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Background: Very young children, and those with disabilities and extensive oral pathology, who cannot be treated in the dental chair, require deep sedation or general anesthesia for dental treatment. Objective: The aim of this study is to describe and compare the oral health status in healthy and SHCN children and the treatments performed under deep sedation on an outpatient basis with a minimal intervention approach, and their impact on quality of life. Methods: A retrospective study between 2006 and 2018 was made. A total of 230 medical records of healthy and SHCN children were included. The data extracted were age, sex, systemic health status, reason for sedation, oral health status before sedation, treatments administered during sedation, and follow-up. The quality of life after deep sedation of 85 children was studied through parental questionnaires. Descriptive and inferential analyses were made. Results: Of the 230 children, 47.4% were healthy and 52.6% were SHCN. The median age was 7.10 ± 3.40 years (5.04 ± 2.42 in healthy children and 8.95 ± 3.09 in SHCN children). The main reason for sedation was poor handling in the dental chair (99.5%). The most frequent pathologies were caries (90.9%) and pulp pathology (67.8%). Healthy children had more teeth affected by decay and with pulp involvement. Patients aged < 6 years received more pulpectomies and pulpotomies. After treatment, parents stated that children were more rested and less irascible, ate better, increased in weight, and had improved dental aesthetics. Conclusions: Differences in treatments carried out did not depend on the general health status or the failure rate but on age, with more pulp treatments in healthy children who were younger, and more extractions near to the age of physiological turnover in children with SHCN who were older. Intervention under deep sedation with a minimally invasive treatments approach met the expectations of parents and guardians, as it improved the children’s quality of life.

The effects of high hydrostatic pressure (HHP) compared to thermal pasteurization (TP) were studied in healthy citrus-maqui beverages. The impact of the processing technologies on the microbiological and phytochemical profile was assessed by applying two HHP treatments at 450 and 600 MPa for 180 s and TP at 85 °C for 15 s. The shelf life under refrigeration (4 °C) and room temperature (20 °C) was monitored for 90 days. All treatments ensured microbiological stability at both storage temperatures. Aside from that, the physicochemical parameters were not significantly different after processing or throughout the storage period. Regarding color parameters, an increase in the reddish coloration was observed during storage for those beverages treated by HHP. In general, phenolic compounds were little affected by the processing technique, even when treatment under HHP was more stable than by TP during storage. On the other hand, vitamin C showed great degradation after processing under any condition. It can be concluded that HHP is an effective alternative to thermal treatments, achieving effective microbial inactivation and extending the shelf life of the juices by contributing to a better preservation of color and bioactive compounds.

Consumers’ demands for ready-to-eat, fresh-like products are on the rise during the last years. This type of products have minimal processing conditions that can enable the survival and replication of pathogenic microorganisms. Among them, Listeria monocytogenes is of special concern, due to its relatively high mortality rate and its ability to replicate under refrigeration conditions. Previous research works have shown that nanoemulsified essential oils in combination with thermal treatments are effective for inactivating L. monocytogenes. However, previous research works were limited to isothermal conditions, whereas actual processing conditions in industry are dynamic. Under dynamic conditions, microorganism can respond unexpectedly to the thermal stress (e.g. adaptation, acclimation or increased sensitivity). In this work, we assess the combination of nanoemulsified D-limonene with thermal treatments under isothermal and dynamic conditions. The nanoemulsion was prepared following an innovative methodology using soya lecithin, a natural compound as well as the essential oil. Under isothermal heating conditions, the addition of the antimicrobial enables a reduction of the treatment time by a factor of 25. For time-varying treatments, dynamic effects were relevant. Treatments with a high heating rate (20 °C/min) are more effective than those with a slow heating rate (1 °C/min). This investigation demonstrates that the addition of nanoemulsified D-limonene can greatly reduce the intensity of the thermal treatments currently applied in the food industry. Hence, it can improve the product quality without impacting its safety.

