Cold Press Extraction Research Articles

Thermal Properties of Seed Cake Biomasses and Their Valorisation by Torrefaction

Seed cakes, by-products from the cold press extraction of vegetable oils, are valuable animal feed supplements due to their high content of proteins, carbohydrates, and minerals. However, the presence of anti-nutrients, as well as the rancidification and development of aflatoxins, can impede their intended use, requiring alternative treatment and valorisation methods. Thermal treatment as a procedure for the conversion of seed cakes from walnuts, hemp, pumpkin, flax, and sunflower into valuable products or energy has been investigated in this paper. Thermogravimetry shows the particular behaviour of seed cakes, with several degradation stages at around 230–280 and 340–390 °C, before and after the typical degradation of cellulose. These are related to the volatilisation of fatty acids, which are either free or bonded as triglycerides, and with the thermal degradation of proteins. Torrefaction at 250 °C produced ~75–82 wt% solids, with high calorific values of 24–26 kJ/g and an energy yield above 90%. The liquid products have a complex composition, with most parts of the compounds partitioning between the aqueous phase (strongly dominant) and the oily one (present in traces). The structural components of seed cakes (hemicelluloses, cellulose, and lignin) produce acetic acid, hydroxy ketones, furans, and phenols. In addition to these, most compounds are nitrogen-containing aromatic compounds from the degradation of protein components, which are highly present in seed cakes.

Assessment of Moringa Seed Oil: Fatty Acid Profile, Oxidative Stability and Antioxidant Activity

Moringa oleiferais called the “miracle tree” and it has more vitamins than even some fruits and vegetables like oranges, carrots etc. Objective: To assess functional groups and compare oxidative stability, fatty acid profile, free fatty acid concentration, and antioxidant activity to commercial vegetable oil. Methods: The moringa seed oil was extracted by cold press extraction and solvent extraction by n-hexane and petroleum ether. Functional group, lipid peroxidation, fatty acid profile, antioxidant activity, and FFAs % were analyzed by FTIR, TBARS, GC-MS, DPPH, and titration respectively. Results: The FTIR spectra of prepared samples showed common functional groups of triglycerides, including a sharp peak at 2984 cm-1 for aliphatic C-H stretching. The maximum TBARS value was 0.234 ± 0.03% in T0 at 30 days of storage, whereas the lowest was 0.167 ± 0.04% in T1 at 0 day. The GC-MS analysis of screw press moringa oil showed a high percentage of monounsaturated fatty acids, with 71.38 ± 0.01% oleic acid, 7.01 ± 0.01% palmitic acid, and 1.92 ± 0.01% linoleic acid. At 15 days of storage, FFAs were 2.28 ± 0.06%, showing low hydrolytic rancidity. The Antioxidant Activity in DPPH analysis was 44.46 ± 0.02%, showing high antioxidant properties. Conclusion: The characteristics of moringa seed oil indicate that it could be an effective edible oil and suitable for the production of food items and other edible products in the food and nutraceutical sectors.

The effect of different hydrodistillation times on the composition and yield of bergamot (Citrus bergamia Risso) peel essential oil and a comparison of the cold‐pressing method

AbstractBergamot (Citrus bergamia Risso) is not consumed as fresh fruit as other members of Citrus. Bergamot essential oil has a unique aroma. Bergamot essential oil is a very valuable product used in perfumery, cosmetics, aromatherapy and food industry due to its beautiful scent and functional properties. As with other Citrus species, the composition of bergamot essential oil can vary according to harvest time, climate and extraction technology. Bergamot essential oil could be obtained by cold press extraction or distillation method. Within the scope of the study, the effect of four different hydrodistillation (HD) times (5, 10, 60 and 120 min) on the composition of bergamot essential oil obtained from Turkish fruits was investigated. In the first 60 min, 96.11% of the total essential oil was obtained. Research findings have shown that the distillation time is quite effective in the composition of bergamot essential oil. Limonene, linalool and linalyl acetate, which are the main components of bergamot essential oil, varied in the range, 42.36%–53.25%, 5.59%–12.18% and 20.84%–26.73%, respectively, with respect to distillation time. In cold press method, bergamot essential oil has lower linalool/linalyl acetate ratio (0.15) compared to HD method and a higher quality essence was obtained.

