Higher Peroxide Value Research Articles

Effect of curcumin loaded in nanoemulsion basil seed gum coating on the reduction of acrylamide and oil absorption in fried potato strips

Frying is one of the oldest cooking methods, widely used to prepare crispy and flavorful foods. However, a significant concern with fried foods is the high amount of oil absorption. The application of edible coatings is a common approach to reducing oil absorption in fried potatoes. This study examines the effects of basil seed gum (BSG) edible coatings at three concentrations (1 %, 1.5 %, and 2 %), with and without curcumin nanoemulsion, on the characteristics of fried potato strips. Various parameters, including coating efficiency, moisture content, oil absorption, oil oxidation, acrylamide formation, and color indexes of the fried potatoes, were evaluated. The curcumin nanoemulsion coatings exhibited nano-sized particles (ranging from 119.2 to 150.5 nm) with a negative zeta potential and encapsulation efficiency above 60 %, displaying shear-thinning behavior. Scanning electron morphology analysis confirmed the encapsulation of curcumin within the coating structure. The highest moisture content (6.17 %), frying efficiency (50.17 %), and lowest oil absorption (25.94 %) were observed when the 2 % basil seed gum coating with nanoemulsion was used. The highest peroxide value (4.88 meq O2/kg), thiobarbituric acid (TBA) value (0.142 mg MDA/kg), and acrylamide formation (1473.5 µg/kg) were recorded in the uncoated control samples. Regarding color indexes, the uncoated control sample exhibited the highest lightness (L* = 63.1) and lowest yellowness (b*=28.7). Sensory evaluation indicated that potato strips coated with 1.5 % BSG containing curcumin nanoemulsion received the highest sensory scores. Utilizing BSG edible coating with curcumin nanoemulsion for coating potato strips can enhance the nutritional value and sensory properties of fried potatoes, making it a promising approach for improving product quality.

The comparison of compositional quality of milk and physicochemical properties of milk fat of indigenous cattle breed of Sri Lanka with locally reared pure European cattle breeds

As an essential dietary ingredient, milk fat (MF) has a major impact on the nutritional value, economics, and physical and chemical characteristics of milk and dairy products. The purpose of this research study was to examine and contrast the compositional quality of milk and physicochemical characteristics of milk fat of the Sri Lankan indigenous cow breed with that of locally raised Ayrshire and Holstein-Friesian pure European cattle breeds. Three random samples of milk from each breed of Ayrshire and Holstein-Friesian were gathered from the Nuwara Eliya district, and indigenous cow’s milk samples were collected from the Jaffna district, Sri Lanka. For compositional analysis, the Bulgarian MCCW Lactoscan equipment was used. To analyze physicochemical properties, a cream separator was used to separate the fat. The standard AOCS procedures were used to analyze physiochemical properties: Free fatty acid value (FFA), acid value (AV), saponification value (SV), peroxide value (PV), Polenske value (P) and Reichert Meissl value (RMV). The AOAC method was used to analyze the Refractive Index (IR). The evaluated parameters showed significant differences (p<0.05) according to Minitab one-way ANOVA. According to the study of the compositional quality of milk, locally bred pure European cow breeds had higher percentages of protein, fat, lactose, SNF, total solids and salts in milk than the native Sri Lankan bovine breed. The highest levels of PV (1.40 meqO2/kg), AV (0.67 mg KOH/g), and FFA (0.34) were found from milk fat of local indigenous cow breeds, whereas Holstein-Friesian milk fat had the lowest levels. The Ayrshire milk fat had the highest SV (236.50 mg KOH/g) and RMV (28.97), whereas the Indigenous cattle breed had the lowest. Holstein-Friesian milk fat had the greatest P (1.87), while Ayrshire milk fat had the lowest (1.57). In all the three breeds, IR (1.46) was nearly identical. This study revealed that, milk of locally raised pure European cattle breeds are better in quality than the local indigenous breed. Highest PV, AV and FFA observed in the local breed revealed that milk fat of local varieties are more susceptible to oxidation than that of locally raised European breeds.Keywords: Holstein-Friesian, Ayrshire, Indigenous cow breed, Milk composition, Physicochemical characteristics.

