The Potential Application of Antimicrobial Silver Polyvinyl Chloride Nanocomposite Films to Extend the Shelf-Life of Chicken Breast Fillets

Silver (Ag) nanoparticles (NPs) were synthesised and characterised, and their antimicrobial activity against Escherichia coli, Staphylococcus aureus, Bacillus cereus, Pseudomonas fluorescens and microflora derived from raw chicken, beef or cooked ham was determined. Polyvinyl chloride (PVC) films or antimicrobial Ag/PVC nanocomposite films were manufactured via a solvent casting method and the mechanical and thermal properties of these materials determined. Manufactured antimicrobial Ag/PVC nanocomposite films were used to wrap chicken breast fillets, followed by modified atmosphere packaging (using conventional laminates and employing a gas mix of 60 % N₂/40 % CO₂), and compared against PVC control films. In general, Gram-negative bacteria were more sensitive to Ag NPs than Gram-positive bacteria and microflora isolated from meat products were more resistant than pure culture bacteria. However, the most sensitive bacteria to Ag NPs were Pseudomonas fluorescens. No significant differences (p?>?0.05) in tensile strength and elongation at break were observed, but glass transition temperatures (T _g) of Ag/PVC nanocomposite films were lower (p?<?0.05) when compared to PVC control films. Results also indicated that antimicrobial Ag/PVC nanocomposite films significantly (p?<?0.05) extended the shelf-life of chicken breast fillets and reduced lipid oxidation of chicken breast fillets compared to PVC-wrapped equivalents. Overall, results indicated that antimicrobial Ag/PVC nanocomposite films can potentially be used as antimicrobial packaging for food packaging applications.     

Use of Protein Hydrolysate from Yellow Stripe Trevally (<Emphasis Type="Italic">Selaroides leptolepis</Emphasis>) as Microbial Media

The objective of this study was to investigate the potential use of protein hydrolysate from yellow stripe trevally as a nitrogen source for the growth of different microorganisms. Protein hydrolysates from yellow stripe trevally with different degrees of hydrolysis (5, 15 and 25%) prepared using Alcalase (HA) or Flavourzyme (HF) were determined in comparison with commercial Bacto Peptone. For bacteria, Staphylococcus aureus and Escherichia coli, HF with 25% DH (HF₂₅) yielded the highest cell density and specific growth rate (μ _max) and the lowest generation time (t _d) (p?Saccharomyces cerevisiae and Candida albicans, Bacto Peptone yielded the higher growth rate than did HA and HF (p?μ _max and t _d were observed for fungus, Aspergillus oryzae (p?>?0.05). The pH of culture broth containing HF₂₅ decreased markedly during the first 8 hours of cultivation of S. aureus and E. coli (p?S. aureus (p?25 rendered the similar growth and colony size of S. aureus (p?>?0.05), compared with that containing Bacto Peptone. Scanning electron microscopic study revealed no differences in size and shape of microorganisms cultured in HF₂₅ and Bacto Peptone (p?>?0.05).     

Influence of 10-MeV E-Beam Irradiation and Vacuum Packaging on the Shelf-Life of Grass Carp Surimi

The effects of 10-MeV E-beam (0, 1, 3, 5, and 7 kGy) irradiation and vacuum packaging on extending the shelf-life of grass carp surimi stored at 4 °C were evaluated basing on the total viable counts (TVC), physiochemical 2-thiobarbituric acid reactive substance (TBARS), total base nitrogen (TVB-N), biogenic amines (BAs), texture (TPA) and color, and sensory changes in surimi samples. The results showed that comparing the control samples, the TVC and TVB-N content in surimi were significantly (p?<?0.05) decreased by irradiation with different doses. Irradiation significantly (p?<?0.05) inhibited the increase of putrescine (PUT), cadaverine (CAD), histamine (HIM), and tyramine (TYM) contents during storage. However, these parameters were significantly (p?<?0.05) increased with storage time. After irradiation, the samples generally had higher lightness and lower a ^* and b ^* values and lower hardness and chewiness significantly (p?<?0.05). Based on the sensory analysis, unfavorable ‘metal odor’ or ‘irradiated odor’ was observed in surimi irradiated at 5 and 7 kGy.     

