Oil Quality Research Articles

Non-contact identification of essential oils with IR sensors and analysis of components with an electronic nose

AbstractIn this study, the odour values of rosemary, mint, black cumin, lavender, and thyme oils were determined by an electronic nose working with an Arduino microprocessor. The components of the plants were compared with the sensor data, and the most sensitive sensors were determined by sorting according to the highest components. The study data indicated that the MQ3 sensor exhibited the highest sensitivity for thyme, black cumin, and lavender oils, which contain 63% carvacrol, 38% thymoquinone, and 36% linalool, respectively. Also, MQ7 was the most sensitive sensor for menthone (68%) in mint oil and eucalyptol (45%) in rosemary oil. In addition, a low-cost and non-contact device that works with an infrared sensor has been developed to detect the identity of the oil added into the vial. The study data showed that low-cost Arduino-based IR and odour sensors can determine the identity and component percentage of oils. The fact that the developed device can detect with 100 percent accuracy even in case of peppermint and rosemary oils, which are very similar in appearance, shows that the study data will be an inspiration for contactless determination of oil quality and type.

Experimental investigation on the oil extraction process for a novel underground oil storage method: Oil storage in salt cavern insoluble sediment voids

Large-scale underground oil storage is vital for addressing the energy crisis. Leveraging the insoluble sediment space at the bottoms of salt caverns for oil storage is particularly effective in high-impurity salt mines, enhancing oil storage capacity. The process of extracting oil from the sediment void is essential for utilizing this resource. Three experimental devices were developed to investigate this extraction process. We conducted experiments on oil extraction processes and rates for various oil types, analyzing weight changes and influencing factors. The sediment and water content in the extracted oil were also evaluated. Results indicated that extracting oil from the sediment void is feasible, yielding average recovery rates over 90.0 %. High-viscosity oil at 50 °C exhibited three stages: initial stability, a rapid rise, and final stability. Low-viscosity oil correlated with brine injection rates, displaying a rapid rise, stable phase, and subsequent decline. Petrolatum extraction was easier than diesel extraction, and ground temperature improved recovery rates. Changes in water and sediment content had minimal impact on oil quality. This research provides insights for large-scale underground energy storage.

Antioxidant activity, physico-chemical properties, and bioactive compounds of Nigella sativa seeds and oil impacted by microwave processing technique

Strongly anti-oxidant and medicinal, Nigella sativa L (NS) is utilized in conventional medicine to address a range of illnesses, including gastrointestinal, inflammatory and rheumatic illnesses. This study was carried out to investigate the effects of microwave processing on the physico-chemical properties of Moroccan-grown Nigella sativa seeds and oils, as well as to investigate the antioxidant qualities of black cumin oils under conditions of accelerated oxidation. The study's specific goal was to ascertain the effects of varying microwave power levels (500 and 750 W) and roasting times (5, 10, and 15 min) on the black cumin oils' quality indices, fatty acid and sterol content, carotenoid and chlorophyll levels, mineral profile, tocopherol amount, and overall antioxidant activity. To this end, the seeds of black cumin were roasted at two power levels (500 and 750 W) and for three different periods (5, 10, and 15 min) in a microwave oven. The obtained results show that the duration and the processing power did not significantly influence the amount of sterols and fatty acids. In contrast, the quality indices, physico-chemical properties, carotenoid and chlorophyll contents, mineral profile, and tocopherol amount were influenced by the microwave processing. A significant decline in the antioxidant activity was recorded from 45.01 ± 0.81 % (unroasted cumin seeds) to 4.32 ± 0.91 % (750 W/5 min). Based on these findings, the black cumin oil preparations should be handled carefully and the oil must be protected once extracted. The stability and preservation of antioxidants are crucial steps against pro-oxidant and inflammatory conditions that could favour cellular senescence and accelerate aging processes.

Inheritance and QTL mapping identified multi-effects loci for fatty acid related traits in peanut (Arachis hypogaea L.)

