L21 Enhancing Nutrient Bioavailability

What foods have shown the success of fermentation throughout history?

chocolate, coffee, wine, beer, yogurt, cheese, bread

What is the biggest challenge associated with protein?

it is not sustainable to grow foods to feed animals, and then eat the animals (as the animals concentrate the protein from the plants and build themselves from it) for 8 billion people

• protein is the limiting macronutrient amongst everyone

How are people trying to make protein intake more sustainable?

• eat plants and accept that there are less proteins in some sources

• make use of micro live stock

  • increases efficiency

• feeding plants to microorganisms

What are three forms of nutritional improvements?

• protein complementation

• enrichment

• fortification

What are limiting amino acids?

the amino acids that are limiting relative to the amount thats in the food

to your actual essential amino acid requirements

What are three different ways to measure the quality of protein sources?

• Amino Acid Score (AAS)

• Protein Digestibility-Corrected Amino Acid Score (PDCAAS)

• Protein Efficiency Ratio (PER)

What is the Amino Acid Score (AAS)?

• reference protein is an ideal protein that contains all the essential amino acids in sufficient amounts

• does’t take into consideration digestibility

What is the Protein Digestibility-Corrected Amino Acid Score?

• number one utility today in terms of determining quality of different sources

• take into account the digestibility of protein

What is the Protein Efficiency Ratio?

• measurement that has been used historically involving rodent trials

  • compares how much rodents grow in weight as a function of the amount of protein that they were given

  • not adequate in predicting how well humans will perform on these proteins

What four amino acids tend to be limiting and are especially important when considering the growth of children? What kind of foods are typically limited in these sources?

1) lysine

2) s-amino acids (methionine and cysteine)

3) threonine

4) tryptophan

these are primarily limiting in plant-based sources of proteins

Building structure from proteins in the human body is limited by what?

we can only build structure as big as the first limiting material/amino acid

• these amino acids that build this structure comes from protein breakdown

• the closer the initial structure that is being broken down is to the final composition/protein, the easier it is to build

What plant protein sources are low in lysine? Which are high in lysine?

• low →corn and cereals

• high → legumes, soybeans, nuts

Which plants sources are high in s-amino acids (methionine and cysteine)? Which one’s are low?

• low → legumes (beans)

• high → cereals (whole grain)

The concept of limiting amino acids from different food sources for a complete diet is also true for?

• vitamins

• minerals

• essential fatty acids

• all of the above

• none of the above

all of the above

What are the four different types of protein quality derived from mixing protein sources?

1) Type I

2) Type II

3) Type III

4) Type IV

What is type I?

• both amino acids have similar limitations in terms of the essential amino acids

  • has no effect

What is type II?

• supplementation

• quality of protein B is better than protein A (but A is still pretty good, just not as good)

  • add so much B that it plateaus because that’s as good as its going to get (as good as B can be)

What is type III?

• true complementation

• quality of protein A + B is better than their individuals parts

True complementation occurs when?

• a high quality and a low quality protein mix

• two proteins of intermediate quality mix

• enzymes break down proteins

• meats and plant proteins mix

• none of the above

two proteins of intermediate quality mix

What is type IV?

• supplementation

• protein B is so superior to protein A that every time you add B you get increased protein quality

  • primarily drive by how low of quality A is, not really about how good B is

Why do we add additional nutrients to foods?

• nutritional deficiency

• restoration of nutrient loss

• improving the quality of a replacement food

• balance nutrient content of food

• compensate for decreased bioavailability

What is the definition of fortification?

refers generally to nutrient addition in food

What is the definition of enrichment?

addition of thiamin, riboflavin, niacin, and iron to cereal products

• enrichment now includes folic acid

What is the definition of compensation?

new term used to describe nutrient addition to compensate for reductions in bioavailability

What is an example of us adding nutrient to food due to nutrient deficiency?

iodine in salt

What is an example of us adding nutrient to food due to restoration of nutrient loss?

cereal enrichment

• tend to process cereal, therefore we enrich it

What is an example of us adding nutrient in order to improve the quality of a replacement food?

adding vitamin A in margarine

What is an example of us adding nutrient to food in order to balance nutrient content of food?

meal replacers/instant breakfast

What is an example of us adding nutrient to food in order to compensate for decreased bioavailability?

fat-soluble vitamin in olean (fat substitute)

What are rules surrounding nutrient fortification?

• intake of nutrient (in absence of fortification) is below the desirable level in the diet of a significant number of people

• fortified food is consumed in sufficient quantity to contribute significantly to the diet of the population

• addition of the nutrient is unlikely to create an imbalance of essential nutrients

• nutrient is stable under proper conditions of storage and use

• nutrient is physiologically available from food to which it will be added (bioavailable after addition)

• there is reasonable assurance against intake sufficiently in excess to be toxic

  • responsibility of industry to prove this to the government

Is food fortification an easy process?

No

• takes long have to assess many factors

What is the issue with dietary reference intakes?

population is diverse with varying nutritional needs

• overdose people while taking into consideration upper limit

What is NOAEL?

no observed adverse effect level (upper limit)

What is LOAEL?

lowest observed adverse effect level (minimum need for adverse effects)

What are some challenges surrounding fortification?

• changes in sensory attributes of food (color, taste, aroma, texture)

• stability in food

• uniform distribution in food

• risk of approaching upper level of recommended intake

What things do you need to follow/document once you have developed a nutritionally fortified food?

• contribution food makes to nutrient intake amongst populations and that it is solving the nutritional problem

• potential nutrient interactions

• stability of nutrients vs. handling and processing conditions to maintain safety and quality

Describe the changes in nutrient specific disease from the 20th century to now. Why did this change?

• early 20th century, people were dying largely from infectious diseases that were food borne

  • led to the branded product business model that sold food along with the guarantee of safety

• now, people are dying due to non-infectious/contagious metabolic diseases (heart disease, cancer, obesity, diabetes) but these are still driven by diet

  • need to incentivize industry to make foods healthier

What is nutrient labeling?

the ongoing process of monitoring and regulating the industrialization of nutrition in food products