The Gelatin-Coated Nanostructured Lipid Carrier (NLC) Containing Salvia officinalis Extract: Optimization by Combined D-Optimal Design and Its Application to Improve the Quality Parameters of Beef Burger.

The current study aims to synthesize the gelatin-coated nanostructured lipid carrier (NLC) to encapsulate sage extract and use this nanoparticle to increase the quality parameters of beef burger samples. NLCs were prepared by formulation of gelatin (as surfactant and coating biopolymer), tallow oil (as solid lipid), rosemary essential oil (as liquid lipid), sage extract (as active material or encapsulant), polyglycerol ester and Tween 80 (as low-molecular emulsifier) through the high-shear homogenization-sonication method. The effects of gelatin concentrations and the solid/liquid ratio on the particle size, polydispersity index (PDI), and encapsulation efficiency (EE%) of sage extract-loaded NLCs were quantitatively investigated and optimized using a combined D-optimal design. Design expert software suggested the optimum formulation with a gelatin concentration of 0.1 g/g suspension and solid/liquid lipid ratio of 60/40 with a particle size of 100.4 nm, PDI of 0.36, and EE% 80%. The morphology, interactions, thermal properties, and crystallinity of obtained NLC formulations were investigated by TEM, FTIR, DSC, and XRD techniques. The optimum sage extract-loaded/gelatin-coated NLC showed significantly higher antioxidant activity than free extract after 30 days of storage. It also indicated a higher inhibitory effect against E. coli and P. aeruginosa than free form in MIC and MBC tests. The optimum sage extract-loaded/gelatin-coated NLC, more than free extract, increased the oxidation stability of the treated beef burger samples during 90 days of storage at 4 and -18 °C (verified by thiobarbituric acid and peroxide values tests). Incorporation of the optimum NLC to beef burgers also effectively decreased total counts of mesophilic bacteria, psychotropic bacteria, S. aureus, coliform, E. coli, molds, and yeasts of treated beef burger samples during 0, 3, and 7 days of storage in comparison to the control sample. These results suggested that the obtained sage extract-loaded NLC can be an effective preservative to extend the shelf life of beef burgers.

New Healthy Low-Sugar and Carotenoid-Enriched/High-Antioxidant Beverage: Study of Optimization and Physicochemical Properties.

Lutein is a prominent biologically active carotenoid pigment with a polyene skeleton that has great benefits for human health. The study examined the synergistic effects of potentially functional components, including lutein carotenoid (LC), Mentha × Piperita extract (MPE), and Citrus × aurantifolia essential oil (CAEO), all three as bioactive components and antioxidants (AOs), on the physicochemical characteristics of a new low-sugar and carotenoid-enriched high-antioxidant beverage. Sucralose was utilized as a non-nutritive sweetener. Polynomial equations obtained by combined design methodology (CDM) were fitted to the experimental data of total phenolic and flavonoid contents (TPC and TFC, respectively) and antioxidant potential of the beverages using multiple regression analysis with R2 (determination coefficient) values of 0.87, 0.89, and 0.97, respectively. Estimated response values for the TPC, TFC, and antioxidant potential (determined as 2, 2-diphenyl-1-picrylhydrazyl radical (DPPH•) scavenging activity) of the optimum beverage formulation were 41.90 mg gallic acid equivalent (GAE) per L-1, 27.51 mg quercetin equivalent (QE) per L-1, and 34.06%, respectively, with a desirability value of 0.74. The potentially functional components had a synergistic effect on the antioxidant potential. This healthy beverage can have the potential to enhance health benefits and may have therapeutic potential for diabetic patients.

Physico-Mechanical Optimization and Antimicrobial Properties of the Bionanocomposite Films Containing Gallic Acid and Zinc Oxide Nanoparticles.

