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Tuesday, September 6, 2011

Ethanol production from algae

The major raw materials for ethanol production are carbohydrates such as starch and glycogen. Naturally these carbohydrates present in significantly large quantities in some algae species. Species of algae such as chlorella, chlamydomonas, spirulina, dunaliella, scenedesmus etc. contain up to 60% of their dry weight starch and glycogen (polysaccharides).

 Ethanol is produced from algae by the process of fermentation. The process of fermentation is both easy and cheap. It is carried on by the help of a fungus called yeast, the same yeast that is used for the production of alcoholic drinks. All algae contain three components these are the carbohydrates, the proteins and the lipids. The carbohydrates or polysaccharides can be used for the production of ethanol, the proteins can be used by the food industries and the lipids are used as a raw material for the production of biodiesel. Both ethanol and biodiesel from algae can be used effectively to run any engine such as cars. They both are environmentally friendly and have great impact to reduce the global carbon emission and global warming.

Genetic engineering is playing a major role in developing new strains of microalgae that have the ability to produce ethanol by using the carbohydrates they produced. One good example of such microalgae is a Cyanobacteria called Synechocystis.

Most algae produce ethanol naturally in response to anaerobic conditions or under no oxygen conditions. In anaerobic conditions algae force their cells to enter to an energy phase to produce one ATP molecule for survival. And as a byproduct produces ethanol. Now days genetic engineers are working to increase ethanol production by manipulating the natural response of algae for anaerobic situations.  The species of algae such as spirulina, microcystis, chlorella, chlamydomonas and oscillatoria are under the spotlight to improve the production of ethanol by manipulating and enhancing their natural response to anaerobic conditions via genetic engineering. 

Monday, September 5, 2011

Macroalgae uses to produce food products


Macroalgae or seaweeds are very common staple foods in most of the Asian countries such as Korea, China, Indonesia, Japan, India, Philippines etc. But in most of Europe and North America macro algae as a food, is a very new food trend. These days, when we are talking about macro algae as food, we are not talking about some kind of exotic and expensive food staffs rather we are talking in a way we used to talk about dairy products. In fact macro algae are much more abundant and available for food than dairy products, but many Americans, Europeans, Africans, Asians and Australians have always considered foods related with macroalgae as exotic and expensive. But in reality most of us have consumed food products that contain macroalgae every day without even knowing it. Many food industries use macroalgae in their food products starting from sushi, bakery, beverages, ice creams, salad dressings, meat preservatives, poultry products, desserts, sauces, soy milks, pancake syrup, fruit juice, peanut butter, tomato sauce, pasta products, confectioneries etc. the list is ever expanding. Macroalgae are divided in to three groups these are red macro algae or rhodophyta, green macroalgae or chlorophyta and brown macroalgae or pheophyta. Macroalgae produce a very valuable gelling substances for the food industry, which are used as a gelling agent or thickening agent. These gelling substances are called phycocolloids. Phycocolloids are produced only by the red macroalgae and the brown macroalgae. Red macroalgae produce two types of phycocolloids called agar and carrageenan. And brown macroalgae produces a phycocolloids called alginate. Following are some of the uses of macroalgae in food related staffs.

Norri is the most popular macroalgae used in sushi as wrapping. Nori is a red macroalgae from the species of Porphyra. When you see sushi there is Nori. In addition to its use as sushi wrapping, Nori also uses as a major ingredient in soups, vegetable, salads and health food stores.

Carrageenan is very popular red macroalgae belonging to the species of Chondrus crispus and Gigartina stellata. Carrageenan contains the polysaccharide carrageenan, which is a gelatinous substance or phycocolloid used as a thickening agent in bakery products, ice creams, soups, fruit juices, soy milks, confectioneries, tinned, dairy products, soft drinks, pet foods, brewing etc. So next time if you wonder what makes an ice cream so creamy and attractive the answer is carrageenan.

Agar is another very popular phycocolloids, mainly used as a culture medium in laboratories. But it is also used by food industries as a thickening and gelling agent. Agar is produced mainly by the red macroalgae species such as Gelidium and Gracilaria. Agar is increasingly used in tinned, bakery, confectioneries, icecreams and frozen food products.

Alginate is also another very popular phycocolloids, produced only by brown macroalgae species. Food industries use alginate in various tinned, dairy products, bakery products, glassed foods, salad dressings, frozen foods, non carbonated beverages, brewing etc.