Peanut (Arachis hypogaea L.) is an important oil and edible protein crop. The fatty acid composition not only influences the quality of peanut oil but also impacts flavor, shelf life, and consumer health. Peanut oil comprises approximately 80% oleic acid (C18:1) and linoleic acid (C18:2), 10% palmitic acid (C16:0), and the remaining 10% includes stearic acid (C18:0), arachidic acid (C20:0), gadoleic acid (C20:1), behenic acid (C22:0), and lignoceric acid (C24:0). To unravel the genetic foundation of fatty acid content and delve into QTL localization, we utilized high-density SNP microarrays for genotyping the RIL population of ‘SunOleic 97R’ × ‘NC94022’. A genetic linkage map was constructed with 3141 SNP markers, covering a total genetic distance of 3051.81 cM. We identified 60 quantitative trait loci (QTLs) associated with fatty acids which distributed in 11 linkage group, with phenotypic variance explained (PVE) ranging from 1.37% to 44.92%. Notably, the QTL qFAT_A05.1 and qFAT_A08.1 are multiple-effect loci contributing to various fatty acid compositions. Moreover, we identified 15 haplotypes for the QTL qFAT_A05.1 and qFAT_A08.1 through genotyping 178 peanut germplasms. Haplotypes analysis in natural population confirmed the closely relationship of the QTLs with the content of oil, oleic acid, lignoceric acid, palmitic acid and behenic acid. This study serves as a valuable reference for selecting improved peanut genotypes with superior oil quality and desirable fatty acid composition.

An Examination of the Potential Hair Damage Caused by Coconut Oil’s Dark Side

The moisturizing and nourishing qualities of coconut oil, a popular hair care product, have been praised. On the other hand, an increasing amount of data indicates that using coconut oil incorrectly or excessively can harm hair. This paper attempts to provide an overview of the available data about the possible harm that coconut oil may cause to hair, including pore blockage, protein accumulation, and moisture imbalance. A thorough review of the literature shows that the high protein content and thick, greasy texture of coconut oil can lead to clogged pores, inflammation, itching, and hair loss in addition to weighted-down hair, frizz, and breakage of the hair. Moreover, overusing coconut oil can throw off the natural moisture balance of the hair, causing frizz, brittleness, and dryness. This review emphasizes the need to use coconut oil with carefully to prevent potential harm to hair and offers safe usage guidelines.

Physicochemical Characteristics and Antioxidant Activity of Some Algerian Extra Virgin Olive Oils (Olea europaea L.)

Background:: The present work was conducted to investigate the quality and antioxidant properties of some Algerian extra virgin olive oils (EVOOs). Objective:: In this paper, the physicochemical characteristics and antioxidant properties of four EVOOs of monovarietal samples (Chemlal) from East Algeria were studied. Methods:: Physicochemical characteristics, which include free acidity, peroxide index, saponification index, specific extinction coefficients, water content, refractive index, relative density, and chemical composition, in addition to their antioxidant activity, were investigated based on DPPH free radical-scavenging activity (DPPH-SA). Results:: The results of physicochemical and quality parameters proved that all samples are EVOOs with highly nutritious and health benefits for the consumer, as per the recommendation of the International Olive Council (IOC). The results showed that the olive oils from the southern arid region of Algeria (Sahara), have a high antioxidant activity than the samples from the Northern regions. Conclusion:: These findings revealed a significant influence of geographic location on the chemical characteristics and antioxidant activities of olive oil from the same cultivar (Chemlal). These olive oils from the arid Saharan region may be used as a functional food with great antioxidant potential.

Quality Evaluation of Argan Oil as a Food Product Using Ultrasonic Characterization

Abstract Start This study focuses on evaluating the quality of food-grade argan oil, an essential component of Moroccan cuisine, using experimental ultrasonic characterization. Variations in ultrasonic velocity and attenuation with temperature were exploited as significant parameters for quality control of argan oil. The results reveal an inverse correlation between ultrasonic velocity and temperature, providing a unique model for the studied samples of argan oil. The measurements also show that the acoustic attenuation of argan oil decreases with temperature, while it increases with the volumetric fractions of sunflower oil added to argan oil. The data collected during this experimental study demonstrate that the velocity of the mixture of argan oil and sunflower oil increases with rising temperature. It was observed that both ultrasonic parameters of this mixture are challenging to detect by ultrasound. Ensuring the reproducibility of measurements under the same conditions, reference graphs are established to detect adulteration, especially when considering blends of argan oil with sunflower oil.

