Midterm - Intro and Proximate Analysis Flashcards
essential nutrient
chemical/substance that is required for metabolism, but cannot be synthesized/synthesized rapidly enough
what is the criteria for nutrients to be essential to the human diet
- removing the nutrient causes a deficiency and decline in health
- putting the nutrient back into diet corrects the problem and health will return
when do nutritional deficiencies occur
persons nutrient intake consistently falls below the recommended requirement
deficiency
prevention of disease
nutritional requirement
ensures optimal health
what are daily values based on
2000 calorie a day diet
what are used to make dietary reference intakes
daily values
dietary reference intake (umbrella term)
set of reference values for nutrients
what does DRI reference
- estimated average requirement
- recommended dietary allowance
- adequate intake
- tolerable upper limit
when were DRI’s introduced
1997
what establishes nutrient requirements
- estimated average requirement
- recommended dietary allowance
tolerable upper limit:
the highest level of continuous daily nutrient intake that causes no risk of adverse effects
when is AI proposed
when sufficient evidence is not available to establish an EAR and RDA
what is an AI determined based on
intake in healthy people who are assumed to have an adequate nutritional status
what is the AI expected to do
meet or exceed the needs of most individual
what are the organic nutrient classes
macronutrients and vitamins
what are the inorganic nutrient classes
minerals and water
food analysis
the development, application and study of analytical methods for characterizing foods and their constituents
what are the 2 assumptions made for the Kjeldahl analysis
all nitrogen is in protein
all protein contains 16% nitrogen
3 main steps to the Kjeldahl analysis
- digestion
- distillation
- titration
what does crude fibre tell us about in proximate analysis
cellulose and lignan
what does the term dietary fibre refer to
all fibre (both soluble and insoluble)
3 insoluble fibres
cellulose
lignin
hemicellulose
3 soluble fibres
pectins
gums
mucilages
characteristics of insoluble fibres
remains intact through intestinal tract
- does not dissolve in water
characteristics of soluble fibres
forms gel
- dissolves in water
downfalls of proximate analysis
no info on digestibility
no info on specific amino acids, minerals, lipids or carbs
what does the van soest method differentiate between
insoluble fibres
- cellulose and hemicellulose
- lignin
what does the van soest determine
fermentable and non-fermentable CHO
what does the Southgate method provide
information about sugars starch and various fibres