TLC-Digital Image-Based Fluorometric Analysis of Ergosterol and Chitin Content in Food Grains Artificially Infested with <Emphasis Type="Italic">Aspergillus flavus</Emphasis> and <Emphasis Type="Italic">Fusarium verticillioides</Emphasis>

Novel thin-layer chromatography-digital image-based analytical methods were developed for the quantitation of ergosterol and chitin content in six food matrices (rice, wheat, maize, sorghum, groundnut, and sunflower), artificially infested with Aspergillus flavus (MTCC 6513)/Fusarium verticillioides (MRC 826). For ergosterol, single-step method, based on liquid/liquid extraction, was followed by thin-layer chromatography (TLC). Chitin was solubilized using lithium chloride (5%) in dimethyl acetamide and converted to chitosan using 5 N NaOH and subsequently complexed with calcofluor white dye. The absorption and emission maxima of chitosan-calcofluor complex were recorded at λ 350/230 and 430 nm, respectively. The sensitivity based on the limit of detection (LOD) was found to be 100 ng both for ergosterol and chitin analysis. Based on ergosterol and chitin analysis, groundnut and maize were found to be suitable substrates for A. flavus (p?<?0.013 and p?<?0.01), while sorghum followed by groundnut and sunflower were found to be ideal for F. verticillioides (p?<?0.01 and p?<?0.0001) and rice was established as poor substrate as there was no growth on it up to 12 days of incubation. A strong correlation was found between ergosterol and chitin contents with regression (r ²) values of 0.974 and 0.997 in food grains inoculated with A. flavus and F. verticillioides, respectively, during the period of infection. The authenticity of the two methods developed was further confirmed by applying them to commercial food grains and flours. Thus, ergosterol in combination with chitin analysis could be successfully used as an index of fungal contamination employing TLC-digital-based analytical methods.     

Novel Intact Bitter Cassava: Sustainable Development and Desirability Optimisation of Packaging Films

Novel biomaterials and optimal processing conditions are fundamental in low-cost packaging material production. Recently, a novel biobased intact bitter cassava derivative was developed using an intrinsic, high-throughput downstream processing methodology (simultaneous release recovery cyanogenesis). Processing of intact bitter cassava can minimise waste and produce low-cost added value biopolymer packaging films. The objective of this study was to (i) develop and characterise intact bitter cassava biobased films and (ii) determine the optimal processing conditions, which define the most desirable film properties. Films were developed following a Box-Behnken design considering cassava (2, 3, 4 % w/v), glycerol (20, 30, 40 % w/w) and drying temperature (30, 40, 50 °C) and optimised using multi-response desirability. Processing conditions produced films with highly significant (p?<?0.05) differences. Developed models predicted impact of processing conditions on film properties. Desirable film properties for food packaging were produced using the optimised processing conditions, 2 % w/v cassava, 40.0 % w/w glycerol and 50 °C drying temperature. These processing conditions produced films with 0.3 %; transparency, 3.4 %; solubility, 21.8 %; water-vapour-permeability, 4.2 gmm/m²/day/kPa; glass transition, 56 °C; melting temperature, 212.6 °C; tensile strength, 16.3 MPa; elongation, 133.3 %; elastic modulus, 5.1 MPa and puncture resistance, 57.9 J, which are adequate for packaging applications. Therefore, intact bitter cassava is a viable material to produce packaging films that can be tailored for specific sustainable, low-cost applications.     

Potential Production of Healthier Protein Isolate from Broiler Meat using Modified Acid-Aided pH Shift Process

Protein isolates from broiler meat were produced using acid-aided process (AP) with some modifications including prewashing prior to pH shift process (PW), homogenisation with 5 mM citric acid plus 8 mM CaCl₂ (CA) and homogenisation with 5 % ethanol (EA). Significant reduction of total cholesterol, nucleic acids and haemoproteins with improved protein yield and whiteness of the isolate was obtained from all modified process (p?<?0.05). CA was the most effective method in elimination of cholesterol (p?<?0.05). However, PW was the best way to remove nucleic acids and haem proteins (p?<?0.05). Among modified processes, CA gel tended to show the highest breaking force, deformation and whiteness but PW gel had the lowest expressible drip (p?<?0.05). EA possessed a negative effect on gel-forming ability. Therefore, CA or PW was a promising means to produce functional protein isolate with reduced nucleic acids, haem pigments and cholesterol.     

