Whey Strawberry Rolls

Directions

1. 1
   Sift the flour and baking powder together in a mixing bowl. Line a 30x40-cm baking tray with parchment paper. Preheat oven to 175C/350F.
2. 2
   In another bowl, place together the whey, strawberry icing powder and corn oil. Whisk until the mixture is emulsified. Sift in flour mixture and blend until just combined. Add in egg yolks and fold until smooth.
3. 3
   Beat egg whites with salt and lemon juice over low speed until frothy and foamy. Gradually add in sugar, increase speed and beat until stiff but not dry. Carefully fold 1/3 of egg white mixture into flour mixture to lighten it and then carefully fold in remaining whites.
4. 4
   Pour the cake batter into the prepared baking tray and spread the surface even. Bake for 15 minutes. Remove, cool briefly, and invert the cake onto a new parchment paper. Carefully peel off the the paper liner and then invert again the baked side-up to cool on a wire rack. Trim the edges of cake. Spread the surface with whipped cream and roll it up. Chill for about 1 hour and slice.