Please login first

List of accepted submissions

Show results per page
Find papers
  • Open access
  • 66 Reads
Effect of roasting and marjoram on selected quality parameters of pumpkin seeds and oil.

In many countries, pumpkin seeds are popular snacks eaten raw or roasted. Roasting reduces the moisture content of the seeds and they gain a more fragile and delicate texture as well as a characteristic taste and smell. Pumpkin seeds are used to enrich bread, breakfast cereals and cakes. They are a valuable source of nutrients such as fat, proteins, dietary fiber as well as vitamins and minerals. Pumpkin seeds are used to obtain oil, which, apart from its nutritional and pharmacological properties, is characterised by specific sensory qualities such as colour and taste.

The aim of this study was to investigate the effect of marjoram (Origanum majorana L.) during the roasting of pumpkin seeds on selected properties of both the seeds and the oil obtained.

The material for the study consisted of pumpkin seeds which were roasted at 110°C and 160°C for 10 and 30 minutes without and with dry marjoram in the weight ratio of 10:1 (w/w). After roasting, the water activity and colour of the seeds were determined. In turn, the obtained oil was analysed with regard to the fatty acid composition, peroxide value (PV) and ability to scavenging DPPH radicals.

The study showed that both moisture content and water activity of pumpkin seeds decreased after roasting compared to unroasted seeds, with the values obtained being slightly higher when roasting took place in the presence of marjoram. The presence of marjoram during roasting also caused a decrease in PV values of the oil extracted from pumpkin seeds. Oil samples obtained from pumpkin seeds roasted with marjoram showed a slightly higher ability to scavenging of DPPH radicals compared to oils roasted without the addition of this spice. However, the fatty acid composition did not change significantly. On the other hand, the values of parameter L* were higher for oil samples obtained without the addition of marjoram.

  • Open access
  • 805 Reads
Reusing food waste: Ascorbic acid extraction from orange peel using ultrasound-assisted extraction and natural deep eutectic solvents

The food industry generates a huge amount of waste from the production of food and processed products. There is a need to find a different fate to this waste, use or reuse, to minimize this problem (1). Regarding citrus fruits, the waste of this cultivar has a significant amount of bioactive compounds, like ascorbic acid (AA) (2). The extraction of these compounds can also contribute to environmental pollution due to energy usage and polluting organic solvent by-products (3). Non-conventional extraction techniques and less polluting solvents to recover these compounds from citrus waste would be a better and less pollutant choice. In this study, six hydrophilic Natural Deep Eutectic Solvents (NADES) were prepared to extract AA from orange peel (Navel cultivar). EtOH 50% was used as control. The extraction was done with the aid of Ultrasound-Assisted Extraction (UAE). The UAE parameters: extraction time (5, 10 and, 15 min), intensity (100 W, 200 W and, 400 W), and the magnetic stirring time after UAE (0, 20, 30 and, 45 min) were optimized. The determination of AA was made by HPLC-UV/VIS. Mobile phase A: Milli-Q water/formic acid (95:5) and mobile phase B: acetonitrile/ A (60:40), the injection volume was 1 µl at a flow rate of 0.5 ml/min were used. A standard calibration curve was constructed using the same conditions as the samples (R = 0.9998). The selected optimal conditions were 10 min of extraction, 100 W of intensity (no statistical differences found among intensities), and 45 min of magnetic stirring after treatment. The NADES that presented the highest extraction yield was Malic Acid: Glucose (11.76 mg/100 ml) followed by L-Proline: Malic Acid (7.44 mg/100 ml). NADES provided higher extraction yields than EtOH 50% (5.41 mg/100 ml). In conclusion, two of the studied NADES extracted more AA than EtOH 50% from orange peel.

Acknowledgement: This work was funded by the Spanish Ministry of Science and Innovation - State Bureau of Investigation (PID2019-111331RB-I00/AEI/10.13039/501100011033). Agricultural cooperative Sant Bernat from Carlet, Valencia, for donating the oranges.

1. Krivokapić S, Vlaović M, Damjanović Vratnica B, Perović A, Perović S. Biowaste as a Potential Source of Bioactive Compounds—A Case Study of Raspberry Fruit Pomace. Foods. 2021, 10(4): 706.
2. Montero-Calderon A, Cortes C, Zulueta A, Frigola A, Esteve MJ. Green solvents and Ultrasound-Assisted extraction of bioactive orange (Citrus sinensis) peel compounds. Scientific reports. 2019, 9(1): 1-8.
3. Anticona M, Blesa J, Lopez-Malo D, Frigola A, Esteve MJ. Effects of ultrasound-assisted extraction on physicochemical properties, bioactive compounds, and antioxidant capacity for the valorization of hybrid Mandarin peels. Food Bioscience 2021, 42: 101185.

