Characterization of autochthonal yeasts isolated from Spanish soft raw ewe milk protected designation of origin cheeses for technological application.

The yeasts involved in the ripening process of artisanal soft raw ewe milk Protected Designation of Origin (PDO) Torta del Casar and Queso de la Serena cheeses produced in Extremadura, Spain, were isolated throughout their ripening process, strain typed, and characterized for some important technological properties. A total of 508 yeast isolates were obtained and identified by inter-single sequence repeat anchored PCR amplification analysis and subsequent sequencing of the internal transcribed spacer ITS1/ITS2 5.8S rRNA. A total of 19 yeast species representing 8 genera were identified. Debaryomyces hansenii, Pichia kudriavzevii, Kluyveromyces lactis, and Yarrowia lipolytica were the predominant species. We selected 157 isolates, by genotyping and origin, for technological characterization. The evaluation of yeast isolates' growth under stress conditions of cheese ripening showed that 87 presented better performance. Among them, 71 isolates were not able to catabolize tyrosine to produce a brown pigment. Principal component analysis of the biochemical features of these isolates showed that 9 strains stood out, 3 K. lactis strains (2287, 2725, and 1507), 2 Pichia jadinii (1731 and 433), 2 Yarrowia alimentaria (1204 and 2150), Y. lipolytica 2495 and P. kudriavzevii 373. These strains displayed strong extracellular proteolytic activity on skim milk agar as well as an adequate enzymatic profile (strong aminopeptidase and weak protease activity), suggesting their great potential for cheese proteolysis. Extracellular lipolytic activity was mainly restricted to Yarrowia spp. isolates and weakly present in P. kudriavzevii 373 and K. lactis 2725, although enzymatic characterization by API-ZYM (bioMérieux SA) evidenced that all may contribute, at least in part, to the lipolysis process. Moreover, these strains were able to assimilate lactose, galactose, and glucose at NaCl concentrations higher than that usually found in cheese. However, lactate and citrate assimilation were limited to Y. lipolytica 2495, P. kudriavzevii 373, and P. jadinii 433, and may contribute to the alkalinizing process relevant to biochemical processes that take place in the last stages of ripening. By contrast, K. lactis strains showed acidifying capacity and ß-galactosidase activity and may take part in the initial stages of ripening, together with lactic acid bacteria. Thus, considering the technological characteristics studied, the 9 selected strains presented biochemical features well suited to their potential use as adjunct cultures, alone or in combination with autochthonous starter bacteria in the cheesemaking process, to overcome the heterogeneity of these PDO cheeses, preserving their unique sensory characteristics.

Gene expression of Aspergillus flavus strains on a cheese model system to control aflatoxin production.

The expression of genes associated with aflatoxin biosynthesis by different Aspergillus flavus strains growing on a cheese model system has not been studied. To control aflatoxin biosynthesis, it would be useful to understand the changes in gene expression during cheesemaking and relate those changes to toxin production. The objective of this study was to evaluate the effects of pH, water activity, and temperature on the expression of 2 regulatory genes (aflR and aflS) and 1 structural gene (aflP) involved in aflatoxin biosynthesis, using 3 aflatoxigenic A. flavus strains growing on a cheese-based medium and reverse-transcription real-time PCR. The gene expression patterns were influenced by A. flavus strain and environmental conditions. The structural gene aflP and the regulatory genes aflR and aflS showed similar expression patterns in each A. flavus strain, but we also observed inter-strain differences. We observed the highest expression levels at 6 and 9 d of incubation by A. flavus strains CQ8 and CQ103, and saw a decrease in the days following. Strain CQ7 showed the lowest expression of these genes. We observed the highest expression levels of these genes at pH 5.5, water activity 0.95, and 20 to 25°C; strain CQ103 showed a different pattern for the aflS gene, with maximum expression at pH 6.0 on d 6 of incubation. For the 3 strains, we found a strong correlation between the relative expression of the aflR and aflS genes and the concentration of aflatoxins under conditions that simulated cheese ripening. Control strategies to avoid aflatoxin contamination during cheesemaking could use the detection of regulatory gene expression.

Cyclopiazonic acid gene expression as strategy to minimizing mycotoxin contamination in cheese.

