50 Fun Facts About Food Science

The browning reaction between amino acids and sugars that flavours seared steak is named after which chemist?

Louis Camille Maillard, a French physician and chemist, first described the reaction, which races along at roughly 140 to 165 °C; that is why dry heat browns food while boiling water cannot.

When sucrose caramelizes, it breaks down into which two simple sugars?

Heat first splits sucrose into Glucose and fructose, which then dehydrate and polymerize into the brown caramel compounds; unlike the Maillard reaction, no amino acids are needed.

Which Japanese chemist identified umami as a distinct taste in 1908 after noticing the flavour of kombu?

Kikunae Ikeda isolated glutamate from kombu broth at Tokyo Imperial University and patented a way to make monosodium glutamate, launching the seasoning sold as Ajinomoto.

Umami receptors respond mainly to glutamates and which other class of compounds found in meat broths?

Nucleotides such as inosinate from meat and guanylate from mushrooms amplify glutamate's umami taste, which is why dashi pairs glutamate-rich kombu with bonito flakes.

Which two wheat proteins form the elastic network we call gluten?

Gliadin and glutenin are wheat's storage proteins; once flour is wetted and kneaded they bond into gluten, which makes up roughly 75 to 85 percent of bread wheat's protein.

Which everyday sauce is an emulsion of oil, egg yolk and an acid?

Mayonnaise stays stable because lecithin in the egg yolk coats the oil droplets and keeps them apart; a popular origin story traces it to Mahón in Menorca in 1756.

The word 'emulsion' comes from a Latin verb meaning what?

The Latin verb emulgere means 'To milk out'; the word was first applied to milky liquids such as almond milk, and milk itself is fat droplets dispersed in water.

Louis Pasteur's 1860s research that gave pasteurization its name was originally aimed at preserving what?

Wine was Pasteur's target: in the 1860s he showed that briefly heating it to about 50 to 60 °C stopped it souring, and the process kills most bacteria while leaving spores intact.

Georges Pralus devised sous vide in 1974 to improve which dish?

Foie gras lost far less fat and kept a better texture when Pralus sealed it in plastic and cooked it slowly in a water bath at Restaurant Troisgros; sous vide is French for 'under vacuum'.

Who coined the term 'molecular and physical gastronomy' in 1988?

Nicholas Kurti and Hervé This launched the term in 1988; Kurti's 1969 Royal Institution lecture The Physicist in the Kitchen famously injected brandy into mince pies with a syringe.

Spherification uses sodium alginate together with which salt?

Calcium chloride supplies the calcium ions that cross-link alginate chains into a thin gel membrane around each drop, so a liquid centre stays sealed inside the sphere.

Which restaurant, run by Ferran and Albert Adrià, brought spherification to modernist cuisine?

elBulli sat in Cala Montjoi near Roses on the Costa Brava; Ferran Adrià joined it as a line cook in 1984, aged 22, and the restaurant served its last meal in 2011.

Why can birds eat chilli peppers without feeling the burn?

Their TRPV1 receptor ignores capsaicin because the bird form of the heat-sensing channel lacks the mammalian binding site; that suits the plant, since birds spread seeds intact while mammal molars grind them.

In which part of a chilli pepper is capsaicin most concentrated?

The placental tissue, the pale pith that holds the seeds, carries the capsaicin-secreting glands; the seeds pick up heat only because they sit against it.

Wilbur Scoville, whose scale measures chilli heat, worked in what profession?

Pharmacist Wilbur Scoville devised his dilution test while working for the drug firm Parke-Davis, thinning pepper extract in sugar water until a tasting panel could no longer detect heat.

How many trained tasters sat on the panel in Scoville's original organoleptic test?

Five tasters formed the panel: Scoville diluted an alcohol extract of the pepper in sugar water until the panel could no longer sense heat, and that dilution ratio became the pepper's rating.

Pectin, the gelling agent that sets jam, takes its name from a Greek word meaning what?