  • Open access
  • 38 Reads
The thermal characteristics of coffee and cocoa powders prepared by freeze-drying process

The aim of this research was to evaluate thermal properties of cocoa and coffee freeze-dried powders. Medium roasted Arabica beans from Brasil and raw organic cocoa were selected to obtain the following freeze-dried powder variants: 100% coffee, 100% cocoa, 5% cocoa and 95% coffee, 20% cocoa and 80% coffee, 60% cocoa and 40% coffee. In order to characterise thermal behaviour of the freeze-dried powders, modulated differential scanning calorimetry (MDSC) and thermogravimetric analysis (TGA) in oxygen (O2) and nitrogen (N2) atmosphere were performed. Also water activity of prepared powder formulations was measured. It was noticed that freeze-drying process has significant influence on the thermal properties of generated cocoa and coffee lyophilisates. The use of MDSC allowed to determine the midpoint of glass transition temperature (Tg), which reached approximately from 48°C to 60°C. It was also observed that the values of Tg significantly depended on the level of water activity of the powders. TGA revealed that in both atmospheres the thermal decomposition of the freeze-dried powders occured in four stages. For all cases, the highest mass loss (50-60%) was registered in the temperature range (114°C-400°C). Furthermore, the weight loss rate of powders in the N2 atmosphere was slower than in the O2 atmosphere. All of the cocoa and coffee freeze-dried powders were detected with low water activity (below 0,3), what can be attributed to satisfactory microbiological safety of the tested samples. In conclusion, the authors of present study would like to emphasize that coffee powder with 20% cocoa addition could potentially be considered as a promising powder material in terms of thermal stability. This variant of obtained cocoa and coffee lyophilisates was characterized by the lowest water activity and the highest glass transition temperature.

  • Open access
  • 439 Reads
Hydrophobic and hydrophilic Deep Eutectic Solvents to obtain green extracts with biological activity

Now a days food industry is focusing on reutilization of fruit by-products rich in bioactive compounds as carotenoids. These valuable ingredients could be extracted to formulate functional food products. Deep Eutectic Solvents (DES) are a new generation of solvents that comply with the requirements for green extractions and can successfully replace other organic solvents. The aim of the present study was to select the most promising DES for carotenoid extraction from orange peel (OP) and obtain green extracts with biological activity. In order to reduce time and energy the software COSMOtherm was used for the screening of 68 DES to provide the optimal solvent for carotenoid extraction. The results from the software were validated experimentally with the most suitable and unsuitable solvents. OP was obtained from orange fruits (Citrus sinensis, Navel cultivar). Three hydrophobic DES were prepared Menthol: Camphor (Me: Cam), Menthol: Eucalyptol (Me: Eu), Lauric Acid: Octanoic acid (C12:C8) and two hydrophilic Proline: Malic acid (Pro: MA) and Choline chloride: Urea (ChChl: U). Extractions were performed with 1 g of milled OP using different DES (1:10 w/v) for 30 min with 50W of ultrasound power at 45°C. The obtained extracts were characterized by total carotenoid content (TC) determined spectrophotometrically and the biological activity was evaluated in vitro by an antiproliferative assay in tumor cells (HeLa) using MTS reactive. The extracts obtained with hydrophobic DES showed the highest values of total carotenoids, and not significative difference (p>0.05) was found between Me: Cam (163.5±1.1 mg/100gfw), Me: EU (168.7±1.6 mg/100gfw) and C12:C8 (153.1±7.1 mg/100gfw). The in vitro assay showed an antiproliferative effect of Me: Cam extract on tumor HeLa cells with 26.7% of cell viability. The whole formulation (DES and bioactive compound) could be included in final products without any additional purifying steps and can enhanced the bioactivity of food products.

  • Open access
  • 31 Reads
Assessment of the possibility of using differential scanning calorimetry in thermal analysis of fat isolated from whey protein concentrate.

The aim of the study was to assess the possibility of using differential scanning calorimetry (DSC) in thermal analysis of fat isolated from three commercial whey protein concentrates (WPC) containing 80% of whey protein in dry matter. In the first stage of the research, fat was extracted from WPC using the Folch method, and the fat fraction was analyzed for the fatty acid composition by gas chromatography (GC). In the next stage, the thermal properties of the fat were analyzed by DSC by determining the temperature and enthalpy of phase transitions of individual triacylglycerol fractions.

The fatty acid profile of the tested samples was similar with the literature data for cow's milk fat, which is dominated by saturated fatty acids (>60%), and the highest content is shown by palmitic acid (~30%) and oleic acid in the cis conformation (>23%). The fatty acid composition was related to the DSC melting profiles, where endothermic peaks of the low and/or medium and high melting triacylglycerol fractions in the temperature range of –5,5ºC to 35ºC were observed.

