Physics:Bloom (test)

From HandWiki
Short description: Test to measure strength of a gel


Bloom is a test used to measure the strength of a gel, most commonly gelatin. The test was originally developed and patented in 1925 by Oscar T. Bloom.[1] The test determines the weight in grams needed by a specified plunger (normally with a diameter of 0.5 inch) to depress the surface of the gel by 4 mm without breaking it at a specified temperature.[2] The number of grams is called the Bloom value, and most gelatins are between 30 and 300 g Bloom. The higher a Bloom value, the higher the melting and gelling points of a gel, and the shorter its gelling times.[2] This method is most often used on soft gelatin capsules ("softgels"). To perform the Bloom test on gelatin, a 6.67% gelatin solution is kept for 17–18 hours at 10 °C prior to being tested.

Various gelatins are categorized as "low Bloom", "medium Bloom", or "high Bloom", but there are not universally defined specific values for these subranges. Gelatin is a biopolymer material composed of polypeptide chains of varying length. The longer the chain, the higher the Bloom number:[3]

Gelatin classes
Category Bloom number (Bloom strength) Average molecular mass Examples
Low Bloom 30–150[4] 20,000–25,000 Beef hide low Bloom gelatin (USP-NF)[5]
Medium Bloom 150–225 40,000–50,000 Gelatin type B[6]
High Bloom 225–325 50,000–100,000 Gelatin type A[6]

See also

  • Durometer

References

  1. "US1540979 Machine for testing jelly strength of glues, gelatins, and the like". https://www.google.com/patents/US1540979. Retrieved 1 September 2016. 
  2. 2.0 2.1 Schrieber, Reinhard; Gareis, Herbert (27 June 2007). Gelatine Handbook: Theory and Industrial Practice. Wiley. ISBN 978-3-527-61097-6. 
  3. "Gelatins—product information sheet". Sigma-Aldrich. https://www.sigmaaldrich.com/content/dam/sigma-aldrich/docs/Sigma/Product_Information_Sheet/2/g9382pis.pdf. Retrieved 2017-08-24. 
  4. "Gelatin - an overview | ScienceDirect Topics". https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/gelatin#:~:text=Gel%20strength,%20also%20known%20as,%E2%80%93300%20a%20high%20bloom).. Link to original publication
  5. "GELATIN - LOW BLOOM - BEEF-HIDE - NF by Vyse Gelatin Company - Food, Beverage & Nutrition". https://www.ulprospector.com/en/na/Food/Detail/3844/109618/GELATIN---LOW-BLOOM---BEEF-HIDE---NF#:~:text=Gelatin%20-%20Low%20Bloom%20-%20Beef-Hide%20-,a%20pH%20level%20of%205.60%20+%200.60.. 
  6. 6.0 6.1 Felix, Pascal G. (2003-11-18). Characterization and correlation analysis of pharmaceutical gelatin (Thesis). Digital Commons @ University of South Florida. Archived from the original on 2023-12-15. Retrieved 2023-12-15.

External links

  • Phillips, Glyn O.; Williams, Peter A. (2000). Handbook of Hydrocolloids. Taylor & Francis. ISBN 9780849308505.