Episode 12: Masala Chai

from Don the Apron

from Don the Apron

I love a hard-worn list. My favorite is the list you keep adding to, that chronicles your ambitions and actions and tells you the kind of person you are. You need two columns: a To-Do on the left and an italicized Done on the right. The best are the horizontal black lines bisecting items well finished, the copy-and-paste shift from left to right on an Excel sheet. Do you ever write down tasks you’ve already completed just to strike them out? I confess I’ve done that, on bad days, when I feel I’m not getting enough things done. I need that mental kick-start to tackle bigger items abandoned on the left.

Making chai has been on the left for weeks. Not because it’s difficult – it’s actually extremely easy. But I had been craving a very specific chai, the kind my grandmother used to make in New Delhi – sweet, fragrant, spicy, sinus clearing, that harks back to sticky heat and loud fans and cotton quilts. I needed green cardamom pods, not available whole at Whole Foods. Finally I resorted to Amazon Prime. Two days later, I was ready.

Science:

All teas come from the Camellia sinensis plant, a sub-tropical evergreen native to Asia. The plant grows the best in loose, deep soil, and at high altitudes.

Leaves are plucked and laid out to wilt for several hours to soften. Then they are rolled, pressed and twisted to break open the cell walls. Enzymes and essential oils are exposed to oxygen, which turns leaves reddish-brown and changes their chemical composition, creating new and complex flavors. Leaves are then dried out completely to end the oxidation process, and packaged for consumption.

Smashed green cardamom, cloves, black peppercorn, cinnamon

Smashed green cardamom, cloves, black peppercorn, cinnamon

History:

We can largely blame the existence of Indian tea culture on the British. Tea grew in Assam for centuries, but it was drunk only as medicine.

In the early 1800s, the British East India Company schemed up a plan to develop tea in India to displace China’s monopoly on tea production and feed British demand. The BEIC had been commissioned by the English Queen to pursue trade with the Orient, rising to account for half of the world’s trade and dominating in commodities such as cotton, silk, salt, and opium. The Company also ruled India at the beginning of the British Empire.

In the 1820s, the BEIC took Assam from local rulers and through indentured servitude began tea production. Fifty years later, Assam surpassed China in tea production. Yet consumption within India remained thin until the India Tea Association (British-run) promoted and subsidized tea breaks at factories, mills and mines. Eventually tea became an addiction, and local chaiwallas, or streetside tea vendors, set up and added spices and more milk and sugar to appeal to an Indian palate. Today India is the second largest tea producer, noted for its Assam and Darjeeling strains, and Indians drink half of a cup daily on average. India’s current Prime Minister Narenda Modi is a former chaiwalla who served tea outside his father’s grocery stores.

There are many variations of tea in India depending on region. In Hindi-speaking north India where my family is from, masala chai is very popular.

Recipe:

Bring whole milk and water to a boil with green cardamom, fresh ginger, black peppercorns, and cinnamon. Don’t use more than a tablespoon of spices for two cups – you may regret it. Let simmer on low heat for 10 minutes. Add loose tea or tea bags and bring to a boil, then let simmer again for 5 minutes. Add a few sugar lumps – don’t you dare add Splenda. Strain and serve yourself in your favorite mug.

In India, we’d have it with buffalo milk.

milk

Episode 11: Bagels and Lox.

Belly Lox, saltier, fattier, no smoke - the way lox was made in the olden days.

Belly Lox, saltier, fattier, no smoke – how lox was made in the olden days. Courtesy of Russ and Daughters

Bagel and lox platters with tomato, onion, and cream cheese, orange juice on the side. It hits on all cylinders of my family’s palate – salty, pungent, umami, hearty, kick-starting a Sunday morning nap. I always ate my sandwich too fast, and looked on wistfully as my family laughed around the table and went on passing plates.

Quick definitions to start:

Smoked Salmon: any kind of salmon, first cured and then either hot-smoked or cold-smoked.

Lox: salmon cured in a salt-sugar rub or brine and never cooked or smoked, so it has a silky rich texture and translucency.

Curing: any method of meat preservation. It can be salting, brining, aging, drying, smoking, or canning. The goal is to prevent the growth of microorganisms that will make you sick if you eat them.

Cold-smoking: slow exposure to smoke in an 80 degrees environment for several hours. Cold-smoked products are held in an unheated chamber through which smoke is pumped. Fish doe not get cooked but stays moist and silky. Only food that is professionally made and has been cured in some way should be cold-smoked, since between 40-140 degrees microbes can reproduce rapidly.