Cooking vegetables in microwave bags is becoming a popular domestic cooking method, being relevant to know how this cooking method affects health-promoting phytochemicals of staples such as broccoli. The aim of this work was to study the effect of microwave bag cooking versus conventional microwaving on bioactive compound content (glucosinolates and hydroxycinnamic acid derivatives) and other quality parameters (such as antioxidant capacity, mineral content and microbial load) of broccoli florets. The influence of cooking time on bioactive compounds content was also evaluated. The study was carried out in two independent experiments; using intact broccoli and broccoli preprocessed in industry. Microwave bag cooked broccoli for 5 min (following label recommendation) showed higher glucosinolate content retention compared to conventional microwaving. Results suggest that volatilization could be an important phenomenon in reduction of glucosinolates during microwave cooking of broccoli florets. Glucosinolate profile did not change after cooking, regardless of cooking method applied. Furthermore, microwave bag cooked broccoli presented higher antioxidant capacity (by DPPH assay) than conventional microwaved broccoli. Hydroxycinnamic acid derivatives content was reduced in microwave cooking, regardless of method applied. Altogether, the use of microwave bags for microwaving is a novel method that retains main bioactive components of broccoli. This option is a fast, easy and considerably clean cooking option to fulfill modern consumer needs., This work was supported by Comision ´ Sectorial de Investigacion ´ Científica, Universidad de la República. Authors are indebted to Agencia Nacional de Innovacion ´ e Investigacion ´ for granting Erika Paulsen a PhD scholarship and an internship at Phytochemistry and Healthy Foods Laboratory of the Department of Food Science and Technology at CEBAS-CSIC (scholarship reference: POS_EMHE_2018_1_1007740)

The application of oily antimicrobials in form of nanoemulsion has been proved to solve the problem of their immiscibility in aqueous media, still preventing microbial growth and even improving the antimicrobial effect observed when applied directly. At present, only a few documented studies have evaluated the combined effect of nanoemulsions with other factors of stress for the microorganism. The present research shows very promising results on the combination of nanoemulsified d -limonene with thermal treatments on the inactivation of Listeria monocytogenes . The thermal resistance of L . monocytogenes was reduced two to five times when 0.5 mM d -limonene was added directly to the heating medium. However, when the same concentration of d -limonene was present in the heating medium in form of nanoemulsion, the heat resistance was reduced by one hundred times at all heating temperatures tested. The addition of nanoemulsified antimicrobials would allow to reduce greatly the intensity of the thermal treatments currently applied in the food processing industry.

In this paper, a novel technique to achieve precise temperatures in food sterilization has been proposed. An accurate temperature profile is needed in order to reach a commitment between the total removal of pathogens inside the product and the preservation of nutritional and organoleptic characteristics. The minimal variation of the target temperature in the sample by means of a monitoring and control software platform, allowing temperature stabilization over 100 °C, is the main goal of this work. A cylindrical microwave oven, under pressure conditions and continuous control of the microwave supply power as function of the final temperature inside the sample, has been designed and developed with conditions of single-mode resonance. The uniform heating in the product is achieved by means of sample movement and the self-regulated power control using the measured temperature. Finally, for testing the sterilization of food with this technology, specific biological validation based on Bacillus cereus as a biosensor of heat inactivation has been incorporated as a distribution along the sample in the experimental process to measure the colony-forming units (CFUs) for different food samples (laboratory medium, soup, or fish-based animal by-products). The obtained results allow the validation of this new technology for food sterilization with precise control of the microwave system to ensure the uniform elimination of pathogens using high temperatures. This work was supported by the Ministerio de Economía y Competitividad under the project with reference DPI2014-61857-EXP.

Heat resistance of microorganisms can be affected by different influencing factors. Although, the effect of heating rates has been scarcely explored by the scientific community, recent researches have unraveled its important effect on the thermal resistance of different species of vegetative bacteria. Typically heating rates described in the literature ranged from 1 to 20°C/min but the impact of much higher heating rates is unclear. The aim of this research was to explore the effect of different heating rates, such as those currently achieved in the heat exchangers used in the food industry, on the heat resistance of Escherichia coli. A pilot plant tubular heat exchanger and a thermoresistometer Mastia were used for this purpose. Results showed that fast heating rates had a deep impact on the thermal resistance of E. coli. Heating rates between 20 and 50°C/min were achieved in the heat exchanger, which were much slower than those around 20°C/s achieved in the thermoresistometer. In all cases, these high heating rates led to higher inactivation than expected: in the heat exchanger, for all the experiments performed, when the observed inactivation had reached about seven log cycles, the predictions estimated about 1 log cycle of inactivation; in the thermoresistometer these differences between observed and predicted values were even more than 10 times higher, from 4.07 log cycles observed to 0.34 predicted at a flow rate of 70 mL/min and a maximum heating rate of 14.7°C/s. A quantification of the impact of the heating rates on the level of inactivation achieved was established. These results point out the important effect that the heating rate has on the thermal resistance of E. coli, with high heating rates resulting in an additional sensitization to heat and therefore an effective food safety strategy in terms of food processing. This research was financially supported by the Ministry of Economy and Competitiveness of the Spanish Government and European Regional Development Fund (ERDF) through project AGL2013-48993-C2-1-R