The Influence of Weather Conditions on the Immortelle Volatile Constituents from Essential oil and Hydrosol with a Focus on Italidiones and Its Molecular Docking Anti-Inflammatory Potential

Objectives Immortelle has garnered global attention for its cosmetic, medicinal, and culinary applications worldwide. Apart from neryl acetate, α-pinene and γ-curcumene as the most important components for the estimation of the essential oil quality, in recent years a group of β-diketones, known as italidiones, appear as significant quality parameters. However, it is unknown how weather conditions (temperature and precipitation) influence their accumulation in essential oil and hydrosol, nor their anti-inflammatory potential. Methods This study investigates the chemical composition of immortelle essential oil and hydrosol over three successive years (2019/20, 2020/21, and 2021/22), by GC-FID and GC-MS analysis. In silico molecular docking model with Vascular Adhesion Protein-1 (VAP-1) was used for the simulation of the anti-inflammatory potential of italidiones, as well as other β-diketones present in immortelle essential oil and hydrosol. Results During the three-year trial, it was established that essential oil compounds such as α-pinene, neryl acetate, and italicene were positively correlated with temperature and negatively correlated with precipitation, as well as β-diketones and total italidiones. Moreover, trans-caryophyllene, γ-curcumene, and ar-curcumene were in negative correlation with temperature, and a slight positive correlation with precipitation. On the other side, in the hydrosol the content of both total β-diketones and total italidiones was strongly negatively correlated with temperatures, and positively correlated with precipitation, which was the opposite of essential oil. Additionally, findings indicated that italidiones could bind the human VAP-1 protein in the vicinity of the topiquinone and block its function. Conclusion Weather conditions affect variations in the accumulation of volatile compounds in essential oil and hydrosol, which in some cases can affect changes in olfactory characteristics, as well as criteria prescribed by standards, and even changes in biological activities. These results indicate that italidiones, as well as other β-diketones present in immortelle, may be responsible for its anti-inflammatory activity.

Assessment of overall remaining useful life of lubricants by integrating oil quality and performance

Effective lubricant health monitoring programs are essential for extending the lifespan of both the lubricant and machinery. An accurate and reliable remaining useful life (RUL) prediction is necessary for maintenance decision support. The degradation of used lubricating oil information trends evaluated using used oil analysis results is necessary. This study addresses the need for a comprehensive tool to consolidate oil analysis parameters and determine the remaining useful life (RUL) of used lubricating oil (ULO). A Performance Rating Index (PRI) was developed by integrating various oil degradation testing parameters, including membrane patch colorimetry for varnish and sludge potential, along with viscosity, foaming stability, water separability, air release properties, oxidation stability, rust prevention, and copper strip corrosion. The integration of routine and performance test results of a turbine oil at 25,480 operating hours exhibited a PRI of 48.5. Correlating with the ASTM degradation alarm limits of 50 %, the PRI results provide clear maintenance actions before the original equipment manufacturer's recommended overhaul. The PRI approach supports proactive maintenance by facilitating early oil replenishment, extending RUL, and reducing waste oil.

Pickering emulsion of pepper essential oil stabilized by Octenyl succinic acid starch: Characterization, in vitro release and anticancer activity.

Under high humidity and high temperature conditions, the quality of pepper essential oil easily deteriorates, and the oxidation of oil restricts its application, especially for the insolubility in water. This study investigated pepper essential oil encapsulated in Pickering emulsion with octenyl succinic acid starch, which was effectively able to reduce 100 times of the release rate. The smooth surface and complete particles of the emulsion were observed and no new chemical bonds were formed. The minimum particle sizes were 2.05µm and 1.89µm, when the Pickering emulsion was set to different storage conditions at pH 5 and 0.1M NaCl, respectively. During gastrointestinal digestion, the release of essential oils was effectively delayed in the Pickering emulsion and the digestibility of the emulsion was 16.93% in 120min. Compared with untreated cells, Pickering emulsion can effectively inhibit the proliferation of MCF-7 (52.71%). All these results indicate that OSA starch stabilized pepper essential oil can effectively increase solubility, improve stability, and expand the application range. Therefore, it can provide a theoretical basis for applications of pepper essential oil, especially for the functional drug application.

