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

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.

Identification of best fit crude oil of upper Assam basin for pipeline transportation

This paper attempts to identify a crude oil (CO) from eight different CO samples with a wide range of oAPI gravity from 13 to 43 belonging to Upper Assam Basin, India, to formulate the identified CO for pipeline transportation. Studies were conducted to understand the physical, rheological, and viscoelastic properties of the CO samples where physical properties included pour point (PP) and oAPI gravity, the rheological properties included viscosity (η), kinematic viscosity (K.V.), viscosity gravity constant (VGC), shear stress (τ) and shear strain (γʹ) and the viscoelastic properties were elastic modulus (G)' and viscous modulus (G''). This research aims at achieving PP < 9 °C for CO for the ease of flow through pipeline even during the extreme winter season in Assam when the ambient temperature drops below 10o C. SKO in 0%, 5%, 10%, and 15% was added with all CO samples to determine the physical, rheological and viscoelastic properties at 30 °C, since PP of most of the CO samples was near 30 °C. However, the important properties of SKO, i.e. smoke point, flash point and boiling point, were not addressed here as SKO was used for improving flowability through pipeline. Correlation coefficients (CC) were determined using CORREL function in Microsoft Excel to investigate the relationship between oAPI gravity and the other properties for all the CO samples to identify the best fit CO. CO3 and CO8 were identified from the relationships as the most desired CO samples and CO3 was obtained as the best fit CO for the pipeline transportation.

Application of OXITEST for Prediction of Shelf-Lives of Selected Cold-Pressed Oils

Introduction: Due to the enhanced awareness of consumers concerning healthy foods, homemade expeller-pressed oils have become popular worldwide. However, an extended storage period may lead to oxidization of the oil and exposure to hazardous byproducts by consumers.Methods: In this study, 10 pressed oil samples prepared from common oilseeds using a small-scale expeller oil press were analyzed by OXITEST with a sample amount of 5 g of oil and an oxygen pressure of 800 kPa under accelerated conditions for shelf-life projections. The oil properties were investigated, including the recovery, smoke point, acid value, iodine value, “fatty acid composition, and contents of pigments and tocopherols”.Results: The autoxidation reaction of various expeller-pressed oils under an accelerated testing system followed zero-order Arrhenius kinetics (R2 &gt; 0.99). Shelf-lives of the pressed oils at 25°C were estimated by extrapolation to range 105~1,089 days. The obtained shelf-lives were significantly correlated with log induction period (IP) values (r &gt; 0.81, p &lt; 0.05) and unsaturated fatty acids (UFAs) (r &lt; −0.69, p &lt; 0.05), but not with the iodine value, acid value, or smoke point. Scatter diagrams between shelf-lives and UFAs suggested that these pressed oils could be grouped by two linear regression curves (r &gt; 0.98, p &lt; 0.05). The predictive equations using multiple linear regression are presented herein, with predictor variables of UFAs and an unspecified item involving potential influencing factors such as tocopherol contents (r &gt; 0.88, p &lt; 0.05).Conclusions: Our findings first revealed that the UFA portion was partially correlated with the shelf-lives of selected expeller-pressed seed oils as estimated by the OXITEST. The derived equations can be applied for shelf-life predictions of expeller-pressed oils stored under dark ambient conditions based on the fatty acid profile.

Physical, chemical, and nutritional quality parameters of three different types of oil: determination of their reusability in deep frying

Deep frying is the process of immersing food in hot oil at a temperature of approximately 180°C. During deep frying, different chemical reactions are taking place, resulting in changes in the physicochemical properties of the frying oil, eventually leading to harmful health effects on the consumers. Nevertheless, based on economic feasibility, both the domestic and industrial levels tend to repeatedly use edible oils for deep frying. Thus, the current study aimed to evaluate physicochemical and nutritional parameters of commercially available coconut oil, palm oil and sunflower oil and to investigate the effect of repeated deep frying for the physicochemical and nutritional parameters of the studied oil samples. Thereby, the optimum number of frying cycles for each type of oil was also investigated. In order to achieve that, using coconut, palm and sunflower oils, potato and fish were fried separately for five repeated frying cycles. As per the results, regardless of the frying material, the relative density, colour, peroxide value, free fatty acid value of coconut oil, palm oil, and sunflower oil were increased significantly with increase the number of frying cycles whereas the smoke point and moisture content was found to be significantly decreased. In contrast, the number of cycles suitable for repeated frying is varying upon the frying material. Accordingly, coconut oil has proven to be used for three frying cycles of potato and five frying cycles of fish: palm oil for one frying of potato and two fryings of fish without adversely altering their physicochemical and nutritional properties. Conferring to the obtained results, the use of unsaturated oil like sunflower oil on repeated frying is not recommended.

