Effect of different foliar particle films (kaolin and zeolitite) on chemical and sensory properties of olive oil

Author(s):  
Annalisa Rotondi ◽  
Gianpaolo Bertazza ◽  
Barbara Faccini ◽  
Giacomo Ferretti ◽  
Lucia Morrone

<p>During the growing season, the use of foliar treatments based on fine grained geomaterial to reduce the negative impact of environmental stresses and protect the olives from insect pests is a well-known approach; however, while kaolin powders have been widely employed, zeolitite-based materials are much less known and exploited.</p><p>The aim of this study is to assess the effect of the two different treatments (zeolitite and kaolin) on the chemical and sensory qualities of the oils produced.</p><p>The study was carried out during two consecutive crop seasons in a 15 year old commercial olive orchard (Olea europaea), cv Correggiolo, located on the Appennine hills near Bologna (Italy). Foliar treatments were distributed during summer, until olive harvest. Ripening index, weight, oil and water content were measured on olive fruits. Olive productions were transformed in oils using a low scale continuous mill, quality parameters (free acidity, peroxide numbers, K232, K270, total phenols, fatty acids) were evaluated according to the official methods described in Regulation EC 2568/91 and subsequent amendments. Phenolic compounds, vitamins and pigments were determined by HPLC-DAD. Sensory analysis was performed by the panel of Agency for Agrofood Sector Services of Marche region (ASSAM), a fully-trained analytical taste panel recognized by the International Olive Oil Council (IOC) of Madrid, Spain, and by the Italian Ministry for Agriculture, Food, and Forestry Policy.</p><p>Olives treated with zeolite showed higher oil contents with respect to the other treatments. Oils produced by plants treated with zeolite particle film exhibited higher contents of total phenols, tyrosol, oleuropein and secoiridoids than to the oils produced by other treatments. Oils produced from olives treated with kaolin had sensory profiles characterized by sweet notes ascribable to ripe fruits, the tasters perceived notes of berries that are not typical of the Correggiolo cultivar.</p><p>The sensory taint test revealed a statistically significant difference between oils produced from olives treated with kaolin and the control, whereas no difference emerged between oils obtained from olives treated with zeolite and the control.</p><p>Particle film can influence some physiological plant parameters (photosynthesis, transpiration, water use efficiency) and, by consequence, it has also an influence on olive and oil quality. Olive plants treated with zeolite produced oils with higher antioxidant endowment, while oils produced from plants treated with kaolin were characterized by lower phenolic contents. Moreover, the kaolin treatment significantly affected the organoleptic properties of oils.</p>

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 674
Author(s):  
Nawaf Abu-Khalaf

An electronic nose (EN), which is a kind of chemical sensor, was employed to check olive oil quality parameters. Fifty samples of olive oil, covering the four quality categories extra virgin, virgin, ordinary virgin and lampante, were gathered from different Palestinian cities. The samples were analysed chemically using routine tests and signals for each chemical were obtained using EN. Each signal acquisition represents the concentration of certain chemical constituents. Partial least squares (PLS) models were used to analyse both chemical and EN data. The results demonstrate that the EN was capable of modelling the acidity parameter with a good performance. The correlation coefficients of the PLS-1 model for acidity were 0.87 and 0.88 for calibration and validation sets, respectively. Furthermore, the values of the standard error of performance to standard deviation (RPD) for acidity were 2.61 and 2.68 for the calibration and the validation sets, respectively. It was found that two principal components (PCs) in the PLS-1 scores plot model explained 86% and 5% of EN and acidity variance, respectively. PLS-1 scores plot showed a high performance in classifying olive oil samples according to quality categories. The results demonstrated that EN can predict/model acidity with good precision. Additionally, EN was able to discriminate between diverse olive oil quality categories.


Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2257
Author(s):  
Rajan Bhatt ◽  
Jagdish Singh ◽  
Alison M. Laing ◽  
Ram Swaroop Meena ◽  
Walaa F. Alsanie ◽  
...  