The Effect of Prawns Shell Carotenoprotein Insertion on the Quality and Oxidative Stability of Tuna Eye Oil

The oxidation of polyunsaturated fatty acids (PUFAs) reduces the nutritional value of fish oil supplements and poses health risks due to the formation of free radicals and oxidative compounds. Consequently, preventing or minimizing oxidation in these supplements is a critical concern in the production industry. Tuna eye (TE) oil, similar to other fish oils, is highly prone to oxidation, leading to the need for antioxidant enhancement. Carotenoprotein, rich in astaxanthin from shrimp shells, is a powerful natural antioxidant that can potentially stabilize PUFAs in TE oil, but the application to TE oil has not been previously explored. Therefore, this study aimed to evaluate the effect of shrimp shell-derived carotenoprotein on the quality and oxidative stability of TE oil during storage. The proximate composition of tuna eye and shrimp by-products was analyzed during the investigation process. Initial TE oil and TE oil with added carotenoprotein were assessed for free fatty acid content, acid value, peroxide value, p-anisidine value, total oxidation value, and heavy metal content. Carotenoprotein was evaluated for its color and antioxidant activity. The TE oil was combined with 0.4%, 0.6%, and 0.8% (v/v) concentrations of carotenoprotein and examined for stability using the Schaal oven test method at 40°C. The variations in these concentrations were systematically selected to determine potential concentration-dependent effects on TE oil oxidative stability. The results showed that on day 60 of TE oil storage at room temperature, oxidative degradation was significantly influenced by carotenoprotein concentration. Free fatty acids increased to 1.39%, while the values of acid, peroxide, anisidine, and total oxidation identified at the 0.4, 0.6, and 0.8% concentrations were 1.61, 1.50, and 1.24 mg KOH/kg, 18.87, 15.98, and 13.29 meq/kg, 10.80, 11.40, and 9.70 meq/kg, as well as 48.54, 43.36, and 36.28 meq/kg, respectively. Moreover, 0.8% carotenoprotein addition was found to effectively prevent TE oil deterioration compared to the control group.

Unveiling the oxidative stability, phytochemical richness, and nutritional integrity of cold-pressed Linum usitatissimum oil under UV exposure

This study examines the effect of UV irradiation on the oxidation stability of Linum usitatissimum oil, presenting possible changes in the phytochemical profile due to photo-oxidation. GC–MS analysis of the oils identified 11 fatty acid compounds with a high percentage of unsaturated fatty acids, the most important of which is α-linolenic acid (ALA), known as omega-3 (48.88 %), also significant profiles of phytosterol and tcocopherol isomers rich in β-Sitosterol and γ-tocopherols respectively. As well as physicochemical properties such as free fatty acids (FFA %), peroxide value (PV) and iodine value (IV), and nutritional indexes that determine the significant changes observed during the oxidation process, the most important of which is the progressive increase in acidity, peroxide, conjugated dienes and trienes and degrees of unsaturation over 8 h of UV exposure. High levels of carotenoids and phenolic compounds (TPC) protect and enhance oil quality in the face of irradiation, so a significantly small difference is observed between irradiated and non-irradiated oil during photo-oxidation.

Comparative analysis of edible oil quality in fish nugget frying: Vacuum vs. atmospheric conditions

Consumer awareness about safe and nutritional fried food leads to the development of vacuum frying which overcomes major limitations of traditional frying. In this study effect of vacuum (120◦C, 40kPa) and atmospheric frying (180°C) on the fried fish nuggets quality and frying oil was compared. Oils used for frying (soyabean and mustard oil) were repeatedly used for 25 h without any replenishment. Vacuum frying (VF) oils and fish nuggets show a slower degradation of polyunstaurated fatty acids (PUFA), lesser transfatty acid (TFA) formation and a low C18:2/C16:0 ratio as compared to atmospheric frying (AF). Soyabean oil used for vacuum frying fish nuggets show an increase from 2.14 % to 3.11 %, decrease from 45.25 % to 38.29 %, while as AF fish nuggets show an increase from 2.14 % to 5.48 % and decrease from 45.25 % to 22.19 % in TFA content and PUFA content respectively after 25 h of frying. Oil uptake was also found lower (34.89 %) in VF fish nuggets as compared to AF(37.45 %), while as water loss was higher in AF chips than VF nuggets by 1.42-fold after 10 minutes of frying. Sensory analysis revealed that VF fish nuggets show a higher retention of sensory attributes and overall acceptability but they were less crispy then AF fish nuggets. Overall, vacuum frying results in the production of safe and nutritious fried fish nuggets.