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The microbial safety and stability of minimally processed foods are based on the application of combined preservative factors. Since microorganisms are able to develop adaptive networks to survive under conditions of stress, food safety may be affected, and therefore understanding of stress adaptive mechanisms plays a key role in designing safe food processing conditions. In the present study, the viability and the sublethal injury ofListeria monocytogenesexposed to moderate heat (55°C) and/or essential oil compounds (carvacrol and thymol, 0.3 mM) treatments were studied. Synergistic effects were obtained when combining mild heat (55°C) with one or both essential oil compounds, leading to inactivation kinetics values three to four times lower than when using heat alone. All the treatments applied caused some injury in the population. The injury levels ranged from around 20% of the surviving population under the mildest conditions to more than 99.99% under the most stringent conditions. Protein extracts of cells exposed to these treatments were analysed by two-dimensional gel electrophoresis. The results obtained revealed that stressed cells exhibited differential protein expression to control cells. The proteins upregulated under these stressing conditions were implicated, among other functions, in stress response, metabolism, and protein refolding.

The antibacterial action of carvacrol and cymene on two Listeria monocytogenes strains (STCC4031 and NCTN4032) was studied. Carvacrol or cymene showed inhibitory effect on the growth of L. monocytogenes during lag and exponential growth phases and was more evident with increasing concentrations in brain heart infusion broth at 30 degrees C. Carvacrol or cymene also decreased the survival of mid-exponential-growth-phase L. monocytogenes STCC4031 cells in potassium-N-2-hydroxy-ethylpiperazine-N-ethanesulfo nic acid, at 30 degrees C. The combination of carvacrol and cymene resulted in an increased antibacterial effect on the growth and a synergistic effect on the viability of L. monocytogenes compared with the natural compounds applied separately. The analysis of survival curves by the Weibull frequency distribution function allowed an accurate prediction of the level of inactivation achieved. Interestingly, an important bactericidal effect (4.7-log reduction) of low concentrations of both antimicrobials combined (0.75 mM) was observed on L. monocytogenes in carrot juice. This study indicates the potential use of carvacrol and cymene applied simultaneously for preservation of minimally processed foods.

The antibacterial action of thymol and cymene on two Bacillus cereus strains (INRA-AVTZ415 and INRA-AVZ421) was studied. Thymol and cymene alone showed higher antibacterial effect on the growth of B. cereus in BHI at 30 °C, both in lag and in exponential growth phases, with increasing added concentrations. However, the two strains tested showed different sensitivity to these natural compounds. When thymol and cymene were applied simultaneously, it resulted in a greater antibacterial effect than when the compounds were applied separately. The synergistic behaviour of both compounds was also shown for lag phase B. cereus INRA-AVZ421 cells in food substrates (carrot juice, chicken soup and pumpkin cream) at 30 °C, though a clear food-related effect was observed. This study indicates the potential use of thymol and cymene applied simultaneously for preservation of minimally processed foods.

Different inactivation kinetics data have been used to predict the number of survivors exposed to a heat treatment and, in consequence, to design thermal processes for the food industry. In this work, spores of an acidophilic strain of Bacillus subtilis were heated under isothermal and non-isothermal conditions. Experimental results obtained after isothermal treatments were analysed using the classical two-step linear regression procedure and a one-step non-linear regression method. Data obtained after non-isothermal treatments were analysed using a one-step, non-linear procedure. Kinetic parameters obtained from isothermal heating were close, either using the two-step linear regression (D 100=6.5 min) or the one-step non-linear regression (D 100=6.3 min), although the second method gave smaller 95% confidence intervals. The z values derived from non-isothermal heating were higher than those obtained in isothermal conditions (z=9.3 °C for non-isothermal heating at 1 °C/min versus z=7.7 °C for isothermal heating one step non-linear regression). Results were validated with experimental data obtained after different heat treatments, consisting of a phase of temperature increase at a fixed rate, followed by a holding phase. Non-isothermal methods predicted accurately the number of survivors after the heating ramp, while isothermal methods were more accurate for the holding phase of the treatment. When a temperature profile of a typical heat treatment process applied in the food industry was simulated, all predictions were on the safe side.

