What is the gold standard for infant feedings?
- Human milk is the preferred source of enteral nutrition for infants including premature infants and sick newborns.
- The unique composition of human milk is “the gold standard” - the model for infant formulas.
What is the composition of Infant Formulas?
- Protein – 8 – 12% of calories
- Fat - 43 – 49% of calories
- Carbohydrate – 41 – 43%
What is the carbohydrate sources of lactose, sucrose, intermediate sugars (glucose, maltase, glucose oligomers) and starches?
- Lactose – Milk
- Sucrose – Cane, beets
- intermediate sugars (glucose, maltase, glucose oligomers)- Hydrolyis of corn or rice starch
- starches- corn, tapioca
What type of carbohydrates are in term formulas?
What type of formulas are in premie formulas?
What is in lactose?
Lactose = galactose + glucose
When do the major carbohydrate enzymes develop?
- Salivary amylase – 10 weeks
- Pancreatic amylase – 22 weeks
- Lactase – 24 weeks
- Glucoamylase – 24-28 weeks
What is the osmolality of breastmilk?
What is the side effect of formulas with a high osmolality?
Diarrhea, carbohydrate malabsorption
What is the AAP recommendations for infant feedings osmolaity?
American Academy of Pediatrics recommendation is not to exceed 450 mOsm/kg water
What is the osmolality of commercial formulas?
Commercially available infant formulas generally fall between 200 and 400 mOsm/kg water
What is the osmolaity of high caloric formulas?
Osmolality of high calorie formulas may exceed 450 mOsm/kg water
What is casein?
- An insoluble protein in suspension
- Coagulated by acid or remnet and forms a firm curd
- Primary component of cheese
- In high concentration can result can result in lactobezoar formation – like a hairball
What is whey?
- Soluble, globular protein
- Forms small, soft curd
- Contains more cysteine than casein
Compare the whey:casein ratio of breastmilk, cowsmilk and formula
- Bst: 60:40
- Cowsmilk: 82:18
- Formula: 60:40
What are the characteristics of soy proteins?
- A good quality plant protein with small amounts of sulfur containing amino acids and this is compensated for by using higher intake of this protein and/or supplementing with methionine
- Accompanied by phytic acid which reduces mineral absorption and this is compensated for by supplementing with increased minerals
- Also accompanied by anti-trypsin which reduces digestibility which is corrected by inactivating anti-trypsin
What infant has to be fed soy formulas?
Galactosemia but they often times die before they are diagnosed
How is antigenicity modified?
- Antigenicity is the ability of a certain substance to bind to certain products of adaptive immunity
- heat- disrupts the tertiary structure which generally decreases antigenicity
- hydrolysis – disrupts all structure and potentially eliminates antigenicity
What is protein hydrolysis?
Decreases allergenicity and improves the rate of digestion
What is partial protein hydrolysis?
Modest decrease in antigen load but some antigens that are dangerous to a sensitized person remains
What is the result of protein Hydrolysate
- Casein has molecular weight of 70,000 daltons and whey can reach 150,000.
- Casein is incubated with enzyme until very few peptide bonds remain
- Average peptide molecular weight is about 200 with less than 1% having molecular weight > 500 and none detectable above 1200 daltons
Why is casein used as a protein soarce in formulas
- It is thought to be the least allergic source of cows milk and can be broken down easier
- Whey is thought to be the cause of allergy in cows milk that’s why it isn’t used in hypoallergenic formulas
What is extensive protein hydrolysis
- Virtually no antigens remain
- There is a balanced distribution of essential and nonessential amino acids
What is crystalline amino acids
- A result of protein hydrolysis
- Antigen free
- Customized miz that can selectively eliminate an amino acid
What is the Fatty acid profile of human milk
- No one vegetable fat source simulates the fatty acid pattern of human milk
- By combining vegetable fats, resultant blends can approximate the pattern found in human milk
What are the undesirable effects of protein hydrolysis
- Increases free amino acids – causes an unpleasant taste
- Increases osmolality – large protein becomes many peptides and amino acids; replaces disaccharides with glucose oligomers to compensate
- Reduces fat emulsifying properties in formulas – starch is used as a substitute
- Increased cost
What are Medium-chain Triglycerides
- Rapidly and easily hydrolyzed in the absence of pancreatic lipase and/or bile salts or when intestinal surface area is reduced
- 10 carbon atom chain length or less are known to be transported in unesterified form directly from the intestinal tract into the PORTAL circulation rather than via the LYMPHATIC system
What are DHA and ARA and which formulas have it
- Present in breast milk
- Linoleic acid is the precursor of arachidonic acid (ARA)
- Linolenic acid is the precursor of docosahexaenoic (DHA)
- Mead Johnson = LIPIL
- Ross = Advance
- May be important for early brain development and visual acuity
What are Long-chain Triglycerides
- Require bile salts and pancreatic lipase for digestion
- Provide essential fatty acids
What is the partition of daily caloric expenditure in a typical growing premature infant?
How do you increase calories in feedings?
- Verify accurate feeding order and intake
- Use HM with HMF or 24 kcal/oz formula
- Maximize volume tolerated for best nutrient mix before using additives
What additives can be added to feeds to increase calories?
- Microlipid -long chain fatty acids, 4.5 kcal/mL
- MCT oil - medium chain triglycerides, 7.7 kcal/mL; should not be used in continuous feeds
- Polycose - Glucose polymers, 4 kcal per 1/2 tsp
- Rice Cereal - thickener for reflux or aspiration; amount used and effectiveness varies
- Powdered formula - 1/2 tsp per 50mL expressed HM= ~24 kcal/oz
- Similac Special Care 30 kcal/oz
- Beneprotein – 2.8 kcals per ½ tsp; source is whey protein
What is Similac Advance Early Shield
– addition of oligosaccharides (prebiotic) which promotes growth of bifido “good” bacteria
What is Nutramigen AA Lipil –
hypoallergenic amino acid based formula but with long-chain fats
What is Nestle Good Start Premature
- Preterm Infant formula with hydrolyzed whey protein –
- 40% MCT
- 50% Lactose
- 50% corn syrup solids