Effect of ozone gassing time and stirring duration on peroxide value, microbial decontamination, aflatoxin detoxification and sensorial characteristics of dried pistachios

Aflatoxin contamination in agricultural products such as pistachios threatens human health. Ozone has intense antimicrobial activity against microorganisms. The effect of ozone-treated time (3,4 and 5 hours) and stirring time (10, 15 and 20 minutes) on microbial, aflatoxin content, peroxide value, and sensory properties of aflatoxin contaminated pistachios were investigated in this study. The microbial test results also show a significant reduction of microbial load in ozone-treated samples. According to the results, ozone gas caused a significant reduction in aflatoxin levels in pistachio kernels. Aflatoxins B1, B2, G1, G2 and total which was 33.5, 1.5, 0.06, 0. 31 and 35.13 ppb in the control sample, reached 0 ppb after 5 hours of ozone-treatment (15 or 20 min). The results show that the longer the ozone gas is gasified, the higher the peroxide value. The lowest and highest peroxide value was observed in the control and the ozone-treated sample for 5 hours (stirring the samples every 20 minutes), respectively. All peroxide values were below the allowable limit (1 meq/kg). The results of sensory evaluation show that ozonation did not have a negative effect on the falvor, texture, and color score of pistachios, but only had a significant effect on the aroma of pistachios that were ozone-treated for 5 hours. According to results, 3 hours of ozonation and stirring of pistachios every 20 minutes is recommended as the best treatment for reducing microbial load, aflatoxin content, peroxide value and maintaining the sensory properties of dried pistachios.

Unveiling the power of bene (Pistacia atlantica) hull scum: Boosting oxidative stability with methanolic extract and ferrous ions

This study investigated the antioxidant potential of Bene hull methanolic extract (BHME) in mitigating lipid oxidation in vegetable oils across four systems (oil-in-water emulsions and bulk oils, both with and without Fe+2). The BHME's free radical-scavenging assay and ferric reducing abilities were compared with natural (α-tocopherol, CEX) and synthetic (BHT) antioxidants. The research analyzed different BHME concentrations (0, 400, 800, and 1600 ppm) and evaluated the effects of storage time on lipid oxidation, monitored through Peroxide Value (PV) and Carbonyl Value (CV) measurements. An array of statistical analyses, including ANOVA and a robust Support Vector Machine (SVM) model were employed to predict oxidation dynamics. The findings revealed that BHME demonstrated significant antioxidant activity, comparable to BHT, with both showing similar IC50 values (7.59 μg/ml and 7.45 μg/ml, respectively. In emulsions, PV increased 2.5 times at 800 ppm and 13 times at 1600 ppm compared to bulk oils. The presence of Fe+2 led to a 40 % higher PV in emulsions. CV values rose by 35 and 56 units at 800 and 1600 ppm, respectively, and increased six fold over the storage period. The SVM model showed high predictive accuracy, with R2 values exceeding 0.97. Response surface graphs indicated that storage time had a more pronounced effect on PV and CV than antioxidant concentration. This study highlights BHME's potential as an effective natural antioxidant, particularly in bulk oils, and demonstrates the utility of SVM for analyzing lipid oxidation. These findings provide valuable insights for improving the oxidative stability and shelf life of lipid-based food products.

Lipoxygenase activity in tropical fish: Changes during surimi processing and some biochemical characterization in lizardfish (Saurida tumbil).

The lipoxygenase (LOX) activity of major tropical fish used for surimi production, including threadfin bream (TB), lizardfish (LZ), and goatfish (GF), was measured in the gills, skin, and muscle. The highest LOX activity was observed in the LZ samples (p<0.05), with the gills exhibiting the greatest activity at 376.56U/mg (p<0.05). The highest peroxide value was detected in the TB samples, particularly in the gills (p<0.05). Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were the main polyunsaturated fatty acids in all the tissues and surimi. The total lipid and DHA contents of washed mince reduced considerably after the screw press process. Although LOX activity decreased during surimi production, a residual activity of 21.33U/g was observed in the finished surimi. LOX was partially purified and characterized from LZ gills. The purification was conducted using two successive chromatographic steps, Sephacryl S-200 and diethylaminoethyl (DEAE)-sepharose, resulting in a 3.52% yield and a 22.43-fold increase in purity. The optimum activity was found at 25°C and pH 7.5, with pH stability between 6.0 and 8.5. The relatively high thermal stability at 4°C-10°C suggested that LOX might contribute to fish lipid oxidation during cold storage. The enzyme was thermally inactivated at 60°C. The preferred substrate was EPA. LOX from the LZ gills was inhibited by 1mM ethylenediaminetetraacetic acid and activated by 1mM Fe2+, Na+, and Ca2+. PRACTICAL APPLICATION: Elucidating lipoxygenase activity and lipid oxidation in various tropical fish tissues, as well as understanding the characteristics of LOX, can help take appropriate postharvest actions to afford high-quality surimi.

