Moringa, Milk Thistle, and Jujube Seed Cold-Pressed Oils: Characteristic Profiles, Thermal Properties, and Oxidative Stability.

Cold-pressed moringa, milk thistle, and jujube seed oils were investigated in terms of their characteristic profiles, thermal properties, and oxidative stability. The findings proved that the extracted oils were characterized by high nutritional values, which encourages their use in various fields. Results showed significant differences between the obtained oils. Overall, jujube seed oil exhibited the best quality parameters, with acidity equal to 0.762 versus 1% for the moringa and milk thistle seed oils. Milk thistle seed oil showed absorbance in the UV-C (100-290 nm), UV-B (290-320 nm), and UV-A (320-400 nm) ranges, while the moringa and jujube seed oils showed absorbance only in the UV-B and UV-A ranges. Concerning bioactive compounds, jujube seed oil presented the highest content of polyphenols, which promoted a good scavenging capacity (90% at 10 µg/mL) compared to the moringa and milk thistle seed oils. Assessing the thermal properties of the obtained oils showed the presence of four groups of triglycerides in the moringa and milk thistle seed oils, and two groups of triglycerides in the jujube seed oil. The thermograms were constant at temperatures above 10 °C for milk thistle seed oil, 15 °C for jujube seed oil, and 30 °C for moringa seed oil, which corresponded to complete liquefaction of the oils. The extinction coefficients K232 and K270, monitored during storage for 60 days at 60 °C, proved that jujube seed oil had the highest polyphenols content and was the most stable against thermal oxidation.

Exploring Bacillus amyloliquefaciens strain OM81 for the production of polyhydroxyalkanoate (PHA) bioplastic using olive mill wastewater.

In this study, bacterial strains isolated from olive oil mill wastewater assigned to Bacillus (n = 4) and Klebsiella (n = 1) genera, were evaluated for their ability to accumulate intracellular PHA granules using Sudan Black staining. A maximum PHA production of 0.14 g/L (i.e., 30.2% wt./wt. in dry biomass) was observed in Bacillus amyloliquefaciens strain OM81 after 72 h of incubation in the presence of 2% glucose (synthetic medium). To reduce bioplastic production costs and recover a polluting product, olive mill wastewater was tested as a carbon source. In this context, the maximum growth (1.45 g/L) was observed in the presence of 50% olive mill wastewater. After extracting the biopolymers with chloroform, quantitative and qualitative analyses were conducted using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). FTIR showed an absorption band at 1730 cm-1 assigned to the elongation of the PHB carbonyl groups. This approach offers a dual benefit of reducing pollution and bioplastic production costs. The Bacillus amyloliquefaciens strain OM81 showed promising results for PHAs production, making it a potential candidate for further investigation. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03808-4.

Microencapsulation via Spray-Drying of Geraniol-Loaded Emulsions Stabilized by Marine Exopolysaccharide for Enhanced Antimicrobial Activity.

The current study investigates the formation of microencapsulated geraniol powder, with the exopolysaccharide EPS-K1B3 produced by Halomonas caseinilytica K1, as wall material, using spray-drying. Evaluation of the antimicrobial activity of the functional emulsions, prepared at either pH 5 or pH 7, was carried out against Gram-positive (Listeria innocua (ATCC 33090)) and Gram-negative (Escherichia coli (DSM682)) bacterial strains. Results showed prolonged antimicrobial efficacy until 30 days of incubation for geraniol microcapsules compared to wet geraniol emulsions, which could confirm the ability of the spray-drying process to protect encapsulated geraniol for a longer period. The highest antimicrobial efficacy of geraniol microcapsules was observed against L. innocua at pH 5. Therefore, the influence of pH on the functional property of geraniol microcapsules could be highlighted beside the targeted bacterial strain.

Recent advances in selective allergies to mammalian milk proteins not associated with Cow's Milk Proteins Allergy.