Hot-smoking: smoking fish in the same chamber as the burning wood, thus cooking the fish, resulting in a flaky texture and smoky flavor

Nova lox: made from salmon hailing from Nova Scotia, that has been cured and then, as an exception to the rule, cold-smoked. This is what you’re probably getting when you order a bagel with lox – but it’s not actually lox – it’s smoked salmon.

Gravlax: Scandinavian preparation of lox, where lots of fresh dill and spices like juniper berries and pepper, and sometimes liquid, are added to the curing process. Not smoked!

Science:

We shouldn’t forget that lox is raw fish. Thankfully, my favorite condiment can also save us from bacterial infection. Salt is important in the curing process. In a dry rub or wet brine, salt draws the moisture out of microbial cells by osmosis, due to the higher concentration of salt outside the cell. When a cell is immersed in a solution with a greater concentration of solutes than inside the cell, the tendency is for water to flow out of the cell to balance the concentration of solutes. A cell cannot survive without water. Salmonella is inhibited by salt concentrations as low as 3%, staphylococcus requires 20% to kill.

Smoking meat additionally helps prevent spoilage by helping seal the outer layer of food, making it more difficult for bacteria to enter or for air to cause rancidity in fats.

History:

Salting is one of the oldest methods of food preservation and remained the primary method until the advent of the refrigerator in the early 10th century. The earliest recording of salt preservation was found in Egyptian tombs dating to before 2000 B.C.

Eastern European Jews married lox to the bagel in early 20th century New York City. They most likely learned the practice of fish curing in medieval Germany and carried that knowledge with them eastward during a middle Ages migration. Fish was popular among Jews, for it could be eaten with meat or with dairy. In the late 1800s they migrated to the United States and set up fish-smoking shops along the East Coast.

Bagels most likely originated among Ashkenazi Jewish communities in Poland in the early 1600s. The ringed bread was given to women during childbirth. Eastern European Jewish immigrants brought the bagel to America as well.

Unlike in Europe, in the United States salmon was plentiful. Captured in the Pacific Northwest, packed in barrels of salt and shipped via the Transcontinental Railroad to the East Coast, salmon, or its German word lachs, piqued the taste buds of Jews who had a strong affinity for cured and smoked fish.

Lox was easy to keep because it did not require refrigeration. Home refrigeration was available starting in the mid 1920’s but new immigrant families could not yet afford such an appliance. With refrigerators, heavy salt preservation was no longer necessary and was replaced with a shorter brine period.

The bagel and lox combo became institutionalized in the 1950s, thanks to New York delis.

Courtesy of a Russ and Daughters fan

Nova lox. Courtesy of Russ and Daughters

http://forward.com/articles/7669/the-raw-truth-about-lox/

http://www.smithsonianmag.com/smart-news/bagels-and-lox-are-a-uniquely-american-creation-578/?no-ist

http://www.npr.org/sections/thesalt/2013/09/21/224531885/no-schmear-job-at-last-a-history-of-bagels-and-lox

http://meatpaper.com/wordpress/2012/07/a-fish-and-bread-journey-the-natural-and-social-history-of-bagels-and-lox/

Episode 10: Olive Oil Cake.

cake with slice

Orange Olive Oil Cake

History:

Olive oil is as old as human civilization. That’s some fruit for thought.

Native to the Mediterranean, olives have been cultivated for edible use for five to six thousand years. Prehistoric humans plucked grinded the fruit and used the oil in cooking and in lamps. Its leafy branches were offered to gods and were used to crown the winners of wars and games, symbolic of peace. Its ancient greek name elaia gave us the word oil.

slice

Science: 

Olives themselves are unpalatable due to their bitter phelonin content. They must be soaked in an alkaline solution that can break down the bitter substances and the waxy outer layer, making the fruit more permeable to a subsequent salt brine and fermentation process.

Ninety percent of olive production is intended for olive oil. When the fruits are mature, around six to eight months old, they begin to turn from green to purple. They are coarsely crushed and ground into a paste to free their oil. The paste is squeezed to extract both oil and water from the solids. Additional oil can be extracted by pressing repeatedly and by heating the paste. The first press, the cold press, is the most delicate and stable and most likely to produce extra virgin oil.

