title: Effect of dairy powder rehydration state on gel formation during yogurt process.
abstract: Protein fortification and solubilisation into the milk base are important parameters enhancing yogurt texture. In this study, the milk base prepared from reconstituted skim milk powder was fortified with 2% of 'aged' (1 year old) or 'fresh' micellar casein (MC) powder. Micellar casein powders were left to rehydrate at 20°C for different times (5 or 180, 300, 480, 900 or 1440 min) before acidification with glucono-delta-lactone. The rehydration of the MC powders into milk was monitored with a granulo-morphometer equipment, thus, for the first time, allowing the elucidation of MC rehydration process into an opaque environment such as milk. Whereas the gel point was delayed proportionally to the powder rehydration length, the storage modulus appears unaffected. Besides, the gelation onset was not altered by the powder age.
authors.affiliation: Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, 2 avenue de la Forêt de Haye, BP 172, 54505 Vandoeuvre-lès-Nancy, France.
authors.forename: Marie Celeste
authors.initials: MC
authors.lastname: Karam
authors.forename: Claire
authors.initials: C
authors.lastname: Gaiani
authors.forename: Reine
authors.initials: R
authors.lastname: Barbar
authors.forename: Chadi
authors.initials: C
authors.lastname: Hosri
authors.forename: Joel
authors.initials: J
authors.lastname: Scher
mesh_terms: D000818:Animals; D002364:Caseins / Q000737:chemistry; D005527:Food, Fortified / Q000032:analysis; D057141:Food, Preserved; D005782:Gels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D008892:Milk / Q000737:chemistry*; D008894:Milk Proteins / Q000032:analysis; D010316:Particle Size; D012212:Rheology; D012995:Solubility; D014867:Water; D015014:Yogurt / Q000032:analysis*
chemical_list: D002364:Caseins; D005782:Gels; D008823:Micelles; D008894:Milk Proteins; D014867:Water