Biodegradable Polymeric Films Incorporated with Nisin: Characterization and Efficiency against <Emphasis Type="Italic">Listeria monocytogenes</Emphasis>

Nisin (0.2 IU per cm² films) containing biodegradable films were produced from pea protein isolate (PPI), whey protein isolate (WPI), and polylactic acid (PLA). Nisin was released over 4 h at 22 °C and 8 h at 4 °C. PPI released more nisin compared to other films suppressing the growth of Listeria monocytogenes (P?<?0.05) based upon diffusion into agar and liquid culture media. The population of bacteria after 48 h in liquid media was 6 CFU/mL (1 log₁₀ increase) in PPI, 8.47 CFU/mL (3.47 log₁₀ increase) in WPI and 9 CFU/mL (4 log₁₀ increase) in PLA, which was significantly lower in protein based films compared to PLA (P?<?0.05). The inhibition zone in agar test was significantly higher (P?<?0.05) in PPI and WPI, compared to PLA film, which might be due to the higher hydration in protein based films. Fourier transform infrared spectroscopy (FTIR) showed that nisin altered the intensity of amide I peaks in protein based films suggesting that nisin can bind to the protein functional groups in PPI and WPI. Thermogram showed that nisin did not influence the glass transition and melting temperatures of the films. Nisin containing films exhibited significantly lower enthalpy compared to control films (P?<?0.05). PeakForce Quantitative Nano Mechanical Property Mapping (PeakForce QNM) was applied to extract material and mechanical properties in PPI, WPI and PLA films with and without nisin. Results showed significant reductions in material and mechanical properties of protein based films containing nisin compared to PLA films.     

A comparative study on cytotoxicity and antiproliferative activities of crude extracts and fractions from Iranian wild-growing and cultivated <Emphasis Type="Italic">Agaricus</Emphasis> spp.

Little is known about anticancer capability of wild-growing mushrooms belonging to Agaricus spp. in comparison with their cultivated counterparts. The present study was done to evaluate in vitro antiproliferative effects of dichloromethane-methanol (1:1, v/v) extracts obtained from several Iranian wild strains of Agaricus spp. in comparison with the cultivated white button mushroom, A. bisporus. The wild brown A. bisporus at 500 µg/mL moderately prevented the growth of human prostate cancer (PC3) and human breast cancer (MCF-7) cell lines by 23.54 and 24.57%, respectively, while the wild strains of A. devniensis and A. gennadii at 500 µg/mL had only marginal inhibitory effects. On the contrary, the cultivated A. bisporus significantly inhibited the cell growth at concentrations as low as 125 µg/mL (p?<?0.05). Further, seven distinct fractions were determined based on thin layer chromatography analysis of the cultivated A. bisporus extract. The only active fraction was found to be eluted by petroleum ether (PE):ethyl acetate (EtOAc) (3:2 v/v) which prevented the growth of MCF-7 and PC3 by 74.00 and 63.5%, respectively at 500 µg/mL. Besides, the fraction imposed obvious cytopathic effects in both cell lines at all the tested concentrations, starting from 125 µg/mL. The findings of this study may validate that the known antioxidant potency of wild Agaricus spp. would not necessarily be correlated to their anticancer activity. This research further validated that some semi-polar antiproliferative compounds could be present in the PE/EtOAc-fraction of the cultivated white button mushroom, which warrants further investigations.     