Identification of the oxidation and hydrolysis products content influence on the rapeseed oil oxidation induction period

The object of the study is the dependence of the induction period of rapeseed oil on the content of oxidation and hydrolysis products. A feature of the work is determining the approximation dependence of the induction period of accelerated oxidation of refined rapeseed oil on the content of primary oxidation products and free fatty acids. This is useful when predicting the shelf life of refined rapeseed oil. It was determined that both factors negatively affect the oxidation stability of refined rapeseed oil. An increase in the peroxide value decreases the induction period of model oil samples by 32.8512 units for each additional mmol ½ O/kg. In turn, increasing the acid value of oil samples reduces the induction period by 19.8424 units for each additional mg KOH/g. Different oxidation dynamics of model samples of refined rapeseed oil with tocopherol were revealed, depending on the concentration of primary oxidation and hydrolysis products. The obtained data are explained by the fact that the primary lipid oxidation products are unstable and quickly decompose to form free radicals. These radicals initiate further lipid oxidation, resulting in reduced oil quality. In addition, free fatty acids are more reactive than triglycerides and are more easily oxidized. A feature of the obtained results is the possibility of modeling processes that affect the oxidation stability of refined rapeseed oil. From a practical point of view, the research results allow initiating measures to maintain the safety of oil-containing food products based on refined rapeseed oil. An applied aspect of using the scientific results is the possibility of rationalizing the storage conditions of refined rapeseed oil to maximize its shelf life and increase competitiveness

Identification of candidate genes and genomic prediction of soybean fatty acid components in two soybean populations.

Soybean, a source of plant-derived lipids, contains an array of fatty acids essential for health. A comprehensive understanding of the fatty acid profiles in soybean is crucial for enhancing soybean cultivars and augmenting their qualitative attributes. Here, 180 F10 generation recombinant inbred lines (RILs), derived from the cross-breeding of the cultivated soybean variety 'Jidou 12' and the wild soybean 'Y9,' were used as primary experimental subjects. Using inclusive composite interval mapping (ICIM), this study undertook a quantitative trait locus (QTL) analysis on five distinct fatty acid components in the RIL population from 2019 to 2021. Concurrently, a genome-wide association study (GWAS) was conducted on 290 samples from a genetically diverse natural population to scrutinize the five fatty acid components during the same timeframe, thereby aiming to identify loci closely associated with fatty acid profiles. In addition, haplotype analysis and the Kyoto Encyclopedia of Genes and Genomes pathway analysis were performed to predict candidate genes. The QTL analysis elucidated 23 stable QTLs intricately associated with the five fatty acid components, exhibiting phenotypic contribution rates ranging from 2.78% to 25.37%. In addition, GWAS of the natural population unveiled 102 significant loci associated with these fatty acid components. The haplotype analysis of the colocalized loci revealed that Glyma.06G221400 on chromosome 6 exhibited a significant correlation with stearic acid content, with Hap1 showing a markedly elevated stearic acid level compared with Hap2 and Hap3. Similarly, Glyma.12G075100 on chromosome 12 was significantly associated with the contents of oleic, linoleic, and linolenic acids, suggesting its involvement in fatty acid biosynthesis. In the natural population, candidate genes associated with the contents of palmitic and linolenic acids were predominantly from the fatty acid metabolic pathway, indicating their potential role as pivotal genes in the critical steps of fatty acid metabolism. Furthermore, genomic selection (GS) for fatty acid components was conducted using ridge regression best linear unbiased prediction based on both random single nucleotide polymorphisms (SNPs) and SNPs significantly associated with fatty acid components identified by GWAS. GS accuracy was contingent upon the SNP set used. Notably, GS efficiency was enhanced when using SNPs derived from QTL mapping analysis and GWAS compared with random SNPs, and reached a plateau when the number of SNP markers exceeded 3,000. This study thus indicates that Glyma.06G221400 and Glyma.12G075100 are genes integral to the synthesis and regulatory mechanisms of fatty acids. It provides insights into the complex biosynthesis and regulation of fatty acids, with significant implications for the directed improvement of soybean oil quality and the selection of superior soybean varieties. The SNP markers delineated in this study can be instrumental in establishing an efficacious pipeline for marker-assisted selection and GS aimed at improving soybean fatty acid components.