Probing the physicochemical impact of musk melon seed oil on mayonnaise

Owing to high consumption and industrial preparation of musk melon products, most of its byproducts are wasted without effective utilization. Musk melon agro-based waste material (seeds and peels) is an excellent source of antioxidants and phytochemicals. The purpose of this study was to improve the oxidative stability of mayonnaise by addition of musk melon seed oil. The study was conducted to check the physicochemical effect of musk melon seed oil in mayonnaise. Proximate analysis of seeds (i.e. moisture, crude fat, crude fiber, crude protein, ash, and carbohydrate content) was performed. Oil was extracted by using the cold press extraction method, and this oil was tested for different physicochemical analyses (i.e., saponification value, iodine number, specific gravity, 2,2-diphenyl-1-picrylhydrazyl [DPPH] value, viscosity, free fatty acid, and color). Physicochemical analysis was done during the storage period of 0, 20, 40, and 60 days, prior to performing sensory evaluation of mayonnaise. Data obtained from this analysis were further analyzed using statistical tools. A decreasing trend was observed for DPPH and peroxide values of mayonnaise with progression of days, thus showing that addition of musk melon seed oil decreased the production of free radicals. Hence, adding 40% musk melon seed oil showed the best result for overcoming the oxidation of mayonnaise and minimizing the production of free radicals. The data obtained from the statistical analysis indicated that the aroma and texture values of treatment T5 were maximum, and the color and flavor of treatments T4 and T5 were high. The overall acceptability of treatment T5 was high in which 40% of musk melon seed oil was used to combat the production of free radicals. In brief, waste material could be used for producing different types of products in the industry, rather than discarding the same, as it lessened the cost and provide a good quantity of nutrients.

Valorisation of Raspberry Seeds in Cosmetic Industry-Green Solutions.

The fruit processing industry generates large quantities of by-products well known to be rich in bioactive compounds with numerous nutritional properties and beneficial effects for human health. We developed a strategy to valorise raspberry seeds and obtain valuable ingredients with potential application in cosmetic skincare formulas. Cold press extraction technology was applied to extract oil, and the remaining defatted raspberry seed cake was treated with three proline based deep eutectic solvents (DES) to extract polyphenols. The most potent was proline/citric acid extract, with free and total ellagic acid content (52.4 mg/L and 86.4 mg/L), total phenolic content (TPC, 550.1 mg GAE/L) and radical scavenging activity (RSA, 4742.7 mmol TE/L). After the direct mixing of the extract and after encapsulation with starch as a carrier, the skincare emulsion and microemulsion were characterised by irritation potential (Zein test), transepidermal water loss (TEWL), red blood cell (RBC), and DPPH antioxidant test. The resulting preparations were of improved quality in comparison to the control hand cream, with a low skin irritation effect, lower TEWL, and higher antioxidant potential. This work complies with circular economy principles and green technology standards, and represents the efficient model on how to reuse natural resources through waste minimization.

Aktivitas Tabir Surya Ekstrak Biji Nyamplung (Chalophyllum inophyllum Linn)

This study aims to evaluate the sunscreen activity of nyamplung seed extract resulting from cold press extraction, soxletation with n-hexane solvent, and maceration with alcohol solvent. Apart from that, determining the minimum concentration of using nyamplung seed extract as a sunscreen ingredient. This study was conducted in vitro using UV spectrophotometry with the method developed by Sayre et al., (1979). The results showed that the alcohol extract of nyamplung seeds had the best sunscreen activity with an SPF of 42,499 at a concentration of 1,000 ppm in chloroform:alcohol (1:1) in the ultra protection category. Followed by n-hexane extract and cold pressed extract with SPF 39,951 and 36,349 respectively with the same concentration, solvent, and category. The higher the sample concentration, the lower the percentage of erythema and pigmentation, while the higher the SPF. The lowest concentrations of cold pressed extract, n-hexane, and nyamplung seed alcohol that meet the category of sunscreen with ultra protection were 600, 600, and 400 ppm, respectively.