Congealed is the sense of Greek pektikos, the root of pectin; apples, quince and citrus peel are rich in it, while strawberries and cherries have little and need added pectin to set.

Which Harvard professor patented the phosphate baking powder later sold as Rumford?

Eben Norton Horsford, Harvard's Rumford Professor, patented a calcium acid phosphate leavening in 1856 and co-founded the Rumford Chemical Works to sell it; Alfred Bird had sold a cream-of-tartar powder in England from 1843.

Nicolas Appert, the 'father of food science', preserved food by sealing it in what and boiling it?

Glass jars and bottles, corked and wired shut, were Appert's vessels; the French government paid him 12,000 francs in 1810 on condition that he publish his method.

Which civilisation was freeze-drying potatoes into chuño as early as the 13th century?

The Inca left potatoes out on freezing Andean nights and trampled the water out by day to make chuño; the modern process took off in the Second World War to preserve blood plasma and penicillin.

Nixtamalization, soaking maize in limewater, helps prevent which deficiency disease?

Pellagra is niacin deficiency; the lime soak frees the niacin locked in maize so the body can absorb it, and it also loosens the hulls and softens the kernels for masa.

Storing bread where makes it go stale fastest?

In the refrigerator, starch recrystallises fastest at temperatures just above freezing, so chilled bread stales within about a day; freezing halts the process and room temperature slows it.

When you boil an egg, what happens to its proteins to make the white turn firm and opaque?

They denature: heat unfolds the egg's albumin proteins, which then tangle into a solid opaque network; acid and salt can also unfold proteins, which is how ceviche 'cooks' fish without heat.

Egg white is roughly what percentage water?

90 percent of egg white is water, with nearly all the rest protein such as ovalbumin; even so, the white holds about 56 percent of the egg's total protein.

The term 'supertaster' was coined by which experimental psychologist?

Linda Bartoshuk coined the term at Yale in the 1990s for people who find the bitter compound PROP intensely strong, a trait she linked to a higher density of fungiform papillae.

Miraculin, from the West African miracle fruit, makes sour foods taste how?

Sweet is how lemon juice tastes once miraculin binds to the tongue's sweet receptors and switches them on in acid; the protein itself is not sweet, and the effect lasts an hour or two.

At roughly what temperature does a popcorn kernel's hull finally rupture?

180 °C is where the steam pressure inside finally bursts the hull; the kernel then expands to 20 to 50 times its volume as the superheated starch puffs into foam.

A popcorn kernel needs about what moisture content inside its hull to pop?

A kernel at 14 to 20 percent moisture holds enough water to flash into steam and build roughly 135 psi inside before the hull gives way; drier kernels stay unpopped.

Besides its high sugar concentration, which property helps honey resist spoiling?

Its acidic pH, around 3.9, comes from gluconic acid that bee enzymes make from glucose, alongside hydrogen peroxide; few microbes grow in something that acidic with so little free water.

Which gas, also a plant hormone, is used commercially to ripen fruit?

Scrubbing it out of storage air delays ripening, which is how apples last all year.

Cutting an onion releases enzymes called alliinases that lead to which tear-inducing compound?

Syn-propanethial S-oxide forms when a second enzyme, lachrymatory-factor synthase, rearranges the sulfenic acid that alliinase releases; the volatile gas drifts up from the board and stings the eyes into tears.

Roughly what proportion of adults worldwide have lactose malabsorption?

65 percent of adults worldwide are estimated to have reduced lactase activity after infancy; as few as 5 percent of northern Europeans are affected, versus roughly nine in ten in parts of East Asia.

Chymosin, the key enzyme in rennet, curdles milk by acting on which protein?

Casein is the target: chymosin clips kappa-casein, the protein that keeps milk's casein micelles dispersed, so they clump into curd; much commercial chymosin comes from genetically engineered microbes rather than calf stomachs.

Sourdough starter is a partnership between wild yeast and which kind of bacteria?

