Influence of Calcium and Phosphorus, Lactose, and Salt-to-Moisture Ratio on Cheddar Cheese Quality: pH Changes During Ripening

Abstract

The pH of cheese is an important attribute that influences its quality. Substantial changes in cheese pH are often observed during ripening. A combined effect of calcium, phosphorus, residual lactose, and salt-to-moisture ratio (S/M) of the cheese on the changes in cheese pH during ripening was investigated. Eight cheeses with 2 levels of Ca and P (0.67 and 0.47% vs. 0.53 and 0.39%, respectively), lactose at pressing (2.4 vs. 0.78%), and S/M (6.4 vs. 4.8%) were manufactured. All the cheeses were salted at a pH of 5.4, pressed for 5 h, and then ripened at 6 to 8 degrees C. The pH of the salted curds before pressing and the cheeses during 48 wk of ripening was measured. Also, cheeses were analyzed for water-soluble Ca and P, organic P, and bound inorganic P during ripening. Changes in organic acids' concentration and shifts in the distribution of Ca and P between different forms were studied in relation to changes in pH. Cheeses with low S/M exhibited a larger increase in acid production during ripening compared with high S/M cheeses. Cheeses with the highest concentration of bound inorganic P exhibited the highest pH, whereas cheeses with the lowest concentration of bound inorganic P exhibited the lowest pH among the 8 treatments. Although conversion of lactose to short-chain, water-soluble organic acids decreased cheese pH, bound inorganic phosphate buffered the changes in cheese pH. Production of acid in excess of the buffering capacity (which was the case in low Ca and P and low S/M treatments) led to a low pH, whereas solubilization of bound inorganic P in excess to acid production (which was the case in high Ca and P and high S/M treatments) led to an increase in pH. However, for cheeses with high Ca and P and low S/M, changes in cheese pH were influenced by the level of residual lactose. Hence, pH changes in Cheddar cheese can be modulated by a concomitant control on the amount and state of Ca and P, level of residual lactose, and S/M of the cheese.

Effect of Wild Strains Used as Starter Cultures on Free Fatty Acid Profile of Urfa Cheese

“…On the other hand, the titratable acidity levels of the cheeses A, B and C fl uctuated after 90 days of ripening. This may be attributed to almost complete salt penetration to cheese after 30 days of ripening as increasing salt level in cheese results in decreasing total acidity in brined-type cheeses [Upreti & Metzger, 2007]. The combined effects of starter strains and ripening period on the development of acidity were signifi cant at p<0.05.…”

Viscoelastic behavior during the ripening of a commercial low-fat soft cheese

“…Buffering in cheese is related to the presence of proteins and inorganic constituents such as weak acids, bases and metal ion complexes [9]. The production of acid should lead to immediate solubilization of calcium and phosphate entrapped by the para-casein network, which would act as a buffer resisting the decrease in the pH [21].…”

“…Cheeses were transported in ice containers from the factory to the laboratory and were stored in a Tabai Comstar PR 4GM chamber (Tabai Espec Corp., Osaka, Japan) at 6°C. Cheeses were sampled at different ripening times (1,21,48 and 76 days) in triplicate. Four slices (3 cm thickness) parallel to the smallest surface (11.6 ± 0.3 cm × 7.4 ± 0.2 cm) were obtained from the central zone of the cheeses.…”

Effects of mineral content of bovine drinking water: Does iron content affect milk quality?

“…Milk used for cheese making must have the proper calcium to phosphorus ratio and pH to allow for a successful process (Upreti and Metzger, 2007). With a lower milk pH, the calcium is more soluble, altering colloidal casein needed for cheese making.…”