A feasibility study on the pilot scale manufacture of fresh cheese from skim milk retentates without acid whey production: Effect of calcium content on bitterness and texture

The sensory and structural properties of fresh cheeses (8.0%, w/w, protein) made from fermented skim milk retentates [concentrated-fermented (CoF) fresh cheese] with different calcium-protein ratios (Ca:Prot; 15.9–36.6 mg g ⁻¹ ) by means of pilot plant scale microfiltration (MF) and MF in the diafiltration (DF) mode without acid whey (AW) production were characterised. Calcium reduction reduced the bitterness level significantly (by 53.4%) and the bitter peptide content (by ≈33%) of the CoF fresh cheese after ≤ 1 week of storage; however, storage for ≥ 2 weeks resulted in an increase of both bitterness and bitter peptide content, and quantitatively changed the peptide pattern, possibly due to lack of thermisation. Fresh cheese with a lower bitterness level can be successfully manufactured, while avoiding AW production, if the Ca:Prot of the milk retentate is decreased to ≤15.9 mg g ⁻¹ (calcium content = 1240 mg kg ⁻¹ at 7.81%, w/w, protein) prior to fermentation.