Study of Ca<Superscript>2+</Superscript>-ATPase Activity and Solubility in the Whole Kuruma Prawn (<Emphasis Type="Italic">Marsupenaeus japonicus</Emphasis>) Meat During Heating: Based on the Kinetics Analysis of Myofibril Protein Thermal Denaturation

Protein denaturation is considered to be the main cause of physicochemical changes in prawns during heating. However, no studies have been analyzed the kinetics of protein denaturation and the relationship between the degree of denaturation and chemical changes. Therefore, we investigated the changes in Ca²⁺-ATPase activity, protein solubility, and total sulfhydryl content of whole prawn meat during heating by determining the thermal denaturation kinetics of the proteins. Activation energies (E _a ) for the denaturation of myosin (183.2 kJ/mol) and actin (178.8 kJ/mol) were obtained by non-isothermal differential scanning calorimetry analysis. Using the kinetic parameters, the distribution of protein denaturation was predicted in whole prawns under arbitrary heating conditions. The results revealed an uneven distribution of the protein denaturation in prawns that was dependent on the heating conditions. Ca²⁺-ATPase activity decreased with increasing heating times at 51 or 85 °C and was strongly related to the average degree of protein denaturation. The results of protein solubility analysis suggested that hydrogen bonds, hydrophobic interactions, and ionic bonds changed with protein denaturation. The number of ionic bonds was reduced, while hydrogen content was enhanced at both temperatures. Hydrophobic interactions increased gradually at 51 °C (p?<?0.05). At 85 °C, hydrophobic interactions increased notably at first (p?<?0.05); however, as heating continued, no significant changes were observed (p?>?0.05). Our results indicate that the extent of protein solubility is significantly correlated with the average degree of protein denaturation during the heating process.     

Antioxidant Activity and Determination of Phenolic Compounds from <Emphasis Type="Italic">Eugenia involucrata</Emphasis> DC. Fruits by UHPLC-MS/MS

Fruits have been the focus of several studies aimed at finding new antioxidant sources for protection against the damage caused by reactive species. In this study, the antioxidant activity and the presence of phenolic compounds in all parts (peel, pulp, and seeds) of Eugenia involucrata DC. fruits were evaluated. DPPH^·, ABTS^·+, and ORAC methods were used to determine the antioxidant activity, and an UHPLC-MS/MS method was developed for determining the phenolic compounds (gallic, chlorogenic, ferulic, p-coumaric and ellagic acids, quercetin, and myricetin). In the determination of both antioxidant activity and phenolic composition, the efficiency of solvents with different polarities—methanol/H₂O (80:20, v/v), ethanol/H₂O (80:20, v/v), methanol/acidified water with phosphoric acid pH 3.00 (80:20, v/v), and ethyl acetate—for the extraction of the phenolic compounds, was also evaluated. All parts of E. involucrata fruits showed antioxidant activity, in the range of 36.68 ± 1.44 to 873.87 ± 18.24 μmol TE g^?1, being the highest values found in the seeds and peel when more polar extraction solvents were used. Six, five, and three phenolic compounds were identified and quantified in the pulp, peel, and seeds, respectively, with the highest abundance as p-coumaric acid (14 ± 2 mg kg^?1) in the pulp, quercetin (47 ± 5 mg kg^?1) in the peel, and gallic acid (74 ± 4 mg kg^?1) in the seeds, also when more polar solvents were used. Although antioxidant activity methods suggested that the peel and seeds have more antioxidant potential, a wider variety of compounds were determined in the pulp.     

Modeling the Inactivation of <Emphasis Type="Italic">Listeria innocua</Emphasis> and <Emphasis Type="Italic">Escherichia coli</Emphasis> in Fresh-Cut Tomato Treated with Pulsed Light

The effectiveness of pulsed light (PL) treatments to inhibit microorganisms on fresh-cut tomatoes (Lycopersicon esculentum Mill., cv. Daniela) was investigated. Tomato slices inoculated with Escherichia coli or Listeria innocua were exposed to PL treatments (4, 6, or 8 J cm^?2 fluence) and kept cold at 4 °C for 20 days. L. innocua and E. coli counts, gases in the headspace of the containers (O₂ and CO₂), pH, titratable acidity, and soluble solid content were monitored throughout the cold storage. The PL treatments reduced significantly (p < 0.05) initial loads of both microbes. The effect of the PL fluence on the survival number of microoganisms was described by a log-linear model (R ² = 0.849–0.999). At any fixed time within the cold storing, the microbial counts for untreated samples were always higher than those cut tomatoes that had been previously PL-treated. The behavior of L. innocua and E. coli during the storage were well adjusted (R ² > 0.930) by Gompertzian models; the studied microorganisms exhibited different patterns during the storage period. On the other hand, O₂ and CO₂ partial pressures in containers with fresh-cut tomatoes were also significantly affected by PL treatments (p < 0.05). The highest PL fluence caused the greatest changes of O₂ and CO₂ contents. In addition, the application of PL triggered an acceleration of the O₂ consumption during the cold stage. PL treatments might be used to effectively extend the safety of fresh-cut tomatoes over 12 days of storage against E. coli and L. innocua growth.     

