# Chemical-Sensory Traits of Fresh Cheese Made by Enzymatic Coagulation of Donkey Milk
## 3 Results and Discussion
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Item** & \multicolumn{2}{c}{**Donkey**} & \multicolumn{2}{c}{**Cow (Control)**} \\ \hline  & Milk & Cheese & Milk & Cheese \\ \hline pH & 7.01 \(\pm\) 0.03 a & 5.85 \(\pm\) 0.10 c & 6.71 \(\pm\) 0.02 b & 5.61 \(\pm\) 0.06 d \\ Total Solids\% & n.a. & 34.19 \(\pm\) 2.64 b & n.a. & 49.88 \(\pm\) 1.16 a \\ Protein\% & 2.21 \(\pm\) 0.11 d & 25.87 \(\pm\) 3.37 a & 3.33 \(\pm\) 0.07 c & 17.29 \(\pm\) 2.96 b \\ Fat\% & 0.33 \(\pm\) 0.08 d & 2.90 \(\pm\) 0.11 c & 3.62 \(\pm\) 0.39 b & 23.76 \(\pm\) 3.11 a \\ Lactose\% & 6.76 \(\pm\) 0.07 a & n.a. & 4.91 \(\pm\) 0.02 b & n.a. \\ Ash\% & 0.39 \(\pm\) 0.06 d & 3.31 \(\pm\) 0.30 b & 0.81 \(\pm\) 0.05 c & 4.83 \(\pm\) 0.44 a \\ Total processing time *, min & 42.10 \(\pm\) 6.82 a & & 13.20 \(\pm\) 0.20 b \\ Cheese yield\% & & 7.21 \(\pm\) 0.76 b & & 23.52 \(\pm\) 1.50 a \\ \hline \hline \end{tabular} Values in the same row bearing different superscripts (a,b,c,d) are significantly different, \(p\) < 0.05. n.a., not assessed;  
* from addition of rennet.  
\end{table} 
Table 1: Chemical characteristics of donkey and cow milk and corresponding cheeses (mean values \(\pm\) standard deviation (SD)). Figure 2: Donkey cheese manufacturing: curd at the cutting time (**a**); moulded curd (**b**); cheese after 24 h (**c**). The results agree with those obtained by [PERSON] and [PERSON] (2017) in samples taken at 90 days of lactation. Some differences were observed with the data of [PERSON] et al. (2018), who reported a different order of abundance. This discrepancy could be connected to a different lactation stage; however, the authors did not indicate the period in which they took the samples. The total amount of saturated fatty acids was very close to that found by [PERSON] et al. (2019) in milk from the Amiata donkey, whereas the concentration of polyunsaturated was much higher. The average TFA profile of the bovine milk used as control (bulk milk samples taken from an industrial dairy) was within the typical range of this type of milk, and the high saturated/polyunsaturated ratio suggests possible derivation from intensive farms. The TFA profile of the cheese showed some changes with respect to milk, due to an increase of some saturated compounds (in particular stearic acid) and decrease of the polyunsaturated ones (mainly linoleic and linoleic acids). This result was surprising, and was only partially reflected by the control, for which the differences were less pronounced and the significance was only found for stearic acid. At our knowledge, this argument has been poorly investigated, and more analyses are needed to confirm the result. A possible cause could lie in a different retention of the fat globules into the cheese, depending on their size. According to the literature, small sized and large sized globules of cow milk present some differences in the fatty acid composition of glycerides: the small globules contain less short chain fatty acids, less stearic and more oleic acid ([PERSON], 2017; [PERSON], 2018) than larger ones. For donkey milk, no information is available on TFA composition of fat globules glycerides, but [PERSON] et al. (2019) reported that globules have different size, ranging from less than 2 to more than 5 \(\upmu\)m, and that the small ones are much more abundant (about 70% of total). If, as theoretically expected, the small globules are less retained into the curd, some differences in the TFA profile of milk, cheese and whey should arise. Unfortunately, the TFA analyses of the whey samples did not give further elements for supporting this hypothesis, since the standard deviation was too high. A specific study is required to in order to clarify the matter.