Cow's milk proteins allergy (CMA) is an atypical immune system response to cow's milk and dairy products. It's one of the most common food allergies in children affecting 8% of the total pediatric population pediatric population. This comprehensive review examines recent studies in CMA, especially regarding mammalian milk allergies such as goat's, sheep's, buffalo's, camel's, mare's and donkey's milk allergies in order to increase awareness of these selective allergies and to reduce allergy risks for those who have them. The consumption of other mammalian milk types is not recommended because of the significant homology between milk proteins from cow, sheep, goat and buffalo resulting in clinical cross-reactivity. However, camel's, mare's or donkey's milk may be tolerated by some allergic patients. Selective mammalian milk allergies are unusual and rare disorders characterized by severe symptoms including angio-oedema, urticaria, respiratory manifestations and anaphylaxis. Based on the reported allergic cases, cheese products including Ricotta, Romano, Pecorino and Mozzarella, are considered as the most common source of allergens especially in goat's, sheep's and buffalo's milk allergies, while the major allergens in donkey's and mare's milk seems to be whey proteins including lysozyme, α-lactalbumin and ß-lactogloblin due to the low casein/whey proteins ratio in equine's milk.

Vinegar production via spontaneous fermentation of different prickly pear fruit matrices: changes in chemical composition and biological activities.

BACKGROUND: This study focused on the valorization of prickly pear (PP) fruit (Opuntia ficus-indica) into vinegar by spontaneous surface fermentation on different starting matrices (with/without the addition of sucrose and with/without PP peel in the raw material). Different parameters were monitored during the fermentation process in terms of their physicochemical and biological properties. RESULTS: Physicochemical and phytochemical analysis revealed significant differences depending on the starting matrix. An increase in total phenolic content (TPC) was observed for the majority of samples when transformed from PP juice into PP vinegar revealing the role of fermentation in enhancing the bioactive compounds content. Better antioxidant and antibacterial activity were detected for vinegar samples compared with the initial starting matrix. Using whole PP fruit resulted in better TPC and antioxidant activity; in contrast, sugar addition had no significant effect on any studied data. Analysis of variance, taking into account the four factors that were studied (matrix, variety, with/without peel, and with/without sugar), demonstrated that only the factor 'presence or absence of the peel' had a significant influence on the TPC values. CONCLUSION: This study demonstrated that both whole PP fruit and PP juice could be used as new raw materials for vinegar production. © 2023 Society of Chemical Industry.

Analysis of Antioxidant and Antiviral Effects of Olive (Olea europaea L.) Leaf Extracts and Pure Compound Using Cancer Cell Model.

The present study aims to assess the antioxidant and antiviral effectiveness of leaf extracts obtained from Olea europaea L. var. sativa and Olea europaea L. var. sylvestris. The total antioxidant activity was determined via both an ammonium phosphomolybdate assay and a nitric oxide radical inhibition assay. Both extracts showed reducing abilities in an in vitro system and in human HeLa cells. Indeed, after oxidative stress induction, we found that exposition to olive leaf extracts protects human HeLa cells from lipid peroxidation and increases the concentration of enzyme antioxidants such as catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase. Additionally, OESA treatment affects viral DNA accumulation more than OESY, probably due to the exclusive oleuropein content. In fact, subtoxic concentrations of oleuropein inhibit HSV-1 replication, stimulating the phosphorylation of PKR, c-FOS, and c-JUN proteins. These results provide new knowledge about the potential health benefits and mechanisms of action of oleuropein and oleuropein-rich extracts.

Optimization of a novel, gluten-free bread's formulation based on chickpea, carob and rice flours using response surface design.