Quality Enhancement of Chilled Lean Fish by Previous Active Dipping in <Emphasis Type="Italic">Bifurcaria bifurcata</Emphasis> Alga Extract

The present study addressed the quality enhancement of chilled fish by applying a preliminary dipping treatment containing a bioactive extract of the alga Bifurcaria bifurcata. Megrim (Lepidorhombus whiffiagonis) specimens were dipped in ethanolic–aqueous solutions containing two different concentrations of the alga extract (high: HAC batch and low: LAC batch). Two types of control batch were considered (ethanol–water dipping and no dipping). Microbial, chemical and sensory qualities were monitored in fish throughout a 13-day storage period. An inhibitory effect (p?<?0.05) of the dipping treatment (washing and the presence of alga extract) on microbial activity was observed, as determined by microbial (Enterobacteriaceae, lipolytic bacteria and psychrotrophs) and chemical (trimethylamine and free fatty acid formation) analyses. In most cases, this effect was found to be more intense for prolonged storage times and in fish specimens corresponding to the HAC batch. However, the combined effect of washing and the inclusion of alga extract in the dipping medium did not affect (p?>?0.05) the rate of lipid oxidation events during storage. Interestingly, average scores revealed increased sensory quality in megrim corresponding to the HAC batch for prolonged storage (9–13 days). Consequently, the use of a bioactive extract of B. bifurcata alga as a preliminary dipping treatment can be considered of interest for further fish storage due to both its simplicity and beneficial effects on fish quality enhancement.     

Rapid Determination of Ethanol in Sugarcane Spirit Using Partial Least Squares Regression Embedded in Smartphone

Mobile devices were used to quantify ethanol content—via colorimetry—in cachaça samples to great analytical precision. Ethanol from the spirits reacted with ceric ammonium nitrate (CAN) and nitric acid (NA) to form a red-colored complex. Images from the reaction were taken over time using a smartphone device and processed using software PhotoMetrix Pro® via partial least squares (PLS). A priori, Doehlert matrix was used for optimization of reagents concentration in the complexation reaction, with hierarchical cluster analysis (HCA) as estimation method and a flatbed scanner as measuring tool. When compared with the UV-VIS reference method, results from mobile device imaging presented a root mean square error of prediction (RMSEP) of 0.0677% (v/v). A t test showed there is no significant difference between methods (P?<?0.05).     

Validation of a HS-SPME-GC Method for Determining Higher Fatty Esters and Oak Lactones in White Rums

Higher fatty esters and oak lactones are the main components of white rum aroma and furthermore, they have an important sensorial impact in these distilled alcoholic beverages. A method for analyzing these volatile compounds was validated. It involves a separation and concentration step using headspace solid-phase microextraction (HS-SPME) and determination by capillary gas chromatography using flame ionization detection. The method showed a good within-day (RSD?<?3 %) and between-day precision (RSD?<?5 %). The calibration curves were linear at the tested ranges (R?>?0.99) and the limits of detection and quantification were 0.001–0.018 and 0.003–0.054 mg L^?1 (12 %?v/v alcohol), respectively. Good recoveries were obtained (98.6–100.3 %). The method is suitable for the quality control of higher fatty esters and oak lactones in white rums.     

