scholarly journals Evaluation of changes in the quality of extracted oil from olive fruits stored under different temperatures and time intervals

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Samira Saffar Taluri ◽  
Seid Mahdi Jafari ◽  
Akbar Bahrami
Keyword(s):  
Olive Oil ◽  
Oil Quality ◽  
Acid Value ◽  
Poor Quality ◽  
Quality Parameters ◽  
Time Intervals ◽  
Different Temperatures ◽  
Negative Effect ◽  
Freezing Condition

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.

scholarly journals A Review on the Quality of Palm Oil (Elaeis guineensis) Produced Locally in Imo State, Nigeria

2018 ◽  
Vol 4 ◽  
pp. 40-50 ◽  
Author(s):  
Enyoh Christian Ebere ◽  
Verla Andrew Wirnkor ◽  
Enyoh Emmanuel Chinedu ◽  
Verla Evelyn Ngozi
Keyword(s):  
Palm Oil ◽  
Elaeis Guineensis ◽  
Meta Analysis ◽  
Oil Quality ◽  
Acid Value ◽  
Poor Quality ◽  
Smoke Point ◽  
Imo State ◽  
Open Access Journals

Over 70 % inhabitants of Imo state pend on palm oil for their cooking, frying etc. The study reviews available data on palm oil quality produced locally in Imo state with a view of providing up-to-date information and identify research gaps that could have health consequences on consumers. Peer reviewed scientific articles were reviewed and a meta-analysis of four different scientific research databases, PubMed, Web of Science, Google Scholar and Directory for Open-Access Journals was conducted. The result showed that palm oil produced locally in Imo state has average of pH (4.73), acid value (28.3 mg/KOH), FFA (14.15 mg/KOH), smoke point (115°C), iodine value (1.68 wijj’s), saponification value (197.07 mgKOH/g), ester value (168.77), moisture content (0.44 %), density (0.89 g/ml), SG (0.91), peroxide value (17.75 mEq./kg), refractive index (1.46oBx) and viscocity (60.04 cps). Overall palm oil is highly degraded and of poor quality since major quality indicators are not within Nigerian Industrial Standard and Standard Organization of Nigeria. Also, there is a dearth of information/data available on quality of palm oil produced locally in Imo state especially on its microbial status. Food scientist should look in that direction to enhance proper understanding of the quality of palm oil.

scholarly journals Quality and Safety of the Frying Oils used in Small or Medium-sized Food Enterprises in West Delhi, India

2021 ◽  
Vol 37 (3) ◽  
pp. 547-552
Author(s):  
Shalini Sehgal ◽  
Tanya L. Swer ◽  
Akshay Bhalla ◽  
N. Chandrakanth
Keyword(s):  
Fatty Acid Content ◽  
Oil Quality ◽  
Acid Value ◽  
Poor Quality ◽  
Quality And Safety ◽  
Chemical Parameters ◽  
Peroxide Values ◽  
Hydrogenated Fats ◽  
Cooking Practices

The present study investigates the cooking practices and oil used in small and medium sized street food vendors/ kiosks in the west zone of Delhi, India. A survey was conducted to collect information on vendor cooking practices and oil quality was analyzed using different physio-chemical parameters. The study revealed that the oil samples collected from the participating vendors displayed varied values of % FFA (free fatty acid) content (0.16±0.00 to 0.60±0.01), acid value (0.225±0.00 to 1.030±0.01), peroxide values (9.12±0.02 to 32.45±0.49) and iodine value (61.57±0.19 to 79.08±0.07) indicating poor quality of the oils used for the preparation of snacks. Study revealed that the majority of the vendors re-use oils and practice adulteration with hydrogenated fats which can significantly deteriorate the quality of oil and henceforth the health of the consumers.

scholarly journals Effect of crushing temperature on virgin olive oil quality and composition

