Frozen Storage is Detrimental to the Functionality of Cream Cheese and Mascarpone even in High Pressure Treated Samples

Abstract

Cream cheese and Mascarpone are two popular types of fresh cheeses. In the US, these cheeses have recently experienced growth in their exports due to their popularity in baking and dessert applications (e.g., cheesecake and tiramisu). Historically, these products were consumed quickly, but the introduction of processing methods like hot packing (where the hot product is filled directly into the final containers) has facilitated a much longer shelf life. Freezing is a widely used approach to extend the shelf life of cheeses like low moisture part-skim Mozzarella, but to our knowledge it is not used for many fresh cheeses. The high moisture and low protein contents of these fresh cheeses could increase the risk that the freezing process could damage the protein matrix. We investigated the impact of various storage temperatures on the texture, rheological properties, as well as functionality in key food applications, of these two types of fresh cheeses. The freezing point of cream cheese and Mascarpone has not been published but we considered that it should be <0°C, and that temperatures around 0°C may be considered a type of superchilling (or use of very low refrigeration temperatures). We obtained commercially manufactured cream and Mascarpone cheeses one week after manufacture and then stored cheeses at 4°C, 0°C, or 18°C for 450 d. Yeast and molds can limit the shelf life of fresh cheeses. High pressure processing (HPP) can easily inactivate yeasts and molds, so we also tested the impact of HPP (after packaging) on the properties of these cheeses that were part of the temperature trials. Both types of cheese held at 18°C exhibited a reduction in firmness during storage. There was no significant change in firmness for both cheese samples when stored at 4 or 0°C. A grainy texture was observed in the frozen cream cheese samples, HPP treatment slightly improved the graininess. Cracks and a brittle body were observed in the frozen mascarpone cheese samples, which appeared smoother with HPP treatment. Cheesecakes made with frozen cream cheese samples were weaker than cheeses stored at 4 or 0°C, which hardly changed in hardness during the storage period. Similar trends for cheesecake hardness were seen in HPP treated cheeses. We evaluated the yield stress of foams prepared from tiramisu desserts made with Mascarpone cheese. Frozen storage reduced the yield stress of tiramisu foams; yield stress of foams made from the Mascarpone cheeses stored at 4 or 0°C hardly changed during the storage period. The freezing points of cream cheese and Mascarpone were determined by differential scanning calorimetry to be approximately -8°C and -2°C, respectively. Frozen storage was highly detrimental to the texture and functionality of both cream cheese and Mascarpone and should be avoided.