Transcript Food + Science - Brian D'Amico
Food + Science Natures Medicines Genetically Modified Organisms (GMO) Molecular Gastronomy The Science Behind Cooking
Jude E. Mathews, Ph.D.
Nutraceutical, Phytochemical, Antioxidant
The word foods, Nutraceutical (nutrient) that refers to foods or parts of provide medical or health benefits, including the prevention and/or treatment of disease.
Phytochemical is a term that means plant chemical.
The word comes from the Greek root “phyto” meaning plant.
Phytochemical refers to a chemical substance obtained from plants that is biologically active but not nutritive.
An Antioxidant is a molecule capable of slowing or preventing the oxidation of other molecules.
A Dietary Antioxidant is a substance in foods that significantly decreases the adverse effects of reactive species, such as reactive oxygen and nitrogen species, on normal physiological function in humans.
The Healing Power Of Food (Antioxidants)
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Back in 400 B.C., the Greek physician Hippocrates said, "Let food be your medicine and medicine be your food." Today, good nutrition is more important than ever. At least four of the 10 leading causes of death in the U.S. (heart disease, cancer, stroke and diabetes) are directly related to way we eat.
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Recent research has shown a significant relationship between antioxidants and disease (mainly cancer) prevention.
The Power of Antioxidants
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Antioxidants are substances that may protect cells from the damage caused by unstable molecules known as free radicals.
Free radical damage may lead to cancer.
In humans, the most common form of free radicals is oxygen. When an oxygen molecule (O 2 ) becomes electronically charged or “radicalized” it tries to steal electrons from other molecules, causing damage to the DNA and other molecules. Over time, such damage may become irreversible and lead to disease including cancer.
Antioxidants interact with and stabilize free radical molecules and may prevent some of the damage free radicals otherwise might cause.
Examples of antioxidants include beta-carotene, lycopene, vitamins C, E, and A, and other substances.
Considerable laboratory evidence from chemical, cell culture, and animal studies indicates that antioxidants may slow or possibly prevent the development of cancer.
COmmon Reactive Species
hydroxyl radicals ( .
OH) superoxide anions (O 2 ) singlet oxygen ( 1 O 2 ) hydrogen peroxides (H 2 O 2 ) organic peroxides (R-OOH) nitric oxide peroxynitrite
Lycopene
Lycopene is a carotenoid present in human serum and skin as well as the liver, adrenal glands, lungs, prostate and colon. Lycopene has been found to possess antioxidant and antiproliferative properties in animal remains controversial.
and laboratory studies, although activity in humans Lycopene has shown excellent results in vitro but results in vivo are still being studied.
Lycopene
There is a shortage of supportive evidence for the may be responsible for some of “antioxidant hypothesis” as lycopene’s major in vivo mechanism of action.
It is belived that the metabolic products of lycopene, the lycopenoids, lycopene’s reported bioactivity.
It is hypothesized that lycopenoid compounds are produced by an initial cleavage by carotenoid monooxygenase (CMO) II in a manner similar to how retinoids (retinal, retinol, and retinoic acid) are produced from the initial cleavage of β-carotene by CMO I.
Blueberries
This recent study was designed to investigate the chemopreventive activity of blueberry extract in triple-negative breast cancer. Blueberry extract was found to reduce cell proliferation in HCC38, HCC1937, and MDA-MB-231 cancer cells with no effect on noncancerous MCF-10A breast cells.
Ref: Cancer Research, April 2010
Acai
Acai is a Brazilian palm berry and has been reported as the new superfood?
Food scientists report in a 2008 study that the berry has proven its ability to be absorbed in the human body when consumed as a juice or pulp.
The body can only absorb so much at a time, similiar to vitamin C.
In in vitro studies, scientists have shown that acai extracts can trigger cancer cell death and lower inflamation.
ACAI: The Antioxident Leader
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Fruit Freeze Dried Acai Fruit 1027* Cranberry Blueberry (low bush) Plums (black) Plums Blueberry (cultivated) Blackberry Raspberry Apple, Red Delicious (with peel) Strawberry Total ORAC 92 73 62 62
*ORAC results are expressed in mMole Trolox equivalent (TE) per Liter (ORAC) is a method of measuring antioxidant capacities in biological samples
in vitro
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94 53 48 43 36
Broccoli
Current chemotherapies do not work against cancer stem cells, which is why cancer recurs and spreads. Researchers believe that eliminating the cancer stem cells is key to controlling cancer.
The NIH-funded study tested sulforaphane, a natural compound from broccoli and broccoli sprouts, in both mice and cell cultures. Researchers found sulforaphane targeted and killed the cancer stem cells and prevented new tumors from growing.