The Pathology and Blood Biochemistry of Juvenile Lates calcarifer on Diets Contaminated With Mycotoxins, Histamines and Rancid Fats-A Case Study.

Mycotoxins, originating from contaminated raw materials or suboptimal feed storage, are a growing concern in tropical aquaculture. Common fungi such as Aspergillus spp. and Fusarium spp. produce mycotoxins including aflatoxin, fumonisin, deoxynivalenol and zearalenone. High doses or prolonged exposure (weeks) to low doses of these mycotoxins (< 20 μg/kg) can depress growth, immunity, and cause mortality. This study investigated poor growth and low survival in juvenile Asian seabass, Lates calcarifer fed two different diets (FM40 and ABS3) for 5 weeks. Analysis of these diets revealed high peroxide values, multiple mycotoxins and high histamine levels. Fish fed the FM40 diet, which was contaminated with aflatoxin B1 (13.2 μg/kg), aflatoxin B2 (1.9 μg/kg), deoxynivalenol (29.5 μg/kg), alternariol (2.2 μg/kg), elevated peroxide value (45.91 mEq/kg), and histamine (129.51 mg/kg) developed mild bile duct hyperplasia, depressed total serum proteins (50.40 ± 10.06 g/L), markedly elevated blood potassium (8.2 ± 0.18 mmol/L), and heavy iron deposits in splenic melanomacrophage centres (Perl's stain) indicative of increased haemolysis. The presence of multiple cytotoxic mycotoxins in FM40 diet could explain the increased haemolysis and elevated blood potassium. In contrast, fish fed the ABS3 diet, which had high histamine levels (210.05 mg/kg), exhibited protein-losing nephropathy with multifocal fibrin plugs (Martius scarlet blue stain) indicating acute renal damage, and elevated blood calcium and phosphorus levels. Histamine is metabolised and excreted through the kidneys and known to induce renal arteriolar constriction, disrupt glomerular filtration barrier and increase permeability resulting in protein loss. This study shows that blood biochemistry and histopathology are useful diagnostic tools for assessing the impact of mycotoxins and histamines on fish health.

Physicochemical Properties of Different Melon Seed Oils Dried at Different Temperatures

In this study, the effect of the drying process on the quality of oils obtained from different melon seeds was investigated. The seeds of two different melon varieties (Kırkağaç, Hasanbey) were separated and dried in the oven at different temperatures (30, 50 and 70 °C). Moisture, 1000 grain weight, width, length, thickness, oil yield, free fatty acidity, peroxide value, color values (L*, a*, b*), and total phenolic substance amounts and fatty acid composition were examined. The average of initial moisture values was 6.42% and 5.48%. The drying process was carried out until the moisture rate of melon seeds reached 1%. The average of most values of the cores varied from 4.55-5.16 mm, length 12.82-13.18 mm, thickness 1.21-1.38 mm and 1000 grain weights varied from 52.40-45.70 g. The amount of total phenolic substances of Kırkağaç melon seed oil was found in the range of 584-691 mg GAE /kg, and Hasanbey melon seed oil in the range 780-840 mgGAE / kg. The amount of total phenolic substance decreased with the applied heat treatment. The peroxide values of the oil obtained from Kırkağaç and Hasanbey beans in terms of meqO2 / kg varied between 6.9-8.4 and 7.2-9.1, respectively. The highest peroxide value was observed in oil obtained from beans dried at 70°C in both varieties. It has been observed that oleic and palmitic acids are also followed by linoleic acid compared to fatty acid composition compared to other fatty acids. According to the results obtained, it was determined that the most effective drying temperature was 50°C in terms of efficiency and quality.