The mechanical and physical properties of the bionanocomposite films based on κ-carrageenan (KC)-gelatin (Ge) containing zinc oxide nanoparticles (ZnONPs) and gallic acid (GA) were optimized using the response surface method, and the optimum amounts of 11.19 wt% GA and 1.20 wt% ZnONPs were obtained. The results of XRD, SEM, and FT-IR tests showed the uniform distribution of the ZnONPs and GA in the film microstructure, and suitable interactions between biopolymers and these additives, which led to increasing the structural cohesion of the biopolymer matrix and improving the physical and mechanical properties of the KC-Ge-based bionanocomposite. In the films containing gallic acid and ZnONPs, an antimicrobial effect was not observed against E. coli; however, the GA-loaded and optimum films show an antimicrobial effect against S. aureus. The optimum film showed a higher inhibition effect against S. aureus compared to the ampicillin- and gentamicin-loaded discs.

Development of a Novel Low-Calorie Lime Juice-Based Prebiotic Beverage Using a Combined Design Optimization Methodology.

A novel lime-juice based low-calorie functional beverage was developed by using D-optimal combined design optimization. For the preparation of the beverage, the following functional ingredients were used: lime juice, lime peel essential oil (LEO) as a flavoring agent and bioactive component, sucralose as a low-calorie sweetener, an inulin/polydextrose (I/P) mixture as prebiotic fibers, pectin as a thickening agent and soluble dietary fiber, lutein as a carotenoid colorant and antioxidant, and peppermint extract (ME) as a flavoring agent and bioactive component. A combined design consisting of one mixture factor (LEO/ME ratio), one numeric factor (lutein concentration), and one categoric factor (presence or absence of prebiotics) was used for optimizing the functional beverage based on the sensory quality. Regression models were adequately fitted to the data of sensory acceptance with a determination coefficient >90%. The sample containing a mixture of prebiotics, 2:3 (v/v) ratio of LEO: ME, and 3 mg/100 mL lutein was selected as the best formulation among the six optimal beverages which was suggested by Design-Expert software. This final optimum sample showed the highest total phenolic (44.22 mg gallic acid equivalents/L) and flavonoid (25.49 mg quercetin equivalents/L) contents, and its antioxidant activity (as 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) scavenging) was 38.30%. The newly designed beverage has the potential to promote health benefits and in therapeutic applications.

Cauliflower by-products as functional ingredient in bakery foods: Fortification of pizza with glucosinolates, carotenoids and phytosterols.

Industrial cauliflower by-products still represent a no-value food waste, even though they are rich in bioactive compounds. With the aim of valorizing them, optimized special flours rich in glucobrassicin, lutein, ß-carotene, and ß-sitosterol obtained from leaves, orange and violet stalks were used at 10 and 30% w/w in the formulation of functional leavened bakery. For the first time, the effect of bioactive compounds enrichment in pizza products as well as the rheological properties were evaluated. As results, pizza making process affected the recovery of the bioactive compounds. The recovery of glucobrassicin and carotenoids in pizza depended on the aerial part of cauliflower. Pizza with violet stalks was the richest in glucobrassicin, providing 8.4 mg per portion (200 g). Pizza with leaves showed the highest carotenoid content with a 90% of recovery rate while pizza with orange stalks provided up to 5.8% of the phytosterols health claim requirement. All 10% enriched pizzas revealed viscoelastic and springiness properties similar to the control, contrary to 30% fortification level. Therefore, the use of 10% special flour in pizza should meet both technological industrial processing and consumer acceptance. Orange stalks are the most promising ingredients for high levels of fortification in pizzas.

Application of mixture design methodology for development of high antioxidant fruity functional beverage.

Three red color fruit juice (pomegranate (PJ), barberry (BJ), and grape juice (GJ)) and three plant extracts (cardamom essential oil (CE), ginger extract (GE), and hibiscus solution (HS)) were used for the development of different functional beverages. Organoleptic analysis was done to detect the most acceptable fruit juice blend. The physicochemical properties of the samples including total phenols, 1,1-diphenyl-2-picrylhydrazyl (DPPH) inhibition percent, anthocyanin, flavonoid, and vitamin C content of optimum fruit juice blend (60% PJ/20% BJ/20% GJ) were 121.57 µg gallic acid equivalent (GAE)/ml, 80.28%, 4.03 mg/L, 64.87 mg/100 ml, and 51.10 mg/100 ml, respectively. To determine the optimum level of extracts and essential oil (GE, CE, and HS) in fruit juice blends, the mixture design method was used and 14 runs (formulations) were obtained. In all formulations, samples containing HS had the highest content of antioxidant and active components and the statistical analysis indicated that the sample containing 0.5 CE/0.5 GE/1 HS (ml/100 ml) had the optimum content of antioxidant components. Thus, the results of this study introduce a functional drink possessing high polyphenols, antioxidants, anthocyanin, and vitamin C content.