This study aimed to develop nutritious, gluten-free bread with high quality characteristics using a mixture of chickpea, carob and rice flours as substitutes of wheat flour. To optimize the bread formulation, a Box-Behnken experimental design was conducted to evaluate the effect of the corresponding flour blend addition, proofing time and water amount addition on the physicochemical, technological and sensory properties of the obtained formulated bread. The optimized formulation was calculated to contain 70% of mixture flour and 100% of water, with a proofing time of 40 minutes. This formulation produced bread with greater specific volume ( 3.73 ± 0.37 cm3/g) and less baking loss ( 22.98 ± 0.94 % ) than those of control (+) bread ( 2.93 ± 0.21 cm3/g and 31.65 ± 0.72 % , respectively). Findings proved that the mixture flour based on chickpeas, carob and rice represents a good alternative to make gluten-free bread with acceptable baking properties.

Use of front face fluorescence spectroscopy coupled with multivariate data analysis for monitoring biscuits' quality during aging.

In this study, the potentiality of front face fluorescence spectroscopy (FFFS) for the evaluation of the quality of biscuits manufactured with butylated hydroxytoluene and pomegranate peel extract during aging was investigated. By using the principal component analysis, vitamin A and tryptophan spectra allowed a clear discrimination between biscuit samples according to the nature of antioxidants, while fluorescent Maillard reaction products spectra showed clear differentiation between samples according to the storage time. Clear differentiation between biscuits according to the used antioxidants and storage time was achieved by using common components and specific weights analysis. Using partial least-squares regression, excellent prediction of water activity (R 2 = 0.95), and L* values (R 2 = 0.92), and approximate prediction of hardness (R 2 = 0.78), b* values (R 2 = 0.74), and moisture content (R 2 = 0.74) were shown. However, the FFFS failed to predict a* values, primary and secondary oxidation products (R 2 < 0.6).

Cynara cardunculus as a potential source of milk coagulating protease: Effects on physical properties of cow's milk.

In the present research study, Cynara cardunculus (wild cardoon) flowers were blended and extracted using different types of buffers (phosphate buffer; citrate buffer and distilled water) for different maceration times. The most reliable, quick and efficient buffer was found to be phosphate (pH = 6.5) with a 6-h maceration time, which was used throughout this study. C. cardunculus extract (CE) was found to have high clotting and proteolytic activities. The extracted enzyme was found to be very stable against a wide range of pH values as well as of temperature. The formation of milk gels prepared in the presence of CE with different types of milk was evaluated using dynamic rheology and Turbiscan. The evolution of both elastic (G') and viscous (G″) moduli was monitored with time. The values of the whole milk enriched with milk powder gels were higher. Coagulum stability was evaluated using Turbiscan. The textural properties and the curd-firming rate of coagulum were also determined. In conclusion, the prepared CE could be an efficient milk-clotting agent in the production of dairy products.

Date, Apple, and Pear By-Products as Functional Ingredients in Pasta: Cooking Quality Attributes and Physicochemical, Rheological, and Sensorial Properties.

This study aims to evaluate the impact of incorporating pear, date, and apple by-products on pasta properties. Pasta properties including cooking quality, texture, color, rheology, thermal gelling, and microstructural characteristics were evaluated. Common wheat flour was substituted by 0, 2.5, 5, 7, and 10 g/100 g of by-products. To choose the best-suited substitute of flour for the preparation of pasta, the sensorial properties of pasta were investigated. Interrelationships between all the physicochemical parameters were investigated using multiple factor analysis. We also studied the impact of storage (7, 15, and 30 days) on the physicochemical proprieties of pasta. The results revealed that the chemical composition of pasta elaborated with by-products was characterized by higher energy (~386 Kcal) and fiber content (~13%) than the control pasta. Generally, materials added to the durum wheat pasta reduce optimum cooking time, adhesiveness, and extensibility, and enhance the swelling index, cooking loss, cooking water absorption, water activity, firmness, and tenacity of pasta. Cooked pasta samples were significantly (p < 0.05) darker (L*) and greener (-a*) than the control pasta. Increasing the rate of by-products from 2.5% to 10% principally altered the texture and structure of pasta. Scanning electron microscopy analysis showed that the inclusion of by-products into pasta leads to a disruption of the protein matrix. A practical formulation (2.5% of by-products) can be selected, since a significant difference was detected between overall acceptability scores. Grouping the variables in the principal component analysis plot showed that pasta samples can be divided into three groups. Each group was correlated by a specific variable. A significant modification of the physical parameters of pasta was observed after 30 days of storage.

