Preserving the ‘stretch’ of frozen mozzarella cheese

The diversification of mozzarella

The origins of mozzarella can be traced back to a small region in Southern Italy, where mozzarella is traditionally prepared using buffalo’s milk. The market for mozzarella remained relatively limited and started to expand worldwide because of the growing popularity for Italian cuisine. Nowadays, several types of mozzarella cheese can be distinguished (Kindstedt, 2004). The most well-known mozzarella cheese is the fresh variant, which has a high moisture content (> 52% moisture) and can be store-bought in packages filled with brine. This mozzarella variant is usually consumed fresh as a table-cheese with tomato and bread. In contrast, low-moisture part-skim (LMPS) mozzarella is generally not available at our local retail shops, but instead, is sold to commercial distributors and processors for the pizza industry.

Pizza cheese

The United States is one of the leading producers of LMPS mozzarella. In fact, 33% of the total cheese production by American manufacturers in 2018 was accounted for by mozzarella cheese (~1.973.744 tonnes) (USDA, 2018). LMPS mozzarella makes up for the majority of the produced mozzarella; for example, more than 75% of the US produced mozzarella in 1985 was the LMPS variant. This mozzarella variant has extended shelf-life, excellent shredding properties and demonstrates good functional properties when baked on a pizza, in the form of stringy cheese with long stretch, while forming desirable melt appearances and limited oiling-off. LMPS mozzarella has, thus, gained worldwide interest because of its use in pizza, and has even been named ‘pizza cheese’ until 1964 (Kindstedt, 2004).

Functional shelf-life of frozen LMPS mozzarella

The increase in urban population size and disposable income are driving factors in the global pizza market. As economies continue to develop and home-deliveries become more available, an increase in demand and performance of mozzarella cheese is expected. The latter forms a challenge for some countries which suffer from local milk quality and supply issues, and therefore resort to importing LMPS mozzarella. Extended storage of the cheese could, however, result in poor shred and altered melting properties (Guinee, Mulholland, Mullins, Corcoran & Auty, 1999), which could result in non-compliant cheese and thus in an overall rejection by the customers. Our study demonstrated that LMPS mozzarella cheeses could be successfully frozen without loss of quality, i.e., similar textural, stretch and melt characteristics were attained, relative to unfrozen cheeses (To, 2020); hereby indicating that freezing was an efficient means for commercial producers to extend the functional shelf-life of LMPS mozzarella for long-distance export.

More information

• Guinee, T. P., Mulholland, E. O., Mullins, C., Corcoran, M. O., & Auty, M. (1999). The effects of processing and ripening on the quality of pizza cheese. Fermoy, County Cork, Ireland: End of project reports, Teagasc.

• Kindstedt, P., (2004). Pasta-filata cheeses. In: Fox, P.F. (2nd edn.), Cheese-Chemistry, Physics and Microbiology, (p. 337-362). Maryland, Aspen publishers.

• To, C.M., Vermeir, L., Rebry, F., Kerkaert, B., Van der Meeren, P., Guinee, T.P., (2020). Impact of freezing on the physicochemical and functional properties of low-moisture part-skim Mozzarella, International Dairy Journal, 106, 104704

• United States Department of Agriculture, (2018). Dairy Products 2018 - Summary, Agricultural Statistics Board, USDA, Washington, DC.