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

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).

Applied Studies on Application of Capric/Caprylic MCT Oils in Food Industries

Non healthy oils & fats consumption in foods is the major reason of obesity in human beings. Common cooking oils & fats are composed of medium and long chain triglycerides. Each triglyceride consist of fatty acids called medium and long chain fatty acids abbreviated as (MCFAs & LCFAs). The ratio of LCFAs is mostly higher than the MCFAs in common cooking oils to be to be suitable for heat stress applications like cooking and frying. On the other side there is natural dietary fats are rich in Medium-chain fatty acids (MCFAs) like coconut oil and dairy fats. Also there are synthetic medium-chain triglyceride (MCT) oils which are synthetized by a processes called fractionation that extracts the MCFAs as caprylic and capric acid from the other fatty acids in the coconut or palm kernel oil. The MCFAs, shows substantial metabolic advantage compared to LCFAs. MCFAs are a preferred source of energy (b-oxidation). The last 20 years studies confirmed the potential of MCFAs to reduce body weight and may reduce fasting lipid levels more than oils rich in LCFAs. The same is true for glucose levels. In this study, the authors did chemical and instrumental studies on dietary structured MLCT and non-structured MCT/LCT cooking oils which were used for producing for weight reduction and obesity control purpose Capric /caprylic MCT oil was used as a source of MCFAs for producing of novel. Different sources of long-chain triglycerides (LCFAs) have been used including sunflower oil (SFO), Canola oil(CNO), high oleic sunflower oil (HOSFO), palm oil (PO) and double fractionated palm olein (DFOlein). The following techniques have been used for preparation of structured and non structured cooking oils in this study : 1-Physical blending. 2 - Chemical interesterification in a multipurpose batch reactor. 2- Enzymatic interesterification using immobilized Lipase enzyme in pilot scale packed bed reactor (PBR). Different analytical and instrumental techniques were used in this study including Gas chromatography (GC), high-performance liquid chromatography (HPLC), Differential scanning calorimeter (DSC), Rancimate, and smoke point tester. The study shown that the non-structured MCT/LCT oils gave reasonable heat stability, higher smoke points compared the structured MLCT oil which make it more suitable for cooking and frying applications. The chemical and enzymatic interesterification (CIE & EIE) technique yield a real structured MLCT oil which is more effective in caloric reduction and obesity control purpose during long term consumption in dietary foods, however, due to its much lower smoke point compared to its relative LCFAs oil so it will be suitable only for cold applications like salad dressing and other culinary applications. But not suitable for heat stress applications like deep or shallow frying.

Analytical Formulation-Based Soot Modelling in Ethylene Laminar Jet Diffusion Flames

Soot volume fraction predictions through simulations carried out on OpenFOAM® are reported in diffusion flames with ethylene fuel. A single-step global reaction mechanism for gas-phase species with an infinitely fast chemistry assumption is employed. Traditionally soot formation includes inception, nucleation, agglomeration, growth, and oxidation processes, and the individual rates are solved to determine soot levels. However, in the present work, the detailed model is replaced with the soot formation and oxidation rates, defined as analytical functions of mixture fraction and temperature, where the net soot formation rate can be defined as the sum of individual soot formation and oxidation rates. The soot formation/oxidation rates are modelled as surface area-independent processes. The flame is modelled by solving conservation equations for continuity, momentum, total energy, and species mass fractions. Additionally, separate conservation equations are solved to compute the mixture fraction and soot mass fraction consisting of source terms that are identical and account for the mixture fraction consumption/production due to soot. As a consequence, computational time can be reduced drastically. This is a quantitative approach that gives the principal soot formation regions depending on the combination of local mixture fraction and temperature. The implemented model is based on the smoke point height, an empirical method to predict the sooting propensity based on fuel stoichiometry. The model predicts better soot volume fraction in buoyant diffusion flames. It was also observed that the optimal fuel constants to evaluate soot formation rates for different fuels change with fuel stoichiometry. However, soot oxidation strictly occurs in a particular region in the flame; hence, they are independent of fuel. The numerical results are compared with the experimental measurements, showing an excellent agreement for the velocity and temperature. Qualitative agreements are observed for the soot volume fraction predictions. A close agreement was obtained in smoke point prediction for the overventilated flame. An established theory through simulations was also observed, which states that the amount of soot production is proportional to the fuel flow rate. Further validations underscore the predictive capabilities. Model improvements are also reported with better predictions of soot volume fractions through modifications to the model constants based on mixture fraction range.