2018 ◽  
Vol 69 (1) ◽  
pp. 239 ◽  
Author(s):  
Ö. Kula ◽  
A. Yıldırım ◽  
A. Yorulmaz ◽  
M. Duran ◽  
İ. Mutlu ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Olive Oil ◽  
Oil Quality ◽  
Virgin Olive Oil ◽  
Sterol Composition ◽  
Quality Parameters ◽  
Olive Oil Quality ◽  
Different Temperatures ◽  
Processing Techniques

The objective of the current study was to assess the influence of a modified crushing process and kneading operation on the quality parameters, volatile compounds, and the fatty acid and sterol profiles of virgin olive oil from the Edremit yaglik variety. In the study, olive oil samples were produced in two different processes. The first one was produced without malaxation and the second one was produced with the malaxing process. During crushing, the effect of different temperatures was tested. The results demonstrate that different crushing temperatures generally did not affect the amount of free fatty acids, or peroxide value. Total phenol contents were positively affected by the additional malaxation process. Fatty acids and sterol composition were not significantly altered at different crushing temperatures or during the subsequent malaxation application. PCA enabled a clear classification of the oils obtained from different processing techniques.

scholarly journals Reduction of Polycyclic Aromatic Hydrocarbons (PAHs) in Sesame Oil Using Cellulosic Aerogel

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 644
Author(s):  
Do-Yeong Kim ◽  
Boram Kim ◽  
Han-Seung Shin
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
High Performance ◽  
Oil Quality ◽  
Acid Value ◽  
Quality Parameters ◽  
Sesame Oil ◽  
Miscanthus Sinensis ◽  
Polycyclic Aromatic ◽  
And Control

The effect of cellulosic aerogel treatments used for adsorption of four polycyclic aromatic hydrocarbons (PAHs)—benzo[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene [BaP])—generated during the manufacture of sesame oil was evaluated. In this study, eulalia (Miscanthus sinensis var. purpurascens)-based cellulosic aerogel (adsorbent) was prepared and used high performance liquid chromatography with fluorescence detection for determination of PAHs in sesame oil. In addition, changes in the sesame oil quality parameters (acid value, peroxide value, color, and fatty acid composition) following cellulosic aerogel treatment were also evaluated. The four PAHs and their total levels decreased in sesame oil samples roasted under different conditions (p < 0.05) following treatment with cellulosic aerogel. In particular, highly carcinogenic BaP was not detected after treatment with cellulosic aerogel. Moreover, there were no noticeable quality changes in the quality parameters between treated and control samples. It was concluded that eulalia-based cellulosic aerogel proved suitable for the reduction of PAHs from sesame oil and can be used as an eco-friendly adsorbent.

Irrigation effects on phenolic profile and extra virgin olive oil quality of ''Chemlali'' variety grown in South Tunisia

2021 ◽  
Vol 141 ◽  
pp. 322-329
Author(s):  
Jihed Faghim ◽  
Mbarka Ben Mohamed ◽  
Mohamed Bagues ◽  
Kamel Nagaz ◽  
Tebra Triki ◽  
...  
Keyword(s):  
Olive Oil ◽  
Oil Quality ◽  
Virgin Olive Oil ◽  
Extra Virgin Olive Oil ◽  
Phenolic Profile ◽  
Olive Oil Quality ◽  
Irrigation Effects ◽  
South Tunisia

scholarly journals Identification and Quantification of Olive Oil Quality Parameters Using an Electronic Nose

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 674
Author(s):  
Nawaf Abu-Khalaf
Keyword(s):  
Olive Oil ◽  
Electronic Nose ◽  
Chemical Sensor ◽  
Chemical Constituents ◽  
Oil Quality ◽  
Quality Parameters ◽  
Signal Acquisition ◽  
Good Precision ◽  
Olive Oil Quality ◽  
Quality Categories

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.

scholarly journals Linseed oil: Characterization and study of its oxidative degradation

