scholarly journals Effect of Deep Frying of Potatoes and Tofu on Thermo-Oxidative Changes of Cold Pressed Rapeseed Oil, Cold Pressed High Oleic Rapeseed Oil and Palm Olein

Antioxidants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1637
Author(s):  
Małgorzata Wroniak ◽  
Marianna Raczyk ◽  
Bartosz Kruszewski ◽  
Edyta Symoniuk ◽  
Dominika Dach
Keyword(s):  
Rapeseed Oil ◽  
Palm Olein ◽  
Stability Index ◽  
Acid Value ◽  
Protein Product ◽  
Smoke Point ◽  
Deep Frying ◽  
Chlorophyll Pigments ◽  
High Oleic ◽  
Cold Pressed

One of the commonly used food preparation methods is frying. Fried food is admired by consumers due to its unique taste and texture. Deep frying is a process of dipping food in oil at high temperature, usually 170–190 °C, and it requires a relatively short time. The aim of this study was to analyze the thermo-oxidative changes occurring during the deep frying of products such as potatoes and tofu in cold pressed rapeseed oils and palm olein. Cold pressed rapeseed oil from hulled seeds (RO), cold pressed high oleic rapeseed oil from hulled seeds (HORO), and palm olein (PO) (for purposes of comparison) were used. Characterization of fresh oils (after purchase) and oils after 6, 12, and 18 h of deep frying process of a starch product (potatoes) and a protein product (tofu) was performed. The quality of oils was analyzed by determining peroxide value, acid value, p-anisidine value, content of carotenoid and chlorophyll pigments, polar compounds, smoke point, color (CIE L*a*b*), fatty acids content and profile, calculation of lipid nutritional quality indicators, and oxidative stability index (Rancimat). Cold pressed high oleic rapeseed oil was more stable during deep frying compared to cold pressed rapeseed oil, but much less stable than palm olein. In addition, more thermo-oxidative changes occurred in the tested oils when deep frying the starch product (potatoes) compared to the deep frying of the protein product (tofu).

PERFORMANCE OF “PACKAGED” AND STANDARD PALM OLEIN OIL IN FRYING KERUPUK JALIN

2012 ◽  
Vol 2 (1) ◽  
pp. 34-40
Author(s):  
Budiyanto Budiyanto ◽  
Meizul Zuki ◽  
Mina Sihite Hutasoit
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Palm Olein ◽  
Smoke Point ◽  
The Other ◽  
Deep Frying ◽  
Frying Time ◽  
Frying Oils ◽  
End Use ◽  
Olein Oil

The objective of the study was to evaluate the changing pattern of free fatty acid (FFA) and smoke pints of packaged and standard palm olein oil in frying kerupuk jalin. The other objective was to determine the end use of both frying oils during deep fying of kerupuk jalin.  Continous deep frying with three replicates had been done for10 hours using special grade and regular frying oil without the addition of fresh oil during frying study.  The result indicated that The FFA content of both packaged and regular oils increased linearly with increasing frying time, up to 10 hours.   In addition, smoke point of the oils decreased linearly with increasing frying time.  Based on FFA of the oil, the packaged oil could last 1,4 longer than regular oil during frying of kerupuk jalin. 

Physicochemical Characteristics and Thermal Stability of Perilla Seed Oil of Indian Origin

2021 ◽  
pp. 501-511
Author(s):  
Akriti Dhyani ◽  
Priyanka Prajapati ◽  
Rajni Chopra ◽  
Meenakshi Garg ◽  
Priyanka Singh
Keyword(s):  
Thermal Stability ◽  
Seed Oil ◽  
Stability Index ◽  
Physicochemical Characteristics ◽  
Smoke Point ◽  
Edible Oil ◽  
Oil Stability Index ◽  
Cold Pressed ◽  
Thermal Stability Of ◽  
Perilla Seed

There is an increasing interest of food scientists in finding new alternatives to PUFA rich edible oil. Perilla seed oil (CPSO), an underutilized oilseed, can be used as an edible oil source. Oil extracted by the cold-pressed method from perilla seeds gives a yield of 36.50%. This study reports the physicochemical properties, the oxidative and thermal stability of the cold-pressed perilla seed oil. The viscosity, specific gravity, refractive index, and smoke point of CPSO were 28 m.Pa.s, 0.92, 1.43, and 241 ℃, respectively. The peroxide, acid, iodine, saponification value, and unsaponified matter of CPSO were 4.81 meq O2/kg oil, 1.61 g KOH/kg oil, 132 g KOH/kg oil, 180 g I2/kg oil, and 0.64%, respectively. It consists of high α -linolenic acid (55.80% of total oil) followed by oleic acid (20.54%). The extracted oil is analyzed for its thermal stability (peroxide value, free fatty acids, p- anisidine value, totox value, and total polar compounds) and storage stability for 120 days in two different storage conditions (refrigerated and room temperature). Despite having high nutritional benefits, the oil stability index (0.50 h) of the perilla seed oil is low, limiting its utilization as a frying oil. Therefore, perilla seed oil requires process optimization to increase its stability during heating.