A new microbiological predictive model was developed, relating pH, NaCl concentration and temperature (T) with the decimal reduction coefficient D as dependent variable, using data previously reported by [1]. The model was obtained by multiple linear regression using only three predictor variables (T 2, pH2 and NaCl), easily computed from the basic variables pH, NaCl concentration and temperature (T). The fitted model is robust, stable and satisfies all the basic hypotheses of the regression models. It also provides simplicity when compared with previously published models based on multiple linear regression tools.

To monitor the ability of the food-borne opportunistic pathogen Bacillus cereus to survive during minimal processing of food products, we determined its heat-adaptive response. During pre-exposure to 42°C, B. cereus ATCC 14579 adapts to heat exposure at the lethal temperature of 50°C (maximum protection occurs after 15 min to 1 h of pre-exposure to 42°C). For this heat-adaptive response, de novo protein synthesis is required. By using two-dimensional gel electrophoresis, we observed 31 heat-induced proteins, and we determined the N-terminal sequences of a subset of these proteins. This revealed induction of stress proteins (CspB, CspE, and SodA), proteins involved in sporulation (SpoVG and AldA), metabolic enzymes (FolD and Dra), identified heat-induced proteins in related organisms (DnaK, GroEL, ClpP, RsbV, HSP16.4, YflT, PpiB, and TrxA), and other proteins (MreB, YloH, and YbbT). The upregulation of several stress proteins was confirmed by using antibodies specific for well-characterized heat shock proteins (HSPs) of B. subtilis . These observations indicate that heat adaptation of B. cereus involves proteins that function in a variety of cellular processes. Notably, a 30-min pre-exposure to 4% ethanol, pH 5, or 2.5% NaCl also results in increased thermotolerance. Also, for these adaptation processes, protein synthesis is required, and indeed, some HSPs are induced under these conditions. Collectively, these data show that during mild processing, cross-protection from heating occurs in pathogenic B. cereus , which may result in increased survival in foods.

Two different effects of calcium were studied, respectively, in plasma membrane vesicles and in protoplasts isolated from roots of control pepper plants (Capsicum annuum L cv. California) or of plants treated with 50 mM NaCl, 10 mM CaCl(2) or 10 mM CaCl(2) + 50 mM NaCl. Under saline conditions, osmotic water permeability (P ( f )) values decreased in protoplasts and plasma membrane vesicles, and the same reduction was observed in the PIP1 aquaporin abundance, indicating inhibitory effects of NaCl on aquaporin functionality and protein abundance. The cytosolic Ca(2+) concentration, [Ca(2+)](cyt), was reduced by salinity, as observed by confocal microscope analysis. Two different actions of Ca(2+) were observed. On the one hand, increase in free cytosolic calcium concentrations associated with stress perception may lead to aquaporin closure. On the other hand, when critical requirements of Ca(2+) were reduced (by salinity), and extra-calcium would lead to an upregulation of aquaporins, indicating that a positive role of calcium at whole plant level combined with an inhibitory mechanism at aquaporin level may work in the regulation of pepper root water transport under salt stress. However, a link between these observations and other cell signalling in relation to water channel gating remains to be established.