Cooking with Extra Virgin Olive Oil

Mediterranean cultures have used Extra Virgin Olive Oil (EVOO) as the only source of cooking oil for centuries, with their diet showing the highest amount of scientifically proven health benefits. However, there is a common misconception that EVOO is not suitable for cooking given its relatively lower smoke point, despite no scientific evidence that support this. This chapter aims to provide an overview of how EVOO is healthier, safer, and more stable to cook with than other common edible oils. Furthermore, this chapter aims to present EVOO’s suitability for use on Teflon coated pans, which is another common myth.

Physical and chemical properties of tigernut oil as influenced by variety and method of extraction

This study was carried out to investigate the physical and chemical properties of tigernut oil as influenced by variety and methods of extraction. Oil was extracted from yellow and brown varieties of tigernut using mechanical screw press and N-hexane, and it was characterized for physical and chemical composition. The moisture content, acid value, free fatty acid, iodine value, saponification value and peroxide value for tigernut oil from extraction methods ranged from 2.97 to 3.30%, 0.28 to 0.56mgKOH/g, 0.55 to 1.12g/100g, 66.11 to 69.75gI/100g, 174.93 to 210.06mgKOHg and 0.27 to 0.56MgH2O2, respectively. The range of values for specific gravity, percentage impurity, cloud point, smoke point and melting point are: 0.64 to 0.99g/ml, 0.15 to 0.24%, 9.00 to 25.5°C, 170.5 to 204.5°C and 18.0 to 28.5°C, respectively. However, the study showed that both the physical and chemical composition of tigernut oil were affected by the extraction methods used in this study.

Comparative Analysis of the Physicochemical Characteristics, Phytochemical Components and Fatty Acid Profile of Avocado Pear (Persea Americana L) Pulp and Seed Oil

The physiochemical properties, phytochemical content, and fatty acid profile of Avocado pear (Persea americana) pulp and seeds oils were investigated. The pulp oil was extracted using the hot water flotation method while the seed oil was extracted by the soxhlet extraction method. Extracted oils were analyzed. The pulp oil was emerald green while the seed oil was brownish red in colour. Pulp oil has significantly higher blue (27B) on Lovibond scale. The oil yield, smoke point and flash point of the pulp oil were 28.26%, 171.00 °C and 201.67 °C respectively. Which were higher than 13.64%, 100.00 and 130.66 °C seen in the seed oil. Iodine value, FFA, peroxide value and saponification value of the pulp oil were respectively 50.70 g/100 g, 0.53%, 1.10 mEq/kg and 218.66 mgKOH/g while those of the seed oil were 40.68 g/100 g, 2.85%, 2.16 mEq/kg and 198.31 mgKOH/g respectively. Saponins, alkaloid, phenol, tannin, and oxalate content of the seed oil were significantly higher than those of the pulp oil, with respective values of 12.23, 1.06, 5.06, 3.05 and 10.07 mg/100 g. Flavonoid was however higher in the pulp oil, at 6.20 mg/100 g. avocado pulp oil contained 43.23% oleic acid, 19.78% linoleic acid. It contains only 35.31% total saturated fatty acids. The seed oil was shown to contain 55% palmitic acid, as the predominant saturated fatty acid and contained a total of 69% saturated fatty acids. It is recommended that avocado seed oil be refined before use for culinary purposes.