Characterization of nettle leaves (Urtica dioica) as a novel source of protease for clotting dromedary milk by non-destructive methods.

This study investigates the valorization of the nettle leaves (Urtica dioica) as a novel source of a protease for clotting dromedary milk. The aim of this work is to study the effect of extracting pH on the enzymatic activity of nettle leaves extracts. The extraction was achieved in phosphate citrate buffer at different pH values (from 3 to 6.5) and the obtained extracts were used to coagulate dromedary milk. The characterization of the obtained extracts was carried out using non-destructive methods namely FT-MIR, fluorescence spectroscopy and turbiscan instrument. The extract prepared at pH = 4 had the highest proteolytic activity. The fluorescence and turbiscan measurements revealed a substantial effect of the pH value on chlorophyll residues extraction and stability, respectively. At an acidic environment (pH range of 3 - 4), the enzymatic extracts were unstable (with turbiscan stability index (TSI) values ~ 20), while at a nearly neutral pH value (pH range of 5 - 6.5), they were found to be more stable as indicated by the low TSI values ~ 1. The maximum milk-clotting activity (MCA) (0.021 U/mL) was obtained for the extracts prepared at pH = 4.

Sustainable use of agro-industrial wastes as potential feedstocks for exopolysaccharide production by selected Halomonas strains.

Large quantities of waste biomass are generated annually worldwide by many industries and are vastly underutilized. However, these wastes contain sugars and other dissolved organic matter and therefore can be exploited to produce microbial biopolymers. In this study, four selected Halomonas strains, namely, Halomonas caseinilytica K1, Halomonas elongata K4, Halomonas smyrnensis S3, and Halomonas halophila S4, were investigated for the production of exopolysaccharides (EPS) using low-cost agro-industrial wastes as the sole carbon source: cheese whey, grape pomace, and glycerol. Interestingly, both yield and monosaccharide composition of EPS were affected by the carbon source. Glucose, mannose, galactose, and rhamnose were the predominant monomers, but their relative molar ratio was different. Similarly, the average molecular weight of the synthesized EPS was affected, ranging from 54.5 to 4480 kDa. The highest EPS concentration (446 mg/L) was obtained for H. caseinilytica K1 grown on cheese whey that produced an EPS composed mostly of galactose, rhamnose, glucose, and mannose, with lower contents of galacturonic acid, ribose, and arabinose and with a molecular weight of 54.5 kDa. Henceforth, the ability of Halomonas strains to use cost-effective substrates, especially cheese whey, is a promising approach for the production of EPS with distinct physicochemical properties suitable for various applications.

In Vitro Anti-Epstein Barr Virus Activity of Olea europaea L. Leaf Extracts.

Olea europaea L. var. sativa (OESA) preparations are widely used in traditional medicine in the Mediterranean region to prevent and treat different diseases. In this research, olive extracts derived from the leaves of the OESA tree have been screened for antioxidant activity by two methods: the DPPH free radical scavenging assay (DPPH) and the Ferric reducing antioxidant power (FRAP) assay. The DPPH assay showed that OESA possesses a stronger antioxidant activity (84%) at 1 mg/mL while the FRAP method showed a strong metal ion chelating activity (90%) at 1 mg/mL. The low IC50 values, obtained by two different methods, implies that OESA has a noticeable effect on scavenging free radicals comparable to standards. During EBV infection, the free radicals increased triggering lipid oxidation. Therefore, the monitoring of the secondary lipid peroxidation products was done by measuring malonaldehyde (MDA) and conjugated dienes (DC). The simultaneous treatment of Raji cells with OESA and TPA, as an inductorof the lytic cycle, generated a significant decrease in MDA levels and DC (p < 0.05). Besides, Raji cells simultaneously exposed to TPA and OESA exhibited a percentage of EBV-positive fluorescence cells lower than TPA treated cells (**** p < 0.0001). This suggests that OESA treatment has a protective effect against EBV lytic cycle induction.

