The Effect of Chlorhexidine on the Push-Out Bond Strength of Calcium-Enriched Mixture Cement

Introduction: The aim of this in vitro study was to evaluate the effect of 2% chlorhexidine (CHX) on the push-out bond strength (BS) of calcium-enriched mixture (CEM) cement. Methods and Materials: Root-dentin slices from 60 single-rooted human teeth with the lumen diameter of 1.3 mm were used. The samples were randomly divided into 4 groups (n=15), and their lumens were filled with CEM cement mixed with either its specific provided liquid (groups 1 and 3) or 2% CHX (groups 2 and 4). The specimens were incubated at 37°C for 3 days (groups 1 and 2) and 21 days (groups 3 and 4). The push-out BS were measured using a universal testing machine. The slices were examined under a light microscope at 40× magnification to determine the nature of bond failure. The data were analyzed using the two-way ANOVA. For subgroup analysis the student t-test was applied. The level of significance was set at 0.05. Results: After three days, there was no significant difference between groups 1 and 2 (P=0.892). In the 21-day specimens the BS in group 3 (CEM) was significantly greater than group 4 (CEM+CHX) (P=0.009). There was no significant difference in BS between 3 and 21-day samples in groups 2 and 4 (CEM+CHX) (P=0.44). However, the mean BS after 21 days was significantly greater compared to 3-day samples in groups 1 and 3 (P=0.015). The bond failure in all groups was predominantly of cohesive type. Conclusion: Mixing of CEM with 2% CHX had an adversely affected the bond strength of this cement

Food texture as affected by ohmic heating: Mechanisms involved, recent findings, benefits, and limitations

peer-reviewedBackground: Food texture is an important quality characteristic that affects sensory perception and consumer satisfaction. Thermal processing applies to food material for several reasons including palatability improvement and shelf life extension. Ohmic heating is an energy- and time-saving technique that was previously proposed as an alternative to conventional heating methods in the food industry. Scope and approach: Investigating the effects of ohmic processes on food quality parameters, such as texture, is an important step towards the industrial adaptation of ohmic heating technology. This review focuses specifically on the effects of ohmic heating on food texture and tries to elucidate the mechanisms behind the changes in textural attributes during an ohmic process as compared to the classical heating method. Key findings and conclusions: Achieving a predefined product texture in a shorter time and the uniformity of product texture are among the benefits of ohmic heating. However, several challenges (e.g. the possibility of negative effects on the chemical composition of the product and high capital investment) should be addressed for the industrial adoption of this emerging technology

Moderate electric fields and ohmic heating as promising fermentation tools

peer-reviewedFermentation is an important bioprocess in food production and its improvements can bring profits to the food industry. Therefore, researchers are exploring the feasibility of applying emerging processing technologies such as moderate electric field (MEF) and ohmic heating to improve this bioprocess. This study demonstrated the current status, potential benefits, mechanisms, and limitations of innovative MEF- and ohmic-assisted fermentation. Research showed that these techniques can positively affect Lactobacillus, Streptococcus, and Saccharomyces fermentations that are involved in the production of bakery (e.g., leavened breads), dairy (e.g., yogurt), and alcoholic products. Also, volumetric ohmic heating can accelerate fermentation by providing optimum fermentation temperatures quickly. MEF-induced stress-response conditions can affect microbial metabolism and fermentation products. Besides, electrical fields may affect the fermentation process by altering the substrate such as releasing its micronutrients. These approaches can be considered prospective industrial fermentation tools. Further economic studies and in-depth research on their effects on fermentation by-products are expected in the near future

Effect of HHP and UHPH High-Pressure Techniques on the Extraction and Stability of Grape and Other Fruit Anthocyanins