This research suggests a potential new treatment that could be combined with other compounds to target breast cancer stem cells.
Clinical Cancer Research, Vol. 16, No. 9; May 1, 2010
Definition of GMO
GMOs - Genetically modified organisms GMO
- an organism that expresses traits that result from the introduction of foreign DNA
Major Players in GMO Field
Monsanto BASF Calgene AstraZeneca Adventis
Example of GMO’s
Golden rice – rice that contains beta-carotene (Vitamin A), which is not found in regular rice.
Bt corn – corn that contains a chemical normally found in a bacterium (Bacillus thuringiensis) that is toxic to insects but not to humans.
Herbicide resistant plants.
Example of GMO
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Flavor Savor Tomato (Calgene) Keeps fresh longer than traditional tomatoes, first sold in US market in 1994.
Taken off market two years later because of poor quality.
FlavrSavr TM
Six Primary Areas of GMO
Insect Resistant
Herbicide Resistant
Viruses Resistance
Delayed Fruit Ripening
Altered Oil Content
Pollen Control
What Are Genetically Modified Foods?
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Involves the insertion of DNA from one organism into another OR modification of an organism’s DNA in order to achieve a desired trait.
Arctic fish DNA & Strawberry = A strawberry resistant to frost
Modifying Genes
Also called recombinant DNA technology, molecular cloning, and genetic engineering.
Restriction enzymes are used to “cut” DNA segments from one genome.
DNA ligases are used to “paste” them into another genome.
Foreign DNA
How are genes transferred?
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A particle gun is used to shoot small bits of metal coated with the gene into the plant. Gold is metal of choice.
Benefits of GM Foods
Easing World Hunger Reduced Herbicides Use of Improved Crop Quality Improved Nutritional Quality Reduce Resources Strain on Pesticides and Nonrenewable
Possible Risks of GM Foods
Insects May Develop Resistance to Pesticide Producing Crops
Herbicide Tolerant Crops may Cross-Pollinate Weeds, Resulting in Super Weeds
Certain Gene Products May be Allergens and Could Cause Harm to Humans
Example of GMO Product on the Market Today
RoundUp Ready Corn Before After
Future of GMO’s Edible Vaccines
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Works like any vaccine A transgenic plant with a pathogen protein gene is developed Potato, banana, and tomato are targets Humans eat the plant The body produces antibodies against pathogen protein Humans are Examples: “immunized” against the pathogen Diarrhea Hepatitis B Measles
Creating a Balance
So are GM foods a good or bad thing?
It depends on each individual case.
Consumers, the government and scientists should be responsible for weighing the benefits against the costs.
Leaders in Molecular Gastronomy
Heston Blumenthal, The Fat Duck, Bray UK
Ferrán Adriá of El Bulli, Roses, Spain Adrià, who has been called “the Salvador Dali of the kitchen,” has won global acclaim as one of the most creative and inventive culinary geniuses in the world.
Chef Grant Achatz of Alinea, Chicago, IL Chef Wylie Dufresne, WD~50 NY, NY
Apple Caviar
Caviar?
Grapefruit Caviar
Caviar - Procedure
Juice mixed with Sodium Alginate
Disolve Calcium Chloride in distilled water
Place small drops of juice solution into CaCl solution, wait one minute then remove and rinse
NaCl vs CaCl
EMULSIONS
Mayonnaise is an emulsion, which is a mixture of two liquids that normally can't be combined.
Mayonnaise is made by combining lemon juice or vinegar with egg yolks. Eggs (containing the emulsifier lecithin) bind the ingredients together and prevent separation.
The two liquids would quickly separate again if an emulsifier were not added. Eggs and gelatin are among the foods that contain emulsifiers.
Mayonnaise without an emulsifier
Lecithin and How it Works
Lecithin's binding power (along with that of other emulsifiers) comes from its molecular structure, one part is hydrophobic, making it soluble in oils or fats, while another part is hydrophilic, soluble in water. In essence, lecithin reduces the surface tension of oil and water molecules, which allows them to mix together more easily.
EMULSIONS
Chemically, emulsions are colloids, heterogeneous mixtures composed of tiny particles suspended in another immiscible (unmixable) material.
Emulsions are used in many different ways:
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by pharmacists, as a vehicle for medication
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in photography, to coat plates, film and paper
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in explosives, paints, coatings, make-up and detergents
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in food, including baked goods and confectionery products
What does adding water to scrambled eggs do?
What is the Role of Salt in Taste?
Salt is used in every cuisine around the world It is widely believed that salt intensifies the desirable flavors in food Taste test using Urea and sucrose sloutions, tasting with and without salt