Concentraciones de nutrientes, digestibilidad in vitro y fermentación ruminal de residuos agroindustriales de Cannabis sativa L. como fuente potencial de forraje para rumiantes

This study aimed to determine the concentration of CP, EE, NSC, fibers, TPC, CT, CBD, THC, in vitro digestibility of dry matter and rumen fermentation parameters of agroindustrial residues of Cannabis sativa L. from two extractive processes of cannabinoids, as a potential source of forage in ruminants feeding. The flower of Cannabis sativa was exposed to cold-press extraction (CPC) and alcoholic extraction (AEC) process; vegetative residues obtained after extractions were compared to raw flower as a control (RFC) using a completely randomized design and Tukey’s test for means comparison. Extractive processes decreased EE, TPC and cannabinoids (CBD and THC). Otherwise, fibers, NSC and digestibility, increased after the extractive processes in CPC and AEC. Similarly, in vitro degradability increased after both extractive processes above 120 % as well as latency period. Additionally, protozoa increased with CPC but no changes were observed in AEC. Likewise, no changes were observed in cellulolytic bacteria in CPC and AEC. However, total bacteria were reduced after both extractions. Moreover, N-ammonia in ruminal fermentations decreased with CPC and AEC whereas total volatile fatty acids increased. In addition, gas production increased above 75 % in CPC and AEC; however, no changes were observed in latency period. Furthermore, methane and CO2 production increased above 80 and 60 %, respectively for CPC and AEC; these augmentations are positively associated with improvements in the ruminal fermentations. In conclusions, the agroindustrial residue of Cannabis sativa L. obtained after the analyzed extractive processes may arise as a potential forage source in ruminants feeding.

Phyto-chemical and bioactive compounds of pumpkin seed oil as affected by different extraction methods

Pumpkin (Cucurbita moschata Duch.) seeds of KH (Kashi Harit) cultivar were chosen for oil extraction by three different methods cold press extraction (CPE), soxhlet extraction (SE) and mechanical shaking extraction (MSE) method. SE method showed highest oil yield (38.03%) followed by CPE (33.25%) and MSE (26.36%) methods. Peroxide and acid value were found to be least in the CPE pumpkin seed oil (PSO) whereas oil stability index was highest in this oil. PSO is a good source of essential fatty acids as it contains significant amount (p < 0.05) of linoleic acid in the range of 44.38–44.47%. PSO also contains major sterols like campesterol, stigmasterol, β-sitosterol, ∆7,22,25-Stigmastratrienol, ∆7,25-Stigmastadienol, ∆5-Avenasterol, etc. CPE oil showed higher values for tocopherols (α, β, γ and δ) (4.01, 0.77, 12.51 and 6.42 mg/100 g, respectively), β-carotene (3.86 mg/kg), TPC (19.26 mg GAE/g), DPPH (46.35%) and squalene (352.63 mg/100 g). Thermal analysis of all oil samples revealed that no endothermic reaction occurred beyond 27.5 °C and remains at liquid state at room temperature. 1HNMR fingerprinting of PSO was carried out to determine the composition of major and minor oil constituents like mono and di-glycerides, aliphatic chains and fatty acids.

Research progress on Walnut oil: Bioactive compounds, health benefits, extraction methods, and medicinal uses.

Walnut oil is extracted from walnut kernels (Juglans regia Linne) or iron walnut kernels (Juhlans sigillata Dode). The percentage of oil in walnuts is 52%-70%. The main constituents in oil are fatty acids, phenols, sterols, squalene, melatonin, vitamins, and minerals. Many extraction methods such as supercritical carbon dioxide extraction, maceration, modified "bligh and dyer extraction," aqueous enzymatic extraction, ultrasonic extraction, soxhlet extraction, and cold-press extraction methods are reported in the literature. Walnut oil showed anti-inflammatory, antitumor, antioxidant, immunomodulatory, neuroprotective, cardioprotective, antidiabetic, and antihyperlipidemic activities. The reported data in the literature suggest that walnut oil has many health benefits. This review summarizes the extraction methods, bioactive constituents, health benefits, and pharmacological actions of walnut oil. PRACTICAL APPLICATIONS: Walnut oil is a natural vegetable oil of significant importance due to their nutritional, and intelligence-boosting benefits. Several factors, including the processing parameters and the phytochemical profile, affect walnut oil products' flavor and color. In addition, storage environment of walnut oil can also affect walnut oil quality. Apart from the predominant ingredient fatty acids, the chemical composition of walnut oil comprises phenols, sterols, squalene, melatonin, vitamins, and minerals. These bioactive compounds are of potential value owing to their health-promoting benefits, including antioxidant, antitumor, and cholesterol-lowering effects. Many chemical constituents were isolated from walnut oil; however, all the compounds are not explored for their possible medicinal value. Thus, clinical studies, exploration of the therapeutic potential and the molecular mechanisms of all the compounds, and development of convenient dosage forms either for therapeutic or functional food purposes are warranted.