Development and characterization of chitosan films carrying Artemisia campestris antioxidants for potential use as active food packaging materials.

Active food packaging films based on chitosan and enriched with Artemisia campestris hydroalcoholic extract (ACHE), aqueous extract (ACAE) and essential oil (ACEO) were developed. The effects of incorporating A. campestris were investigated on the physical, mechanical, thermal and antioxidant characteristics of the films. The structural properties of the films were evaluated using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that adding ACHE and ACEO improved the water resistance of chitosan films. The FTIR spectroscopy analysis revealed covalent interaction and hydrogen bonding between chitosan and ACHE. The XRD and SEM analyses indicated that interactions occurred between the film matrix and A. campestris active compounds, which could be reflected by the physical and mechanical properties of composite films. Incorporating ACHE and ACAE in the chitosan matrix decreased the tensile strength. The film extensibility was reduced when ACHE and ACEO were added. All films exhibited great thermal stability as the degradation occurred above 300 °C. The addition of A. campestris active compounds, particularly extracts, to chitosan films notably increased the antioxidant and UV-Vis barrier properties. Chitosan films enriched with the A. campestris antioxidant compounds could be applied as food packaging alternatives.

Effect of brine concentration on physico-chemical characteristics, texture, rheological properties and proteolysis level of cheeses produced by an optimized wild cardoon rennet.

The main objective of this study was to test the efficiency of a wild cardoon (Cynara cardunculus L.) rennet, previously optimized by response surface methodology, in cheese making process; then to select the best brine concentration, leading to excellent cheese quality. Results showed that the optimized C. cardunculus rennet and chymosin produced curds with similar properties (yield, colour, texture, viscoelasticity), suggesting that this coagulant could replace successfully calf rennet. After brining at different salt concentrations (5, 7, 10 and 15%), we concluded that the use of 15% of salt in brine was an efficient way to reduce considerably the proteolysis level in C. cardunculus cheeses, stored for 28 d at 4 °C. At this salt level, the highest hardness, gumminess, viscoelasticity and yield of soft cheeses were also recorded. In conclusion, the satisfactory findings could open new opportunities to produce industrially the optimized C. cardunculus rennet and its cheeses in the Mediterranean area.

Chemical, physical and sensory characteristics of biscuits enriched with jujube (Zizyphus lotus L.) flour and fiber concentrate.

The present study was undertaken to evaluate the effect of partial wheat flour substitution by jujube flour (JF) or jujube fiber concentrate (JFC) (0-15%) on chemical, physical and sensory quality of biscuits. JFC extracted from jujube pulp was characterized by high fiber (89.61% DM) and phenolic (6.8 mg GAE/g) contents and showed good functional properties. Textural characteristics of biscuit doughs weren't negatively affected by wheat flour substitution. The enriched biscuits with JF or JFC showed improved nutritional quality proved by an increase in dietary fiber, ash and total phenolic contents. No variations were observed for the weight, thickness, diameter and spread ratio of enriched biscuits as compared with the control. Biscuit hardness increased, but L* values decreased significantly with the substitution level. Regardless the JF level, sensory quality of biscuits was acceptable. For JFC, a maximum of 10% can be incorporated to obtain desirable biscuits quality.

Rheological and emulsifying properties of an exopolysaccharide produced by potential probiotic Leuconostoc citreum-BMS strain.

