Quality of olive oils and olive bagasse oil and their use in thermal processes

Olive oil is recognized due to its different properties, however, its most used form is in cold preparation, as there is still the belief that, once heated, olive oil would lose its beneficial properties to health and even form toxic substances. Thus, in order to assess the quality of olive oils and olive bagasse oil subjected to different temperatures and their use in thermal processes, the present study was developed at the Laboratory of Medicinal Plants, belonging to the State University's Department of Agronomy of Maringá. The following analyzes were performed when the oils reached temperatures of 10, 25 (room temperature), 140, 180, 220 and 260°C: acidity, peroxide index, iodine index and measurement of absorbance at 232 and 270 nm (ultraviolet). After the results obtained are compared with the standards of Codex Alimentarius, the Agência Nacional de Vigilância Sanitária, the Ministério da Agricultura, Pecuária e Abastecimento and the International Olive Council, it is concluded that even after heating, in most of the evaluated parameters, the oils remained in compliance with legislation, which can then be used in thermal processes.

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Proteinase and phospholipase activities and development at different temperatures of yeasts isolated from bovine milk

Journal of Dairy Research ◽

10.1017/s0022029911000434 ◽

2011 ◽

Vol 78 (4) ◽

pp. 385-390 ◽

Cited By ~ 6

Author(s):

Priscilla A Melville ◽

Nilson R Benites ◽

Monica Ruz-Peres ◽

Eugenio Yokoya

Keyword(s):

Dairy Products ◽

Room Temperature ◽

Bovine Milk ◽

Raw Milk ◽

Pathogenic Potential ◽

Proteinase Production ◽

Different Temperatures ◽

Quality Of Milk ◽

Means Of Transmission

The presence of yeasts in milk may cause physical and chemical changes limiting the durability and compromising the quality of the product. Moreover, milk and dairy products contaminated by yeasts may be a potential means of transmission of these microorganisms to man and animals causing several kinds of infections. This study aimed to determine whether different species of yeasts isolated from bovine raw milk had the ability to develop at 37°C and/or under refrigeration temperature. Proteinase and phospholipase activities resulting from these yeasts were also monitored at different temperatures. Five genera of yeasts (Aureobasidium sp., Candida spp., Geotrichum spp., Trichosporon spp. and Rhodotorula spp.) isolated from bovine raw milk samples were evaluated. All strains showed one or a combination of characteristics: growth at 37°C (99·09% of the strains), psychrotrophic behaviour (50·9%), proteinase production (16·81% of the strains at 37°C and 4·09% under refrigeration) and phospholipase production (36·36% of the isolates at 37°C and 10·9% under refrigeration), and all these factors may compromise the quality of the product. Proteinase production was similar for strains incubated at 37°C (16·81% of the isolates) and room temperature (17·27%) but there was less amount of phospholipase-producing strains at room temperature (15·45% of the isolates were positive) when compared with incubation at 37°C (36·36%). Enzymes production at 37°C by yeasts isolated from milk confirmed their pathogenic potential. The refrigeration temperature was found to be most efficient to inhibit enzymes production and consequently ensure better quality of milk. The viability of yeasts and the activity of their enzymes at different temperatures are worrying because this can compromise the quality of dairy products at all stages of production and/or storage, and represent a risk to the consumer.

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Formulations of Rancid and Winey-Vinegary Artificial Olfactory Reference Materials (AORMs) for Virgin Olive Oil Sensory Evaluation

Foods ◽

10.3390/foods9121870 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1870

Author(s):

Ramón Aparicio-Ruiz ◽

Sara Barbieri ◽

Tullia Gallina Toschi ◽

Diego L. García-González

Keyword(s):