Polysaccharide extracted from Althaea officinalis L. root: New studies of structural, rheological and antioxidant properties.

A water-soluble acidic polysaccharide (AOP-2) from Althaea officinalis L. root was isolated by water extraction and purified by ion exchange chromatography (Cellulose DEAE-52) and gel filtration (Sephadex G-200). The structure characteristics of AOP-2 was determined by gel permeation chromatography (GPC), high performance liquid chromatography (HPLC), fourier transform infrared (FT-IR), nuclear magnetic resonance (NMR) spectrum and gas chromatography-mass spectrometry (GC_MS). The results indicated that the AOP-2 was an acidic hetropolysaccharide with the molecular weight of 639.27 kDa. The AOP-2 composed of 51% galacturonic acid, 32.56% rhamnose, 12.73% glucose and 3.71% galactose. It could be found that the main backbone chain of AOP-2 consisted of →3)-α-D-GalpA-(1→, →3)-α-D-Rhap-(1→ and→3,4)-ß-D-Galp-(1→ with branches of →4)-α-D-Rhap-(1→, →4)-α-D-Glcp-(1→ and α-D-Rhap-(1 â†’ . Thermal analysis revealed that the AOP-2 had high thermal stability and according to the results obtained from XRD analysis, it had a semi-crystalline structure. The results of Steady-shear flow and dynamical viscoelasticity showed that AOP-2 solutions exhibited shear-thinning behavior with high viscosity and a weak gel-like behavior at concentrations above 1% in linear viscoelastic region. In addition, it showed relatively high antioxidant property.

The effect of Macro and Nano-emulsions of cinnamon essential oil on the properties of edible active films.

The effect of Nano-emulsion (NE) and Macro-emulsion (ME) of cinnamon essential oil (CEO) on the properties of carboxymethyl cellulose (CMC)-based films was investigated. MEs (diameters of 242-362 nm) and NEs (diameters of 59-80 nm) of CEO were produced through Ultra-Turrax and Ultrasonication, respectively. The scanning electron microscopy (SEM) and atomic force microscopy (AFM) images showed different morphologies in the films containing ME and NE, also a denser and more uniform microstructure was observed in the NE films in comparison with the ME ones. The higher stability of NE in the CMC matrix, increased the thickness of the resulted films. The water vapor permeability (WVP) was increased from 2.59 × 10-9 g/ms Pa in the control film to 4.43 × 10-9 g/m s Pa in the ME film, and decreased to 1.80 × 10-9 g/ms Pa in the NE film. Adding CEO led to more flexible films with enhanced strain at break (SAB) from 53.56% in the control film to 80% and 94.77% in the ME and NE films, respectively. The antifungal indices against A. niger and M. racemous were 14.16% and 20.82% in the ME films, and were improved to 18.81% and 25% in the NE ones.

The emulsifying and foaming properties of Amuniacum gum (Dorema ammoniacum) in comparison with gum Arabic.

