question: Why is blood at grocery stores a liquid? Why hasn't it coagulated?
comment: They remove the Platelets (Coagulating Agent) from the Plasma before putting it on the Market. They don't add anything to the taste, so there's no reason to keep them. Then you just keep the blood cold and prevent it from contacting air and you're golden. It wouldn't be able to function inside of the animal anymore, mind you. But it tastes just fine.
passages: In hemoperfusion, the blood perfuses a filter composed of artificial cells filled with activated carbon or another microporous material. Small molecules in solution within the serum (such as the toxin) cross the membranes into the microporous material (and get trapped therein), but formed elements (the blood cells) brush past the artificial cells just as they brush past each other. In this way, the microporous material's filtering ability can be used without destroying the blood cells.
   BULLET::::- If 'negative', the plasma remains a liquid. The negative result may be "S. epidermidis" but only a more detailed identification test can confirm this, using biochemical tests as in analytical profile index tests methods. A false negative can be perceived if the sample is not allowed to cool for about 30 minutes at room temperature or 10 minutes in the freezer, given that the serum can melt. If truly negative, the serum will remain liquid after cooling.
   Blood is a complex liquid. Blood is composed of plasma and formed elements. The plasma contains 91.5% water, 7% proteins and 1.5% other solutes. The formed elements are platelets, white blood cells and red blood cells, the presence of these formed elements and their interaction with plasma molecules are the main reasons why blood differs so much from ideal Newtonian fluids.
  
  Section::::Blood.:Viscosity of plasma.
   Whole blood (plasma and cells) exhibits non-Newtonian fluid dynamics. If all human hemoglobin were free in the plasma rather than being contained in RBCs, the circulatory fluid would be too viscous for the cardiovascular system to function effectively.
  
  Section::::Constituents.:In mammals.:Cells.
  
  One microliter of blood contains:
   BULLET::::- Leukocyte reduction is the removal of white blood cells by filtration. Leukoreduced blood products are less likely to cause HLA alloimmunization (development of antibodies against specific blood types), febrile non-hemolytic transfusion reaction, cytomegalovirus infection, and platelet-transfusion refractoriness.
   Although it was hard to make chromatographic processing methods widely adopted, global expansion is a work in progress. Various blood components must be readily available at various medical treatment centers around the world. The Institute of Transfusion Medicine in Skopje, Macedonia is a plasma fractionation center in the Balkans. Their modernized albumin purification process consists of five steps:
  
  BULLET::::1. Starting material is plasma that has been pretreated by centrifugation,
  
  BULLET::::2. A round of gel filtration is run,
  
  BULLET::::3. ion exchange on DEAE Sepharose is run to bind the albumin to the column,
   BULLET::::- Reduced cost: fetal calf serum can account for up to 85% of the overall cost of the medium when calculated for large-scale cultures.
  
  BULLET::::- There are increasing concerns about animal suffering inflicted during serum collection that add an ethical imperative to move away from the use of serum wherever possible.
  
  Chemically defined media also allows researchers who are studying in the field of cell physiology (especially extracellular) and or molecule–cell interactions to eliminate any variables that may arise due to the effects of unknown components in the medium. 
  
  Section::::Classes of media.
   Blood is the most important byproduct of slaughtering. It consists predominantly of protein and water, and is sometimes called "liquid meat" because its composition is similar to that of lean meat. Blood collected hygienically can be used for human consumption, otherwise it is converted to blood meal. Special fractions of animal blood are used in human medicine.
  
  Section::::Methods of preparation.
  
  Section::::Methods of preparation.:Sausage.
   The Chinese hamster ovary cells that were stably transfected produced significant quantities of Factor IX, which was shown to have substantial coagulant properties, though of a lesser degree than Factor IX produced from human blood:The specific activity of the recombinant Factor IX was measured on the basis of direct measurement of the coagulant activity... The specific activity of recombinant Factor IX was 75 units/mg... compared to 150 units/mg measured for plasma-derived Factor IX...
   BULLET::::- "Mycoplasma bovis": 0.06 - 4 μg/ml
  
  BULLET::::- "Staphylococcus aureus": 0.5 - 128 μg/ml
  
  Section::::Clinical use.
   The less-dense blood plasma is made into a variety of frozen components, and is labeled differently based on when it was frozen and what the intended use of the product is. If the plasma is frozen promptly and is intended for transfusion, it is typically labeled as fresh frozen plasma. If it is intended to be made into other products, it is typically labeled as recovered plasma or plasma for fractionation. Cryoprecipitate can be made from other plasma components. These components must be stored at or colder, but are typically stored at . The layer between the red cells and the plasma is referred to as the buffy coat and is sometimes removed to make platelets for transfusion. Platelets are typically pooled before transfusion and have a shelf life of 5 to 7 days, or 3 days once the facility that collected them has completed their tests. Platelets are stored at room temperature () and must be rocked/agitated. Since they are stored at room temperature in nutritive solutions, they are at relatively high risk for growing bacteria.
   Coagulated chicken, duck, goose or pig blood is used in soups, such as the classic Thai dish "Tom Lued Moo" (pork blood soup). Thailand also has a dish known as "Nam Tok", which is a spicy soup stock enriched with raw cow or pig's blood. It is often used to enrich regular noodle dishes, as well as in Khao soi.
   Blood can also be used as a solid ingredient, either by allowing it to congeal before use, or by cooking it to accelerate the process. Blood curd is a dish typically found in Asia that consists of cooled and hardened animal blood.
   Many forms of medication (from antibiotics to chemotherapy) are administered intravenously, as they are not readily or adequately absorbed by the digestive tract.
  
