and might result in flocculation. Or you can use an ionic emulsifier, so that the charge on the bubbles will repel them from each other. The problem with using an ionic emulsifier (detergent) is that it may not be enough to stabilize the formation of bubbles to begin with. It’s very difficult to find the right combination of emulsifier characteristics needed for a certain emulsion.
Phase separation- the final result of the previous processes is phase separation, when all the bubbles have gathered in one location, clustered together and combined to form one larger bubble, until just a single bubble is formed- the phase that is separate from the surrounding solvent.
The larger the bubbles are, and the greater their size distribution is, they will cream and flocculate faster. That’s why it’s very important to use the right emulsifier, at the right amount, and also to force the bubbles into small, evenly sized bubbles (homogenize the emulsion).
Milk is not the only food emulsion around. Margarine is an emulsion of water in oil, which uses the fat itself as an emulsifier (tiny globules of fat cover the face of the water bubble and protect it. The coverage and emulsification is physical, not chemical). Mayonnaise is an emulsion of water in oil, where proteins and other molecules in the egg yolk act as emulsifiers between the oil and lemon juice. When making salad dressing from oil and lemon juice, the citric acid in lemon juice acts as an emulsifier.
Making all these emulsions requires the energy of stirring, because the emulsifiers alone are not enough. Using greater amount of emulsifier, or using more efficient emulsifiers, will reduce the amount of stirring needed, up to a point where the presence of the emulsifier would be enough to create an emulsion. That is a special case, known as micellization and micro-emulsions, which lead to liquid crystals- a vast and interesting field, which I might post about some other time.

Ostwald ripening and icicles in your ice cream
A more in depth explanation of flocculation and coalition is Ostwald ripening. This is a process in which the growth of a large cluster is more thermodynamically favored than the separation of that cluster to its smaller components. On the other hand, a small cluster has better chances of disintegrating than growing.
Statistically speaking, a cluster with two monomers has a great chance of disintegrating- just one monomer needs to leave in order to destroy the cluster. A large cluster, of one thousand monomers, has a much smaller chance of disintegrating, because 999 monomers need to leave. It has a much greater chance of growing.
Energetically speaking, the molecules on the surface of a cluster are less stable than the ones hidden in the interior. The greater the ratio of surface to volume, the less stable is the cluster. Larger clusters have a smaller ration and therefore are more stable.
If you let your ice cream out of the freezer to defrost just a little, small icicles will start to form. Even after you return it to the freezer, those clusters will continue to grow, and your ice cream will become gritty and unpleasant to eat.
Home made ice cream is more susceptible to this process, because the mass produced ice cream has the benefit of powerful homogenizing machines, and special emulsifiers, to give it a good start.
The home made ice cream is mostly based on the emulsifying qualities of eggs, which is why a custard-based ice cream is much creamier than a non-custard ice cream.
Your ice cream maker is your homogenizing machine, and the more efficient it is, the creamier your ice cream will be, even without eggs.
The problems start when you’re trying to make a sugar syrup-based sorbet, without an ice cream maker. No emulsifiers and no homogenization. Bad idea.

My new recipe, with pictures, in the next post.