# Nutritional Values of Onion Bulbs with Some Essential Structural Parameters for Packaging Process
## 3 Results and Discussion
### Physical and Structural Parameters  
Table 1 shows the physical and structural parameters of five onion bulbs. The average moisture content (\(M_{c}\)) of the fresh onion bulbs was high for all varieties (88.65%). The Yellow variety hadthe highest value (92.59%). [PERSON] et al. [22] reported similar moisture contents for onion varieties cultivated in Cameroon. As a result, rotting and sprouting are influenced by high moisture content [10; 11]. Green onion produced the longest length of 106.98 cm; the Yellow bulb hadthe largest thickness and width. From [PERSON] al. [32], who studied Iranian onions, the values of length, width, and thickness were in agreement with the onion variety bulbs. Green onion gave the highest mean weight (236.67 g), followed by Yellow, Red, Baby, and Leek, which had mean weights of 227.63 g, 155.41 g, 19.70 g, and 11.70 g, respectively. \(S_{p}\) of the onion bulbs wasreported to be 1.01, 0.90, 0.02, 0.01, and 0.88 for Yellow, Red, Green, Leek, and Baby onion, respectively.  
The highest and the lowest diameters were observed for Yellow and Leek, respectively. Against [PERSON] et al. [32], geometric mean diameter results were recorded (69.23-73.14 mm). The highest and the lowest values of actual volume were for Green and Leek varieties, respectively. The results were in agreement with [PERSON] al. [33]. The ellipsoid and prolate spheroid volumes were (245.23, 250.26 cm\({}^{3}\)), (201.42, 202.78 cm\({}^{3}\)), (304.27, 302.04 cm\({}^{3}\)), (20.53, 20.28 cm\({}^{3}\)), and (22.45, 31.54 cm\({}^{3}\)) for onion varieties Yellow, Red, Green, Leek, and Baby, respectively. The mean surface area was 187.08, 163.56, 53.74, 165.33, and 38.70 cm\({}^{2}\), respectively. Sphericity of onion varieties was 0.99, 0.93, 0.08, 0.05, and 0.82 for Yellow, Red, Green, Leek, and Baby onions, respectively. These results, in comparison with the studyof [PERSON] et al. [32], showed that Azarshahr and Sefide Qom onion varieties were similar to our studied varieties. The packaging coefficient showedthe highest value for Leek (0.68) and the lowest value for Red (0.35).  
The relationships between the main dimensions and mass are as follows:  
\begin{tabular}{l l} For Yellow bulb: & \(L=1.00X\)\(W=1.02\)X \(T=0.35\)X \(M\) \\ For Red bulb: & \(L=1.12X\)\(W=1.13X\)\(T=0.54\)X \(M\) \\ For Green onion: & \(L=46.31X\)\(W=45.90X\)\(T=4.58X\)\(M\) \\ For Leek onion: & \(L=80.32X\)\(W=78.12X\)\(T=63.67X\)\(M\) \\ For Baby bulb: & \(L=1.14X\)\(W=1.59X\)\(T=2.16X\)\(M\) \\ \end{tabular}  
Figure 3: Amino acid profile.  
The highest true and bulk densities were 1299.59 and 400.22 kg/m\({}^{3}\) for the Baby onion variety, respectively, shown in Table 2. The corresponding values for Yellow were 926.44, 365.61 kg/m\({}^{3}\), Red 986.24, 323.78 kg/m\({}^{3}\), Green 1062.11, 224.47 kg/m\({}^{3}\), and Leek 579.79, 188.18 kg/m\({}^{3}\). A true density of 1025-1063 kg/m\({}^{3}\) was found in a previous study [10]. Bulk density results in [PERSON] et al. [32] showed an agreement with our study. Density information is needed in the separation processes of onion bulbs [17]. The highest value of the density ratio was for the Baby onion variety and the lowest was for the Green onion variety. The porosity of Green onionhadthe highest value of 76.66%; on the other hand, Baby onion recorded the lowest value of 55.08%.