Expression of genes associated with cyclopiazonic acid (CPA) biosynthesis by Penicillium strains in a cheese-based medium has not been previously studied. To control CPA biosynthesis, it would be useful to understand the changes in gene expression during cheese production and relate them to toxin production. The objective was to evaluate the influence of pH, aw, and temperature on expression of dmaT, which encodes the enzyme dimethylallyl tryptophan synthase involved in the biosynthesis of CPA. We assayed three Penicillium strains, Penicillium commune CBS311 and CBS341 and Penicillium camemberti CBS273, using reverse transcription real-time PCR. Our results showed that the expression patterns of the gene were influenced by strain and environmental conditions. The highest expression for the P. commune strains was observed at pH 6.0, 0.95 aw, at 25 or 30 °C, depending on the strain. In contrast, P. camemberti CBS273 showed a lower dmaT expression with a maximum at 25 °C, pH 5.0 and 0.95 aw. Correlation analysis indicated that the three toxigenic strains showed a strong correlation between the relative expression of the dmaT gene and concentration of CPA under conditions simulating cheese ripening. This method could be used to control CPA production in cheese by detection of dmaT expression.

Strategies to Increase the Biological and Biotechnological Value of Polysaccharides from Agricultural Waste for Application in Healthy Nutrition.

Nowadays, there is a growing interest in the extraction and identification of new high added-value compounds from the agro-food industry that will valorize the great amount of by-products generated. Many of these bioactive compounds have shown beneficial effects for humans in terms of disease prevention, but they are also of great interest in the food industry due to their effect of extending the shelf life of foods by their well-known antioxidant and antimicrobial activity. For this reason, an additional research objective is to establish the best conditions for obtaining these compounds from complex by-product structures without altering their activity or even increasing it. This review highlights recent work on the identification and characterization of bioactive compounds from vegetable by-products, their functional activity, new methodologies for the extraction of bioactive compounds from vegetables, possibly increasing their biological activity, and the future of the global functional food and nutraceuticals market.

Anti-fungal activity of phenolic sweet orange peel extract for controlling fungi responsible for post-harvest fruit decay.

There is a growing interest in finding safe and natural anti-microbial compounds as a valid alternative to conventional chemical treatments for managing post-harvest fruit diseases. This study investigated the anti-fungal capacity of orange peel polyphenolic extract (OPE) against three relevant post-harvest fungal pathogens, Monilinia fructicola, Botrytis cinerea and Alternaria alternata. OPE extract at 1.5 g/L inhibited (100%) the mycelial growth and conidial germination of the three target fungi. At lower concentration, the effect varied, depending on the dose applied and target fungi. When the anti-fungal activity of the main phenolic compounds in sweet orange peel, namely, the flavonoids (naringin, hesperidin and neohesperidin) and phenolic acids (ferulic and p-coumaric), were evaluated, ferulic acid and p-coumaric acid displayed significantly higher inhibitory capacity in synthetic medium, while the activity of flavonoids was limited. Synergism between compounds was not detected, and the inhibitory activity of OPE may be attributed to an additive effect of phenolic acids. Interestingly, in peach-based medium, ferulic acid remained active against M. fructicola and A. alternata and was more efficient than p-coumaric to control B. cinerea. These results highlight peel orange waste as an excellent source of anti-fungal compounds, suggesting the possibility of using ferulic acid or ferulic acid-rich extracts, either alone or in combination with other post-harvest treatment, as a natural alternative to reduce post-harvest losses and, also, enhance the shelf-life of fruit.

Effect of temperature - humidity index on the onset of post- partum ovarian activity and reproductive behavior in Bos indicus cows.

The effect of climatic factors on ovarian activity and reproductive behavior (RB) was evaluated in 46 Bos indicus cows kept under grazing conditions. Temperature-humidity index (THI) was used as an indicator of stress and divided in alert, damage and emergency levels. Fat thickness (FAT) was taken during the last trimester of gestation (LTG) to approximately 90d postpartum (PP). At 30d PP animals received a progesterone (P4)-releasing device (CIDR) which was withdrawn 9d later. Ovarian activity was assessed by blood progesterone on days 21, 24, 27, 30, 49, 51, and 54 PP. Animals were divided into three groups, higher, and moderate RB and non-behavior. Sixty percent presented a THI >74 increasing dramatically from June to September up to >78. During LTG, animals lost 27% of their body reserves contrasting to PP where an increase of 2.6% (P=0.002) was observed. The percentages of cyclic and non-cyclic animals were 57 and 43%, respectively (P> 0.05). Seventy-two percent displayed RB and 28% were non-behavior (P<0.05). A negative correlation (r = -0.307; P = 0.038) between THI and RB, and a positive correlation (r = 0.427; P = 0.003) between the onset of ovarian activity and RB were observed. Differences in THI during the LTG (P<0.01) were observed between cyclic and non-cyclic animals. Non-behavior cows in the LTG had a higher THI (P <0.05). High levels of THI have a negative effect on the resumption of ovarian activity and RB in Bos indicus especially if high THI occurs during the last trimester of gestation.

Characterization of molds isolated from smoked paprika by PCR-RFLP and micellar electrokinetic capillary electrophoresis.