scholarly journals Assessment of the Properties of Rapeseed Oil Enriched with Oils Characterized by High Content of α-linolenic Acid

2019 ◽  
Vol 11 (20) ◽  
pp. 5638 ◽  
Author(s):  
Agnieszka Sagan ◽  
Agata Blicharz-Kania ◽  
Marek Szmigielski ◽  
Dariusz Andrejko ◽  
Paweł Sobczak ◽  
...  
Keyword(s):  
Erucic Acid ◽  
Oxidative Stability ◽  
Linolenic Acid ◽  
Peroxide Value ◽  
Rapeseed Oil ◽  
Raw Materials ◽  
Acid Value ◽  
Oil Mixtures ◽  
Lower Ratio ◽  
Cold Pressed

Functional foods include cold-pressed oils, which are a rich source of antioxidants and bioactive n-3 and n-6 polyunsaturated fatty acids. The aim of this study was to assess the quality of rapeseed oils supplemented with Spanish sage and cress oils. Seven oil mixtures consisting of 70% of rapeseed oil and 30% of sage and/or cress oil were prepared for the analyses. The oil mixtures were analyzed to determine their acid value, peroxide value, oxidative stability, and fatty acid composition. In terms of the acid value and the peroxide value, all mixtures met the requirements for cold-pressed vegetable oils. The enrichment of the rapeseed oil with α-linolenic acid-rich fats resulted in a substantially lower ratio of n-6 to n-3 acids in the mixtures than in the rapeseed oil. The mixture of the rapeseed oil with the sage and cress oils in a ratio of 70:10:20 exhibited higher oxidative stability than the raw materials used for enrichment and a nearly 20% α-linolenic acid content. The oils proposed in this study can improve the ratio of n-6:n-3 acids in modern diets. Additionally, mixing the cress seed oils with rapeseed oil and chia oil resulted in a reduction in the content of erucic acid in the finished product. This finding indicates that cress seeds, despite their high content of erucic acid, can be used as food components. The production of products with a positive effect on human health is one of the most important factors in the sustainable development of agriculture.

scholarly journals Thermo-degradative changes of rapeseed and sunflower oils during deep-frying French fries

10.5219/1080 ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 138-149
Author(s):  
Lucia Zeleňáková ◽  
Mária Angelovičová ◽  
Marek Šnirc ◽  
Jana Žiarovská ◽  
Stanislav Kráčmar ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Peroxide Value ◽  
Sunflower Oil ◽  
Rapeseed Oil ◽  
Acid Value ◽  
French Fries ◽  
Deep Frying ◽  
Frying Process ◽  
Sunflower Oils ◽  
Initial Content

The purpose of this study was to investigate changes in TPCs, acid value and peroxide value as well as fatty acids composition in edible oils during french fries production. Lower TPCs content was found in rapeseed oil (3.3%) and the threshold (24%) was achieved on the fourth day. The total time for the deterioration of deep-frying rapeseed oil was 23½ hours. On the contrary, in fresh sunflower oil at the first day was TPCs content 5.5% and the limit of 24% was reached on the third day. The total time for the deterioration of deep-frying sunflower oil was 17½ hours. The results indicated significant differences (<0.05) in TPCs content between rapeseed and sunflower oils during deep-frying process. At the beginning of deep-frying French fries in rapeseed oil, the acid number was 0.374 mg KOH.g-1 and 1.271 mg KOH.g-1 at the fourth day of deep-frying. The measured peroxide value was 4.3 mEq O2.kg-1 at the beginning and at the end of deep-frying 10.5 mEq O2.kg-1. The initial peroxide and acid values were higher in sunflower oil compared with rapeseed oil, respectively. It should be note, then the acid values and peroxide values, respectively, in the two fresh oils used in this study were below the limit of refined oil according to Slovak legislation (peroxide value - not more than 10 mEq O2.kg-1, acid value - not more than 0.6 mg KOH.g-1). However, detected values varied during deep-frying process. Monounsaturated fatty acids were predominantly observed in fresh rapeseed oil (61.22%) wherever in sunflower oil they were much lower (29.77%). A slight increase of MUFA was found in both oils. The initial content of saturated fatty acids in rapeseed oil was 6.94%, in fresh sunflower oil was observed slightly higher content of SFA (10.37%). The major groups of fatty acids in fresh sunflower oil were polyunsaturated fatty acids (PUFA) which have in principle a significant effect on oil deterioration. A slight decrease of PUFA was observed in both oils throughout the frying period. The content of PUFA was reduced by about 9.42% in rapeseed oil and by 10.8% in sunflower oil. The initial content was 28.14% and 58.91%, respectively.

