What preserve food??

In our daily life, most of the food we eat now are preserved. What is the common preservative of the food? Food shelf life is a primary concern for both food manufacturers and marketers. A food product's ability to uphold standards of safety and quality for prolonged periods directly affects sales and customer satisfaction.

The 'freshness' of the food is due to the oxidation of the food. Oxidation occurs when molecules in chemically unsaturated fats and oils react with oxygen to form free radicals. Other byproducts are aldehydes, ketones, acids and alcohols, which result in the harsh flavors, odors, changes in texture and loss of nutritional value associated with rancidity. Antioxidants can block the formation of free radicals in food fats by stabilizing their molecular structure.

Here come the antioxidants
Butylated hydroxyanisole (BHA) and the related compound butylated hydroxytoluene (BHT) are phenolic compounds that are often added to foods to preserve fats.




BHA and BHT are antioxidants. Oxygen reacts preferentially with BHA or BHT rather than oxidizing fats or oils, thereby protecting them from spoilage. In addition to being oxidizable, BHA and BHT are fat-soluble. Both molecules are incompatible with ferric salts. In addition to preserving foods, BHA and BHT are also used to preserve fats and oils in cosmetics and pharmaceuticals.

*Gangloside*

From a advertisement that i watch from the tv, it shows that their product which is a milk powder rich in "Gangloside". From the advertisment, gangloside can connect the nerve of the brain more so the childen is more clever~!!?? SO I am wondering what is gangloside? Now let me talk about gangloside~~~

The name ganglioside was first applied by the German scientist Ernst Klenk in 1942 to lipids newly isolated from ganglion cells of brain. For an easily understand, gangloside is lipid that attach on oligosaccaride chain. Ganglioside is a compound composed of a glycosphingolipid (ceramide and oligosaccharide) with one or more sialic acids linked on the sugar chain.


Gangloside

The function of gangloside
Gangliosides found on the surface of oligosaccharide provide cells with distinguishing surface markers that can serve in cellular recognition and cell-to-cell communication. Structures similar to the ABO blood group antigens on the surface of human cells can be oligosaccharide components of glycosphingolipids in addition to being linked to proteins to form glycoproteins.

As the brain develops, there is an increase in the content of gangliosides and in their degree of sialylation. There are large differences between species and tissues. For example, during embryogenesis and the postnatal period in the human central nervous system, the total amount of gangliosides increases approximately threefold.

In mouse brain, the total amount of gangliosides is almost 8-fold greater in adults than in embryos, with a similar shift in composition from simple to more complex gangliosides governed mainly by changes in the expression level and activity of the glycosyltransferases. The techniques of molecular biology, which enable specific enzymes to be eliminated from experimental animals, are now leading to a better understanding of the function of specific gangliosides.

Analysis of Gangloside
Gangliosides are not the easiest of lipids to analyse, as they are most 'un-lipid-like' in many of their properties. For example, in the conventional Folch method for extraction of lipids from tissues, the gangliosides partition into the aqueous layer rather than with the conventional lipids in the chloroform layer. Nonetheless, methods have been devised for quantitative extraction, and they can then be sub-divided into the various molecular forms by high-performance thin-layer chromatography (or less commonly by high-performance liquid chromatography). Nowadays, mass spectrometry is the probably main method for structural analysis and especially for identifying and sequencing the carbohydrate chains, with invaluable assistance from nuclear magnetic resonance spectroscopy.


One of the type of gangloside -- GM2

Gangloside in milk powder
A method of preparing Ganglioside GM3 which comprises converting Ganglioside GD3 into Ganglioside GM3 in an alkaline condition is disclosed. The conversion of Ganglioside GD3 into Ganglioside GM3 is preferably carried out by thermal treating Ganglioside GD3 in an alkaline condition. The thermal treatment is preferably carried out at a pH ranging from 8 to 11 and at a temperature ranging from 30° C. to 140° C.
The Ganglioside GM3 prepared by the method of the present invention is useful as a reagent used in medical, pharmaceutical and biochemical fields, and is also useful as a material for pharmaceuticals, cosmetics, foods, beverages and animal feeds.
Gangloside which develope in milk poewdee for children can help the brain development of children. Children who drink milk that contain gangloside, their brain development will be better because of the joining of the nerve cell of the brain.