Effect of geographical location and soil fertility on main phenolic compounds and fatty acids compositions of virgin olive oil from Leccino cultivar in China

Enhancing mechanical and blocking properties of gelatin films using zein-quercetin nanoparticle and applications for strawberry preservation

New gelatin films incorporated with zein-quercetin nanoparticles (GA/ZQNPs) were developed. The GA/ZQNP films had improved tensile strength, water vapor and oxygen barrier capabilities, hydrophobicity, UV blocking feature, antioxidant activities and antimicrobial properties, which varied with various contents of ZQNPs. Notably, the GA/ZQNP0.1-10 films exhibited enhanced tensile stress value around 3.2 MPa and strain of 142 %, a 78.4 % decrease in water vapor permeability, a 76.9 % decrease in oxygen permeability, the highest water contact angle at 112.0 ± 0.6°, an improved DPPH∙ scavenging rate of 64.9 ± 0.7 %, excellent UV blocking properties and antimicrobial properties. The GA/ZQNP films were further applied for strawberries packaging to assess their preservation capabilities under ambient conditions. The results showed that GA/ZQNP0.1-10 nanocomposite films efficiently maintained the best nutrient quality and acceptable appearance of strawberries compared with untreated strawberries, prolonging the shelflife of strawberries to approximately 8 days. These findings suggested promising applications for these new functional films in fruit packaging.

Looking for Typical Traits in Monovarietal VOOs According to Their Phenolic Composition

Due to its high sensitivity to numerous variability sources, it is hard to define the typicity of a monovarietal virgin olive oil (VOO) according to its phenolic profile. In this study, we aimed to identify the features of phenolic composition that are persistent and minimally affected by variability sources, making them potential varietal markers. We separately analyzed three databases of monovarietal VOO phenolic compositions, determined by liquid chromatography, from three different cultivars. The first database was produced from the original data of the Bosana cultivar. The other two were obtained through a systematic analysis of scientific literature on Coratina and Frantoio cultivars. Several statistical tools, including coefficient of variability, correlations, and linear regression models, were used to find recurring proportions or ratios unaffected by variability sources suitable to define typical varietal traits. Some proportions between molecules, mostly within the same phenolic class, remain constant. Strong correlations between (i) flavonoids were observed in Bosana and Frantoio VOOs (R2 = 0.87 and 0.77, respectively), (ii) oleacein-oleocanthal (Bosana, R2 = 0.81) (iii) oleuropein aglycon-ligstroside aglycon (Frantoio, R2 = 0.88), and (iv) lignans (Coratina, R2 = 0.84). These traits could be useful tools for defining the typicity of monovarietal VOOs.

Effect of Geographical Location on the Phenolic and Mineral Composition of Chetoui Olive Leaves

In this study, we investigated the influence of pedological parameters and variation of altitude on the mineral nutrients, phenolic compounds, and antioxidant activities of olive leaves. Samples of the Chetoui cultivar were collected from eight geographical locations with different altitudes. Levels of phenolic compounds varied according to the altitude. Classification of the locations revealed that altitude 1 (>500 m) was characterized by high levels of secoiridoids and simple phenols, while altitude 2 (500-300 m) and altitude 3 (<300 m) were higher in flavonoids. Levels of Mn, Ca and B in the leaves and level of Zn in the soil were significantly correlated with the abundance of oleuropein and luteolin-7-O glucoside, the most important phenols in Chetoui olive leaves. The results suggest that, in addition to pedological criteria, environmental conditions also influence the formation of phenolic compounds.

The Introduction of Allochthonous Olive Variety and Super High-Density System in the Abruzzo Region: A Study on Olive Oil Quality

The transition to a sustainable economic and environmental management of olive oil sector needs to be implemented in both national and regional territories through the introduction and development of innovative growing systems and variety. In this study, the olive oil quality parameters of local and allochthonous varieties cultivated in different orchards located in the Abruzzo region (Italy), using traditional and super high-density systems, were analyzed. Frantene, Lecciana, Koroneiki, and a mix of Arbequina and Lecciana provided olive oils rich in flavonoids and secoiridoids compounds with respect to the local varieties Frantoio, Leccino, and a mix of Dritta, Leccino, and Pendolino. Oleic/linoleic ratio was influenced by cultivar and training systems with super high-density olive oils rich in oleic acid. Frantene showed a peculiar fatty acid profile different from cultivars grown in the same location; moreover, interesting similarities were found between Frantene and the mix of Dritta, Leccino, and Pendolino in terms of health-related compounds. The potential development of innovative sustainable training system to improve olive oil quality was highlighted. The study's results identify olive varieties suitable for super high-density systems spread in the Abruzzo region, representing a valid alternative for the olive growers to improve both the quality of the olive oil, as well as the company's income.

Effect of Variety and Maturity Index on the Physicochemical Parameters Related to Virgin Olive Oil from Wudu (China)

Physical parameters (i.e., extraction yield, oil content), chemicals (i.e., fatty acids, phenolics) and oxidative stability associated with virgin olive oil (VOO) from ten varieties in Wudu, China, were analyzed as a function of maturity index and variety by multivariate analysis models. Most of the analytical parameters were significantly affected by the variety and maturity index, and the former was more influential than the latter. Phenolics were the principal factor dividing the ten varieties into four groups. High phenolic levels were observed in the 'Koroneiki' group and 'Manzanilla' group, but the oil extractability index differentiated between them, being the highest and lowest, respectively. The 'Koroneiki' group demonstrated high oil productivity and oil quality, which was worthy of promotion in large-scale cultivation. High amounts of linoleic enhanced the VOO health benefits of 'Ascolana tenera, Arbequina and Zhongshan24' group, but brought the risk of shortening the shelf-life. The 'Ulliri Bardhe, Empeltre, Ezhi8, Yuntai14 and Picual' group clustered for the higher relative value of oleic acid. The maturity index had significant negative effects on the content of total phenolics, oleacein, oleocanthal, and oleic acid, but had a positive effect on the extractability index, which suggested that varieties with low phenolics and oleic acid levels should be harvested early.