Lecture 4 Flashcards
What is a veggie?
Plants or part of plants used for food
-raw and cooked
What have the consumption patterns of veggies been amongst Canadians?
Overal consume less then recommend
- females consume more on average than males
- hurting veggie sales and leading to an increase in health related costs
How much has candies field veggie production decrease?
by 2.7% from 2016-2017
-influences such as urbanization, the environment and weather
Which province produces the most veggies?
Ontario with 44% of field veggies and then Quebec
-Ontario also largest producer of greenhouse veggies
Who do we export our veggies to?
US
-exports grew 5.8% in 2017
How much veggies to we import and from who?
- 7 billion worth
- 2 billion from US
- tomatoes, lettuce, peppers, cabbage
How many farms are there now than before and how has that changed veggie production?
1526 farms in 2006 to 1856 farms in 2016 but the production of veggies has decreased
- most veggies going to meat production
- smaller area of land
What are the top 5 blains of new products launched in Canada under the sub-category vegetables?
Kosher Microwaves Ease of Use Organic Ethical-Environmentally friendly package
Why do Canadians feel that the new food guide is too expensive?
Movement of a more plant based diet has lead to a nhigher demand for fruit and veggies and this has lead to an increase in the price of V&F
What are the health benefits associated with eating more veggies?
Reduce risk of:
- certain cancers
- type 2 diabetes
- CVD
whole foods are best
What makes up veggies?
Fibre K Vitamin ACEK, folate, thiamin, niacin, b6 Cu, Mg, Fe, Mn, Choline Phytochemical (carotenoids, anthocyanin)
Why is vitamin c important?
Important for the growth and repair of bones, teeth nd skin
what are the 8 different classifications of vegetables?
- Leaves
- Veggie-Fruits
- Flowers
- Stems/Shoots
- Roots
- Bulbs
- Tubers
- Seeds
What properties do leafy greens have?
More vit a
Ca (but bound to oxalate, effecting absorption)
-storage in high humidity to avoid wilting
What is the name of the compound that is responsible for the green?
Solanine-alkaloid substance and toxic if consumed in large amounts
What are some things we have to look at when purchasing veggies ?
Consider: Cost per serving Seasonality Fresh Frozen Canned
What are convenience veggies?
Veggies that are: Partially processed Value added Fresh cut Packaging: modified atmosphere, hermetic
What is hermetic packaging?
Air tight, no air allowed in package to preserve veggies
How long do veggies have if they are in a modified atmosphere?
21 day shelf life
Why are bean sprouts of concern?
Safety concerns because they grow in warm moist environment they are more susceptible to E. coli and salmonella
-sprouts from soybeans and mungbean seeds
How do bean sprouts get coli and salmonella?
They can come into contact with the bacteria:
- in the farm environment
- during packaging
- transportation
- storage
- prepping
- cooking
When storing veggies what should you be mindful of?
Short shelf life
Respiration and senescing
-cells still consume O2 and give off CO2 after harvest
How should you store veggies?
High humidity
-to about loss of moisture an loss of turgor
Avoid storing by other veggies that are:
- strongly flavoured
- produced by ethylene gas
What is turgor?
The pressure that the full vacuoles (composed of water and solutes), expert on cell walls
-results in a rigid, crisp texture
What is turgor control by?
Osmosis, so once the cells come into contact with the water the wilting will stop
Why aren’t potatoes stored in the fridge?
The cold temperature converts sea h to sugar so you’ll have a sweeter potato
What temperature is best to store veggies?
Varries with the veggie
-ex: tomatoes have the best flavour when stored at room temp
Many other veggies are best stored under refrigeration
-useful for conserving vitamin content
What are the 2 other methods for extension veggie storage?
Coatings: decrease respiration
- veggie oil emulsions
- edible wax: restores natural coating when removed to help extend shelf life
- slows dehydration and decay
Storage
- Controlled atmosphere
- O2 levels reduced to extend storage
Why do we cook veggies?
Improves palatability (flavour can vary though if cooked)
More digestible
Gelatinization of starch
Destroys microorganisms
*volume impacted when cooking
What are the chlorophyll compound derivatives?
Chlorophyll
Pheophytin
Pyropheophytin
Chlorophyllin
What colour does pheophytin produce and how?