The most precious olive oil is unrefined and sold right after harvest, for delicate flavoring and less for cooking.

Olive oil quality is judged by flavor and content of free fatty acids – that should be bound up in intact oil molecules. Extra virgin must have less than 0.8% fatty free acids. In the united states, quality labeling is not regulated.

The oil is green gold from chlorophyll and carotenoid pigments, and it contains phenolic compounds and aromatics from volatile molecules generated from the grinding process. Green smelling fragments of fatty acids call to memory herbs, apples and artichokes.

cake slice diagonal

Episode 9: Granola.

Rolled oats, sesame seeds, almonds, seasoned with lemon zest and brown sugar, heading into the oven

Rolled oats, sesame seeds, and almonds, seasoned with lemon zest, cinnamon and brown sugar, heading into the oven

History:

I rediscovered granola as a good source of carbs and proteins in my quest to snack healthy and evade the candy jar at work. I have resolved to make nutritious versions only.

Fittingly, granola was invented in 1863 by Dr. James Jackson of the Jackson Sanitarium in NY in an attempt to steer Americans away from their cholesterol-laden, meaty breakfasts. The first granola, dubbed “Granula”, was made from bran-heavy Graham flour, rolled into sheets, twice-baked, and crumbled into pieces that had to be soaked in milk overnight before eating. Thankfully for all of us, granula has been through much iteration since.

Ten or so years later, John Kellogg of the Kellogg Company started producing his own granula made out of oats instead of graham flour. He was promptly sued by Jackson and thus renamed his version granola. Other brands sprung up, and granola was a popular until the 1950s when sugared cereals like Corn Pops, Frosted Flakes, and Cocoa Krispies knocked it off on the grocery shelves. In the 1960s fruits and nuts were added to granola to promote it as a health food and popularize it among counter-culture activists and hippies, hence their nickname “granola heads.”

Granola went mainstream again in the 1970s. The first corporate granola “Heartland Natural Cereal” was invented by Jim Matson, an executive at Pet Incorporated of Saint Louis. Quakers, Kellogs and General Mills all introduced their own granola in the next two years. However, nutrition-wise these were just as bad as the sugared cereals, if not worse. Packed with high-fat and high-sugar ingredients, granola these days has a crispy slick and heart-racing sugary buzz. Don’t buy it! I insist that you make your own and save yourself from the stomachache later.

2

Science:

Granola is none too complicated. You start with your base (oats), add some nuts, add some seeds, sugar, salt, fat, and throw it in the oven. Afterwards, you can top with chocolate or dried fruits if you like.

One process is of note here though. The Maillard Reaction causes a browning on meats, seafood, and protein laden foods like nuts. It rearranges amino acids and certain simple sugars, which then rearrange themselves in rings that reflect light as to appear brown. Additionally, it produces characteristic smells of roasting, baking and frying. The amino acid molecules and sugars keep reacting in many ways, generating flavor molecules. In order for the reaction to take place, the temperature should be around 330 degrees, or above the boiling point of water. Hence, very wet foods or wet methods of cooking (poaching, boiling, etc) will not result in browning. The nuts undergo the reaction in the oven, coming out more toasty and nutty.

A greek yogurt and fruit accompaniment, or worthy on its own with milk

A greek yogurt and fruit accompaniment, also worthy on its own with milk

Episode Eight: Quiche.  

Quiche has been condemned as kitsch by the gourmet community after the decade of clunky hors d’oeuvres, shag carpets and disco parties. These days, it remains largely shunned or it sneaks its way into print under an alias of “savory tarts”. In my opinion, there’s really no reason for these disguises. When made correctly, quiche is the most elegant and sophisticated of eggy dishes.

History:

Quiche was born in Lothringen, a medieval Germany city later acquired and renamed Lorraine by the French. The word quiche derives from ‘kuchen’, the German word for cake. However, the original quiche Lorraine was in fact a pie containing egg and cream custard with smoked bacon. (Cheese was added a bit later.) The bottom crust was first made out of chewy bread dough but it has since evolved into a delicate shortbread crust–which we are experts on of course (see episode 7)–or a simple pie crust. Legend has it that in 1399, a saffron and honey quiche was served at King Henry IV’s coronation. King Henry IV is fascinating by the way – he deposed his childhood playmate King Richard II and let him starve to death in prison and then spent most of his reign quelling rebellions and assassination attempts. I love the Middle Ages. Anyways, the word word ‘quiche’ first appeared in print in a French cookbook in the early 19th century. Quiche reached America in the 1950s and gained widespread popularity in the 1970s due to its versatility and savory and sweet applications. DSC_0680

