As Cheddar cheese ripens, the original structure is broken down by proteolysis and calcium (Ca) solubilization. High levels of intact casein are needed for structure building in process cheese. Our goal was to minimize structural changes during ripening using 4 strategies: (1) use of milk with higher casein, (2) minimizing the rennet amount used, (3) using camel chymosin as the rennet, as it is less proteolytic than calf chymosin, and (4) applying high-pressure processing (HPP) to the cheese shortly after manufacture. Cheddar cheese was made from ultrafiltered (UF) milk. The cheesemilk protein and casein contents of were ~5.15% and 4.30%, respectively. Three types of cheeses were made (n = 4) using different rennet levels: (a) control, which had 2.0 µL rennet/50 g milk, (b) 25% reduced, and (c) 50% reduced. During cheesemaking, a licensed cheesemaker maintained high draining pH. Cheeses had similar moisture contents (~37%). Four days after the cheese was made, half of the samples from each vat were kept as controls; the other half underwent HPP at 600 MPa for 3 min. Loss tangent (LT) values of cheese during heating were measured by small strain oscillatory rheology. Intact casein was measured using Kjeldahl method to measure total and pH 4.6 soluble N. Acid/base titrations were used to determine the buffering capacity and insoluble Ca as a percentage of total Ca. Cheeses were aged for 8 m and made into process cheese at 2-wk, 2, 4, 6, and 8-m time points to determine performance changes of the cheese over time. Split-plot design was used for statistical analysis of data. Max LT values in process cheese increased with aging of the natural cheese; HPP decreased the max LT. Casein breakdown was slowed by use of the camel chymosin; during 6 m of aging, proteolysis was not affected by rennet levels or HPP. Due to the high natural cheese pH caused by the high draining pH, insoluble Ca contents remained high during ripening. HPP only influenced the rheological properties. The use of camel chymosin, concentrated UF milk, and maintaining high draining pH seem to have greater effects on retaining structure-building character than the rennet amount or HPP treatment.