Dull olive green
- overcooking
- extended hot holding
- acid
What colour does pyropheophytin produce and how?
dull olive green or olive brown
-common in canned veggies (due to heat treatment during canning process)
What colour doesn’t chlorophyll produce and how?
Bright green
- alkaline exposure
- alkaline can induce nutrient losses (thiamin and vitamin C)
- can impact texture and make it more soft by mostly affecting cellulose and hemicellulose
What happends to chlorophyll when cooked?
Alkaline such as baking soda will brighten the colour
Excess heat and acid will turn the colour olive green
What happens to carotenoids when cooking?
When exposed to air they lose their yellow colour (susceptible to oxidation)
Alkaline= little effect on colour
Over cooking in the presence of an acid will result in isomerization making the colour change from orange to yellow
-carotenoids present in chloroplasts in green leaves
What happens to betalainss when cooking?
Very soluble in water and they leach into the water form tissue when sliced or pared before cooking
What happens to anthocyanin when cooking?
Alkaline turns blue to purple
Acid turns more red
It reacts with tin and iron from cookware which results in a more blue colour
What happens to anthoxanthins when cooked?
May become dark with iron and bright yellow with aluminum
Stable to heat but If prolonged may darken
Alkaline=white/colourless turns to yellow
What can the flavour of veggies be attributed too?
Aldehydes Alcohols Ketones Organic Acids Esters Sulphur containing compounds -mostly in cruciferous veggies
How is the flavour of veggies impacted?
How much water used (loss of vitamins)
Type of cooking method
Over cooked (undesirable flavour)
How do cruciferous veggies have a mild flavour?
- Cooked until just tender
- Cooked in an uncovered pan (allows acids to escape)
- Enough water to almost cover it ( so you aren’t excreting the water soluble vitamins)
When do cruciferous veggies have a strong flavour?
When improperly cooked due to decomposition of certain sulfur compounds
- Hydrogen sulfide and other volatile compounds may produce a strong pungent sulphurous flavour and odour
- Sinigrin>heat> H2S: when you heat the veggie with sinigrin it produces hydrogen sulphide. cooking with the lid off lets the compounds escape
When is the flavour of an onion the strongest?
Raw, we lose some of the strong flavours when cooked in water
-can be sweeter when cooked in small amount of water with lid on
What derivative do onions have?
AA cysteine which has a sulphur group
-acted on by enzymes when cute or peeled to produce volatile sulfur compounds (irritates eyes)
What are the 4 main flavours that veggies produce?
Mild
Strong
Sweet
Bitter
What texture should you cook veggies to?
Tender crisp
What are the fibre components of veggies?
Cellulose/hemicellulos -cell structure Pectins -Glue to keep cells together in plants Beta Glucans -fibre component found in oats Lignin (non carb) -woody/stringy structure Gums and Mucilage -Act as emulsifier and stabilizer -thick gooey substances used in plants
When cooking how does fibre hold up?
Fibre is not lost
Cellulose is softened
Hemicellulose disintegrates in alkaline water
Acid prevents softening
Ca salts make veggie tissues firmer
Pectin substances hydrolyzed, and total pectin appears to be well retained
What are Calcium salts?
They form insoluble calcium salts with pectin substances within plant tissues.
-Commercially traces of Ca are added to canning to preserve the shape
How do you prevent nutrient losses?
Higher nutrient levels when vegetables prepared and used close to time or harvest
Lost during storage (B and C)
-vitamins bay be destroyed by oxidation
Cooking
How are nutrients lost in cooking?
Dissolved action of water- boiling can lead to loss of nutrients in water Chemical decamp (acid/basic) Oxidation of vitamins - mechanical loss of nutrient is a result of pairing Loss of solids into cooking water Volatilization (main component is water that is the main volatile component)
Is Vitamin A water soluble and what is it sensitive too?
Not water soluble
sensitive to O2 and Light
Is Thiamin water soluble and what is it sensitive to?
Is water soluble
Sensitive to Heat (the most)
Is niacin water soluble and what is it sensitive to?
Is water soluble
Not sensitive to anything
Is Vitamin C water soluble and what is it sensitive to?
Is water soluble
Sensitive to O2, light and heat
Is Vitamin D water soluble and what is it sensitive to?
Not water soluble
Not sensitive to anythiing