2020 ◽  
Vol 71 (1) ◽  
pp. 337 ◽  
Author(s):  
B. M. Berto ◽  
R. K.A. Garcia ◽  
G. D. Fernandes ◽  
D. Barrera-Arellano ◽  
G. G. Pereira
Keyword(s):  
Fatty Acid ◽  
Oxidative Stability ◽  
Induction Period ◽  
Room Temperature ◽  
Linseed Oil ◽  
Oxidative Degradation ◽  
Acid Value ◽  
Quality Parameters ◽  
Time Intervals ◽  
Accelerated Oxidation

This paper proposes to characterize and monitor the degradation of linseed oil under two oxidation conditions using some traditional oxidative and quality parameters. The experimental section of this study was divided into 2 stages. In the first one, three commercial linseed oil samples (OL1, OL2, and OL3) were characterized according to oxidative stability (90 °C) and fatty acid composition. In the second stage, the OL1 sample, selected due to its availability, was subjected to the following oxidation procedures: storage at room temperature conditions with exposure to light and air (temperature ranging from 7 to 35 °C) for 140 days and accelerated oxidation at 100 °C for 7h. Samples were collected at different time intervals and analyzed for oxidative stability (90 °C), peroxide value, and acid value. The results showed that all the samples presented a similar fatty acid profile and that the OL3 sample showed a higher induction period (p < 0.05). Regarding the oxidative degradation, the induction period of the OL1 sample reduced from 9.7 to 5.7 and 9.7 to 6.3 during 140 days of storage under room temperature and 7 h of accelerated oxidation, respectively. The end of induction period of the OL1 sample is expected to occur within 229 days according to an exponential mathematical model fitted to the induction period values at different temperatures. In addition, the OL1 sample met the limits proposed by Codex and Brazilian regulations for peroxide and acid values during the oxidation time intervals.

Effects of the Planting Density on Virgin Olive Oil Quality of “Chemlali” Olive Trees (Olea europaeaL.)

2010 ◽  
Vol 58 (23) ◽  
pp. 12469-12472 ◽  
Author(s):  
Mokhtar Guerfel ◽  
Chokri Zaghdoud ◽  
Khaled Jebahi ◽  
Dalenda Boujnah ◽  
Mokhtar Zarrouk
Keyword(s):  
Olive Oil ◽  
Oil Quality ◽  
Virgin Olive Oil ◽  
Planting Density ◽  
Olive Oil Quality ◽  
Olive Trees

scholarly journals Study on the Improvement of Essential Oil Quality and Its Repellent Activity of Betel Leaves Oil (Piper betle l.) from Indonesia

2018 ◽  
Vol 34 (6) ◽  
pp. 2913-2926 ◽  
Author(s):  
Dante Alighiri ◽  
Edy Cahyono ◽  
Willy Tirza Eden ◽  
Ersanghono Kusuma ◽  
Kasmadi Imam Supardi
Keyword(s):  
Citric Acid ◽  
Essential Oil ◽  
Sodium Carbonate ◽  
Iron Content ◽  
Oil Quality ◽  
Acid Value ◽  
Piper Betle ◽  
Significant Difference ◽  
Main Component

The study to improve the quality of Indonesia betel leaves oil is done by treatment of citric acid and sodium carbonate. The treatment showed that the iron content and acid value were reduced optimally in the addition of 5% (w/w) citric acid (12 hours, 50oC) and 5% (w/w) sodium carbonate (9 hours, 50oC) yielded 0.45 mg/L of iron content and 1.00 mg/g of acid value, respectively. The main component of Indonesia betel leaves oil are 4-allyl phenylacetate. The descriptive sensory analysis showed that there were differences between betel leaves oil from Bogor compared with Boyolali and Makassar. There is a significant difference that the content of betel leaves oil from Bogor contains an isoeugenol compound of 20.71% while, Boyolali and Makassar contain eugenol of 17.02 and 19.21%, respectively. The study of the insect repellency indicated that Indonesia betel leaves oil potentially used as mosquito of Aedes aegypti repellent.

Sign in / Sign up

Export Citation Format

Share Document