Effects of selected herb extracts on iron-catalyzed lipid oxidation in soybean oil-in-water emulsion

Effect of herb extracts on the oil oxidation of an oil-in-water emulsion containing iron was studied. The emulsion comprised tocopherol-stripped soybean oil (40 g), citrate buffer (60 g, pH 4.0), xanthan gum (35mg), and FeSO₄ (0.5mg) with 80% ethanol extracts of rosemary (Rosmarinus officinalis), basil (Ocimum basilicum), peppermint (Mentha piperita), thyme (Thymus vulgaris), or oregano (Origanum vulgare). Hydroperoxide contents and p-anisidine values were significantly (p<0.05) lower in the emulsions with the added herb extracts compared with the control emulsions. The antioxidant activity of the basil and peppermint extracts containing higher proportions of rosmarinic acid was significantly higher (p<0.05) than that of the other herb extracts, but the polyphenol degradation rate was not significantly different. The antioxidant activity of the basil and peppermint extracts showed concentration-dependence within 400 mg/kg. This study suggests that the oxidative stability of oil-inwater emulsion containing iron can be improved by addition of basil or peppermint extract.     

Assessment of the Effects of Ultrasonics and Pulsed Electric Fields on Nutritional and Rheological Properties of Raspberry and Blueberry Purees

The impact of pulsed electric fields (PEF) in continuous, ultrasonication (US), and combined methods was evaluated in red raspberry (Rubus strigosus) and blueberry (Vaccinium corymbosum) purees in order to assess their effects on nutritional quality and rheology. Nonenzymatic browning was inhibited, but only US and combined methods were capable to inactivate polyphenol oxidase (PPO) in a considerable extent (p?<?0.01). High recovery of biocompounds was observed, with a significant extraction (p?<?0.01) of flavonoids (+20 %) and anthocyanins (+30 %) in raspberry and blueberry purees, respectively. Ascorbic acid was preserved, and the gentle effect of nonthermal technologies in antioxidant capacity was confirmed by DPPH? scavenging value, which significant increased for raspberry (p?<?0.01). The rheology of purees was dramatically modified by US, especially in blueberry, showing a progressive shift from non-Newtonian to Newtonian model, accompanied with a reduction in apparent viscosity values. Overall, the enhanced nutritional quality makes both technologies suitable for berry treatment, although changes on rheological properties should be taken into account for process design.     

Quality Enhancement of Chilled Fish by Including Alga <Emphasis Type="Italic">Bifurcaria bifurcata</Emphasis> Extract in the Icing Medium

Bifurcaria bifurcata is a widely extended brown macroalga, whose antimicrobial and antioxidant properties have previously been described. In this study, ethanolic extracts of B. bifurcata were included in the icing medium employed for the chilled storage of megrim (Lepidorhombus whiffiagonis). For it, two different concentrations of this brown macroalga extract (0.67 and 2.50 g lyophilized alga L^?1 aqueous solution; B-1 and B-2 batches, respectively) were tested for a 14-day storage. The effect of the alga extract was compared with a counterpart batch stored in traditional ice prepared only from water (B-0 batch). Significant (p < 0.05) inhibitions of microbial activity (aerobes, psychrotrophs, lipolytic bacteria, proteolytic bacteria and Enterobacteriaceae) as well as of pH and trimethylamine formation were observed as a result of the incorporation of the alga extract in the icing medium, being this effect especially relevant in the B-2 batch. Concerning lipid damage development, a significantly (p < 0.05) lower formation of free fatty acids (lipid hydrolysis development) and of fluorescent compounds (tertiary lipid oxidation development) in samples corresponding to both alga-including batches could also be observed; this inhibitory effect was more intense in fish belonging to the B-2 batch. The icing medium proposed in this work constitutes a promising strategy in order to apply algae extracts to enhance fish quality retention during the different steps of storage and commercialization of marine species.     