Evaluating Extraction Methods for Caffeine Content in Gayo Arabica Coffee Oil through Gas Chromatography-Mass Spectroscopy

This study aims to determine physicochemical properties, and caffeine analysis of green bean coffee essential oil (GBCEO) and roasted bean coffee essential oil (RBCEO) by maceration and soxhlet extraction methods. The results indicated that RBCEO by maceration method have higher percentage of yield compared to GBCEO. By the same to soxhlet extraction method, RBCEO also showed higher percentage of yield compared to GBCEO. The refractive index of the GBCEOm and GBCEOs have a lower acid value compared to RBCEOm and RBCEOs. The specific gravity obtained for GBCEOm, RBCEOm, GBCEOs, and RBCEOs ranged from 0.87 to 0.97. The results showed that GBCEOm has the highest saponification value followed by RBCEOs. GBCEOm has the highest iodine value followed by RBCEOs, while RBCEOm and GBCEOs have a similar iodine value. The peroxide value showed that GBCEOs, and RBCEOs by soxhlet extraction method have higher peroxide value. The GC-MS analysis revealed that GBCEOm has higher caffeine followed by GBCEOs with the percentages area of 9.31% and 7.36% respectively. Meanwhile RBCEOm has lower caffeine followed by RBCEOs with the percentages area of 7.36% and 4.28% respectively. This finding showed that GBCEO shows higher caffeine compound compared with RBCEO.

Variation in the Composition and Quality of Nigella sativa L. Seed Oils-The Underestimated Impact on Possible Health-Promoting Properties.

Nigella sativa L. (black cumin) is one of the most investigated medicinal plants in recent years. Volatile compounds like thymoquinone and unsaponifiable lipid compounds are crucial functional components of this oil. Unfortunately, the composition of oils and their quality indicators are ambiguous both in terms of identified compounds and value ranges. Thirteen oils were extracted with hexane from black cumin seeds grown in India, Syria, Egypt, and Poland and analyzed for their fatty acid composition, unsaponifiable compound content and volatile compounds. Oils were also subjected to quality tests according to standard methods. The fatty acid composition and sterol content/composition were relatively stable among the tested oils. Tocol content varied in the range of 140-631 mg/kg, and among them, β-tocotrienol and γ-tocopherol prevailed. Oils' volatile compounds were dominated by seven terpenes (p-cymene, α-thujene, α-pinene, β-pinene, thymoquinone, γ-terpinene, and sabinene). The highest contents of these volatiles were determined in samples from Poland and in two of six samples from India. High acid and peroxide values were typical features of N. sativa L. oils. To sum up, future research on the medicinal properties of black cumin oil should always be combined with the analysis of its chemical composition.

Changes in volatile compounds and lipid oxidation in various tissues of Nile tilapia (Oreochromis niloticus) during ice storage.

Changes in the lipid oxidation and volatile compounds of a variety of tilapia tissues (Oreochromis niloticus) including the muscle, gills, and skin during ice storage were investigated by evaluating peroxide values (PVs), lipoxygenase (LOX) activity, fatty acid (FA) composition, and volatile substances. LOX activity and PV were determined in the gills, skin, and muscles throughout 9 days of storage in ascending order to the extended storage time. The highest level of LOX activity was found in the gills, whereas the highest PV was determined in the skin. FA content of all tissues decreased during the storage period. Oleic acid was the predominant monounsaturated fatty acid, whereas linoleic acid and docosahexaenoic acid were the main polyunsaturated fatty acids and omega-3 in all tissues. The fish gills were shown to have the highest level of volatile compounds followed by the skin and muscle, based on headspace solid-phase microextraction coupled with gas chromatography and mass spectrometry. Principal component analysis indicated gradual changes in the volatile compound composition with increasing storage time. 2-Butanone and nonanal in the muscle, 6-methyl-2-heptanone and 2-nonenal in the gills, and 1-heptanol, and 1-nonanol in the skin were found to be the potential freshness indicators. In addition, hexanal could be a general potential marker for measuring the degree of lipid oxidation in all tissues. PRACTICAL APPLICATION: Understanding the volatile compound formation related to lipid oxidation within storage time at various tissues of tilapia could be critical to the side-stream processing to yield the desired quality.

Lipid and Volatile Profiles of Various Goat Primal Cuts: Aspects of Nutritional Value and Flavor/Taste Attributes.

