The ideal food for infants is human milk. However, due to certain reasons, some infants do not have access to breast milk. As a greater understanding of the nutritional requirements of infants developed, various alternative infant feeding preparations were manufactured from the late 19th century. However, until the 20th century, there was virtually no safe and reliable alternative to breastfeeding. Most present-day infant formulas in the US market are adaptations of the product designed by H.J. Gerstenberger and co-workers in 1915.
Goat milk modification for infant feeding is still a very new area and has not been achieved in most parts of the world due to the relative differences between goat's milk and cow's milk, as well as differences between these to human milk.
Literature has shown that goat milk adapted for infant feeding might be a suitable substitution for cow milk formulas due to the higher tolerance of goat milk by infants who are allergic to cow milk proteins. The higher protein and non-protein nitrogen and phosphate in goat milk produce a greater buffering capacity than cow milk. Furthermore, many infants allergenic reactions to cow milk, stem from the excess mucus production of this milk, unlike in goat milk.
Some physico-chemical properties of goat milk such as smaller fat globules, higher percentage of short and medium chain fatty acids, and softer curd formation of its proteins are advantageous for higher digestibility and healthy lipid metabolism.
You are invited to post your comments on this topic.
Friday, February 15, 2008
Thursday, February 7, 2008
Food Process Mechanisms Leading to Loss in Protein Quality
During the course of food product development, many formulators often experience loss in protein quality and bioavailability due to processing techniques and other parameters. Below are some of the mechanisms that lead to protein quality loss during food formulation. You are invited to post your comments!
Heat Destruction:
This is the destruction of amino acids contained in proteins by use of very high temperatures, leading to loss in functionality of the protein.
Non-Enzymatic Losses:
This is a loss in protein quality not requiring the action of enzymes. E.g. Maillard browning (formation of brown coloration in foods as a results of amine group of amino acids reacting with the aldose, ketose group of chemical compounds and/or reducing sugars, to give rise to complex products, which results in protein loss).
Protein-Protein Crosslinkage:
This is the formation of new linkages, or the modification of existing linkages between the amino acids of proteins, thereby causing a loss in bioavailability of these amino acids.
Protein Isomerization:
This is the formation of a protein isomer as a result of the processing conditions under which the food was subjected - leading to loss in bioavailability of amino acids in the protein. E.g. conversion of an L-Amino acid to the D-isomer.
Protein Oxidation:
This is the destruction of proteins by autolysis of fatty acids and fat compounds that are either in interaction with the protein or in close proximity to the protein, thereby leading to oxidation of the amino acid contained in the protein.
Alkali Treatment of Proteins:
The use of alkali in food treatment may lead to a loss in protein function, quality and bioavailability. E.g. Formation of hard curd from milk by alkali treatment which results in protein non-digestibility.
Losses by non-reducing mechanisms:
E.g. Caramelization (this is the formation of brown pigments on food surfaces when the amino group of certain amino acids reacts with carbonyl compounds under the influence of high temperatures, leading to losses in protein function and quality.
Heat Destruction:
This is the destruction of amino acids contained in proteins by use of very high temperatures, leading to loss in functionality of the protein.
Non-Enzymatic Losses:
This is a loss in protein quality not requiring the action of enzymes. E.g. Maillard browning (formation of brown coloration in foods as a results of amine group of amino acids reacting with the aldose, ketose group of chemical compounds and/or reducing sugars, to give rise to complex products, which results in protein loss).
Protein-Protein Crosslinkage:
This is the formation of new linkages, or the modification of existing linkages between the amino acids of proteins, thereby causing a loss in bioavailability of these amino acids.
Protein Isomerization:
This is the formation of a protein isomer as a result of the processing conditions under which the food was subjected - leading to loss in bioavailability of amino acids in the protein. E.g. conversion of an L-Amino acid to the D-isomer.
Protein Oxidation:
This is the destruction of proteins by autolysis of fatty acids and fat compounds that are either in interaction with the protein or in close proximity to the protein, thereby leading to oxidation of the amino acid contained in the protein.
Alkali Treatment of Proteins:
The use of alkali in food treatment may lead to a loss in protein function, quality and bioavailability. E.g. Formation of hard curd from milk by alkali treatment which results in protein non-digestibility.
Losses by non-reducing mechanisms:
E.g. Caramelization (this is the formation of brown pigments on food surfaces when the amino group of certain amino acids reacts with carbonyl compounds under the influence of high temperatures, leading to losses in protein function and quality.
Subscribe to:
Posts (Atom)