EPS-BMS, is to our knowledge, the first high molecular weight exopolysaccharide from potential probiotic Leuconostoc citreum-BMS strain that consists on a mixture of α-(1,6)-dextran branched at the third position and ß-(2,6)-levan. This sample exhibited interesting rheological and emulsifying properties under different conditions. Steady shear experiments proved that EPS-BMS had a pseudoplastic behavior without thixotropic properties. Interestingly, pseudoplasticity was maintained even under stress conditions of temperature, pH and salts, which could provide some sensory properties for food products such as mouth feel. Dynamic oscillatory measurements reflected a liquid-like behavior of the sample regardless of the studied EPS concentration, pH, temperature and ionic force. Results related to the emulsifying as well as interfacial properties showed that EPS-BMS had great potential to be applied as emulsifier and/or emulsion stabilizer in both neutral and acidic conditions. Based on the properties reported in this work, EPS-BMS could be potentially applied in the food industry.

Effect of heat treatments on foaming and physico-chemical properties of bovine and camel sodium caseinate.

The objective of this study was to examine the foaming properties of sodium caseinates (Na-cas) extracted from bovine and camel fresh milks after heating at 70, 80, 90 and 100°C for 30 min at laboratory scale. Experimental results indicated that greater foam was obtained with camel Na-cas than with bovine Na-cas at all heating temperatures due to the higher ß-casein content in camel caseins (~53.4% of total proteins, RP-HPLC results). Increasing heat-treatment temperature to 100°C significantly enhanced the foaming properties by raising surface hydrophobicity and decreasing electronegative charge as well as interfacial tension values upon heating. This study concluded that camel Na-cas has important foaming properties in agricultural and food industries.

Optimization of gluten-free sponge cake fortified with whey protein concentrate using mixture design methodology.

This study aimed to optimize mixtures of whey protein concentrate (WPC) and two flours of rice and maize flours for the production of gluten-free sponge cakes. This was obtained by using mixture design methodology. WPC incorporation had positive effects on specific volume and baking loss of cakes, whilst, their incorporation increased their hardness. Considering all cakes properties, two formulas F1 (78.5% Maize, 15% Rice and 6.5% WPC) and F2 (82.4% Maize, 12% Rice and 5.6% WPC) were optimized using a mixture design. The microstructure F1 was more organized and very well structured with smaller aggregates. According to the organoleptic evaluation, F1 was also most appreciated by the tasting panel. The findings of the present study indicated that maize and rice flours, and WPC could be used as a substitute for wheat flour in producing sponge cakes of high quality.

Physicochemical, techno-functional, and fat melting properties of spray-dried camel and bovine milk powders.

In this study, three skimmed and one whole-fat spray-dried camel milk powders were produced and their characteristics were compared to those of bovine milk powders. The physicochemical analysis of the produced powders indicated that camel milk powders (whether skimmed or not) presented higher ash and whey protein contents as compared to those of bovine milk powders. Our results indicated that the investigated camel and bovine milk powders exhibited a high solubility index (>99%) with poor dispersibility and wettability indexes due to their small particles size (d50 ≤ 12 µm) and their narrow size distribution (span ≤ 2). In addition, although camel and bovine milk powders presented the same total fat content, lower free fat content was measured for camel milk powders. Besides, the whey protein nitrogen index and the SDS-PAGE electrophoresis underlined that camel and bovine milk proteins remained intact after drying with low denaturation extent. It is worth noticed that camel milk proteins were less denaturized due to the absence of the heat-sensitive ß-lactoglobulin in camel milk. Moreover, the low denaturation extent participated in the enhancing of the foaming capacity and stability of camel and bovine milk powders. Finally, the calorimetric analysis showed that higher fat melting temperatures were recorded in whole-fat camel milk powder and in their anhydrous form as compared to those of bovine milk. PRACTICAL APPLICATION: Camel milk powder is an emerging non-bovine dairy product. Understanding its rehydration ability and evaluating the impact of spray drying on its protein quality are promising approaches to obtain high-quality camel milk powder with high reconstitution ability. Findings of this study indicated that spray drying is a suitable technique to produce highly soluble camel milk powders with low denaturation extent. These results will benefit the research and development department of food industry (especially those producing camel milk powder) as well as the direct consumers.