The lipid and volatile profiles of goat primal cuts (shoulder, rib, loin, breast, and leg), as well as their potential impact on nutritional and flavor/taste attributes, were investigated. The breast cuts had the lowest protein but the highest fat content. Triacylglycerol was the predominant lipid in all cuts (82.22-88.01%), while the breast cuts had the lowest triacylglycerol and the highest diacylglycerol and free fatty acids. Also, the highest unsaturated fatty acid (UFA), both monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA), was obtained in the breast cuts. These findings correlated well with the highest peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) value. The volatile profiles of the various grilled cuts indicated that the breast and leg cuts had similar volatiles, with higher amounts of alcohol, aldehyde, ketone, and ester than others, which could explain the flavor oxidation by lipid and off-flavors in spoiled meat. While the shoulder, rib, and loin cuts had higher amounts of nitrogen-containing compounds. The highest sulfur-containing and hydrocarbon compounds were also observed in the shoulder cuts, which are mainly formed during the Maillard reaction and responsible for the cooked meat flavor. This investigation revealed that each cut of goat meat has a varied composition, especially in lipids and volatile compounds. Thus, meat quality differs in terms of nutritional aspects and flavor/taste characteristics, enabling consumers to select nutritious or proper cuts for their cooking to achieve the most satisfaction from goat meat consumption.

Comparative study of virgin olive oil from Moroccan Picholine cultivars in TADLA perimeter -Morocco

Olive oil, extracted from olive fruits (Olea europaea), is renowned for its distinctive flavour, nutritional richness and health benefits. The aim of this comparative study is to analyze olive oil from several TADLA perimeter units, including Province of AZILAL, FQUIH BEN SALAH, BENI MELLAL, ZAOUIT CHEIKH, and BRADIA. The oil under investigation was extracted from olives of the Moroccan Picholine variety, by a discontinuous system including grinding, pressing and decanting. Significant variations were found at the values of the studied parameters. The results of our study showed that Olive oil from FBS and BM are classified as an extra virgin olive. However, olive oils from ZC, BR and AZ are classified as virgin olive oil. Sample from FQUIH BEN SALAH province had the lowest Free Fatty Acids (FFA) and peroxide values 0.236% oleic acid and 3.434 méqO2/Kg respectively. While the highest FFA value found was the olive oil obtained from AZILAL (1.084% Oléic Acid) and the highest Peroxide value was obtained in the sample from BRADIA (8.108 méq O2/Kg). E232, E270 and delta K values of all samples were under the limit fixed by IOC for virgin olive oil. Polyphenols content of ZAOUIT CHEIKH, FQUIH BEN SALAH and BRADIA oils are relatively high with values equal to 1.347, 1.082, and 1.141mg GA/100ml extract respectively. DPPH test showed that ZAOUIT CHEIKH oil had the greater antioxidant capacity.

Physical properties, dietary fibre profile and peroxide value of biscuit produced from wheat-Tigernut flours with avocado paste as fat substitute

This study investigated the effect of replacing fat with avocado paste on the physical properties, dietary fibre profile and peroxide value of wheat-tigernut biscuits. Whole tigernut was processed into flour and blended with wheat flour at three different levels; 10%, 20% and 30% weight basis into two parts. The first part of the composite (T10, T20, and T30) and control sample (100% wheat flour, T00) were baked into biscuit using margarine, while in the second batch (AT10, AT20, and AT30), margarine was replaced with avocado paste (100%). The biscuit samples were analysed for physical properties, dietary fibre profile and peroxide value using standard procedures. Data were subjected to Analysis of variance, and means were separated using Duncan’s Multiple Range Test at p&lt;0.05. Biscuits baked with avocado paste had higher spread ratio (6.98 – 7.19) and weight (17.39 – 17.51 g) than samples baked with margarine. Break strength of control sample was higher (185g) compared to biscuit samples baked with margarine (182.70 – 175.81 g), but lower than biscuits baked with avocado paste (182.70 – 175.81 g). Biscuits baked with avocado had higher dietary fibre profile of 7.49 to 7.84% and 5.72 to 5.82% for insoluble and soluble fibres. Biscuits containing avocado paste had higher peroxide values (1.91 to 2.56 meq O2/kg) than samples containing margarine (1.67 to 2.18 meq O2/kg). Replacing avocado with margarine improved the physical properties and dietary fibre profile of the biscuits with no adverse effect on the peroxide value and could therefore, be exploited as a healthier shortening agent to enrich biscuits.