Groundwater and soil potassium deficiencies are present in northern India. Sugarcane is a vital crop in the Indian Punjab; it is grown on approximately 91,000 hectares with an average yield of 80 tonnes ha−1 and a sugar recovery rate of 9.59%. The role of potassium (K) fertilizer under both sufficient and deficient irrigation in ratoon sugarcane crops is not well documented. We conducted a split-plot ratoon cane experiment during 2020–2021 at the Gurdaspur Regional Research Station of Punjab Agricultural University, India, on K-deficient soils. Main treatments were fully irrigated (I1) and water stressed (I0) conditions, with sub-treatments reflecting K fertilizer application rates of 0 (M1), 67 (M2), 133 (M3), and 200 (M4) kg K ha−1. The ratoon sugarcane performance was assessed in terms of growth, productivity, sugar quality and incidence of key insect pests. At harvest, trends in the growth and yield parameters in I1 were improved over the I0 treatment, with cane height (+12.2%), diameter (+3.3%), number of internodes (+5.4%), biomass yield (+7.6%) and cane yield (+5.9%) all higher, although little significant difference was observed between treatments. Ratoon cane yield under irrigation was 57.1 tonnes ha−1; in water-stressed conditions, it was 54.7 tonnes ha−1. In terms of sugarcane quality parameters, measured 12 months after harvesting the initial seed crop, values of Brix (+3.6%), pol (+3.9%), commercial cane sugar percentage (+4.0%) and extractable sugar percentage (+2.8%) were all higher in the irrigated treatments than the water-stressed plot. Irrigated treatments also had a significantly lower incidence of two key insect pests: top borer (Scirpophaga excerptalis) was reduced by 18.5% and stalk borer (Chilo auricilius) by 21.7%. The M3 and M4 treatments resulted in the highest cane yield and lowest incidence of insect pests compared to other K-fertilizer treatments. Economic return on K-fertilizer application increased with increasing fertilizer dosage. Under the potassium-deficient water-stressed conditions of the region of north India, a fertilizer application rate of 133 kg K ha−1 is recommended to improve ratoon sugarcane growth, yield, and quality parameters and economic returns for sugarcane farmers.


2021 ◽  
Vol 10 (1) ◽  
pp. 39
Author(s):  
Omar H. Dib ◽  
Christophe B. Y. Cordella ◽  
Rita Yaacoub ◽  
Hussein Dib ◽  
Nathalie Locquet ◽  
...  

The impact of harvest period on the quality parameters, polyphenols, fatty acids, sterols, and volatile compounds of Lebanese olive oil from the Soury variety was investigated in this study. Two groups of olive oil were compared, each with a specific harvest date. HD1 was harvested in October, whereas HD2 was picked in November. The analysis of both olive oil categories showed that HD2 witnessed a significant increase in all quality parameters except K270 and a decrease in total polyphenol content from 138 mg/mL to 44 mg/mL. Oleic and linoleic acids had an inverse relation, where the former decreased and the latter increased with the harvest date’s advancement. Palmitic acid in both groups was higher than the standards set for extra virgin olive oil. The relative amount of β -Sitosterol was mainly found to decrease, while those of stigmasterol, ∆5,24 -stigmastadienol, ∆7 -stigmastenol, and ∆7 -avenasterol increased with delaying harvest time. As for the volatile compounds, principle component analysis was used on the flash GC data to differentiate HD1 from HD2. Ethanol was found mostly characterizing HD2, whereas HD1 was influenced by 1-hexanol and (E,E)-2,4-decadienal. It can be concluded that the Soury variety should be harvested early, and a delay would result in the declassification of Lebanese olive oil quality from extra virgin to virgin olive oil.