Olive Oil ◽

Edible Oils ◽

Virgin Olive Oil ◽

Strict Sense ◽

Virgin Olive Oils ◽

Olive Oils ◽

International Regulations ◽

Sensory Defects ◽

And Control

Sensory assessment of virgin olive oil (“panel test”) is the only sensory method included in international regulations of edible oils and its application is compulsory. Even if its application has been a success in quality control, improving the quality of virgin olive oils over the last 30 years, at present, there is no reference material (RM), in the strict sense of the term, to be used as a validated standard for sensory defects of virgin olive oil with which tasters can be trained. Usually, real samples of virgin olive oils assessed by many panels for the International Olive Council (IOC) ring tests are used as materials of reference in panel training and control. The latter are highly representative of the main perceived defects, but availability is limited, samples are not homogeneous year after year, and other secondary defects can be present. Thus, in order to provide solutions, this work describes an analytical procedure for implementing olfactory formulations that emulate rancid and winey-vinegary defects found in virgin olive oils with the aim of providing reproducible RMs that can be prepared on demand. A strategy for designing RMs for aroma is presented and the optimization process to obtain the best formulation is described. Under the criteria of representativeness, verified with the advice of the IOC, aroma persistence, and simplicity in formulation, two RMs for winey-vinegary and rancid were obtained by diluting acetic acid and ethanol (winey-vinegary defect) and hexanal (rancid defect) together with other compounds that are used to modify aroma and avoid non-natural sensory notes.

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Tradition Mills’ Picholine Olive Oil Physicochemical Characterization and Chemical Profiling across Different Cities in Morocco

The Scientific World JOURNAL ◽

10.1155/2020/1804723 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Hamza El Moudden ◽

Yousra El Idrissi ◽

Chakir El Guezzane ◽

Walid Belmaghraoui ◽

Adil El Yadini ◽

...

Keyword(s):

Fatty Acids ◽

Olive Oil ◽

Unsaturated Fatty Acids ◽

Physicochemical Characterization ◽

Carotenoid Content ◽

Chemical Compositions ◽

Chlorophyll Contents ◽

Chemical Profiling ◽

Olive Oils

This study aims to determine the quality of olive oils (Picholine variety) from the traditional oil mills in different Moroccan cities by means of physicochemical characterization and chemical compositions. All samples of olive oil were collected from traditional oil mills. Physicochemical analyses of free fatty acid (FFA), iodine value (IV), saponification value (SV), specific extinction at 232 and 270 (E232, E270), chlorophyll content, carotenoid content, fatty acids (FAs), and total phytosterols composition were performed with respect to the International Olive Council (IOC) standards. These oils were revealed to be rich in unsaturated fatty acids (UFAs): C18 : 1, C18 : 2, and C18 : 3, and that the total phytosterols content ranged between 142.68 and 208.72 mg per 100 g of oil. Also, the chlorophyll contents, for most of the studied samples, are less than 2 mg/kg, while the carotenoid content varied between 0.13 and 0.63 mg/kg. These results, along with the physicochemical assays, helped classify the oils studied into three categories: extra virgin, virgin, and ordinary virgin olive oils. These results confirm that the conditions under which olive oils are collected, pressed, and stored influence the quality of the oil produced. Therefore, there is a need to inform producers about the correct practices and techniques for storage, processing, and conservation of oils to better improve the quality of the final product.

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Physico-chemical and sensory evaluation of virgin olive oils from several Algerian olive-growing regions

OCL ◽

10.1051/ocl/2021044 ◽

2021 ◽

Vol 28 ◽

pp. 55

Author(s):

Malika Douzane ◽

Mohamed-Seghir Daas ◽

Amel Meribai ◽

Ahmed-Hani Guezil ◽

Abdelkrim Abdi ◽

...