Lactobacillus species produce the lactic and acetic acids that give sourdough its tang; San Francisco's signature strain was first described in 1971 and named Lactobacillus sanfranciscensis after the city.

Which yeast species converts sugars into carbon dioxide and alcohol in bread and beer?

Saccharomyces cerevisiae, the brewer's and baker's yeast, ferments sugars into carbon dioxide and ethanol; its name is often used as a synonym for yeast, though yeasts span two fungal phyla.

Adding salt to ice around an ice-cream churn works because it does what?

Lowers the melting point of the ice: salt dissolves into the meltwater and the brine can fall to about minus 20 °C, cold enough to pull heat out of the cream mix through the churn wall.

Which 19th-century process makes chocolate smoother by prolonged mixing and grinding?

Conching was introduced by Rodolphe Lindt in Bern in 1879; hours of grinding in a shell-shaped trough shrink the sugar and cocoa particles and drive off harsh volatile acids.

Coenraad van Houten's 1828 hydraulic press squeezed what out of chocolate liquor?

Cocoa butter, the fat that makes up roughly half of chocolate liquor, was pressed out, leaving a cake ground into cocoa powder; white chocolate is made from that butter with milk and sugar but no cocoa powder.

Table salt is often fortified with which element to prevent goitre?

Iodine is needed to make thyroid hormones; without it the thyroid swells into a goitre, and iodised salt, introduced in Switzerland and the United States in the 1920s, nearly eliminated the problem there.

Heston Blumenthal's Fat Duck became famous for which unusual dish?

Bacon-and-egg ice cream became the signature dish at Blumenthal's restaurant in Bray, Berkshire, which topped the World's 50 Best Restaurants list in 2005.

Harold McGee's landmark 1984 book on kitchen science is titled what?

On Food and Cooking first appeared in 1984 and was heavily expanded for a 2004 edition; McGee later wrote a New York Times column, The Curious Cook, debunking kitchen folklore.

Modernist Cuisine author Nathan Myhrvold was formerly CTO of which company?

He spent 13 years at Microsoft and became its first CTO in 1996.

In what year was the browning reaction between amino acids and sugars first described?

1912 is when Maillard reported the reaction to the French Academy of Sciences while trying to reproduce biological protein synthesis; USDA chemist John E. Hodge worked out its mechanism in 1953.

Which probable carcinogen can form as a by-product of the Maillard reaction at high temperatures?

Acrylamide forms when the amino acid asparagine reacts with reducing sugars above about 120 °C, which is why fries and crisps carry most of it; lower temperatures or added asparaginase discourage it.

Applying lye to pretzels darkens them faster because the Maillard reaction speeds up in what environment?

Alkaline conditions deprotonate amino groups, making them more nucleophilic, so the sugars and amino acids react faster; that is why lye-dipped pretzels brown to a deep mahogany.

Which volatile compound with an intense butter-like taste is released during caramelization?

Diacetyl, the same compound that flavours butter and butterscotch, is released in the first stage of caramelization; the brown colour comes from polymers called caramelans, caramelens and caramelins.

At roughly what pH is the rate of caramelization slowest?

Around 7, neutral pH, is where the reaction crawls; both strongly acidic and strongly basic conditions accelerate it, as do impurities such as the molasses in brown sugar.

Butter is unusual among food emulsions because it is which type?

Water-in-oil describes butter: tiny water droplets sit inside a continuous fat phase, the reverse of hollandaise, cream and homogenised milk, which are all oil-in-water.

The spontaneous emulsion that clouds pastis or absinthe when water is added is called what?

The ouzo effect is a spontaneous nanoemulsion: anethole and other anise oils dissolved in the spirit form droplets of a few hundred nanometres when water dilutes the alcohol, scattering light into a milky cloud.

In which US city is the Institute of Food Technologists headquartered?

Chicago houses the Institute of Food Technologists, founded in 1939; its definition of food science runs from the causes of food deterioration to the principles of processing.