title: Effects of buttermilk powders on emulsification properties and acid tolerance of cream.
abstract: Emulsifying properties and acid tolerance are 2 of the most important characteristics of cream. The effects of the buttermilk component, especially its phospholipids, on the emulsifying properties and acid tolerance of cream were investigated in this study. Two buttermilks with differing phospholipid contents and skimmed milk were used to evaluate the effects of phospholipids on the aforementioned parameters. The mean diameter of fat globules and the cream viscosity were used as indicators of emulsifying properties. Acid tolerance was evaluated by studying the effect of citric acid on the maximum viscosity of cream. This was tested by adding 400 μL of 10% (w/w) citric acid solution to cream every minute and simultaneously measuring pH and viscosity. In 45% and 40% fat cream systems, buttermilk, and especially that with higher phospholipid content, improved the emulsifying properties and acid tolerance of the cream. The components of buttermilk could alter the properties of the surface of fat globules, thereby altering the emulsification properties of the cream. However, neither of the tested buttermilks affected the emulsifying properties and acid tolerance of lower-fat (35% and 30%) cream systems. Emulsifying components exist in proportionately larger amounts in lower-fat creams, which could render the emulsifying properties resistant to change. The number of fat globules may also influence acid-induced changes in viscosity. The addition of phospholipids or lysophospholipids did not improve the acid tolerance of creams, a finding that may be attributable to the formation of complexes of phospholipids and protein.
  
  
  CONCLUSIONS
  The findings presented herein demonstrate the ability to improve the acid tolerance of cream using materials derived from milk. Implementing these findings appropriately may result in a high-quality cooking cream.
authors.affiliation: Food Science & Food Technology Inst, 1-83, 5-Chome Higashihara, Zama, Kanagawa 252-8583, Japan. k_ihara@morinagamilk.co.jp
authors.forename: Keiichi
authors.initials: K
authors.lastname: Ihara
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ochi
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Saito
authors.forename: Keiji
authors.initials: K
authors.lastname: Iwatsuki
mesh_terms: D000143:Acids / Q000032:analysis; D000818:Animals; D055598:Chemical Phenomena; D043302:Cultured Milk Products / Q000737:chemistry* / Q000378:metabolism; D045703:Emulsifying Agents / Q000737:chemistry*; D004655:Emulsions; D005511:Food Handling / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008894:Milk Proteins / Q000032:analysis / Q000378:metabolism; D010743:Phospholipids / Q000032:analysis / Q000378:metabolism; D011208:Powders / Q000737:chemistry* / Q000378:metabolism; D014783:Viscosity
chemical_list: D000143:Acids; D045703:Emulsifying Agents; D004655:Emulsions; D008894:Milk Proteins; D010743:Phospholipids; D011208:Powders