Microwave and Roasting Impact on Pumpkin Seed Oil and Its Application in Full-Fat Mayonnaise Formula.

In this study, ‘Béjaoui’ Cucurbita maxima seeds variety were exposed to both microwave and roasting prior to oil cold press extraction. In addition, full-fat mayonnaise formula from untreated and treated pumpkin seed oils was prepared and assessed for their physical stabilities and bioactive properties in 28-day storage at 25 ± 1 °C. A mayonnaise sample prepared with unrefined sunflower seed oil served as a control. The results showed that the microwave pretreatment of seeds greatly enhanced the oxidative stability of the pumpkin seed oil, which increased from 3 h 46 min ± 10 min in the untreated sample to 4 h 32 min ± 14 min in the microwave cold press pumpkin seed oil. The sterol content increased from 4735 ± 236.75 mg/kg oil in the untreated cold press pumpkin seed oil to 5989 ± 299.45 mg/kg oil and 7156 ± 357.8 mg/kg in the microwave cold press pumpkin seed oil and the roasted cold press pumpkin seed oil, respectively. The mayonnaise prepared with microwave cold press pumpkin seed oil exhibited the lowest creaming index and was more stable to droplet growth when compared to the other mayonnaise samples. All mayonnaise samples prepared with pumpkin seed oils exhibited higher total phenolic contents and antioxidant activities during storage when compared to the mayonnaise sample prepared with unrefined sunflower seed oil. Among pumpkin seed oil mayonnaise samples, the highest values were, however, observed in the one prepared with microwave cold press pumpkin seed oil. Thanks to its high nutraceuticals, the latter could be confidently regarded as a natural fat substitute for commercial stable vegetable oils mayonnaise type emulsions.

Comparative Elucidation of Aroma, Key Odorants, and Fatty Acid Profiles of Ivorian Shea Butter Prepared by Three Different Extraction Methods

In the present study, the volatile compounds, key odorants, and fatty acid profiles of Ivorian shea butter produced by cold press extraction (CPE), solvent extraction (SE) and traditional extraction (TE) methods were investigated for the first time. The aroma compounds of shea butter were extracted by the purge and trap method and analyzed by the gas chromatography–mass spectrometry and olfactometry (GC-MS/O) technique. Totals of 51, 49 and 46 aroma compounds were determined in samples from CPE, SE and TE, respectively. It was observed that the volatile compounds of studied material dominated after CPE, in which alcohols (11) were the most abundant chemical group, followed by aldehydes (10) and acids (7). The application of aroma extract dilution analysis (AEDA) resulted in 22, 20, and 16 key odorants in shea butter from CPE, SE and TE, respectively. 3-Hexanol with flavor dilution (FD) factors (2048 in CPS, 1024 in SE and 64 in TE) was found to be the most active aroma compound in all samples. In the fatty acid fraction obtained using the gas chromatography–flame ionization detector (GC-FID) method, 22, 24 and 19 fatty acids were detected in samples after CPE, SE and TE, respectively. The highest number of fatty acids was determined in shea butter using CPE (89.98%). Stearic and oleic acids were the most dominant fatty acids, and all samples of shea butter were rich sources of saturated fatty acids (SFAs). Moreover, the SE samples showed the highest values of DPPH (238.36 µM TEq/kg) and ABTS (534.96 µM TEq/kg), while the CPE samples had the highest total phenolic content (104.64 mg GAE/kg). Principal component analysis (PCA) clearly indicated that the extraction technique could quantitatively or qualitatively induce changes. Thus, this investigation demonstrated that extraction methods have a considerable impact on the quality and chemical composition of the presented material.

