Dissolve gelatin in boiling water; add cold water, juice and peel.
Combine neufchatel cheese and sugar, mixing until well blended.
Gradually add gelatin mixture to neufchatel cheese mixture, mixing until blended.
Chill, stirring occasionally, until thickened but not set.
Beat with electric mixer until fluffy.
Spoon into individual parfait glasses; chill several hours or overnight.