  • Open access
  • 25 Reads
The study of apricot kernel oil resistance to oxidation

Apricot kernels, which are a by-product in food processing, still contain 40 to 55 % of oil rich in nutrients and bioactive substances, so they can be successfully used in the production of cooking oils and in medicine. The aim of the study was to evaluate the resistance to oxidation of two commercial cold pressed oils from apricot kernel: M1 and M2. The oxidative stability of tested oils was measured by pressure differential scanning calorimetry (PDSC) under isothermal conditions at five different temperatures: 100, 110, 120, 130, 140 ° C and an oxygen pressure of 1350-1400 kPa. The acid value and the fatty acid composition were also determined in the analyzed oils. Apricot kernel oils contained mainly unsaturated fatty acids in the amount of 91.89 and 88.92 %, of which oleic acid (68.33 and 45.81 %) and linoleic acid (22.07 and 42.01 %) were detected in the highest amount. Saturated fatty acids were mainly represented by palmitic and stearic acids. As expected, the induction time of the tested oils decreased with increase in temperature. The M2 apricot kernel oil with the highest content of polyunsaturated fatty acid was characterized by lower induction time in each temperature range (from 187.20 min. in 100˚C to 6.35 min. in 140˚C) compared to M1 oil, for which induction times ranged from over 700 min. at 100˚C to 31.15 min. at 140˚C. Vegetable oils, due to the high content of unsaturated fatty acids, are less oxidative stable, however, during cold pressing, natural antioxidants are retained, which increases their resistance to oxidation.

  • Open access
  • 37 Reads
Chemopreventive potential of Santolina chamaecyparissus against MNU-induced mammary cancer in female Wistar rats

Breast cancer is the most often diagnosed cancer worldwide, with the greatest fatality rate among women in 2021. Santolina chamaecyparissus L. has been shown to successfully inhibit cancer cells’ proliferation, especially the human breast adenocarcinoma (MCF-7) cell line. This study’s goal was to evaluate the chemopreventive potential of a S. chamaecyparissus aqueous extract (SCE) on -methyl­--nitrosourea (MNU)-induced mammary cancer in female rats.

This study was approved by the ORBEA under reference 834-e-CITAB-2020. Twenty-eight four-week-old female Wistar rats were divided into four groups: Control, MNU, SCE and SCE+MNU. SCE was supplemented in drinking water (120 µg/mL) ad libitum and replaced every 3 days due to the compounds’ stability. A total of nineteen compounds were identified in the extract, being myricetin-O-glucuronide and 1,3-O-dicaffeoylquinic acid the main compounds found. At 50 days of age, the MNU was administered by intraperitoneal route. Humane Endpoints analysis was performed weekly. Induced animals were palpated twice a week. Tumour width (W) and length (L) were weekly measured with a calliper. Tumour volume was also determined [V = (W2 × L) / 2]. After twenty-one weeks, animals were sacrificed by ketamine/xylazine overdose.

Control and SCE animals did not develop any tumours. In MNU group, the first tumour appeared during the ninth week; in SCE+MNU, it only appeared on the sixteenth week. No significant differences were found. However, the tumour incidence in SCE+MNU (28.57%) was lower than in MNU (57.14%). MNU group had a higher mean tumour weight (2.31±1.13) than SCE+MNU group (0.39±0.02) and a larger mean tumour volume (2.02±1.23) than SCE+MNU (0.57±0.15) (p>0.05).

Despite the lack of statistically significant differences between groups, the absence of mortality in SCE+MNU, as well as the lower values in each parameter, suggest that Santolina chamaecyparissus has interesting potential as a chemoprotective agent. Histopathological analysis will help understand this extract’s impact in oncogenesis.

  • Open access
  • 50 Reads
Properties of chemical interesterified mixtures of tomato seed oil with coconut oil.

Interesterification is one of the methods of obtaining structured triacylglycerols, the nutritional and physicochemical properties of which are modified in relation to the naturally occurring ones. An important aspect of this reaction is that it changes the structure and composition of triacylglycerols, but does not affect the natural structure of fatty acids. This is very beneficial as it allows all fatty acids with a health-promoting effect to remain intact. Another advantage of this process is that it does not produce trans fatty acids.

The aim of this work was the analytical evaluation of structured lipids synthesized by chemical interesterification of vegetable oil blends. The mixtures of tomato seed oil and coconut oil at weight ratio 1:3, 1:1 or 3:1 respectively were interesterified for 2 hours at the temperature of 60°C in the presence of chemical catalyst – sodium methoxide. Oxidative stability of interesterified mixtures was determined by using the calorimetric method. The determination of fatty acid composition was carried out by gas chromatographic analysis. The positional distribution of fatty acids in the internal and external positions of triacylglycerols was based on the ability of the pancreatic lipase to selectively hydrolyze ester bonds in the sn-1,3 positions. Peroxide value and acid value were determined using titration method.