Effect of extraction methods on physical and chemical properties and shelf life of black cumin (Nigella sativa L.) oil

The herbaceous plant black cumin (Nigella sativa L.) has a variety of medical benefits. For therapeutic uses, effective utilization of black cumin oil (BCO) depends upon its functional groups. The objective of the current study was to investigate the physicochemical characteristics, extraction methods' effects, shelf-life, and functional groups of BCO. Mechanical, cold, and Soxhlet extraction methods were used to extract oil from seeds. Proximate analysis of black cumin seeds showed 20.37 % protein, 34.24 % fat, 6.86 % moisture, 7.02 % ash, and 31.51 % carbohydrate. The density of mechanically extracted oil (MEO), Soxhlet extracted oil (SEO), Cold extracted oil (CEO), Locally labeled oil (LLO) and Locally unlabeled oil (LUO) were 0.957 g/cm3, 1.151 g/cm3, 1.170 g/cm3, 1.068 g/cm3 and 1.066 g/cm3, respectively, whereas the refractive indices were approximately similar in all oil samples. In terms of color, CEO and MEO were respectively the lightest and reddest ones among the oils. Initially, free fatty acid (FFA) contents in MEO, SEO, CEO, LCO and LUO were 6.663 %, 6.041 %, 8.214 %, 8.458 %, and 7.573 % respectively, where the highest peroxide value (PV), iodine value (IV) and saponification value (SV) were found as 26.232 mEq O2/kg, 122.275 g I2/100 g and 201.282 mg KOH/g in LCO, CEO and LUO. respectively. By 14 weeks of storage FFA, PV and SV in MEO increased from 6.663 to 14.289 %, 23.508 to 32.229 mEq O2/kg and 196.207–202.629 mg KOH/g respectively while IV decreased from 122.275 to 117.319 g I2/100 g. FTIR analysis reveals the MEO mostly consists of unsaturated fatty acids (cis). The overall findings conclude that MEO remains consumable until 10 weeks indicating a better stability against oxidation and rancidity.

Microencapsulated polyphenol extracts from Georgia-grown pomegranate peels delay lipid oxidation in salad dressing during accelerated and ambient storage conditions.

Lipid oxidation is a major cause of quality deterioration in salad dressings. This study evaluated the effect of incorporating microencapsulated polyphenol extracts via spray drying from pomegranate peels (MPP) to delay lipid oxidation in Italian-style salad dressings (ISD) during accelerated (55°C) and ambient (25°C) storage conditions. ISDs, prepared at high (5000 rpm) and low (250 rpm) shear rates conditions, were formulated with unencapsulated polyphenol extracts from pomegranate peels (PPP), MPP, and/or grape seed extract (GSE). Lipid oxidation in ISDs was evaluated by measuring peroxide value (PV), iodine value (IV), and TBARS, stored in accelerated and ambient conditions for 21 days and 8 weeks, respectively. Tannis in extracts were measured via HPLC-DAD and the total hydrolyzable tannin content of PPP and MPP was 283.09 and 427.74 (mg/g extract), respectively. Condensed tannins were not detected in PPP and MPP but were found in GSE (348.53 mg/g extract). Salad dressings prepared at high shear rates had significantly (p < .05) higher emulsion stability than those homogenized at low shear rates. Mixing conditions did not affect the lipid oxidative stability of IDSs. Salad dressing stored under accelerated storage had higher lipid oxidation (higher PV, lower IV, and higher TBARS) after 21 days than IDSs stored under ambient conditions for 8 weeks. ISDs prepared with MPPP showed significantly (p < .05) lower lipid oxidation than the other ISDs at the end of the shelf life studies. Results from the accelerated storage suggested that incorporating MPP could have extended the shelf life of IDSs by 20% compared to using unencapsulated polyphenol extracts. The study demonstrated that MPP delays lipid oxidation in ISDs during storage more effectively than unencapsulated extracts. MPP may serve as a natural and effective functional food ingredient for controlling lipid oxidation in high-lipid and acidified foods.