Acidic and enzymatic pre-treatment effects on cold-pressed pumpkin, terebinth and flaxseed oils

Oil yield and the properties of oil can be improved with various enzymatic pre-treatments before obtaining oil from oilseeds by cold-press extraction. A commercial mixture of pectolytic enzymes was used in this study. In addition, apple seed meal as a source of β-glucosidase enzyme and citric acid were applied to oilseeds (pumpkin, terebinth and flaxseed) as pre-treatments. The results were evaluated by comparing the effects of the pre-treatments on oil yield and properties. Enzyme preparate could increase the oil yield of pumpkin seeds (~300%) and flaxseed (151%). Significant increases in the phenolic contents of terebinth (from 91.67 to 319.33 mg GAE/kg) and flaxseed oils (from 12.03 to 40.47 mg GAE/kg) were achieved by citric acid and enzymatic pre-treatments. These two pre-treatments were also effective in terms of peroxide formation and oxidative stability in terebinth oil. With the help of the pre-treatments applied to oilseeds it was possible to increase the transition of phenolics from seeds to oil for terebinth oil with increase ratios of 245% for citric acid, 248% for the enzymatic process compared to the control.

Comparison of Four Oil Extraction Methods for Sinami Fruit (Oenocarpus mapora H. Karst): Evaluating Quality, Polyphenol Content and Antioxidant Activity.

The sinami palm (Oenocarpus mapora H. Karst) is a plant from the South American Amazonia that has great potential for industrial applications in the development of functional foods, nutraceuticals and cosmeceuticals. In this manuscript, the physicochemical properties, total polyphenol content and antioxidant activity of sinami oil that was obtained using four extraction systems, namely expeller press extraction (EPE), cold press extraction (CPE), ultrasound-assisted extraction (UAE) and supercritical fluid extraction (SFE), were studied and compared. The oxidative stability (OSI) was statistically non-significant in EPE and SFE. The chromatic properties (CIELab) were influenced by the extraction methods and SFE presented high values of L* and a lower content of plant pigments. Ultrasound-assisted extraction showed a higher content of polyphenols and higher antioxidant activity. Different analyses for the evaluation of the physicochemical properties, the content of total polyphenols and antioxidant activity were used to classify sinami oil according to chemometrics using principal component analysis (PCA). For example, the sinami oil that was obtained using each extraction method was in a different part of the plot. In summary, sinami oil is an excellent resource for plant pigments. Additionally, the information that was obtained on the quality parameters in this study provided a good foundation for further studies on the characterization of major and minor compounds.

Effects of Extraction Processes on the Oxidative Stability, Bioactive Phytochemicals, and Antioxidant Activity of Crude Rice Bran Oil.

This research investigates the effects of different extraction processes on the oil extractability, oxidative stability, bioactive compounds, and antioxidant activity of crude rice bran oil (CRBO). The experimental extraction processes include hexane extraction (HE), cold press extraction (CE), thermally pretreated cold press extraction (CCE), and ultrasound-pretreated cold press extraction (UCE). The results show that thermal cooking and ultrasound pretreatment significantly improve the oil extractability of the cold press extraction process. The oil yields of CE, CCE, and UCE were 14.27, 17.31, and 16.68 g oil/100 g rice bran, respectively. The oxidative stability of CE and CCE oils was higher than HE and UCE oils, as evidenced by the synchrotron-radiation-based Fourier transform infrared (SR-FTIR) absorption peak. The ρ-anisidine values of HE, CE, CCE, and UCE were 0.30, 0.20, 0.91, and 0.31, respectively. Meanwhile, ultrasound pretreatment significantly reduced the bioactive compounds and chemical antioxidant activity of UCE oil. The CE, CCE, and UCE oils (0.1% oil concentration) exhibited higher inhibitory effects against hydrogen-peroxide-induced cellular oxidative stress, compared to HE oil (0.39% oil concentration). Essentially, CCE is operationally and environmentally suitable for improving the oil yield, oxidative stability, bioactive compounds, and antioxidant activities of CRBO.

Essential Oil Coating: Mediterranean Culinary Plants as Grain Protectants against Larvae and Adults of Tribolium castaneum and Trogoderma granarium.