Results of research shows that interesterification has influence over reduction of oxidation induction time. The higher the peroxide value, the shorter the oxidation induction time and therefore the lower the oxidative stability of the samples containing more tomato seed oil. The distribution of fatty acids in the mixtures after interesterification was different from that in the analyzed oils. The essential fatty acids from tomato seed oil were incorporated into triacylglycerol structures of coconut oil after modification.

  • Open access
  • 42 Reads
Metabolomic fingerprinting of phenolic compounds in blood serum from rats treated with chestnut shells extract

The intake of dietary phenolic compounds has clearly boosted in the last decades owing to their health-promoting benefits with protective effects against chronic pathologies. Beyond fruits and vegetables, food by-products have also been recognized as promising sources of phenolic compounds. Chestnut shells (CS) are one of these agro-industrial by-products [1, 2]. Although recent studies have proposed the CS valorization as an added-value resource with innovative applications in nutraceutical industry, metabolomic studies should be accomplished to attest the in vivo health effects.

The purpose of this study was to explore the targeted metabolomic profile of phenolic compounds in rat blood serum, following the acute intake of two doses of CS extract (50 and 100 mg/kg b.w.) administered by gastric gavage. The dried and powdered CS were extracted by a green technology, namely Subcritical Water Extraction (SWE), at 220 °C for 30 min [1]. The animal studies were carried out daily for 7 days and blood was collected by cardiac puncture. For metabolomic studies, a LC-ESI-LTQ-Orbitrap-MS analysis was employed in negative mode [3]. Phenolic compounds and metabolites were identified using commercial standards and comparing with databases and literature data.

The results attested the presence of metabolites of phase I (hydrolysis, oxidation, and hydrogenation) and phase II (glucuronidation, methylation and sulfation) reactions. The higher number of metabolites identified were from phenolic acids, including caffeic acid, coumaric acid, ellagic acid, ferulic acid, gallic acid, hydroxybenzoic acid, protocatechuic acid, and syringic acid. Lignans and phase II metabolites were also present, while only one flavanol metabolite was detected. Pyrogallol and catechol metabolites were also noticed. The outcomes enlighten the metabolomic mechanisms in blood serum underlying the acute intake of phenolics-enriched CS extract with proven antioxidant properties by in vitro assays. Notwithstanding, ongoing studies regarding the quantification of phenolic compounds and metabolites are still being attempted.

  • Open access
  • 47 Reads
Bioactive compounds from Andean berry (Vaccinium meridionale Swartz) juice inhibited viability and proliferation from SW480 and SW620 human colon adenocarcinoma cells

Andean berry (Vaccinium meridionale Swartz) or “Mortiño” is a tropical-origin commonly cultivated fruit from the Andean region of South America. The fruit is usually consumed in several preparations such as juice, jams, or fresh fruit, and contains a wide variety of phytochemicals, of which polyphenols account for the most abundant group. Previously, it has been demonstrated the chemopreventive and chemoprotective effects of the juice (ABJ) on colorectal cancer in vitroand in vivo, and its anti-inflammatory properties in vitro as well. However, still more research is needed elucidating molecular mechanisms linked to ABJ. This research aimed to assess the antiproliferative effects of ABJ on two representative human colon adenocarcinoma cells from primary (SW480) and secondary (SW620) tumors. Cells were exposed to several ABJ concentrations (0, 10, 20, and 30 % v/v), and their 24 h-viability was tested (MTT), while cell proliferation was assessed at 24, 48, and 72 h (Sulphorhodamine B). Cloning efficiency was tested using Carnoy’s solution staining. In silico molecular docking was tested using selected ABJ polyphenols (cyanidin-3-glucoside and chlorogenic acid), previously against molecular cancer targets. All treatments reduced cell viability (<80 %, p<0.05), being 30 % v/v were the most effective on SW620 cells (IC50-SW480: 28.19 % v/v ABJ; IC50 SW620: 19.43 % v/v ABJ). A similar trend was shown for the antiproliferative assay, but 20 % v/v ABJ at 24 h was the most antiproliferative treatment for both cell lines. After ABJ treatments, none of SW480 populations were positive for Carnoy’s stain. In silico analysis indicated the highest binding between PON2, Catalase, and Claspin (-9.4 kcal/mol) and cyanidin-3-glucoside, whereas HSP27 and PON2 (-8.7 and -8.3 kcal/mol) were the highest binding affinities for chlorogenic acid. Results indicated that ABJ exerts antiproliferative and inhibits cell viability on SW480 and SW620 cells, which could be attributable to interactions between its main polyphenols and apoptosis-related cancer targets.