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History… Molecular aka who tells the tale! Gastronomy Most commonly repeated What is molecular gastronomy? While chefs/cooks were Molecular gastronomy was coined in Modernist cooking, science and cooking… 1992 by Hungarian physicist Nicolas Kurti and Herve This (who like to be using science and technology to make food… experimenting with considered the father of Molecular the more unique versions of foods the more “molecular” scientific tools to make Gastronomy) unique foods, a group of scientists and cooks, bakers created a food and science themed meeting… But who really said what? “The scientific study of deliciousness” - Harold McGee

But that name Spherification Elizabeth Cawdry Thomas - London Cordon Bleu alumna - Instructor at cooking school in Berkley Shaping liquids into spheres using gels for a Kurti was part of a core Direct and Reverse unique visual and culinary experience of scientists and culinary Spherification experts that found - Use low pH, calcium funding to bring the mix and sodium alginate of science and cooking to to make thin gel Harold McGee Shirley Corriher Erice Italy. membranes After Thomas attended a scientific conference with her physicist husband in Italy, dinner discussions led to the undervalued idea of science of cooking with other scientists. Encouraged, she organized a workshop which would be directed by Kurti. The initial conference name “science and gastronomy” was thought frivolous and a group of participants voted on the name ”Molecular Gastronomy”. Corriher tells that it was to get the attention for funding. McGee writes Kurti wasn’t part of this first meeting.

Sodium Alginate

Isolated from kelp and brown seaweed. - Glucuronate and Mannuronate polymer - Carboxyl groups of Alginate a whole family of linear copolymers containing blocks of (1,4)-linked β-D- alginate will cross link mannuronate (M) and α-L-guluronate (G) forming a long polymer gel residues. The blocks are composed of consecutive G residues (GGGGGG), Used as a hydrogel to deliver consecutive M residues (MMMMMM), and Drugs in slow release alternating M and G residues (GMGMGM)

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Direct Spherification

Alginate Solution pH! R-COOH remember we use acidic juices! + • Calcium ions are added and create links between Before alginate can thicken or gel a liquid, it needs to Flavoring the individual polymer be evenly dispersed into that liquid (with no lumps) and hydrated (so that each molecule is surrounded chains of the alginate. by water). • As alginate drops hit the • These cross-links cause Problems With Direct calcium solution they This sounds simple, but it sometimes can prove Spherification the polymer chains to immediately gel via entangle and are therefore difficult. cross-linking. restricted in their motion. • Time sensitive Dispersing alginate into hot liquid tends to cause it • Shell is formed at the • Restricted motion to hydrate and gel before the powder has been Calcium Ion interface of the 2 • Liquid interior increases the viscosity of dispersed. The resulting lumps are unpleasant and Bath solutions. continues to gel. the solution and traps cause inconsistent results. For this reason, it’s always • Calcium ions still exist in • Sensitive to acid. water in its networked best to blend alginate into a very cold liquid or to the network’s water. structure. first dry blend it with an ingredient like sugar.

Reverse Spherification

Calcium Ions Advantages of Reverse + Spherification Liquid Flavorings • Spheres can be isolated and interior Reverse does not solidify. Direct • As drops of liquid hit • Not sensitive to pH the alginate, shell is • Calcium limited! formed. • Shell is formed on Alginate outside at interface. Bath • Calcium ions diffuse out of liquid and hit the interface.

Foods as Air

Foams – basic emulsification as an “air” that dissolves in your mouth - Colloidal system (dispersion Culinary foams are often juices or of particles in an aqueous vegetable purees, soups and stock bases medium) where particles are gas bubbles and the medium “thicker foams” include whipping is a thin liquid (gas in liquid creams, meringue, latte, and mousse emulsions) - These emulsions are Emulsifiers include lecithin and proteins (gelatin) stabilized into a cellular - Ampapathic non-polar portion lines up against spongy or rigid for my air with polar end H bonds to water emulsification Ostwald ripening: smaller bubbles merge - Viscosity to slow liquid – air movement as gasses diffuse through liquid. Driven stabilizes. - Solidifying foams with heat (meringue) traps by higher pressure in small bubbles than the air larger bubbles Coalescence: limited by strength of liquid - Gels stabilize to near solid state (marshmallows)

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Gelification

It is the process of turning a liquid into a Examples of gelification agents include: viscous gel with solid, Agar agar, carrageenan, gelatin… jelly-like material. “liquify foods, solidify liquids” for a unique Agar agar – from red algae delivery of flavor”

One form of carrageenan – from seeweed

Meat Glue Simple nucleophilic attack!

