title: Mechanical α-relaxations and stickiness of milk solids/maltodextrin systems around glass transition.
abstract: BACKGROUND
  Stickiness correlates with changes in mechanical α-relaxation properties and often results from glass transition and plasticisation of amorphous food components. In this study, milk solids with maltodextrins with different dextrose equivalents (DE9 and DE17) were analysed for glass transition (T(g) ), α-relaxation (T(α) ) and sticky point (SPT) temperatures using differential scanning calorimetry, dynamic mechanical analysis and a sticky point test respectively.
  
  
  RESULTS
  At the same maltodextrin contents, T(g) and T(α) were lower for milk solids with the higher-DE maltodextrin. Increasing maltodextrin contents gave T(g) , T(α) and SPT at higher temperatures, and the magnitudes of α-relaxations with high maltodextrin (DE9 and DE17) contents were less pronounced.
  
  
  CONCLUSIONS
  Stickiness was governed by glass transition and affected by skim milk/maltodextrin composition. Stickiness was reduced with increasing maltodextrin content as a result of maltodextrin miscibility with skim milk solids, particularly lactose, which changed the relaxation behaviour above the glass transition. The mixes of milk solids with low-DE maltodextrin may show improved dehydration characteristics and powder stability resulting from increased T(g) , T(α) and SPT.
authors: School of Food and Nutritional Sciences, University College Cork, Cork, Ireland.
authors: Nattiga
authors: N
authors: Silalai
authors: Yrjö H
authors: YH
authors: Roos
mesh_terms: D000268:Adhesiveness; D002152:Calorimetry, Differential Scanning; D002241:Carbohydrates / Q000737:chemistry; D055598:Chemical Phenomena; D003611:Dairy Products / Q000032:analysis*; D004040:Dietary Carbohydrates / Q000032:analysis; D055119:Elastic Modulus; D005503:Food Additives / Q000737:chemistry*; D057141:Food, Preserved / Q000032:analysis*; D055595:Mechanical Phenomena; D008894:Milk Proteins / Q000737:chemistry; D044367:Phase Transition; D011134:Polysaccharides / Q000737:chemistry*; D012995:Solubility; D044366:Transition Temperature; D014783:Viscosity; D014867:Water / Q000032:analysis
chemical_list: D002241:Carbohydrates; D004040:Dietary Carbohydrates; D005503:Food Additives; D008894:Milk Proteins; D011134:Polysaccharides; D014867:Water; C008315:maltodextrin