6/30/2011
ACS Webinars™
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6/30/2011
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Food Chemistry Series
The Chemistry of Cheese and Why We Love It
Missed it live? www.acswebinars.org/FoodChemistry
ACS Webinars. On Demand.
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What is the
sTraNGesT
thing YOU’VE grilled?
mouflon sheep ostrich
shark
armadillo
cobra ribs
own arm
stink bugs
kangaroo octopus
bone marrow moose
wild goat
squirrel
raccoon crocodile
eel pigeon
deer leg
beaver chicken hearts 5
Food Chemistry Series
Advances & Innovations in Wine Chemistry
Catch the next one live! www.acswebinars.org/FoodChemistry
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Upcoming ACS Webinars™ www.acswebinars.org/events
Thursday, July 7, 2011
Chemistry & The Economy Mid-Year Review Paul Hodges of International eChem
Thursday, July 14, 2011
Publishing Your Scientific Research: A Chat with the Editors Dr. Cynthia Burrows, Senior Editor with the Journal of Organic Chemistry, and Dr. George Schatz, Editor-in-Chief of the Journal of Physical Chemistry.
Contact ACS Webinars™at
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ACS WEBINARS™ June 30, 2011 Advanced Culinary Chemistry — Sizzles for the Summer
Kent Kirshenbaum, New York University
Sara Risch, Popz Microwave Popcorn
Download slides: http://acswebinars.org/kirshenbaum Contact ACS Webinars™at
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6/30/2011
ACS Webinar – Advanced Culinary Chemistry The Science of the Grill
Kent Kirshenbaum Dept. of Chemistry New York University 9
Our objective
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Our focus
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Chemistry: A source of culinary creativity • • • • • • •
Flavor Texture Color Heat & Fuel Health Weather - Indoor grilling Science education 12
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Flavor and Chemistry
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Flavor and Chemistry • Smoke flavors • Maillard or browning reactions
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Smoke flavors • • • •
Lignin pyrolysis products 100s of compounds generated and identified Low temps: carbonyls Higher temps: phenols, isoeugenol, creosols, guaiacols, syringols • Also: polycyclic aromatic hydrocarbons
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Making liquid smoke
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The Maillard reaction • • • • • •
Also known as “browning reaction” Discovered by Louis-Camille Maillard in 1910s Favored at high temp, low moisture, higher pH Reaction between sugars and protein amines Distinct from caramelization Forms brown colors and a variety of flavor compounds
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Insights on Flavor • • • • •
Try different wood smokes (apple, alder, etc.) Evaluate smoke condensation Control humidity Acidic marinades may deter browning reactions Drippings = flavor
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Texture & Chemistry
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Texture & Chemistry • Protein denaturation – collagen – actin & myosin – fish versus meat
• Time and temperature • Marination
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Insights on Texture • “Low & Slow” to break down collagen • Use indirect heat to avoid actin denaturation • Marination and protein hydrolysis are slow
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Meat color and Chemistry
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Chemistry and Color • Maillard reactions • Meat pigments -- protein
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Color change of meat pigment
David Arnold, Cooking Issues
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The structure of myoglobin
Oxymyoglobin can be purified from meat tissue
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Myoglobin and color
N.J. King, R. Whyte J. Food Science, 2006, 71: R31 26
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Metmyoglobin Ferric Fe3+
Oxymyoglobin Ferrous Fe2+
Microburger Biochemistry S. A. Bylkas & L.A. Anderson J. Chem. Education, 1997, 74: 42627
Myoglobin color
Left: Metmyoglobin
Right: Oxymyoglobin
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Myoglobin denaturation
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Heme Iron ligands and color
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Carboxymyoglobin
1 week old tuna steak, Left: incubated with CO gas
1 week old sirloin
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Nitrosohemochrome & “Smoke Ring”
Nitrogen dioxide (NO2, leading to nitric acid and nitrosohemochrome); promoted by high nitrogen content in fuel; similar to curing with nitrites Littlecreekbarbcue.com
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Winner of the BBQ Survey!
