Essay on Yogurt Essay on Yogurt Yogurt sell in Marzhe was slimy and with curds formed in it and it's containers were bloated with noticeably swelling at the lid. Yogurt spoilage is usually causes by high pH value intrinsic factor and temperature extrinsic factor. Yogurt, one of the fermented milk products, is made by inoculating certain bacteria starter cultureusually Streptococcus thermophilus and Lactobacillus bulgaricus, into milk.
Yoghurt and Other Fermented Milks Microbiology Article Shared by In this article we will discuss about fermentation process of yoghurt and other fermented milks. Fermentation Process of Yoghurt: Fermentation to extend the useful life of milk is probably as old as dairying itself. The first animals to be domesticated are thought to have been goats and sheep in the Near East in about BC.
In the warm prevailing climate it is likely that their milks furnished the first fermented milks and only some time later, between and BC in Turkey or Macedonia, was the cow first domesticated. Fermented milks which include yoghurt, buttermilk, sour cream, and kefir differ from cheese in that rennet is not used and the thickening produced is the result of acidification by lactic acid bacteria.
It is made from milk, skimmed milk or fortified milk usually from cows but sometimes from other animals such as goats or sheep. The production process most commonly applied commercially is outlined in Figure 9. The first prerequisite of any milk to be used in a fermentation process is that it should be free from antimicrobials.
These could be antibiotic residues secreted in the milk as a result of mastitis chemotherapy or sanitizers carried into the milk as a result of inadequate equipment cleaning regimes at the farm or dairy. Inhibition of the starter culture would result not only in economic losses but could potentially allow pathogens to grow.
In commercial practice it is usual to supplement the solids content of the milk to enhance the final texture of the product. The simplest way of achieving this is by addition of skim- or whole-milk powder depending on whether a conventional or low-fat product is required.
The properties of the product may also be improved and stabilized by the addition of small amounts of natural or modified gums which bind water and thicken the product.
If left to stand, the milk fat would separate out to form a cream layer. Being well in excess of the normal pasteurization requirements for safety, this has a substantial lethal effect on the microflora. All but heat-resistant spores are eliminated so that the starter culture encounters little by way of competition.
|2 Colostrum Vs Milk||In this article we will discuss about:|
|Fermented Milk - an overview | ScienceDirect Topics||Hire Writer The chief constructions in the liquid part of the milk are micelles of casein protein: Each micelle formed by casein proteins is about spherical.|
Excessive heating can however lead to the production of inhibitory levels of these compounds. Heating also promotes interactions between whey or serum proteins and casein which increase the yoghurt viscosity, stabilize the gel and limit syneresis separation of whey.
The fermentation can be conducted in the retail pack to produce a firm, continuous coagulum, which is known as a set yoghurt, or in bulk tanks to produce a stirred yoghurt where the gel has been broken by mixing in other ingredients and by pumping into packs.
The fermentation takes about 4 h during which the starter bacteria ferment lactose to lactic acid decreasing the pH from its initial level of 6. The lactic acid helps solubilize calcium and phosphate ions which destabilize the complex of casein micelles and denatured whey proteins.
When the pH reaches 4. During fermentation growth of the streptococci is fastest in the early stages, but as the pH drops below 5. By the end of fermentation the product has a total acidity of 0. The relationship between the two starter organisms is one known as pro-to-cooperation, that is to say they have a mutually favourable interaction but are not completely interdependent.
Both will grow on their own in milk but will grow and acidify the product faster when present together. The lactobacillus is slightly proteolytic and liberates small amounts of these, particularly valine, which stimulate streptococcal growth.
In its turn the streptococcus produces formate, pyruvate and carbon dioxide all of which stimulate the lactobacillus.Yogurt, one of the fermented milk products, is made by inoculating certain bacteria (starter culture), usually Streptococcus thermophilus and Lactobacillus bulgaricus, into milk.
After the milk is incubated at approximately C for 2 to 3 hours or until firm; the milk is coagulated by bacteria-produced lactic acid. Biopreservation The Food Preservation Biology Essay Biopreservation entails the preservation of food and food products utilising biological substances (Caplice and Fitzgerald, ).
It refers to the extension of the shelf-life and the improvement of the safety of foods using microorganisms and/or their metabolites or fermentation products . The Role of Lactic Acid Bacteria in Milk Fermentation Yantyati Widyastuti1, Rohmatussolihat1, fermented milk products such as yoghurt and cheese.
Preservative Property of Lactic Acid Acidification of the milk protects the milk against spoilage microorganisms and proliferation of. Yoghurt and Other Fermented Milks | Microbiology.
Article Shared by. ADVERTISEMENTS: In this article we will discuss about fermentation process of yoghurt and other fermented milks. Diacetyl, an important flavour compound in many dairy products, is present at very low levels.
Spoilage microorganisms in milk and dairy products. pasteurized and sterilized milk, fermented milk, butter, sour cream and cheeses with the intention to emphasize the importance and.
The major concern of the meat safety is microbic spoilage. The beginnings of microbic taint are perchance coming from the slaughter animals themselves, the procedure workers, and the processing environment (1).
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