lecture 2 Flashcards
compare the difference between animal vs plant lipids
- Animal lipids tend to have more saturated fats and cholesterol, such as butter, lard, and dairy fats.
- Plant lipids are predominantly unsaturated, offering health benefits (e.g., olive oil, sunflower oil).
compare the difference between animal vs microbial lipids?
Animal lipids often contain complex mixtures of fatty acids, while microbial lipids can be tailored to specific needs (e.g., high PUFA content in fungal oils).
Compare the difference between plant vs microbial lipids
Plant lipids rely on agricultural production, while microbial lipids are produced in controlled fermentation environments, potentially offering sustainability advantages.
Asses the nutritional quality of animal lipids
High in saturated fats, which can contribute to cardiovascular diseases if consumed excessively. However, fish and marine sources are rich in omega-3 fatty acids, promoting heart health.
Asses the nutritional quality of plant lipids
: Generally considered healthier due to their higher content of unsaturated fats. For example, olive oil contains high MUFA levels, and nuts provide essential fatty acids.
bacterial sourced lipids are good why?
Emerging as a sustainable and nutritious alternative, particularly for PUFA-rich oils like DHA from microalgae, which mimic fish oil benefits without ecological harm.
In animal sources, what is the cause for compositional differences betweeen sources??
- breed
- sex
- location of fat, and matuarity of fat
- season of the year
- type of diet the animal is consuming
- depending on their digestion, if they are ruminants or non-ruminants meaning are they primarly herbivaors who have a stomach designed for fermentation like cows or non ruminats where they digest via enzymatic digestion like pigs
in plant sources, what is the cause for compositional differences between sourcez?
- species, gentic variation
- part/location like is it from the seed, fruit or felsh
- condition of climate
- soil type
- plant maturity and health
- prcoessing method
in microbial sources what is the cause for the compositional differences between sources?
- substrate
- type of microorganims
- type of process
- species, subspecies
- fermenation and cultivation conditions
What are animal sources of lipids?
- meat (subcutaneous fat of meat)
- milk and dairy products
- egg
- fish
which meat source contains the top 3 highest upper limit of fat content
- horse (12.1 g/100g)
- chicken (11.6)
- beef (9.2)
define the difference between intermuscular fat and intramuscular fat
intermuscular fat is fat that is found between the muscles, forming the “seams”, Its visible seperation between muscle groups. And intramuscular fat is within the muscle fibers forming that marbling look
what is subcutaneous fat and what is its lipid composition like?
It is the layer of fat which is located directyl beneath the skin. It has a high fat content, which is mostly saturated fatty acids and monunsaturated fatty acids and low levels of polyunsaturated fatty acids
what are the main fatty acids in subcutatenous fat?
Myristic acid (C14:0), palmitic acid (C16:0), and oleic acid (C18:1n-9)
what is the lipid composition of whole milk milk look like?5
whole milk must contain at 3.25% milk fat but this number can vary depending on species of animal. The fatty acid profile of milk is predomintely made of saturated fatty acids, then MUFA and finally PUFAs are a minor part
why is cholesterol higher in dairy products compared to milk?1
This is due to the concentration of fat. During processing water is removed, resulting in a greater concentration of fat, and cholesterol is found in the fat portion of milk so logically this means that there will be higher levels as the fat is more concenrated
in terms of cholesterol which milk has the highest cholesterol level?
ewes milk
order dairy products from highest to lowest fat content
- butter
- cream/cream cheese
- cheese
- yogurt
describe the lipid compistion of eggs, and factors that determine lipid compisition
Eggs are a rich source of essential fatty acids like lineoleic acid and high in cholesterol. Eggs contain 8.7-11.2 grams of fat per 100 grams. The lipid composition of eggs depends on diet, breed and age when hen lays the egg
describe the lipid composition of fish and marine sources
Fish are rich in a variety of lipids which make up 0-25% of their composition including phospholipids, sterols and sterol esters, and waxes. The fatty acid composition is vast as well with over 50 different ones, inclduing essential fatty acids and long chain fatty acids.
why are fish rich in fatty acids (specifically PUFAS)
Mainly due to their enviroment and what they eat. Fish that live in cold enviroments need flexible cell membranes to survive at those cold temperatuers. PUFAs like omega-3 stay liquid at low temperatures which allows for that flexible membrane. Fish eat a lot of algae which is rich in omega-3 PUFas .
What are the origins of plant sources of fats and oils?
- seed oils ( rapeseed, sunflower, soybean)
- fruits (avocado, olive)
- nuts (almond, hazelnut, walnut)
which type of oil makes up the most oil production in the world?
palm and palm kernal
why did we need to start using microbial sources for lipids?
There was an increased demand for lipids, and the number of people are growing, and in order to meet needs we need another source. These oils can be used as a sustainble alternative to traditional sources, while mimicing the composition of lipid soucrs like fish oil)
what are the different microbial sources of lipids?
- yeast oils
- fungal oils
- microalgal oils
- bacterial oils
- thraustochytrids oils
what is the composition of microbial sources of lipids like?
high in PUFA especially omeg-3 and 6
describe yeast oils
They are produced by using carbon sources like glucose, arabinose, glycerol and strach
- describe fungal oils
They are fungi, which can make more PUFAs than yeast and can accumalte up to 80% lipids on a dry weight basis (mortierella). They are similar to veggie oils, in their compsosition
what are Microalga oils rich in?
Are rich in DHA and EPA
- describe bacterial oils
These oils are more often used for biodegradable plastic, household goods, comsmetics and medical applications. Some of these bacteria can produce PUFAs like EPA and DHA.
what are thrasyochyrtids oils ?
oils coming from non-photosytntheic marine derived oleaginous microrganisms
what is the waxy substance inside whales head called and what is its function
spermaceti, is essential for signal transmission
which meat contains PUFA
rabbit and horse meat
rate the level of saturated fatty acids in animal sources from highest to lowest
- milk
- sheep
- beef
- chicken
- turkey
- marine fish