Effect of refining on the quality of oils extracted by cold press from black cumin (Nigella sativa L.) seed and by solvent from its cake

SummaryBlack cumin seed oil, known for its bioactive compounds and health benefits, faces challenges due to its high peroxide value and free fatty acid content, limiting its applications. The study investigates oil extraction from black cumin seeds using cold pressing and solvent extraction. The oil extraction yields were found to be 32% from the seeds and 13% from the cake. Subsequently, the study investigated the impact of different refining steps on the quality of these oils. The oil extracted from the cake exhibited higher free fatty acid, chlorophyll, and carotenoid contents compared to the oil extracted from the seeds, with increases of 84%, 73%, and 66%, respectively. Conversely, the peroxide value, total phenol, and thymoquinone content of the cake‐derived oil were lower than those of the seed‐derived oil, with reductions of 74%, 69%, and 95%, respectively. The refining process resulted in general reductions in peroxide value, free fatty acid, and p‐anisidine levels. However, no significant effect on the fatty acid composition was observed. The refining led to a decrease in the bioactive content, including total phenolic compounds (6%–68%), carotenoids (86%–85%), and thymoquinone (50%–90%). These results contribute to a better understanding of the potential applications and refining requirements for black cumin seed oil.

Physico-Chemical Analysis of Murchita and Amurchita Shadanga Ghrita

Background: Contagious diseases are the most common cause of death globally and Atisaar is one of them. More than 1 billion cases and at least 4 million deaths per year are attributed to diarrhoea worldwide. Ayurvedic literature has numerous uninvestigated medicines, Shadanga Ghrita is one of those classical herbal formulations used in the management of Atisaar, mentioned in the famous text Chakradatta. Preparation of this oleaginous dosage form is described as Sneha Kalpana, done by subjecting Ghrita to a particular pattern of heat-treated with 1/4th part Kalka (paste) and 4th part of Kwatha (decoction) of the respective drugs in equal proportion. Till date, no research work has been done on the study of Shadanga Ghrita. So the present study was planned to evaluate the Physio-Chemical analysis of Shadanga Ghrita with and without Murchana. Aim and Objective: Aim was to prepare the sample of Shadanga Ghrita with &amp; without Murchana and to evaluate both the formulations through pharmaceutical and analytical parameters. Material and Methods: Murchana of Ghrita was done as per Bhaishajya Ratnavali Jwara-rogadhikaar &amp; Shadanga Ghrita was prepared as per Sharangdhar Samhita. Result: All the Physico-chemical parameters of both the samples are within the reference range Conclusion: Murchita Shadanga Ghrita is better than Amurchita Shadanga Ghrita due to better taste, odor, low viscosity, high saponification &amp; high peroxide value.

Assessment of Quality and Efficiency of Cold-Pressed Oil from Selected Oilseeds.

In this present study, an oil press was used to process 200 g each of sesame, pumpkin, flax, milk thistle, hemp and cumin oilseeds in order to evaluate the amount of oil yield, seedcake, sediments and material losses (oil and sediments). Sesame produced the highest oil yield at 30.60 ± 1.69%, followed by flax (27.73 ± 0.52%), hemp (20.31 ± 0.11%), milk thistle (14.46 ± 0.51%) and pumpkin (13.37 ± 0.35%). Cumin seeds produced the lowest oil yield at 3.46 ± 0.15%. The percentage of sediments in the oil, seedcake and material losses for sesame were 5.15 ± 0.09%, 60.99 ± 0.04% and 3.27 ± 1.56%. Sediments in the oil decreased over longer storage periods, thereby increasing the percentage oil yield. Pumpkin oil had the highest peroxide value at 18.45 ± 0.53 meq O2/kg oil, an acid value of 11.21 ± 0.24 mg KOH/g oil, free fatty acid content of 5.60 ± 0.12 mg KOH/g oil and iodine value of 14.49 ± 0.16 g l/100 g. The univariate ANOVA of the quality parameters against the oilseed type was statistically significant (p-value < 0.05), except for the iodine value, which was not statistically significant (p-value > 0.05). Future studies should analyze the temperature generation, oil recovery efficiency, percentage of residual oil in the seedcake and specific energy consumption of different oilseeds processed using small-large scale presses.