Science:

Eggs serve innumerable roles in baking. The water in eggs (88% of the egg white) moistens starches, and converts into steam and helps leaven baked goods. Egg whites can trap air bubbles, creating basis for soufflés (see episode 2!). Importantly for quiches, the egg protein albumin coagulates in heat, which causes amino acid chains to unwind and exposes hydrophobic molecules to water. These lil’ phobes quickly bond to other phobes outside their original amino acid chains to avoid water. This forms a solid, interconnected mass that traps milk and cream into a soft gel. Thus, a custard. Custard is simply any liquid that has been thickened by eggs. Careful though, if you heat albumin too fast, the hydrophobic molecules will clump together and separate themselves from the liquid, forming curdled lumps. You get scrambled eggs in your cream and it is heartbreaking, trust me. Thankfully quiches are pretty simple – just pour your eggs into a pie and stick it in the oven and it should turn out great. DSC_0706

Links:

https://themolecularcircus.wordpress.com/2013/02/06/kitchen-science-the-molecular-magic-of-custard/ http://www.foodreference.com/html/artquiche.html

Episode Seven: Shortbread.

IMG_5111

Today I made chocolate chip cookies that broke into a hundred little pieces when I touched them with my spatula. If someone thinks they know why this happened, email me!

On the bright side, the lemon bars I made on Thursday were excellent. The best part was definitely the shortbread crust.

History

Shortbread is a lovely old Scottish invention originating out of rusk, a 12th century medieval biscuit flavored with spices and sugar. The yeast used to make rusk was replaced with expensive butter, and shortbread became a special treat consumed only on Christmas and Hogmanay (New Year’s Eve). Queen Mary popularized this biscuit in the 16th century serving it to her royal visitors. I like to imagine her eating shortbread sliced into crumbly wedges flavored with caraway seeds, looking out her window onto green pastures where peasants toiled away.

The first printed recipe of shortbread dates back to 1736. There are several regional varieties – shortbread can include coriander and caraway, orange peel and almonds, and ginger depending on where you are in the UK. The shortbread is made in circular molds, finger shapes, or wedges called petticoat tails.

Science

Shortbread follows a very simple ratio: 1 part sugar, 2 parts butter, 3 parts flour. No leavening agent, no shortening, no eggs, no oil.

Compared to other cookies, shortbread has a high ratio of butter to other ingredients. Butteriness is a crucial quality for shortbread; in fact in 1921 the British government legislated that for a product to be called shortbread it must get at least 51% of its fat from real butter. The term short itself means crumbly, hence why the fat added to pastries is called shortening.

Why does butter make for crumbly pastry? Well, proteins in wheat flour form gluten when combined with water. As you knead the dough, gluten forms into a mesh that gives baked goods their structure, and becomes more and more stretchy, filling with gas bubbles from leaveners. Gluten is what creates allows for those air bubbles in your baguette, creating chewiness. In shortbread, we want to minimize gluten formation. The butter physically interrupts gluten formation and is a major tenderizer.

Shortbread is traditionally baked at a low temperature to avoid browning. However I like a little bit of browning. Because the sugars caramelize and the Maillard reaction takes place, which creates a large number of yummy flavors.

http://www.thenibble.com/reviews/main/cookies/cookies2/history-of-shortbread.asp

http://www.historic-uk.com/HistoryUK/HistoryofScotland/Scottish-Shortbread/

https://britishfoodhistory.wordpress.com/2012/06/10/shortbread/

http://www.saveur.com/article/Kitchen/Sweetly-Scottish

Lemon bars (recipe from Joy of Baking)

Shortbread crust:

113 grams (1 stick) of unsalted butter at room temperature

30 grams (about ¼ cup) confectioners’ sugar

130 grams (1 cup) all-purpose flour

1/8 tsp salt

Lemon Filling:

200 grams (1 cup) granulated white sugar

*Why is 1 cup of flour only 130 grams, vs. 200 grams of sugar? It’s because you are traditionally supposed to sift your flour before you measure it. Use a scale.