Transglutaminase – Similar to other calcium dependent enzyme isolated fro enzyme regulated clotting factors from reactions. blood, bacteria or plants. - Generates a stable isopeptide bond of lysine and glutamine between two proteins (crosslinker)

Meat Glue Examples Deconstruction

This technique involves Transglutaminase, breaking down the elements Yep and hot dogs also called meat Imitation crab of a dish and rebuilding the presentation. Usually, a glue, is an enzyme deconstructed dish consists of multiple components of a that can be used to dish that are presented bind proteins to make together. Shrimp noodles! uniform portions of For example, you can serve a This technique provides a fish filet, tenderloins, small cake next to the frosting basis for developing or topping with bits of a unique presentation and etc. that cook evenly dehydrated marshmallow on plating method for a the side. molecular gastronomy creation. Mock filet mignon

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Not “new” nor “boiling” Sous Vide

French for “under Used in restaurants to prepare food with higher vacuum”. But not shelf life and fast production ’90s really - Circulating - Used in top restaurants since the 70’s water bath with Efficient heat transfer (water vs air as a medium) precision control. and increases shelf-life with elimination of Food is NOT contamination during storage immersed in the water (that is par Prevents oxidation and evaporative losses and boiling) but is in a bag volatile flavorants lost during traditional cooking with air removed. Pasteurization at lower temps for repeatability It is a way to heat the entire food at the “core” temp to denature protein without losing the water holding capacity. Also pasteurizes food. Makes tough cuts traditionally braised or boiled tender with medium-rare doneness.

Temp and Time Fixed time, increasing temp

Denaturing “melting” proteins is one of the three reasons food is cooked. - Softens the meat to the tooth. 61.5 °C/143 °F: conalbumin denatures and causes the egg white to - Connective tissues form a loose gel; and collagen as well 64.5 °C/148 °F: livetin denatures and causes the egg yolk to form a as myosin are all tender gel; Egg cooked at 60 °C/140 °F for 45 min, 90 min, 3 h, denatured but 70 °C/158 °F: ovomucoid denatures and causes the egg white to 6 h, 12 h, and 24 h. The texture of the 3-h-egg's yolk partially in a med-rare form a firm gel (the egg yolk also coagulates around this was noticeably thicker than the 90-min-egg's yolk, steak temperature); 84.5 °C/184 °F: Ovalbumin denatures and causes the egg white to which was thicker than the 45-min-egg's yolk. become rubbery

But is it safe?

Muscle (beef, pork, chicken) is ~75% water, 20% protein Time and & 5% fat (varies on cut…) temp Connective fiber tissues denature at different rates. - kind of During heating, the muscle fibers shrink transversely and longitudinally, the sarcoplasmic proteins aggregate and gel, CV =CV Collagen content and and connective tissues shrink and solubilize. primary sequence of fish vs beef provides a different - muscle fibers begin to shrink at 35–40 °C/95–105 °F up to melting point 80 °C/175 °F. - The aggregation and gelation of sarcoplasmic proteins Each dot is how long it takes at a given time and temp to reduce pathogen begins around 40 °C/105 °F ton 60 °C/140 °F. Results in less connective - Connective tissues start shrinking around 60 °C/140 °F but with aa 7-log10 lethality. Reduction that ensures 1 of 10 million bacteria will tissues and tender meat contract more intensely over 65 °C/150 °F. survive… - The slow changes mainly increase tenderness by dissolving - At lower temps, proteases collagen into gelatin and reducing inter-fiber adhesion. also are active!

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Sooo what else? Finish it!

LN2 hamburgers? Maillard and caramelization

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