Simple SummaryThe protection of stored agricultural products has been established as a global priority serving both food safety and security. Toxicity and residual issues of synthetic insecticides shifted the research focus towards natural pest control agents. In this context, six edible plants were selected for the conduction of a novel bioprospecting effort aiming to identify potential control agents against the red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) and the khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae). The proposed bioprospecting effort aims to identify the chemodiversity of essential oils (EOs) and exploit the potential of EO-based microemulsion (ME) coating as alternative tools for the management of the tested stored-product insects and the concomitant postharvest losses. Elevated toxicity was recorded against T. castaneum larvae and T. granarium adults. The fact that these EO-based MEs originate from culinary plants renders them safe for human consumption. The present study pioneers the utilization of EO-based MEs as grain protectants in the form of grain coating.Postharvest agricultural losses constitute a major food security risk. In contrast, postharvest protection is strongly linked with food safety. The present study aims to develop novel postharvest protection tools through a bioprospecting protocol utilizing edible essential oils (EOs) as grain coatings. For this purpose, six Mediterranean culinary plants were selected for evaluation. The EOs of juniper, Juniperus phoenicea L. (Pinales: Cupressaceae), marjoram, Origanum majorana L. (Lamiales: Lamiaceae), oregano, Origanum vulgare ssp. hirtum (Link) A.Terracc. (Lamiales: Lamiaceae), bay laurel, Laurus nobilis L. (Laurales: Lauraceae) and tarhan, Echinophora tenuifolia ssp. sibthorpiana (Guss.) Tutin (Apiales: Apiaceae) were retrieved through steam distillation, while lemon, Citrus limon (L.) Osbeck (Sapindales: Rutaceae) EO was retrieved through cold press extraction. All EOs were formulated to microemulsions (MEs) and applied uniformly as a coating on wheat against larvae and adults of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) and Trogoderma granarium Everts (Coleoptera: Dermestidae). All EO-based MEs have been evaluated for the first time as grain coatings. They caused moderate to high mortality to T. castaneum larvae (67.8–93.3% 14 days post-exposure) and T. granarium adults (70.0–87.8% after 7 days of exposure). Citrus limon, O. majorana and E. tenuifolia ssp. sibthorpiana EO-based MEs were the most efficient against T. castaneum larvae, by exhibiting 93.3%, 91.1% and 90.0% mortality 14 days post-exposure, respectively. Origanum majorana, L. nobilis and J. phoenicea EO-based MEs were the most efficient against T. granarium adults, exhibiting 87.8%, 84.4% and 83.3% mortality after 7 days of exposure, respectively. These results indicate that EO-based ME coating is a potent tool against the tested postharvest pests.

Sustainable utilization of cold‐pressed green coffee oil and its by‐products for high‐value materials

In this study, the cold-pressing extraction conditions of regular and defective green coffee beans were compared to obtain green coffee oil (GCO). The total phenolic content (TPC) in GCO, press-cake, and sediment was quantified. GCO was characterized by mass spectrometry and incorporated into carboxymethyl cellulose (CMC) films. Highest TPC was found for cake and sediment from defective beans (55.8 and 41.1 mg of GAE/g dry matter, respectively). Oil yield was increased (5.9%) using the finest particle size (<850 μm). Fatty acids, phenolic compounds, and carboxyatractyloside II were identified in GCO by Direct-Infusion Electrospray Ionization-Mass Spectrometry. Films added with 0.3 ml of GCO and lecithin (0.1 g/1.5 g CMC) exhibited greater strength (38.6 MPa) and flexibility (27.6%). Results are promising for both the production of CMC-GCO films, and high-value antioxidant from GCO and its by-products with a sustainable perspective using defective Arabica beans. Practical applications Green coffee oil (GCO) added to carboxymethyl cellulose films improved mechanical properties in the presence of lecithin. GCO by-products, cake, and sediment from defective beans showed higher content of phenolic compounds than regular beans. From a sustainable and economical perspective, cold-pressed GCO and its residues can be exploited in bio-based materials and high-value antioxidants.

Potential Use of High Pressure Homogenized Hazelnut Beverage for a Functional Yoghurt-Like Product.

Hazelnut beverage is a plant-based beverage produced from hazelnut cake as a by-product obtained after cold press extraction. It has high nutritional value and a significant percentage of consumers show interest in it due to its health benefits. In this study, hazelnut beverage manufactured from by-products of hazelnut oil industry was incorporated into functional yoghurt production. Five formulations (ratio of 1/0, 3/1, 2/1, 1/1, 0/1, v/v, cow milk/hazelnut beverage) of yoghurt-like products were prepared to indicate the storage period of the samples and the analysis performed. For yoghurt production, hazelnut beverage and cows' milk were standardized to 14.5 g 100 g-1 with skimmed milk powder. The use of hazelnut beverage in yoghurt production negatively affected L. bulgaricus counts. Water holding capacity and viscosity values were improved by using hazelnut beverage. Increasing hazelnut beverage concentration led to an increase in the total phenolic compounds and antioxidant activity, malic acid levels and also unsaturated fatty acids, especially oleic and linoleic acid. Using the ratio of 3/1 was found the best in view of appearance, flavor and overall acceptability. Based on the structural, rheological and sensorial properties, this study could guide the dairy industry to use hazelnut beverage obtained from hazelnut cake.

