# Evaluation of a New Bulk Packaging Container for the Ripening of Feta Cheese
## 3 Results and Discussion
### Textural Parameters of Feta Cheeses  
The textural parameter values are shown in Figure 3. Cheese hardness (Figure 3a) was affected (\(p<0.05\)) by both the packaging material and the ripening time. Cheeses packaged in wooden barrels and stainless-steel tanks (day 60) showed higher (\(p<0.05\)hardness values compared to those packaged in tin can containers. This may be related to the higher loss of moisture in cheeses packaged in wooden barrels and stainless-steel tanks compared to those in the tin cans. Regarding the effect of time, as ripening proceeded, hardness increased (\(p<0.05\)) from 13.51 N (day 1) to 32.08 N (day 100). According to [PERSON] [35], the texture of cheese undergoes continuous changes during ripening as a consequence of biochemical reactions, i.e., (i) proteolysis, (ii) the decrease in water activity due to the release of water-binding ionic groups, (iii) the redistribution of salt, and (iv) the evaporation of water, as well as changes in pH. On the one hand, during cheese ripening, caseins are hydrolyzed into large and intermediate-sized peptides, which are further transformed into smaller peptides or amino acids by enzymes released from starter and non-starter bacteria. The enzymatic degradation of proteins is thought to reduce cheese hardness [9]. On the other hand, another feature of proteolysis is likely also significant. As each peptide bond is cleaved during proteolysis, two new ionic groups are generated, and each of these competes for the available water in the system. Thus, the water that was previously available for the solvation of the protein chains becomes tied up with the new ionic groups. As a result, the cheese becomes increasingly hard with age and more resistant to deformation. The diffusion of NaCl into the cheese mass also tends to bind the available water, enhancing the above effect [36]. In addition to the above factors, the firmness of cheese tends to increase during ripening, as the loss of moisture from the cheese mass results in an increase in the casein-to-moisture ratio. This often overrides the normal decrease in firmness due to the hydrolysis of the casein matrix [37].  
Cheese fracturability/brittleness (Figure 3b) was also affected (\(p<0.05\)) by the packaging material and ripening time. Cheeses packaged in wooden barrels showed higher (\(p<0.05\)) fracturability on day 40 and beyond compared to those in stainless-steel tanks and tin can containers. This may be attributed to the fact that the latter samples were ripened in the presence of brine, whereby this moisture acted as a plasticizer, resulting in reduced fracturability. Regarding the effect of time, as ripening proceeded, fracturability increased (\(p<0.05\)) due to the evolution of protein breakdown, resulting in a weaker casein network. Fracturability ranged from 11.42 N (day 1) to 21.27 N (day 100).  
The present results on texture are in general agreement with those of [PERSON] and [PERSON] [36] for white-brined cow cheeses; [PERSON] et al. [38] for soft camel cheeses; [PERSON] et al. [9] for full-fat and low-fat white-brined goat cheeses; and [PERSON] and [PERSON] [39], who reported the increasing hardness and stress at fracture of for haloumi cheese with ripening time. In contrast to the above findings, [PERSON] et al. [19] and [PERSON] and [PERSON] [40] reported a relatively softer texture for white-brined cow cheeses at the end of ripening, as a result of the hydrolysis of caseins.  
Figure 3: Main effects plots for the textural parameters of the (**a**) hardness and (**b**) fracturability of Feta cheese as a function of the packaging material and ripening time.