2 large eggs

1/3 cup of fresh lemon juice (about 2 large lemons)

5 grams (1 tablespoon) grated lemon zest

25 grams (2 tablespoons) all purpose flour

Garnish:

Powdered sugar

Lemon zest

Instructions: Preheat oven to 350 degrees F and place oven rack in center of oven. Butter an 8 inch by 8 inch pan.

Shortbread crust: Beat your butter and sugar together until light and fluffy. Add the flour and the salt and beat until the dough starts to come together. Press the dough onto the bottom of your pan and bake for 18 – 20 minutes, or until lightly brown on the edges. Remove from oven and let cool.

Lemon filling: Beat the sugar and eggs until nice and smooth. Add the lemon juice and zest, and stir to combine. Fold in the flour. Pour the filling over the crust and bake for 17 – 20 minutes, or until the filling has set. Remove from oven and let cool.

Cut into squares and dust with powdered sugar. Go to town!

http://www.joyofbaking.com/LemonBars.html#ixzz3UrYgSKmL

Episode Six: Cocoa Powder.

Episode 7: Cocoa Powder and Crumbly Cookies

IMG_5031

I made a mistake today guys. I winged it on a cookie recipe; I swung and I missed! Okay, these cookies were still pretty tasty. They were crispy and salty-sweet, a thin under-baked brownie layer surrounded by a crunchy exterior. But they’re not what I crave – the soft, yet structural behemoths studded with chocolate chunks, the Costco cookie.

Here’s what happened: I followed Alton Brown’s chocolate chip cookie recipe to the last gram!

…then I added 60 grams of unsweetened natural cocoa powder, about ¾ of a cup.

History

In 1828, Dutchman Conrad Van Houten sought to invent a less oily version of hot chocolate. He developed a screw press that removed most of the cocoa butter from roasted ground beans, leaving a defatted chocolatey cocoa powder remaining. The Swiss added milk powder to his invention to reduce astringency and smooth it all out. Voila! Cocoa powder was born.

Science

Cocoa powder is mostly carbohydrates and proteins with a few minerals like calcium, copper and magnesium thrown in. Because it has been defatted, cocoa powder acts like flour in recipes and makes cookies crumblier and drier. A decent rule of thumb is to only add up to one part cocoa powder for four parts of flour. My recipe called for 300 grams of flour, so adding 60 grams of cocoa would have been okay if I had reduced the flour content. I should have done 60 grams cocoa, 240 grams flour.

Additionally, the more cocoa you add, the more sugar (a wet ingredient) and moisture you need! Cocoa powder acts like a sponge, sucking up moisture. That’s why my cookies were surprisingly salty. If you add more than a couple of tablespoons of cocoa powder you’ll need to add more liquid too.

Some more fun facts

After the press, cocoa powder remains coated with a thin layer of butter, and its fat content will range from 8 to 26%. Natural cocoa powder has a strong flavor, astringency and bitterness. Its pH is 5.

Dutched or alkalized cocoa describes cocoa beans treated with potassium carbonate which raises its pH to a neutral 7 or alkaline 8. It adds an alkaline taste (ever tasted baking soda?) and reduces bitter phenolics and roasty caramel molecules, forming a milder flavor and darker color.

Some recipes rely on acidic natural cocoa to react with baking soda and cause leavening via carbon dioxide. Because alkalized cocoa is neutral it will not react with baking soda (another alkali) so it must be used with acidic baking powder.

http://www.seriouseats.com/2012/10/ask-the-food-lab-on-hot-chocolate-and-whole-wheat.htmlHarold mgee’s bookAlton brown’s book

:http://www.joyofbaking.com/cocoa.html#ixzz3Twk3aFSK

Episode Five: Muffins.

DSC_0673

Baking frustrates me. I follow a recipe; I use the right ingredients in slightly different proportions and mix them a little bit differently than instructed, and my goods look completely different from the picture.

The difference between muffins and cupcakes epitomize this perplexity. Same ingredients stirred together and baked, yet the results are not the same. Structurally, what’s causing this difference?

Muffin Method

The Muffin Method produces an uneven, soft texture in muffins, breads and pancakes.

You simply need to combine dry ingredients (flour, leavening, salt, spices). Then, combine liquid ingredients (oil, milk, water, eggs, sugar – because it melts so fast). Add the two together; stir until barely combined. Bake it up!

Unlike creaming, when you combine the wets and the drys you are not creating seed air bubbles. Thus, leavening induces the only air bubbles, which are randomly sized and create an uneven texture.