Effect of Different Extraction Methods on the Physicochemical Characteristics of Tetracarpidium Conophorum Müll. Arg. Hutch. and Dalz. Almonds Oil

Tetracarpidum conophorum nut is an oil seed found abundantly in the equatorial forest of Central Africa. The present study was conducted to evaluate the yield and the physicochemical composition oils from T. conophorum kernels extracted by cold and hot pressing. The experiments were carried out with mechanical screw press (type – Komet D85-1G) with a nozzle diameter of 8 mm. The extraction method had an influence on oil yield, with a greater yield for hot pressing at 90 °C (68.86 ± 2.00%) compared to cold pressing at 30°C (64.65±3.82%). The refractive index and the density of oils were not significantly different with respect to the extraction methods. The iodine value varies from 146 for hexane extraction to 170 for cold extraction. For both oils, the acid and peroxide values were in line with Codex standards. The oil extracted with hot press method had higher carotenoid content (32.03 ± 1.86 µg/g). a-tocopherol was greater in the oil obtained through the cold process (16.2 ± 0.20 mg/100 g). The seed oils contained substantial amounts of polyunsaturated fatty acids, including precisely linolenic acid (68% of total fatty acids) and linoleic acid (11% of total fatty acids). Based on its characteristics, oils obtained through cold press extraction was of better quality with respect to preservation of bioactive components. T. conophorum oil may have interesting abilities in nutrition, pharmacology and management of metabolic diseases.

Physico-chemical and antioxidant properties of oils and by-products obtained by cold press-extraction of Tunisian Opuntia spp. seeds

Screw pressed prickly pear seed cakes from four Tunisian varieties were analyzed for their chemical and some functional and antioxidant properties, along with the physico-chemical characteristics of the extracted oils. This extraction yielded 40.14 to 62.95% of oil. Fatty acid (FA) composition revealed domination of linoleic and oleic acids and high content of polyunsaturated FA (∼69-74 %) with presence of ɣ-linolenic, docosadienoic and eicosapentanoic acids. Characterization of the cake seeds showed high amounts of total dietary fibers (82.41-83.54 %), important polyphenol content (∼113-180.81 mg GAE/100g dry matter (DM)) and scavenging activity (IC50: 450-763 μg/mL), good oil holding capacity (4.31g/g for Opuntia Stricta variety), and light beige colors. Amino-acid composition revealed that major components were Glutamic acid, Arginine and Aspartic acid. The data indicate that cold pressed Opuntia seeds could be a source of fiber concentrates which could be used as functional ingredients in the food industry, as well as good quality oils.

Influence of Fresh Palm Fruit Sterilization in the Production of Carotenoid-Rich Virgin Palm Oil.

Palm oil is known to be rich in carotenoids and other phytonutrients. However, the carotenoids and phytonutrients degrade due to high heat sterilization of oil palm fruits. The present study was conducted to produce carotenoid-rich virgin palm oil (VPO) using cold-press extraction. Herein, the influence of sterilization of oil palm fresh fruits in the production of cold-pressed VPO was determined with varying sterilization temperatures, times, and amounts of palm fruits in sterilization. The experimental sterilization conditions were optimized using response surface methodology (RSM) based on the maximum VPO yield and minimum FFAs in cold-pressed VPO. The optimal sterilization experimental conditions of oil palm fruits were determined to be a sterilization temperature of 62 °C, a time of 90 min, and an amount of oil palm fruits of 8 kg. Under these experimental conditions, the maximum cold-pressed VPO yield and the minimal content of free fatty acids (FFAs) obtained were 27.94 wt.% and 1.32 wt.%, respectively. Several analytic methods were employed to determine cold-pressed VPO quality and fatty acids compositions and compared with the crude palm oil. It was found that cold-pressed VPO contains higher carotenoids (708 mg/g) and unsaturated fatty acids compared with the carotenoid (343 mg/g) and fatty acid compositions in CPO. The findings of the present study reveal that the sterilization temperature potentially influences the carotenoid and nutrient contents in VPO; therefore, the optimization of the sterilization conditions is crucial to producing carotenoid- and phytonutrient-rich VPO.