fruit and veg Flashcards
what are the morphological characteristics of fruit?
fruits are the mature ovaries of plants with their seeds. generally edible vessel surrounding the seeds. mainly acidic and sugary with several major types of
what are the main types of fruit?
berries, grapes, melons, stone fruit, pomes, citrus fruit, tropical and subtropical
what causes a citrus fruit’s characteristic acidity?
citric acid hyperacidification
what are the common structural features of plant cells?
rigid cell wall, colloidal protoplasm, liquid sap, water (90-96% in veg and 80-90% in fruit)
what is the general composition of fruit and vegetables?
high water content, low protein (<3.5%), low fat (<0.5%), digestible (sugars and starches) and indigestible (cellulose providing fibre) carbohydrates
why is indigestible cellulose important in the diet?
it provides fibre important to digestion
in what forms is water present in vegetable cells?
bound water/dilution water, colloidal bound water, constitution water
what is bound/dilution water?
present in the cell and forms true solutions with mineral or organic substances
what is colloidal bound water?
present in the membrane, cytoplasm and nucleus acting as a swelling agent for colloidal structure substances
what is constitution water?
directly bound on the chemical component molecules and is difficult to remove
how are minerals present in fruits and veg?
present as salts of organic or inorganic acids or as complex organic combinations like chlorophyll or lecithin. they are often dissolved in cellular juice
what is the main dry matter in fruit and veg?
carbohydrates (90%)
what is the main energy component of fruit and veg?
carbohydrates which play a major role in biological systems
what are the main functions of carbohydrates in fruit and veg?
structural components (cellulose), energy reserves (starch), nucleic acid components (ribose), vitamin components (riboflavin)
what is the role of pectins in fruit and veg?
complex, gum like CHOs found in and between cell walls contributing to viscosity and forms gels in solution with sugar and acid.
what is the function of acids in fruit and veg?
gives tartness and slows bacterial spoilage and gives colour to plant pigments that react to pH
what vitamin is associated with orange/yellow or leafy green veg?
vitamin A as these contain its precursor - beta carotene
what vitamin is associated with citrus, tomatoes and cabbage?
Vitamin C
chloroplast
contain chlorophyll a and b
what colours to flavonoids convey?
red/purple by anthocyanins, white/yellow/brown by anthoxanthins
what colours do chlorophylls convey?
green
what colours to carotenoids convey?
orange from carotenes, bright red from lycopenes, yellow from xanthophyll
what do flavanols convey?
food tannins
what health benefits are anthocyanins said to convey?
enhanced heart health, reduced obesity, inhibition of cancer cell growth, however the impact on humans is unknown as this was tested in vitro