Combined Effect of Icing Medium and Red Alga <Emphasis Type="Italic">Gracilaria verrucosa</Emphasis> on Shelf Life Extension of Indian Mackerel (<Emphasis Type="Italic">Rastrelliger kanagurta</Emphasis>)

Flake ice refrigeration is a conventional but commonly employed technique to slow down fish spoilage and deterioration of nutritional values and sensory properties during chilled storage. In the present study, a methanolic extract of red alga Gracilaria verrucosa was characterised, and functional groups, such as alkenes, aldehydes, nitriles, galactans and galactose-4-sulphate were found. Subsequent identification of active compounds revealed the presence of potent preservative agents, such as butylated hydroxytoluene, sulfurous acid, 1,2-propanediol, benzeneacetic acid, cyclononasiloxane and tetracosamethyl-cyclododecasiloxane. The effect of incorporating G. verrucosa at two different concentrations (0.67 and 2.5 g lyophilised alga/L aqueous solution) in the icing medium was tested for the preservation of Indian mackerel (Rastrelliger kanagurta), compared to preservation in traditional ice prepared only from water. Microbial, chemical and sensory qualities were monitored in Indian mackerel chilled in ice with and without G. verrucosa during 15 days storage period. Inhibitory effects (p?<?0.05) on the microbial proliferation (mesophilic and psychrophilic bacteria) and chemical markers of fish deterioration (pH, TVB-N, TMA-N and biogenic amines) were evidenced for ice containing both concentrations of G. verrucosa, respectively, relative to the control medium. The sensory score acceptability limit reached 11 days for Indian mackerel stored in traditional ice and 15 days for Indian mackerel stored in ice with G. verrucosa extract. Thus, the icing medium containing G. verrucosa extract improves the quality and safety of Indian mackerel during storage and can be explored by the seafood industry as a biopreservative.     

Optimization of Extraction Parameters of Total Phenolics from <Emphasis Type="Italic">Annona crassiflora</Emphasis> Mart. (Araticum) Fruits Using Response Surface Methodology

In this study, response surface methodology was used to optimize the extraction temperature (25–75 °C) and ethanol concentration (0–70 %, ethanol/water, v/v) to maximize the extraction of total phenolic compounds (TPC) from araticum pulp. The efficiency of the extraction process was monitored over time, and equilibrium conditions were reached between 60–90 min. A second-order polynomial model was adequately fit to the experimental data with an adjusted R ² of 0.9793 (p < 0.0001) showing that the model could efficiently predict the TPC content. Optimum extraction conditions were ethanol concentration of 46 % (v/v), extraction temperature of 75 °C and extraction time of 90 min. Under the optimum conditions, the araticum pulp showed high TPC content (4.67 g GAE/100 g dw) and also high antioxidant activity in the different assays used (46.56 μg/mL, 683.65 μmol TE/g and 1593.72 μmol TE/g for DPPH IC₅₀, TEAC and T-ORAC_FL, respectively). From our extraction procedure, we successfully recovered a significantly higher amount of TPC compared to other studies in the literature to date (1.5–22-fold higher). Furthermore, TPC and antioxidant activity were present in the fruit in levels that are difficult to find in other common fruits. These results expose a potential approach for improving human health through consumption of araticum fruit.     

High Power Ultrasound: Impact on Olive Paste Temperature,Malaxation Time,Extraction Efficiency,and Characteristics of Extra Virgin Olive Oil

High power ultrasound (HPU) provides rapid heating of olive paste and disrupts cell walls, helping small oil droplets exit tissue and coalesce. This has been shown to improve oil yield and reduce malaxation time without affecting oil quality. Indirect and direct HPU at different treatment times were examined on Arbequina and Frantoio olive pastes. Olive pastes were mixed at four different malaxation times to evaluate extraction efficiency. Additionally, oil yield and different quality parameters were observed. HPU increased olive paste temperature from 20?±?0.5 to 25.5 °C, achieving the optimum kneading temperature of 29?±?1 °C in less mixing time. HPU significantly (P?<?0.05) improved oil yield by 1% for both varieties. There were no significant differences (P?>?0.05) in oil yield between 35 and 45 min malaxation time, suggesting the possibility to reduce malaxation by 10 min with HPU. No significant differences (P?>?0.05) were observed in any quality parameters observed, except peroxide value, which increased slightly. Significant increases (P?<?0.05) in total tocopherol and pigments with increasing HPU treatment time occurred, while a decrease in total polyphenol and oxidative stability index resulted after 8 min treatment. HPU influenced L, a, and b values causing the oil to become darker. Sensory results showed no differences between commercially available and HPU-treated samples. These results suggest the possibility of using HPU treatment to increase oil extraction capacity and yield without loss of product quality.