CONGRATULATIONS!
Winner of Harold McGee’s Keys to Good Cooking: A Guide to Making the Best of Foods and Recipes
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Insights on Color • Color is an important but imperfect metric of freshness and doneness • The color of meat and fish can be manipulated
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Heat and Fuel
Modernist Cuisine
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Heat and Fuel • • • • •
Radiant heat drives the cooking process A grill with a shiny interior may help Propane versus charcoal Master the draft Small changes in distance may not greatly modify heat transfer
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Insights on Heat and Fuel • • • •
Control air flow Place Al foil inside your grill Flip often, rest after Use a large bed of coals
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Health & Chemistry
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Health and Chemistry • Chemical – Heterocyclic Amines (HCAs) – Polycyclic Aromatic Hydrocarbons
• Microbial – Temperature – Time
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Insights for Health • Chemical – HCAs arise from both poultry and red meat – Avoid flare-ups, discard char – Marinades and mops – Veggies!
• Microbial – Thermometer – Marinate in red wine, oregano, oregano oil and garlic* *M. Friedman et al., J. Food Science 72, M207-M213, Aug. 2007
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What if I can’t fire up my grill?
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Insights for grill-less cooking • • • • •
Smoked salt Pimenton de la vera Liquid smoke Stove top smoker Smoker oven bags
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Chemistry know-how at the grill • • • • • •
Flavor Texture Color Heat & Fuel Health Indoor “grilling”
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Trust your butcher (or find a butcher you can trust)
Consult your pitmaster!
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Science Education • • • • • • •
Spectroscopy Redox Chemistry Organic Chemistry Thermodynamics pH dependence of reactions Protein structure and protein folding Physiology 47
Chemistry & Cuisine • More delicious food and new recipes • Healthier dietary habits • Enabling science outreach and education
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Resources • Bylkas & Andersson “Microburger Biochemistry: Extraction and Spectral Characterization of Myoglobin from Hamburger“ J. of Chemical Education, 1997, Vol. 74, 426. • King & Whyte “Does It Look Cooked? A Review of Factors that Influence Cooked Meat Color“ J. of Food Science, 2006, Vol. 71, R31. • Modernist Cuisine, Nathan Myhrvold et al. • On Food and Cooking, Harold McGee • Cooking for Geeks, Jeff Potter • experimentalcuisine.com • http://seas.harvard.edu/cooking 49
Acknowledgements • Anne McBride & the Experimental Cuisine Collective • National Science Foundation • Pino and Pino Prime Meats
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Q&A Session Advanced Culinary Chemistry — Sizzles for the Summer
Kent Kirshenbaum, New York University
Sara Risch, Popz Microwave Popcorn
Download slides: http://acswebinars.org/kirshenbaum Contact ACS Webinars™at
[email protected] 51
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6/30/2011
Food Chemistry Series
Advances & Innovations in Wine Chemistry
Catch the next one live! www.acswebinars.org/FoodChemistry
53
Upcoming ACS Webinars™ www.acswebinars.org/events
Thursday, July 7, 2011
Chemistry & The Economy Mid-Year Review Paul Hodges of International eChem
Thursday, July 14, 2011
Publishing Your Scientific Research: A Chat with the Editors Dr. Cynthia Burrows, Senior Editor with the Journal of Organic Chemistry, and Dr. George Schatz, Editor-in-Chief of the Journal of Physical Chemistry.
Contact ACS Webinars™at
[email protected] 54
27
6/30/2011
Help Shape the future of ACS Webinars!
Join the ACS Webinars Audience Advisory Panel! Learn more: www.acswebinars.org
Contact ACS Webinars™at
[email protected] 55
ACS Webinars™
ACS Webinars™ does not endorse any products or services. The views expressed in this presentation are those of the presenter and do not necessarily reflect the views or policies of the American Chemical Society.
Contact ACS Webinars™at
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