• Development and Evaluation of Caseins/Caseinates for use as Ingredients in Food Products

      Mehra, Raj; Walsh, Daniel; O'Kennedy, Brendan; Kelly, Phil (Teagasc, 1998-09-01)
      The overall objective of this project was to investigate the effects of key processing steps in the industrial production of acid casein on the characteristics and functionality of sodium caseinate with particular emphasis on analytical/functionality testing and seasonal/lactational effects on the original milk. The main conclusions were as follows: The most significant result indicates that drying and concentration after washing of the acid casein curd are responsible for alterations in the structure of casein, which result in sodium caseinates with different properties. This was confirmed in the case of two acid casein plants investigated which showed similar results even though using different washing and drying technologies. This difference due to the drying step may be further amplified depending upon whether commercial sodium caseinate is manufactured from acid casein in the dried or wet curd state. The analytical and functional testing methodology adapted in our laboratory proved effective in predicting the effects of processing steps on the functionality of sodium caseinate. In particular, the ability to detect the presence of aggregate formation was particularly important. The database generated subsequently helped an acid casein manufacturer in modifying its process(es) to manufacture experimental sodium caseinate for specific food end-uses. Progress was greatly facilitated by the collaboration of individual manufacturers in the sourcing of problem samples from previously manufactured codes, and facilitating access to process plant during production. In a commercial application of the database, confidential work was undertaken on behalf of a client. Experimentally-produced sodium caseinate ingredients were evaluated using our adapted functionality testing methods and based on the results, the company was able to modify its process(es) to produce sodium caseinates with functionality for specific food end-users. It was concluded that while processing parameters in the production of acid casein can have a significant effect on the functional behaviour of the resultant sodium caseinate, the ability to assess this change in functional behaviour, through relevant functional testing, was equally important.