Altres ajuts: MALTA CONSOLIDER TEAM Research Network RED2022-134388-TThe use of high-pressure technologies is a hot topic in food science because of the potential for a gentle process in which spoilage and pathogenic microorganisms can be eliminated; these technologies also have effects on the extraction, preservation, and modification of some constituents. Whole grapes or bunches can be processed by High Hydrostatic Pressure (HHP), which causes poration of the skin cell walls and rapid diffusion of the anthocyanins into the pulp and seeds in a short treatment time (2-10 min), improving maceration. Grape juice with colloidal skin particles of less than 500 µm processed by Ultra-High Pressure Homogenization (UHPH) is nano-fragmented with high anthocyanin release. Anthocyanins can be rapidly extracted from skins using HHP and cell fragments using UHPH, releasing them and facilitating their diffusion into the liquid quickly. HHP and UHPH techniques are gentle and protective of sensitive molecules such as phenols, terpenes, and vitamins. Both techniques are non-thermal technologies with mild temperatures and residence times. Moreover, UHPH produces an intense inactivation of oxidative enzymes (PPOs), thus preserving the antioxidant activity of grape juices. Both technologies can be applied to juices or concentrates; in addition, HHP can be applied to grapes or bunches. This review provides detailed information on the main features of these novel techniques, their current status in anthocyanin extraction, and their effects on stability and process sustainability

The combined effect of essential oils and emerging technologies on food safety and quality

Essential oils (EOs) are natural food preservatives, but they may impair the sensory characteristics of foods. Emerging technologies (ETs) can inactivate microorganisms, but high intensities of the process may compromise quality parameters. This manuscript discusses the use of EOs and ETs and presents the mechanisms of microbial inactivation in combined processes. Also, the advantages, disadvantages, and limitations of EO and ETs were explained. It was found that lemongrass, lavender, thyme, sweet basil, lime, oregano, mentha, cinnamon, citral, carvacrol, carvone, geraniol, eugenol, citrus extract, mandarin, rosemary, and clove EOs have been combined with cold plasma, ultrasound, irradiation, ultraviolet light, high hydrostatic processing, pulsed light, pulsed electric fields, ohmic heating, and ozone to inactivate pathogens, spoilage bacteria, and molds. The food matrices explored for EO and ET include meat, fish, eggs, milk, plant-based products, as well as food-container surfaces. Synergistic effects between EOs and ETs have been reported in many cases. Microbial inactivation is influenced by the type of microorganism, the intensity of ET processing parameters, type and concentration of EOs, and the composition of foods. The combined use of EOs and ETs is a strategy capable of reducing the EO doses and the ET intensity while improving food safety and quality

Fucus vesiculosus extracts as natural antioxidants for improvement of physicochemical properties and shelf life of pork patties formulated with oleogels

There is limited information in the literature concerning the feasibility of using algal extracts as natural additives for improvement of the quality and shelf-life ofmeat products. Hence, a Fucus vesiculosus extract (FVE) at the concentrations of 250mg kg-1 (FVE-250), 500mg kg-1 (FVE-500) and 1000mg kg-1 (FVE-1000) were added to pork patties with linseed oil oleogel as a fat replacer. RESULTS: Total polyphenol content of FVE was determined to be 20 g phloroglucinol equivalents 100 g-1 extract. Antioxidant values ranged from 37.5 mol of Trolox equivalents (TE) g-1 (FRAP assay) to 2111 mol TE g-1 extract (ABTS assay). Regarding oxidation stability, FVE-1000 showed the lowest values of thiobarbituric acid-reactive substance and carbonyl content. On the other hand, FVE did not improve color, surface discoloration or odor attributes of patties during storage. Sensory evaluation revealed that there was no significant difference among all studied samples. CONCLUSION: Although FVEs have a high polyphenol content and antioxidant activities, they are not effective oxidation inhibitors for long-term storage of meat products. Therefore, additional measures or compounds should be considered when FVE is the only antioxidant inmeat products.The authors would like to thank Xunta de Galicia (grant number IN607B 2016/28). The authors also thank the Instituto Nacional de Investigaciones Agrarias y Alimentarias, Spain, for granting Ruben Agregán a predoctoral scholarship (CPR2014-0128). Jose M. Lorenzo is a member of the HealthyMeat network, funded by CYTED (ref. 119RT0568). Mohsen Gavahian gratefully acknowledges the support of the Ministry of Economic Affairs, project no. 107-EC-17-A-22-0332, Taiwan (R.O.C). He alsowould like to declare that his main contribution to this work was related to the extraction and antioxidant studies. Amin Mousavi Khaneghah gratefully acknowledges the support of a CNPq-TWAS Postgraduate Fellowship (Grant # 3240274290). Special thanks to Artur J. Martins and Miguel A. Cerqueira for supplying the ‘organogels’ used in this study.info:eu-repo/semantics/publishedVersio