Second, muffins contain much less sugar than cupcakes, which means their texture is much less tender.

WHY?

In addition to sweetness, sugar creates tenderness in baked goods. Sugar gets in between proteins and steals water, slowing down coagulation. Heat breaks down the molecular bonds of proteins, causing proteins to bond with their neighbors, causing coagulation, or thickening, forming the structure of the baked goods.

Watch out for overmixing your batter. Sift drys first. It aerates the flour, increasing the volume, allowing for easier integration into a batter. Less stirring means less gluten is formed, which creates a more tender muffin.

Creaming Method

The sugar crystals cut into the fat, creating air bubbles that the fat seals over. These are seed bubbles. The bubbles are evenly dispersed throughout the fat and there is an even rise in the cake. The air assists in leavening. The sugar itself is suspended in the fat. This method makes cake batter or cookie dough. The air expands in the oven, serving as a leavening agent.

Alton Brown’s I’m Just Here For More Food was a crucial source of information for this piece.

Episode Four: Cheese.

You couldn’t stop me at yogurt. Dairy is the most magical of all grocery store staples.

History:

It’s quite difficult to summarize the intricate and varietal histories of cheese making in a few short paragraphs, but for the sake of everyone’s attention span including my own, I will try.

Cheese has been made since before history has been written down. Nobody knows exactly when or where it started, but there is evidence of cheese-making in Northern Europe around 6,000 BC, in the Sahara Desert around 4,000 BC, and in Egypt in 2,000 BC, as illustrated by Egyptian tomb murals. In Ancient Crete, tablets document cheese inventories. Thus, cheese was most likely not invented in one place but rather discovered in many places. Animal stomachs, which naturally contain the acidic enzyme rennet that turns milk into curds and whey, were often used to store milk and probably naturally curdled milk over time.

By the age of the Roman Empire, cheese was both an art and a large-scale enterprise. Cheese spread (ha!) over the next several centuries to Northern Europe, where less salt was needed as preservative in a cooler climate. The Middle Ages were quite fruitful for cheese invention. Cheddar emerged in the 16th century, Parmesan in the next, Gouda in the one after that. Cheese came to the New World during colonization.

Jesse Williams, a New York dairy farmer, is credited with the invention of assembly line cheese in 1851. In the 1860s scientists learned how to mass-produce rennet, which caused a new era of industrial cheese production. By 1880, there were four thousand dairy factories in the United States. Factory made cheese surpassed traditional cheese consumption in WWII era. Cheese processing began to involve emulsifiers, stabilizers, flavoring and colorings.

Today, over one-third of milk produced in the US becomes cheese.

Science:

Cheese is a method of preserving the nutrition of milk, and it consists of many steps. Fermentation, coagulation, dehydration, and salt preservation are the main ones.

First things first, pasteurize your milk! Milk is heated up to 185 degrees Fahrenheit to kill off uncontrollable bacteria. Bacteria are then carefully added back in, and begin to convert lactose to lactic acid via fermentation, that funky process we went over in Episode 3.

Then, milk is coagulated by rennin, an enzyme found in the bellies of ruminants (animals that chew and chew and chew grass) that curdles milk, prolongs its digestion and facilitates better absorption. Rennin can also be extracted from plants and microbes and generically engineered. Rennin breaks down the peptide bonds in between the amino acids of milk protein in a process called proteolysis, causing hydrophobic casein proteins to unite around fat and calcium and precipitate as curd. The remainder, whey, just mainly water, is left behind. Eight pounds of milk will produce a solemn 1.25 pounds of curd.

Next, the curds are dehydrated and pressed such that the fats and proteins are concentrated times ten, or more. Salt is added to enable dehydration. Along with salt, mould spores can be added. For example, the Penicillium roqueforti fungi is added via ground bread left to go bad in the French Roquefort caves, to make Roquefort cheese.

Finally, the cheese ripens! In this most luxurious stage, the curds are left to age and enzymes and bacteria continuously convert acid, milk fat and proteins into complex flavor compounds. Proteolysis continues as casein is broken into smaller peptides and highly flavorful and smelly free amino acids. Milk-fat, three fatty acids linked to a glycerol backbone, is broken apart particularly by moulds such as P. roqueforti, producing interesting aromas and sharp flavors.

