Influence of denatured whey proteins recovered from ras cheese whey on the rheological characteristics of dough and quality of croissant

الملخص EN

Denatured Whey Proteins (DWP) were recovered from Ras cheese whey and examined for physiochemical, microbiological and functional properties.

The prepared DWP was utilized for substituting dried milk powder in croissant making at levels of 50% and 100% as well as 100% associated with one fourth butter reduction.

Rheological properties of the croissant dough treatments were determined by farinograph and extensograph.

Physical characteristics, chemical analysis and colour measurements of croissant were also determined.

Compressibility, staling and sensory evaluation of product were periodically measured through 7 days storage at room temperature.

The total solids of the recovered DWP reached up to 28.44 % with a protein content of 19.88 %.

Besides, carrying out the recovery process at 90 °C /10 min resulted in significant improvement of DWP safety.

Neither Staphylococcus areus, Salmonella sp.

total coliforms or yeast & molds were detected.

Generally, foaming capacity values of DWP were much lower at pH 4.5 than at pH 8.5, while the oil absorption capacity was higher than the water absorption capacity.

The water absorption and extensibility of wheat flour dough were decreased with increase in the levels of denatured whey protein.

Croissant samples made with DWP had high moisture and ash content than those untreated with DWP.

The incorporation of whey protein resulted in paler crust colour.

After 3 days of storage, the croissant made with 100% DWP substitution showed higher compressibility values compared with other tested samples.

In general, panelists preferred croissant with 100% substitution as well as control sample.

Croissants prepared with 100% denatured whey protein and 100% substitution with one fourth butter reduction reduced the total cost by 11.31 and 26.49%, respectively as compared with the control one.