Valorization of wastewater from table olives: NMR identification of antioxidant phenolic fraction and microwave single-phase reaction of sugary fraction

The table olive industry is producing a huge amount of wastewater, which is a post-processing cost and an environmental concern. The present study aims to valorize this processing by-product to obtain a value-added product, thereby enhancing resource efficiency and contributing to achieving sustainable development goals (SDGs). In this sense, a chemical reaction-based platform was developed to obtain valuable components, such as levulinic acid (LA) and 5-hydromethylfurfural (HMF). The products were then analyzed using NMR identification of the antioxidant phenolic fraction and microwave single-phase reaction of the sugary fraction. According to the results, the highest concentration of phenolic compounds does not correspond to the sample directly obtained from NaOH treatment (S1), indicating that water washing steps (S2-S5) are fundamental to recover phenolic substances. Moreover, glucose was presented in the sugary fraction that can be transformed into levulinic acid by a single-phase reaction under microwave irradiation. The information provided in this manuscript suggests that the wastewater from the olive processing industry can be valorized to obtain valuable products

Sequential multi-stage extraction of biocompounds from Spirulina platensis: Combined effect of ohmic heating and enzymatic treatment

A sequential multi-stage procedure was applied on the extraction of biocompounds from Spirulina platensis. The process consisted in three steps: 1) aqueous extraction, using conventional thermal extraction (CE), ohmic heating (OH, 7V/cm), enzymatic treatment (EAE, 0.8 mgLysozyme/mL), or both OH and EAE combined; 2) ethanolic extraction; 3) CHCl3/MeOH extraction. The results evidenced that the combined OH-EAE extraction allowed selective recovery of phycobiliproteins in the 1st step, with increments of more than 100% in yield in comparison with CE. Pigments and lipids were selectively extracted in the 2nd step. The combination of OH and EAE in the 1st step resulted in higher amounts of extracted compounds in the following phases compared to processes using non-combined technologies. Results demonstrate that the intensification of extraction steps facilitates the use of environmentally friendly technologies in a multi-stage process capable of recovering and isolating different fractions with bio-functional properties, targeting waste reduction and circular economy. Industrial relevance Spirulina plantensis represents a potential biomass feedstock due to its potential as a source of compounds of great economic value (including antioxidants, proteins, lipids and natural pigments, in particular blue colorants). The combined use of ohmic heating and enzymes in the aqueous extraction step fosters the use of environmentally friendly technologies to implement sequential high yield and high purity extraction of the different valuable fractions with bio-functional properties, targeting waste reduction and contributing to the implementation of circular economy strategies. This can be integrated with a design of Industry 4.0 driving the development of new products.This research was funded by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit, by program Marie Skłodowska-Curie grant (MSCA-RISE; FODIAC; 778388) and by project OH2O - POCI-01-0145-FEDER-029145 (funded by FCT, COMPETE2020 – Competitiveness and Internationalization Operational Program and European Fund for Regional Development - FEDER). Pedro Santos is recipient of a PhD fellowship supported by a doctoral advanced training (call NORTE-69-2015-15), funded by the European Social Fund under the scope of Norte2020 - Programa Operacional Regional do Norte (NORTE-08-5369-FSE-000036). Sílvia Miranda acknowledges the financial support provided by FCT through the Doctoral grant SFRH/BD/144188/2019. Spirulina platensis was kindly supplied by EVRA S.r.l. (Potenza, Italy).info:eu-repo/semantics/publishedVersio

Data for: Ohmic accelerated steam distillation of essential oil from lavender: energy consumption and physicochemical properties of the extract

This GC-MS graph compares the compositions of the extracted essential oils through SD and OASD