Keyword(s):

Olive Oil ◽

Virgin Olive Oil ◽

Principal Component ◽

Great Variability ◽

Olive Cultivar ◽

Virgin Olive Oils ◽

Olive Oils ◽

Physical Chemical ◽

Physico Chemical

Olive cultivar diversity is rich in Algeria but most remain unexplored in terms of quality traits. This work aimed to evaluate the physicochemical and organoleptic quality of twenty olive oil samples belonging to four Algerian cultivars (Chemlal, Sigoise, Ronde de Miliana and Rougette de Mitidja) collected throughout the national territory. Physical-chemical and sensory results showed that 60% of the oils belong to the extra virgin category, while 40% were classified as “virgin olive oil”. The results of the principal component analysis (PCA) revealed a great variability in fatty acids composition between the samples depending on the cultivar and origin. Oleic acid was the most abundant and varied between 64.84 and 80.14%. Extra virgin olive oils with quality attributes are eligible for a label. Rougette de Mitidja, Ronde de Miliana and Sigoise from Oran showed great potential.

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Standardization of the quality of olive oil

10.33920/igt-01-2108-07 ◽

2021 ◽

pp. 596-599

Author(s):

O.A. Rakhaev

Keyword(s):

Quality Assessment ◽

Olive Oil ◽

Vegetable Oils ◽

Member States ◽

Codex Alimentarius ◽

Interstate Standard

For the EAEU member states, olive oil is mainly an imported product, for which an acute problem is not only its identification, but also its quality assessment. The lack of an interstate standard for olive oil forces us to address to Codex Alimentarius standards and look for taxes in the regulations for other liquid vegetable oils.

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A Multi-Methodological Protocol to Characterize PDO Olive Oils

Metabolites ◽

10.3390/metabo8030043 ◽

2018 ◽

Vol 8 (3) ◽

pp. 43 ◽

Cited By ~ 6

Author(s):

Simone Circi ◽

Cinzia Ingallina ◽

Silvia Vista ◽

Donatella Capitani ◽

Andrea Di Vecchia ◽

...

Keyword(s):

Chemical Composition ◽

Olive Oil ◽

Geographical Area ◽

Principal Component ◽

Isotope Ratio Mass Spectrometry ◽

Isotopic Data ◽

Olive Oils ◽

Nmr Data ◽

Panel Test

An analytical approach including Panel Test, Isotope Ratio Mass Spectrometry (IRMS) and Nuclear Magnetic Resonance (NMR) spectroscopy was proposed to characterize Italian “Colline Pontine” PDO olive oils (40 samples) of two consecutive crop years. Our approach has evidenced the high quality of these olive oils. Only 6 of 40 olive oils samples were defined as “defective” by the official Panel Test due to the detection of negative sensory attributes. The low variability of isotopic data monitored by IRMS confirmed that the olive oil samples all came from a limited geographical area. NMR spectra did not evidence any chemical composition anomaly in the investigated samples. In order to assess the influence of harvesting year over the olive oil chemical composition, the NMR analysis was extended to other 22 olive oil samples of a third harvesting year. NMR data were submitted to two different statistical methods, namely, analysis of variance (ANOVA) and principal component analysis (PCA) allowing olive oils of three consecutive harvesting years to be grouped.

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

Scientific Reports ◽

10.1038/s41598-019-54088-z ◽

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.

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Use of Cold Water for Irrigation Reduces Stem Elongation of Plug-grown Tomato and Cabbage Seedlings

HortScience ◽

10.21273/hortsci.34.5.852 ◽

1999 ◽

Vol 34 (5) ◽

pp. 852-854 ◽

Cited By ~ 2

Author(s):

Junne-Jih Chen ◽

Yung-Wei Sun ◽

Tzay-Fa Sheen

Keyword(s):

Lycopersicon Esculentum ◽

Brassica Oleracea ◽

Room Temperature ◽

Cold Water ◽

Stem Elongation ◽

Dry Weight ◽

Stem Length ◽

Shoot Dry Weight ◽

Different Temperatures

Seedlings of tomato (Lycopersicon esculentum Mill.) and cabbage (Brassica oleracea L. var. Capitata) were planted in 240-cell plug trays in the greenhouse and subjected to irrigation with water at different temperatures once a day. Irrigation with cold (5 to 15 °C) water reduced stem length of tomato by 28% to 32% in comparison with irrigation with water at room temperature (27.5 to 30.5 °C). Use of water at 10 °C did not affect total shoot dry weight but increased the shoot dry weight per centimeter of stem. Irrigation with water at 5 °C reduced stem length of cabbage seedlings 40%, but use of water at 10 and 15 °C did not. Both shoot and root dry weights were increased by irrigation with water at 10 °C. These results demonstrate that irrigation with cold water provides an effective method for improving the quality of plug-grown seedlings.