2019 ◽  
Vol 11 (9) ◽  
pp. 2611 ◽  
Author(s):  
Andrea Casson ◽  
Roberto Beghi ◽  
Valentina Giovenzana ◽  
Ilaria Fiorindo ◽  
Alessio Tugnolo ◽  
...  

The olive oil industry is a significant productive sector in the European Union and the related production process is characterised by practices and techniques associated with several adverse effects on the environment. In the literature, many works on the environmental impact assessment of the olive oil chain have been carried out but the effects of the analytical analyses procedures were considered to be negligible. Currently, the reduction of solvents and of energy consumption in the laboratory has become a crucial aspect to be investigated. In this scenario, non-destructive optical methods based on visible/near-infrared (vis/NIR) spectroscopy represent a simple, rapid, and easy-to-use method to predict olive and olive oil quality parameters. Therefore, the aim of the work was to evaluate the environmental impact of the use of optical vis/NIR technologies for analytical assessment in comparison to chemical analyses on olive oil. The life cycle assessment method (LCA) was used. The functional unit defined for this study was the analysis and a “from cradle to grave” approach was applied. The vis/NIR technology results were distinctly better, by 36 times on average, than the chemical methods. Attention must be paid to the calibration phase of the vis/NIR instrumentation: In this case, the two methods must coexist for this initial procedure to obtain the required reference data for a reliable chemometric model. In conclusion, the vis/NIR spectroscopy gives very reliable results and can be considered a green technology, representing a choice among applications of low environmental impact analytical technologies.


2019 ◽  
Vol 8 (2) ◽  
pp. 67-75
Author(s):  
A. Iddir ◽  
A M. A. Bekada ◽  
S. Kiciri ◽  
S. Boualit

The aim of this work was to determine the composi on, physicochemical and quality parameters of Chemlal EVOO from di erent regions of Algeria and at di erent harvest me. Olive-oil yield, quality indices, fa y acid composition, pigments (carotenoids and chlorophylls), phenolic compounds were evaluated for a complete descrip on of olive-oil samples. The nal results showed that the altitude and the me of harvest obviously had an in uence on the quality and the chemical composition of the olive oils. A very advanced maturity was observed for the olives coming from the low altitudes. The olives of the region of Oran at 80 m of al tude ripen very quickly that the olives of M'chedallah to 474 m and more than those of the region of Illit- en which is more than 700 m. The pro le of fa y acids was in uenced by al tude. Oleic acid, which is a nutri onal and quality criterion for olive oil, increases with al tude but does not exceed the limit set by the Interna onal Olive Council. On the other hand, the content of pigments and phenolic compounds, decreased with the matura on of olives. According to the results found, the most suitable ripening index for harves ng olives for Chemlal EVOOs of high chemical quality starts from 3.20 up to 4.


2015 ◽  
Vol 47 (3) ◽  
pp. 109 ◽  
Author(s):  
A. Harbi ◽  
K. Abbes ◽  
Bouthaina Dridi-Almohandes ◽  
B. Chermiti

Insect-proof screens constitute efficient physical means of protecting horticultural crops against insect pests and their use has become widespread. However, they may have a negative impact on plant growth and fruit quality by modifying climatic parameters of greenhouses. In case of tomato crops, they are used mainly against white flies and the tomato leaf miner <em>Tuta absoluta</em> (Meyrick). In Tunisia, tomato plastic tunnels are often netted following two modalities: i) complete netting of the greenhouse under the plastic screen (total netting); or ii) netting only doors and lateral aeration windows (partial netting). Weekly monitoring of <em>T. absoluta</em> in two tomato greenhouses with different netting setups using pheromone traps and sampling of leaves and fruits showed no differences in the levels of infestation by the pest with a maximum average values of 6.66 eggs/leaf, 4.16 larvae/leaf and 4.16 mines/leaf. The maximum infestation rate of leaves was 86.66% and that of fruits was 10.83%. No effects of the netting setup used on plant growth parameters were detected. However, the study of fruit quality parameters revealed significant decrease in sugar contents in tomato fruits when using total netting setup (4.26°Brix <em>versus</em> 3.68°Brix). Recommendations regarding the combined use of pheromones traps and insect-proof nets are given and possibilities to enhance the efficiency of nets as physical barrier against <em>T. absoluta</em> are explored.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Samira Saffar Taluri ◽  
Seid Mahdi Jafari ◽  
Akbar Bahrami