Thermal stability of levopimaric acid and its oxidation products

Biofuels are renewable alternatives to fossil fuels. Levopimaric acid‒base biofuels have attracted increasing attention. However, their stability remains a critical issue in practice. Thus, there is a strong impetus to evaluate the thermal stability of levopimaric acid. Through thermogravimetry (TG) and a custom-designed mini closed pressure vessel test (MCPVT) operating under isothermal and stepped temperature conditions, we investigated thermal oxidation characteristics of levopimaric acid under oxygen atmosphere. Thin-layer chromatography (TLC) and iodimetry were used to measure the hydrogen peroxides generated by levopimaric acid oxidation. A high pressure differential scanning calorimeter (HPDSC) was used to assess hydroperoxide thermal decomposition characteristics. Gas chromatography-mass spectrometry (GC-MS) was used to characterize the oxidation products. The thermal decomposition kinetics of levopimaric acid were thus elucidated, and a high peroxide value was detected in the levopimaric acid. The decomposition heat (QDSC) and exothermic onset temperature (Tonset) of hydroperoxides were 338.75 J g−1 and 375.37 K, respectively. Finally, levopimaric acid underwent a second-stage oxidation process at its melt point (423.15 K), resulting in complex oxidation products. Thermal oxidation of levopimaric acid could yield potential thermal hazards, indicating that antioxidants must be added during levopimaric acid application to protect against such hazardous effects.

Impact of Washing with Antioxidant-Infused Soda-Saline Solution on Gel Functionality of Mackerel (Auxis thazard) Surimi.

Mackerel (Auxis thazard), a tropical dark-fleshed fish, has the potential to be used in the production of surimi. It is necessary to identify the optimal washing method to make better use of this species since efficient washing is the most important step in surimi processing to ensure maximal gelling and high-quality surimi. The purpose of this study was to evaluate the combined effect of cold carbonated water (CW) with NaCl and antioxidants in washing media, so-called antioxidant-infused soda-saline solution, on lipid and myoglobin removal efficacy, biochemical characteristics, gelling properties, sensory features, and the oxidative stability of mackerel surimi in comparison with unwashed mince (T1) and conventional water washed surimi (T2). Mackerel mince was washed with CW in the presence of 0.6% NaCl at a medium to mince ratio of 3:1 (v/w) without antioxidant (T3) or with the addition of 1.5 mM EDTA plus 0.2% (w/v) sodium erythorbate and 0.2% sodium tripolyphosphate (T4), 100 mg/L gallic acid (T5), and 5 mM citric acid containing 8 mM calcium chloride (T6). During the first washing cycle, the antioxidants were mixed into the washing medium. The second and third washing cycles were then completed with cold water. The yields of all treatments were roughly 75-83%, based on the gross weight of the raw mince. The pH of the surimi was in a range of 5.47-6.46. All of the surimi had higher reactive sulfhydryl (SH) content and surface hydrophobicity but lower Ca2+-ATPase activity than unwashed mince (p < 0.05). After washing, lipids decreased significantly (p < 0.05), accounted for a 65-76% reduction. The T2 surimi had the highest peroxide value (PV). T1 had the lowest conjugated diene value. T1 and T4 surimi had the lowest TBARS value (p < 0.05). A lower non-heme iron level was found in all antioxidant-treated samples than in T1. Washing can increase the redox stability of myoglobin regardless of the washing media, as seen by the relatively low metmyoglobin levels. According to the dynamic viscoelastic behavior, all surimi and unwashed mince underwent the same degree of sol-gel transition following heat gelation. T1 showed the lowest breaking force, deformation, gel strength, and whiteness (p < 0.05). Surimi made from T4 or T5 had the highest gel strength when both breaking and deformation were considered, but the latter's expressible drip was noticeably higher. Surimi gel appears to be stabilized against lipid oxidation, as demonstrated by low PV and TBARS levels, when produced with T4. Because of the low level of TBARS, all 10 panelists rated rancid odor as low (~1 out of 4), with no significant variations across treatments. Only treatments with T4 and T6 tended to have a lower fishy odor score as compared to unwashed mince. Scanning electron microscope demonstrated that surimi gels washed with all washing media exhibited microstructures that were very comparable, with the exception of the T6 treatment, which had big pores and aggregates. Based on the quality features, T4 appeared to be the optimal medium to enhance the gel functionality of mackerel surimi.