In this study, the emulsifying and foaming properties of a novel exudate gum from Dorema ammoniacum (AMG) were assessed in comparison with the well-known gum Arabic from Acacia tree (GAC). The sunflower oil-based emulsion (10% v/v) containing various concentrations (5%-15% w/v) of AMG and GAC was prepared. At all concentrations, AMG showed higher surface and interface activity than GAC. Increasing in AMG and GAC concentrations caused to increase and decrease in Z average, respectively. Overall, the GAC-stabilized emulsion showed lower Z average and PDI value than the AMG-stabilized emulsion during storage time. The sample containing AMG showed higher emulsion capacity and lower emulsion stability in comparison with the one containing GAC at all concentrations. The storage stability decreased and increased with increasing in AMG and GAC concentrations, respectively. After two-week storage, the emulsions containing 10 and 15% AMG showed higher phase separation than those containing GAC; however, this was opposite about sample containing 5% AMG. At thermal, centrifuge, and freezing conditions, the emulsion containing 5% AMG indicated significantly higher stability than GAC samples; however, at higher concentration, opposite effect could be observed. The foaming capacity of the samples containing AMG increased from 81% to 93% by increasing gum concentration from 5% to 15%. The solutions containing AMG showed higher foam capacity than control samples (without gum) and those containing GAC at all concentrations. Increasing in AMG and GAC concentrations slightly improved foam stability, and the highest value (92%) belonged to 15% AMG solution.

Sugar conversion induced by the application of heat to grape must.

Two lots of the grape Trebbiano cultivar were harvested from the same vineyard 15 days apart, and their musts were cooked in an open stainless steel pan directly heated by fire; the kinetics of formation or disappearance of key constituents was then monitored for at least 16 h. From an engineering standpoint, the vessel behaved like a nonisothermal batch reactor in which the volume of the grape must necessarily decreased while its composition changed profoundly as a result of chemical reactions. Brix, total titratable acids, acetic acid, malic acid, lactic acid (d and l), pH, water activity, 5-HMF, and phenolic and radical-scavenging compounds were proposed as markers of the extent of cooking for which water vaporization and sugar degradation were identified as the two main driving factors. Acid-catalyzed dehydration was hypothesized as the predominant mechanism for sugar degradation, assuming a direct role of water vaporization; however, contributions of Maillard degradation pathways and other parallel reversible reactions were also hypothesized. Fractional conversion of 5-HMF and radical-scavenging compounds were proposed as quantitative markers for the extent of sugar degradation at, respectively, the early and advanced stages of cooking. Selectivity indices were also proposed as a performance criterion to design cooking processes in relation to sugar degradation.

Evaluating in vitro antimicrobial activity of thymol toward hygiene-indicating and pathogenic bacteria.

Results of a study of the kinetics of bacterial inhibition by thymol in order to develop appropriate applications for the compound in food systems are presented. A modeling-based approach was used to provide a quantitative description of the antimicrobial activity of thymol toward some foodborne pathogens and hygiene-indicating bacteria, which could be postprocessing contaminants of ready-to-eat meat products. The effect of the active compound on the bacterial growth was assessed from growth kinetics curves and dose-response profiles in a wide range of thymol concentrations, i.e., from 50 to 1,000 ppm. Inhibitory data were produced using a macrodilution methodology based on a turbidimetric technique. Microbial response was discussed in terms of Gompertz's parameters as well as in terms of the active concentration of thymol affecting the growth status of microbial suspension (noninhibitory concentration and MIC). Results suggested that thymol can be successfully used as an alternative antimicrobial to increase the lag time as well as to decrease the maximum value of the growth index as reached in the stationary phase of the growth cycle for all investigated bacteria. Due to their high sensitivity to the antimicrobial stress as observed at sub-MIC, it is arguably a potential use of thymol for assurance of food safety and hygiene in combination with other preservative technologies. A quantitative evaluation of the antimicrobial properties of the active compound was performed using a macrodilution methodology based on a turbidimetric technique to produce inhibitory data. Both the growth kinetics and inhibition profile in a wide range of thymol concentrations were obtained for each test bacterium, mathematically modeled, and analyzed. Noninhibitory concentration and MIC were determined to investigate both the microbial sensibility and resistance toward thymol, and Gompertz's parameters were evaluated to assess the microbial response at each phase of growth cycle. The in vitro-obtained results suggested that thymol may be successfully used as a alternative preservative to increase the lag time as well as to decrease the maximum cell load reached in the stationary phase of growth cycle for all investigated bacteria.