Team:HIT-Harbin/Project

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Contents

Overview


The project

I have a dream
I am happy to join with you today in what will go down in history as the greatest demonstration for freedom in the history of our nation.

Five score years ago, a great American, in whose symbolic shadow we stand today, signed the Emancipation Proclamation. This Momentous decree came as a great beacon light of hope to millions of Negro slaves who had been seared in the flames of withering injustice. It came as a joyous daybreak to end the long night of their captivity.

But one hundred years later, the Negro still is not free. One hundred years later, the life of the Negro is still sadly crippled by the manacles of segregation and the chains of discrimination. One hundred years later, the Negro lives on a lonely island of poverty in the midst of a vast ocean of material prosperity. One hundred years later, the Negro is still languishing in the corners of American society and finds himself an exile in his own land. So we have come here today to dramatize the shameful condition.

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Background


Yogurt is manufactured using a culture of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus salivarius subsp. thermophilus bacteria. This fermented product is nutritionally rich in protein, calcium, riboflavin, vitamin B6 and vitamin B12[1]. In addition, consumers who are moderately lactose-intolerant can consume yoghurt without ill symptoms, because much of the lactose in the milk precursor is converted to lactic acid by the bacterial culture[2]. Yoghurt containing live cultures is sometimes used in an attempt to prevent antibiotic-associated diarrhea. Yoghurt contains varying amounts of fat. There is non-fat (<0.5% fat), low-fat (usually 2% fat) and plain or whole milk yoghurt (4% fat). A study published in the International Journal of Obesity also found that the consumption of low-fat yoghurt can promote weight loss, mainly due to the abundance of calcium in the yogurt[3].


About post-acidification

Although yogurt possesses many health benefits there exists a major problem in yogurt manufacturing and during storage prior to consumption, i.e., post-acidification. As bioactive ingredients, Lactobacillus bulgaricus and Streptococcus thermophilus continue to produce lactic acid after production fermentation, making the yogurt too sour. This phenomenon is not desirable. Post-acidification shortens yogurt’s shelf life results in an unacceptable taste by consumers. Therefore, the objective of this project is to minimize post-acidification in yogurt achieving a consistent acidity (pH) and a prolonged shelf-life.


About collagen

Collagen is well known to consumers, especially to female consumers. Collagen is one of the long, fibrous structural proteins, whose functions are quite different from those of globular proteins such as enzymes. Tough bundles of collagen called collagen fibers are a major component of the extracellular matrix that supports most tissues and gives cells structure from the outside. Collagen is also found inside certain cells. Collagen has great tensile strength and is the main component of fascia, cartilage, ligaments, tendons, bone and skin[4]. Along with soft keratin, it is responsible for skin strength and elasticity, and its degradation leads to wrinkles with aging. It strengthens blood vessels and plays an important role in tissue development. It is present in the cornea and lens of the eye in crystalline form. Hydrolyzed collagen can also play an important role in weight management, as a protein, it can be advantageously used for its satiating power. Thus it is of great interest in producing a yogurt rich in collagen.

Outline

Conclusion

References