Comparison of physicochemical properties of edible vegetable oils commercially available in Bahir Dar, Ethiopia

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Physicochemical Properties ◽  
Vegetable Oils ◽  
Relative Viscosity ◽  
Acid Value ◽  
Smoke Point ◽  
Refractive Indices ◽  
Bahir Dar ◽  
Icp Oes ◽  
Saponification Value ◽  
Oil Sunflower

The physicochemical properties of six imported and one locally produced edible vegetable oils (soybean oil, sunflower oil, sunlit oil, hayat oil, avena oil, USA vegetable oil and Niger oil) purchased from Bahir Dar city, Ethiopia, were examined for their compositional quality. All the oil samples were characterized for specific gravity, moisture content, color, relative viscosity, refractive indices, ash content, peroxide value, saponification value, smoke point, acid value, free fatty acid value and trace metals contents using established methods. The result clearly indicates that some of the oil samples exhibited unacceptable value when compared with physicochemical parameters recommended by the Codex Alimentations Commission of FAO/WHO and the specification of Ethiopian standards. The contents of nickel (Ni), copper (Cu) and iron (Fe) in seven samples were determined using ICP-OES and their concentrations were found in the range of 1.8-20.4, 45.8-82.2 and 136.04-445.0 mg/kg, respectively.

Comparison of Bioactive Compounds of Matricaria recutita Extracted by Ultrasound and Maceration and their Effects on Preventing Sunflower Oil During Frying

2019 ◽  
Vol 15 (2) ◽  
pp. 156-164 ◽  
Author(s):  
Reza Farahmandfar ◽  
Maryam Asnaashari ◽  
Yegane Asadi ◽  
Batool Beyranvand
Keyword(s):  
Antioxidant Activity ◽  
Gallic Acid ◽  
Bioactive Compounds ◽  
Sunflower Oil ◽  
Radical Scavenging ◽  
Stability Index ◽  
Acid Value ◽  
Extraction Methods ◽  
Oil Stability Index ◽  
Matricaria Recutita

Background: It is important to study about the use of natural antioxidants as alternatives to synthetic ones due to the possibility of carcinogenic effects of synthetic antioxidants. This study is comparing the effect of the ultrasound-assisted and maceration extraction methods on antioxidant activity of Matricaria recutita. Methods: Bioactive compounds including phenolic, tocopherol, flavonoid and tannins and antioxidant activity of the extracts were evaluated. Moreover, extracts obtained from ultrasound and maceration methods were added to sunflower oil without any antioxidants at level of 200, 500 and 800 ppm, after that samples were heated at 180°C. Oxidation of the samples were evaluated after 0, 4, 8, 12, 16, 20 and 24 hours by measuring Peroxide Value (PV), Conjugated Diene (CD), Iodine Value (IV), Carbonyl Value (CV), Total Polar Compounds (TPC), Oil Stability Index (OSI), Color Index (CI) and acid value (AV). Results: The result showed total phenol (42.90 mg gallic acid/g extract), tocopherol (120.46 &#181;g &#945; - tocopherol/ml extract), flavonoid (2.64 mg/100 g extract) and tannins (3.89 mg gallic acid/g extract) of ultrasound extracts were higher than maceration extracts. Antioxidant activity of the extract was evaluated by DPPH assay which indicated 800 ppm of the Matricaria recutita extracted by ultrasound was the highest radical scavenging ability. Conclusion: Result indicated both ultrasound and maceration extracts could increase the oil oxidative stability but could not increase compared to BHA. In most cases, the extract samples by ultrasound had a better effect on stabilizing of sunflower oil during frying.

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 Oil for Deep Frying in Foods and Changes Acidity on Various Kind of Oils after Frying

2018 ◽  
Vol 2 (3) ◽  
pp. 86
Author(s):  
Puminat W. ◽  
Teangpook C.
Keyword(s):  
Fatty Acid ◽  
Low Temperatures ◽  
Statistical Data ◽  
Rice Bran Oil ◽  
Acid Value ◽  
Deep Frying ◽  
Significant Difference ◽  
Long Time ◽  
Short Time ◽  
Fried Oil

<p><em>Human eat a lot of highly acidic and oxidant foods. Acid chemicals and oxidants in food cause harmful to the health. Acid value, free fatty acid and polarities of the fried oil change during cooking for food. Statistical data of fried oils estimate and systematize on three recipes of food (</em><em>Doughstick</em><em>, Fish cake and Fried chicken). Their recipes are on the best of sensory evaluation.</em><em> In each food recipes are selected from market and evaluated by traditional and popular merchant. In the sampling, the experimental model is planned by trial RBCD with factorial 3 × 2 × 3. The use of three type oil, two level temperature and three sampling collector are treated on experiments with three recipes. They showed that palm olien oil can change a higher pH than soybean oil and rice bran oil by a statistically significant difference at 95% confidence level<strong>.</strong> Deep frying by high temperatures and short time have change a quality oil less than low temperatures and long time. Frying in larger quantities and a longer period can change the more acidity and polarities. Quality foods for flavor and healthy oil must no more high and low temperature in cooking.</em></p>

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