Natural antimicrobials are an alternative to the use of chemically synthesized preservatives and other technological treatments. They have the advantage of not being rejected by consumers because of their natural origin. However, prior to their usage at a food factory scale, their precise effects on microorganisms have to be known. Nisin, a bacteriocin, and carvacrol and thymol, phenolic compounds present in the essential oil fraction of Oreganum and Thymus plants, have been shown to inhibit growth of different bacteria. This research was conducted to show the effect of a thermal treatment, applied previously, on the growth of B. megaterium cells in a culture medium with and without nisin, carvacrol and thymol. It has been shown that a thermal treatment able to kill 90 % of the spore population of B. megaterium had little effect on the growth of the survivors in nutrient broth at 30 °C. Nisin, in a concentration of 0.05 mM, did not affect greatly the growth of unheated B. megaterium. When the same concentration of nisin was applied to the survivors of the heat treatment, lag phase was further increased and growth rate decreased. Thymol, applied at a concentration of 0.6 mM, increased the lag phase duration almost three times, although it did not change the growth rate. Although carvacrol, at the same concentration (0.6 mM), did reduce the growth rate to half its original value, it did not increase the lag phase duration significantly (only twice), resulting in a quite similar growth curve. The combination of thymol and carvacrol at these high doses (0.6 mM) resulted in a further increase of the lag phase and significant decrease of the growth rate. When carvacrol and/or thymol were combined with a previous thermal treatment (able to kill 90 % of the population), the growth of the survivors was inhibited for at least seven days. Therefore a combination of moderate conditions could be effective to control spoilage by sporeforming bacteria., Prirodna antimikrobna sredstva su alternativa kemijski sintetiziranim konzervansima i drugim tehnološkim postupcima. Njihova je prednost u tome što su zbog svoga prirodnog podrijetla prihvatljivi potrošačima. Prije njihove primjene u prehrambenoj industriji, potrebno je znati kako djeluju na mikroorganizme. Nisin, bakteriocin, te karvakrol i timol, fenolni spojevi prisutni u frakcijama eteričnog ulja biljaka Oreganum i Thymus, inhibiraju rast raznih bakterija. Opisano je istraživanje provedeno da bi se utvrdio učinak prethodno provedene toplinske obrade na rast stanica B. megaterium u podlozi s nisinom, karvakrolom i timolom te bez njih. Pokazalo se da toplinska obrada može usmrtiti 90 % populacije spora B. megaterium, a gotovo nikako ne utječe na rast preživjelih u hranjivoj podlozi pri 30 °C. 22 P.M. PERIAGO et al.: B. megaterium Spore Germination and Growth Inhibition, Food Technol. Biotechnol. 44 (1) 17–23 (2006) Nisin koncentracije od 0,05 mM nije bitno utjecao na rast toplinski neobra|enog B. megaterium. Kada se ista koncentracija nisina primijeni na preživjele spore, produlji se lag faza, a smanji brzina rasta. Timol koncentracije od 0,6 mM produžio je trajanje lag faze skoro 3 puta, a nije promijenio brzinu rasta. Iako je karvakrol iste koncentracije (0,6 mM) smanjio brzinu rasta na polovinu originalne vrijednosti, dužinu lag faze produžio je samo za 2 puta, što je rezultiralo skoro jednakom (0,6 mM) krivuljom rasta. Kombinacijom tih velikih koncentracija timola i karvakrola znatno je produljena lag faza i smanjena brzina rasta. Kada se karvakrol i/ili timol kombiniraju s prethodnom toplinskom obradom (pri čemu je uništeno 90 % populacije), rast preživjelih bio je inhibiran barem 7 dana. Stoga kombinacija jednostavnih uvjeta može biti djelotvorna u kontroli onečišćenja sa sporulirajućim bakterijama

6 pages, 3 tables, 4 figures., Dietary ellagic acid and related polyphenols are metabolized in humans to dibenzopyran-6-one derivatives, and the microbial origin of these metabolites has been suggested. However, this has not been demonstrated so far. Fecal samples donated by six volunteers were incubated under anaerobic conditions, and aliquots were used to evaluate the fecal metabolism of ellagic acid, the ellagitannin punicalagin, and an ellagitannin rich extract from walnuts. The isoflavone daidzein was also incubated with the same fecal samples to follow the production of the microbial metabolites previously reported (dihydrogenistein, O-demethylangolensin, and equol) as a positive control of the system and to evaluate similarities between isoflavone and ellagic acid fecal flora metabolism. After fermentation the metabolite “urolithin A” (3,8-dihydroxy-6H-dibenzo[b,d]pyran-6-one) was produced from ellagic acid, punicalagin, and the ellagitannin extract in all the fecal cultures from different volunteers, but with very different production rates and concentrations. This large variability in the concentration of metabolite and kinetics of metabolite production is consistent with the large variability found in the excretion of these metabolites in urine in vivo after human consumption of ellagitannins, and with differences in the composition of the fecal microflora. No correlation between isoflavone and ellagic acid metabolism by fecal microflora was observed. The present study confirms the microbial origin of the recently reported in vivo generated hydroxy-6H-dibenzo[b,d]pyran-6-one derivatives in humans and is a further step in the study of the bioavailability and metabolism of ellagic acid and ellagitannins., This investigation has been supported by Spanish CICYT, projects AGL2003-02195 and AGL-2004-03989, and by the “Fundación Séneca”, project PB/18/FS/02. B.C. and P.P. have fellowships from the Spanish “Consejo Superior de Investigaciones Científicas” (CSIC) and ESF (I3P Programme).