  After severe acute blood loss, liquid preparations, generically known as plasma expanders, can be given intravenously, either solutions of salts (NaCl, KCl, CaCl etc.) at physiological concentrations, or colloidal solutions, such as dextrans, human serum albumin, or fresh frozen plasma. In these emergency situations, a plasma expander is a more effective life-saving procedure than a blood transfusion, because the metabolism of transfused red blood cells does not restart immediately after a transfusion.
  
  Section::::Treatments.:Bloodletting.
   Blood soups and stews, which use blood as part of the broth, include czernina, dinuguan, haejangguk, mykyrokka, pig's organ soup, tiet canh and svartsoppa.
  
  Blood is also used as a thickener in sauces, such as coq au vin or pressed duck, and puddings, such as tiết canh. It can provide flavor or color for meat, as in cabidela.
  
  Section::::Methods of preparation.:Solidified.
   Some blood banks also collect products by apheresis. The most common component collected is plasma via plasmapheresis, but red blood cells and platelets can be collected by similar methods. These products generally have the same shelf life and storage conditions as their conventionally-produced counterparts.
  
  Donors are sometimes paid; in the U.S. and Europe, most blood "for transfusion" is collected from volunteers while plasma for other purposes may be from paid donors.
   Blood product
  
  A blood product is any therapeutic substance prepared from human blood. This includes: whole blood; blood components; and plasma derivatives. Whole blood is not commonly used in transfusion medicine. Blood components include: red blood cell concentrates or suspensions; platelets produced from whole blood or via apheresis; plasma; and cryoprecipitate. Plasma derivatives are plasma proteins prepared under pharmaceutical manufacturing conditions, these include: albumin; coagulation factor concentrates; and immunoglobulins.
  
  Section::::Relation to other substances.
   PolyHeme was developed over 20 years by Northfield Laboratories and began as a military project following the Vietnam War. It is human haemoglobin, extracted from red blood cells, then polymerized, then incorporated into an electrolyte solution. In April 2009, the FDA rejected Northfield's Biologic License Application and in June 2009, Northfield filed for bankruptcy.
  
  Dextran-Haemoglobin was developed by Dextro-Sang Corp as a veterinary product, and was a conjugate of the polymer dextran with human haemoglobin.
  
  Hemotech was developed by HemoBiotech and was a chemically modified haemoglobin.
   Section::::History.
  
  The Blood Products Laboratory was established in 1954 as part of the Lister Institute of Preventive Medicine by the Medical Research Council. Lister purchased the Elstree site in 1902 and operated on the site until 1978.
  
  During this time, Professor R. A.Kekwick, working at the Lister Institute undertook experimental and production work with A.S. McFarlane. The two scientists devised a process to clarify outdated blood plasma to render it suitable for transfusion. Laboratory testing was undertaken in the historic Queensbury Lodge, the site of Joseph Lister's laboratory.
   Normal blood plasma behaves like a Newtonian fluid at physiological rates of shear. Typical values for the viscosity of normal human plasma at 37 °C is 1.4 mN·s/m. The viscosity of normal plasma varies with temperature in the same way as does that of its solvent water; a 5 °C increase of temperature in the physiological range reduces plasma viscosity by about 10%.
  
  Section::::Blood.:Osmotic pressure of plasma.
   The tube test uses rabbit plasma that has been inoculated with a staphylococcal colony (i.e., Gram-positive cocci which are catalase positive). The tube is then incubated at 37 °C for 1.5 hours. If negative, then incubation is continued up to 18 hours. 
  
  BULLET::::- If 'positive' (e.g., the suspect colony is "S. aureus"), the plasma will coagulate, resulting in a clot (sometimes the clot is so pronounced, the liquid will completely solidify).
   BULLET::::4. Albumin is eluted with a sodium acetate buffer, and
  
  BULLET::::5. Final polishing with gel filtration.
  
  The end result is a highly pure and safe batch of albumin that is 100% non-pyrogenic, sterile, and free of active HIV virus. The product purity is greater than 98% and the protein content is about 50 g/L.
  
  Section::::Non-chromatographic processing methods.
  
  Other plasma processing methods exist, but generally do not provide the resolution or purity of chromatographic methods. 
   , there were about 15 million units of blood products transfused per year in the United States. By 2013, the number had declined to about 11 million units, because of the shift towards laparoscopic surgery and other surgical advances and studies that have shown that many transfusions were unnecessary. For example, the standard of care reduced that amount of blood transfused from 750 to 200 ml.
  
  Section::::Special populations.
  
  Section::::Special populations.:Neonate.
   The collected blood is generally separated into components by one of three methods. A centrifuge can be used in a "hard spin" which separates whole blood into plasma and red cells or for a "soft spin" which separates it into plasma, buffy coat (used to make platelets), and red blood cells. The third method is sedimentation: the blood simply sits overnight and the red cells and plasma are separated by gravitational interactions.
  
  Section::::Storage.
   Despite measures that are in place in the developed world to ensure the safety of blood products for transfusion, a risk of disease transmission still exists. Consequently, the development of pathogen inactivation/reduction technologies for blood products has been an ongoing effort in the field of transfusion medicine. A new procedure for the treatment of individual units of single-donor (apheresis) or whole blood–derived, pooled, platelets has recently been introduced. This technology uses riboflavin and light for the treatment of platelets and plasma.
  
  Section::::Method.
  
raw_presuppositions: Blood sold in grocery stores still has platelets to coagulate. 
raw_corrections: Blood sold in grocery stores already has the platelets removed.