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Characterization of ‘Castellana’ Virgin Olive Oils with Regard to Olive Ripening

HortTechnology ◽

10.21273/horttech03845-17 ◽

2018 ◽

Vol 28 (1) ◽

pp. 48-57 ◽

Cited By ~ 4

Author(s):

Carmen Mena ◽

Alejandra Z. González ◽

Raúl Olivero-David ◽

María Ángeles Pérez-Jiménez

Keyword(s):

Olive Oil ◽

Virgin Olive Oil ◽

Quality Parameters ◽

Virgin Olive Oils ◽

Olive Oils ◽

Wide Range ◽

Sensorial Quality ◽

Olive Ripening

The production of high-quality virgin olive oil from traditional olive (Olea europaea L.) varieties with peculiar and differential characteristics is of great interest for the olive oil market. ‘Castellana’ is an autochthonous variety mainly located in the center of Spain. The aims of this study were 1) the characterization of ‘Castellana’ virgin olive oils and 2) the evaluation of the influence of fruit ripening degree on the oil quality to establish an optimum harvest time for ‘Castellana’ olives. A wide range of physicochemical and sensorial quality parameters were assayed in oils produced at four harvest times during three crop seasons. ‘Castellana’ oils could be classified into the extra virgin category at all ripening degrees studied. This variety provides well-balanced oils from the sensorial point of view with an optimum chemical composition. Nevertheless, fruit maturation had a strong effect in various quality parameters, especially total phenol content, total tocopherol content, sensorial quality, and to a lesser extent in fatty acid composition. Loss of antioxidants and decrease in sensorial quality take place during olive ripening, reducing the nutritional, sensorial, and commercial quality of virgin olives oils as the harvest is delayed. Results suggest that the production of optimal extra virgin olive oil requires that ‘Castellana’ olives should be harvested from the middle of November to the middle of December, coinciding with a ripening index between 3.1 and 4.1. These results are of great importance to the olive oil industry for improving the quality of virgin olive oils produced from ‘Castellana’.

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Quality of Commercial Flavoured Oils and Seed Oils Using a Widespread Analytical Protocol

Journal of Food Research ◽

10.5539/jfr.v3n4p78 ◽

2014 ◽

Vol 3 (4) ◽

pp. 78

Author(s):

Luisa Mannina ◽

Stefania Cesa ◽

Riccarda Antiochia ◽

Silvia Vista ◽

Anatoly P. Sobolev ◽

...

Keyword(s):

Olive Oil ◽

Seed Oils ◽

Free Acidity ◽

Nutritional Properties ◽

Olive Oils ◽

Analytical Protocol ◽

Sunflower Oils ◽

A Minor ◽

C Nmr

Commercial flavoured olive and olive-sunflower oils and seed oils with particular nutritional properties (e.g. linseed, safflower, sunflower, sesame and rice oils) were analysed using a widespread analytical protocol to have information on their quality and chemical composition. The protocol involved traditional determinations (free acidity, peroxide value, UV and VIS spectrophotometric indices, and fatty acid composition) along with 1H and 13C NMR analyses. Most of flavoured olive oils turned out to be lampante olive oils and not extra virgin as declared in the label on the bottle. In the case of olive-sunflower oils only a minor fraction of olive oil was revealed although these products are particularly expensive and the presence of olive oil is emphasized on the label. In some seed oils, refinement processes, not indicated on the bottle, were highlighted. Some compounds characteristic of specific seed oils were identified in the 1H spectra.

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