Brie and Camembert age just for a few weeks. With these soft cheeses, more of the whey is left in with the curds, allowing for a moist and airy texture, enabling moulds to grow. These cheeses unfortunately spoil faster. The surface mould creates an enzyme that breaks down casein protein, turning it runny and soft.

Conversely, sharp cheddar and Parmesan may be aged for many years. The more diverse the enzymes and bacteria, the more complex the flavor of the cheese.

Processed cheese is produced by melting natural cheese with emulsifying salts and is then cooled and molded. Milk powder, casein products, flavors, colors, and preservatives, and stabilizers may all be added.

http://www.idfa.org/news-views/media-kits/cheese/history-of-cheese

http://www.seriouseats.com/2015/02/best-northeast-cheese-cabot.html

http://foodreference.about.com/od/history_myths/a/The-History-Of-Cheese.htm

http://www.swissworld.org/en/switzerland/swiss_specials/swiss_cheese/history_of_cheesemaking/

Episode Three: Yogurt.

Yogurt! It’s simply fermented milk. Yum. Milk, as a review, is a white liquid produced by the mammary glands of mammals. Yum, again. Intended to be a source of nutrition for baby mammals, milk is a colloid of butterfat globules within a water-based fluid that contains casein (milk protein), salts, minerals, vitamins and carbohydrates. A carb of particular importance is lactose, a disaccharide (composed of two monosaccharides fructose and galactose joined together minus one water molecule) that gives milk its sweet flavor.

History:

Yogurt was probably first created by Central Asians in the Neolithic Age (10,200 BC – 3,000 BC). Bacteria that had originated on plants may have been transferred to the udders of cows via grazing or who knows what. Perhaps nomadic herdsmen may have kept milk in carrying containers like animal stomachs, which contained bacteria and turned the milk into yogurt. Since then, yogurt has been widely consumed throughout Asia, India, and Europe, and the Middle East for millennia. Other forms of fermentation, like alcohol-making, dates back to 7000 BC in China, and have also been practiced throughout history all around the world.

Louis Pasteur made the connection of yeast to fermentation in 1856, establishing that fermentation was like respiration (another cellular process) without air (or oxygen, hence, anaerobic).

Science:

The bacteria used to make yogurt are called bacterial cultures. I highlight this to myself because once I tried to explain them to a friend as “bacterial creatures”. Lactobacillus thermophilus and Streptococcus bulgaricus are their precise names. They ferment lactose into lactic acid, which then acts upon casein to give yogurt its texture and tanginess. Because it has much less lactose, yogurt can be consumed by many of the lactose-intolerant persuasion.

Back up though, what is fermentation? It’s a metabolic conversion that cells undergo all the time, to create ATP, which transports energy between cells. First, via the exothermic glycolysis, sugar breaks into pyruvate (an acid) and free energy, which is used to create ATP. Pyruvate converts into lactate, or lactic acid. This reduces the pH of the milk, killing harmful bacteria, making food tangy. Also, the hydrophobic protein begins to denature*, then reassembles with hydrophobic molecules like fat which creates a web-like structure that traps water and creates a semi-solid structure. Other forms of fermentation turn carbohydrates into carbon dioxide and ethanol.

Now that you understand zymology it’s time for some fun facts.

Recipe:

Buy some whole milk and some full-fat “starter” yogurt. This results in a creamier, fattier, tastier yogurt.

In a sterilized pot, heat your milk to about 178 degrees Fahrenheit, or to the point that it’s beginning to form bubbles. This kills bad bacteria. It will also denature some milk proteins and create a finer consistency.

Let the milk cool down to 115 degrees. For each quart of milk, add 2 tablespoons of active yogurt. The bacteria in it are thermophilic and prefer a warm temperature for growth. Put your milk in a warm container, cover it, and keep it warm for about four hours for it to set. My mom would put it in the oven she had used earlier in the day.

Refrigerate the container for several hours.

*What is denaturing again? It’s why boiled eggs become hard and why cooked meat becomes tough. When proteins are formed, they fold into themselves, as the hydrophobic elements curve inward and the hydrophilic elements stay on the outside. When a protein is denatured, these structures are broken and altered. Denaturation is caused by acids, bases, solvents, and heat.

I’m no scientist. Wikipedia helped me a lot with this one. Also, this link:

https://microbewiki.kenyon.edu/index.php/The_Role_of_Bacteria_in_the_Health_Potential_of_Yogurt#The_Biochemistry_Behind_Yogurt