Effect of phosphide additives on the tribological properties of polyethylsiloxane (PES) in Si3N4 and M50 system

PurposeThe incorporation of phosphide additives is regarded as a highly effective strategy for enhancing the lubricative qualities of base oils. This study aims to assess the lubrication behavior and efficacy of various phosphide additives in polyethylsiloxane (PES) through the employment of the Schwingum Reibung Verschleiss test methodology, across a temperature range from ambient to 300°C.Design/methodology/approachPES demonstrated commendable lubrication capabilities within the Si3N4/M50 system, primarily attributable to the Si-O frictional reaction film at the interface. This film undergoes disintegration as the temperature escalates, leading to heightened wear. Moreover, the phosphide additives were found to ameliorate the issues encountered by PES in the Si3N4/M50 system, characterized by numerous boundary lubrication failure instances. A chemical film comprising P-Fe-O was observed to form at the interface; however, at elevated temperatures, disintegration of some phosphide films precipitated lubrication failures, as evidenced by a precipitous rise in the coefficient of friction.FindingsThe results show that a phosphide reactive film can be formed and a reduction in wear rate is achieved, which is reduced by 64.7% from 2.98 (for pure PES at 300°C) to 1.05 × 10–9 μm3/N m (for triphenyl phosphite at 300°C).Originality/valueThe data derived from this investigation offer critical insights for the selection and deployment of phosphide additives within high-temperature lubrication environments pertinent to PES.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0139/

Coupling aquathermolysis of water-heavy oil-methanol catalyzed by o-phenanthroline-Cu(II) complex at low temperature

In this study, a Cu(II) coordinated complex was synthesized using o-phenanthroline and copper chloride. The synthesized complex, serving as a aquathermolysis catalyst, significantly reduces heavy oil viscosity at lower temperatures. Studies indicate that at a reaction temperature of 200 °C, with a catalyst concentration of 0.1% and a reaction duration of 6 h, heavy oil viscosity significantly reduces. Heavy oil viscosity dropped from 392,000 mPa∙s to 63,000 mPa∙s, achieving an 83.93% reduction rate. This catalyst maintains superior catalytic performance at lower temperatures compared to other catalyst types. Using methanol as a hydrogen donor further enhances the catalyst’s effect, increasing the heavy oil viscosity reduction rate from 83.93% to 88.63%. Thermogravimetric, four-component, and elemental analyses reveal that aquathermolysis of heavy oil primarily occurs in its heavier components. Following the aquathermolysis reaction, there is an increase in light components and a decrease in impurity atoms in heavy oil, resulting in improved crude oil quality.

Study of the quality of olive oils imported to Russia

Study of the quality of olive oils imported to Russia

The Effect of Waxes on Rapeseed Oil Quality and Acrylamide Development in Potato Fries during Deep-Frying

This paper analyzed the effects of adding rice bran wax (RW) and beeswax (BW) to rapeseed oil as a deep-frying medium and the quality parameters of potato fries, including acrylamide contamination. It was found that the addition of RW and BW caused an increase in the oil’s acidity. However, oil deterioration based on peroxide values and fatty acid profiles did not differ very much from the oil without waxes. The study showed that the addition of rice bran wax at the level of 2.5 g/L of rapeseed oil was able to significantly decrease oil uptake in potato fries. The addition of waxes did not influence the color parameters in the first frying cycle; however, changes were observed later. The browning index indicated that 10 g of BW per liter may darken fries in comparison to rapeseed oil without additives. It was found that with an increase in wax content in the frying medium, potato fries contained more acrylamide.

Effect of hot-air drying on drying characteristics and quality of tiger nut.

The delayed drying of newly harvested tiger nuts can lead to mold and rancidity. Timely drying is therefore important. However, few studies have analyzed the impact of hot-air drying on the quality of tiger-nut oil and starch, making it essential to establish optimal drying conditions. The results showed that the drying temperature was the most important factor affecting the drying speed, followed by drying airflow rate and loading capacity. A logarithmic model can describe the hot-air drying process of tiger nuts. The oil yield of tiger nut was highest after drying at 60 °C, reaching 22.40%. Meanwhile, the starch extracted from after drying at 60 °C had the highest solubility and expansion rate, 4.77% and 9.74%, respectively. Starch has the highest viscosity after drying at 70 °C, and it forms gel easily after aging. High-quality tiger nuts should be produced under optimal conditions: a hot-air drying temperature of 60 °C, an airflow rate of 1.0 m s-1, and a loading capacity of 100 g. The results of this study have practical implications for the effective drying of tiger nuts. © 2024 Society of Chemical Industry.