AbstractChilling and freezing injuries of olives harvested in geographically high elevated locations may affect the quality of olive, and subsequently lead to oil with a poor quality. This study was aiming to investigate the influence of whether changes and freezing condition on the quality of extracted olive oil. The olive Koroneiki cultivar obtained from two origins was stored at three different temperatures (20, 5 and −18 °C) before oil extraction and common analyses (oil yield, acidity, peroxide value, thiobarbitorik acid value, total phenolics level, and color) were carried out in different time intervals (0, 20, 40, and 60 days) in order to assess the olive oil quality. Our data revealed that longer storage times significantly (P < 0.05) decreased the quality of olive oil. The fruits remained at 20 °C provided the lowest oil quality in all parameters. For example, the acidity of olive oil at 20 °C was 177% higher than samples kept at 5 °C after 20 days of olive storage. The general trend for comparing the quality parameters of extracted oils from olives kept at different temperatures was −18 > 5 > 20 °C. No significant negative effect (P < 0.05) was found for the samples kept at −18 °C, compared to 5 °C. Also, the geographical source of olive had a statistically significant influence (P < 0.05) on the quality of olive oil.


2019 ◽  
Vol 10 (1) ◽  
pp. 114 ◽  
Author(s):  
Antonia Tamborrino ◽  
Stefania Urbani ◽  
Maurizio Servili ◽  
Roberto Romaniello ◽  
Claudio Perone ◽  
...  

The aim of this study was to evaluate the ability of pulsed electric field (PEF) technology to improve the extractability and enhance the oil quality in an industrial olive oil extraction process. Using a PEF device on olive pastes significantly increased the extractability from 79.5% for the control, up to 85.5%. The PEF system did not modify the primary legal quality parameters or total concentrations of phenols, aldehydes, and esters. On the contrary, the non-thermal treatment slightly enhanced the dialdehydic forms of decarboxymethyl elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA) and tyrosol (p-HPEA-EDA), and decreased the total saturated and unsaturated C5 and C6 alcohols of the PEF EVOO (Extra Virgin Olive Oil) compared to the control test. This study confirmed that PEF technology can improve olive oil extraction and quality.


2018 ◽  
Vol 7 (6) ◽  
pp. 79 ◽  
Author(s):  
Ana Claudia Ellis ◽  
Adriana Gambaro

Since the year 2002, the Uruguayan oil-producing sector has been growing at a steady peace, utilizing over 10,000 seeded hectares across the country. The aim of this study was to characterise both the chemical and sensory properties of the extra virgin olive oil variety known as Arbequina through two consecutive harvests. The work was carried out using olives with three different ripening indices; the oil was extracted using an Abencor system. The moisture of the olive, yield extraction, and yield on both a dry and wet basis were determined. The obtained oils were characterized by determining the free acidity, main antioxidant compounds (polyphenols and tocopherols), composition of fatty acids, and sensory profiles. Olive moisture was over 57%, which led to production of pomaces characterized as &ldquo;difficult pastes&rdquo;, explaining the low yield obtained. The harvest year and ripening index affected different parameters such as Abencor yield and, on a dry basis, the free acidity, polyphenolic content, oleic acid, and linoleic acid contents and fruity, bitter, and pungent intensities. To determine the best time of harvest, it is important to consider the balance between yield (which is significantly greater in olives with a ripening index above 3) and oil quality, as a higher ripening index decreases positive sensory attributes such as pungency and bitterness intensities.


Sign in / Sign up

Export Citation Format

Share Document