Molds are common contaminants of paprika meat products. The drying and storage stages of paprika processing are critical because they can provide molds with the conditions particularly appropriate for their growth and proliferation. Thus, an efficient and accurate characterization of the toxigenic molds of paprika is necessary. An RFLP analysis of the rRNA genes was performed by using a TaqI restriction enzyme. In addition, a micellar electrokinetic capillary chromatography (MECC) method was tested to analyze secondary metabolites produced by mold strains commonly found in paprika. This study was confirmed with a 5.8S-ITS region sequence analysis. A total of 31 isolates were identified by RFLP and MECC analysis. These showed stable RFLP profiles that were clearly different for the different genera and species, and were grouped into clusters together with the profiles of the 16 reference strains. MECC analysis provided additional characteristic peak patterns for the characterization of the mold species present. The characterized isolates were species of the genera Fusarium spp., Aspergillus spp., Penicillium spp., Cladosporium spp., Mucor spp. and Phlebia spp. The identifications were confirmed by the 5.8S-ITS region sequence analysis and by a BLAST search of the GenBank database. RFLP patterns with TaqI restriction enzyme and MECC profiles, either singly or combined, could be of great interest to distinguish molds in paprika.

Determination of killer activity in yeasts isolated from the elaboration of seasoned green table olives.

In this work 51 yeasts strains isolated from seasoned green table olives and belonging to the Candida, Debaryomyces, Kluyveromyces, Pichia, and Saccharomyces genera were characterized by their killer activity in different conditions. Killer activity of isolates was analyzed in a medium with different pH's (3.5 to 8.5) and NaCl concentrations (5, 8, and 10%). At every pH tested, all the genera studied had killer strains, although the smallest percentages of killer yeasts were found at the highest pH (8.5). The presence of 5 and 8% NaCl increased the detected killer percentage, but the highest salt concentration (10%) decreased it. The interaction between the reference killer yeasts and yeasts isolated from olives was analyzed. Most isolates were killer-sensitive to one or more killer reference strains. Only 2 of the 51 strains tested were considered killer-neutral. Cross-reaction trials between isolates and spoilage yeasts showed that, of the isolates, nine killer strains, belonging to Debaryomyces hansenii, Kluyveromyces marxianus, Pichia anomala, Pichia guilliermondii, and Saccharomyces cerevisiae, had the broadest spectra of action against yeasts that cause spoilage. These killer yeasts and the toxins that they produce are candidates for further investigation as suppressors of indigenous olive table yeast growth. The results confirmed the highly polymorphic expression of the killing activity, with each strain showing different killer activities. This method may thus be very useful for simple and rapid characterization of yeast strains of industrial interest.

Differentiation of Staphylococci from Iberian dry fermented sausages by protein fingerprinting.

The Staphylococci populations in different types of Iberian dry fermented sausages from central-west Spain were identified. A simple electrophoretic method of whole-cell proteins and extracellular protein profiling was evaluated for speed of identification. This study was correlated with a 16S rRNA gene sequence analysis and biochemical identification by API Staph. A total of 81 isolates were identified by SDS-PAGE of the whole-cell proteins. These showed stable profiles in the range 99-14kDa that were clearly different for the different species, and were grouped into clusters together with the profiles of the eight reference strains. SDS-PAGE of the extracellular protein extracts provided additional characteristic banding patterns for the characterization of the Staphylococcus species present. The whole-cell SDS-PAGE showed that the predominant species was Staphylococcus saprophyticus (61.7%) followed by Staphylococcus aureus (19.7%). The identifications were confirmed by the 16S rRNA gene sequencing and by a BLAST search of the GenBank database. However, the API Staph biochemical identifications were frequently erroneous at the species level. In sum, SDS-PAGE analysis showed itself to be rapid and accurate in identifying the most commonly encountered Staphylococcus isolates in dry fermented sausages.

Authentication of "Cereza del Jerte" sweet cherry varieties by free zone capillary electrophoresis (FZCE).

The purpose of this work was to develop a procedure based on protein analysis by free zone capillary electrophoresis (FZCE) that can be used as an alternative to other methods in the determination of sweet cherry varieties for the authentication of "Cereza del Jerte". Two autochthonous varieties of sweet cherry type "Picota", 'Ambrunés' and 'Pico Negro', and the foreign variety 'Sweetheart' were used in the study. Two protocols for extracting the methanol-soluble proteins were tested. On the basis of the results, direct evaporation with nitrogen of a methanol extract was included in the extraction protocol for routine analysis. This method was found to give excellent repeatability of the corrected migration time (CMT), and showed greater effectiveness in discriminating sweet cherry varieties than the SDS-PAGE technique. Three peaks found in the FZCE electropherograms were investigated as a basis for discriminating between varieties. In addition, the FZCE analysis of methanol-soluble proteins provides information about the physico-chemical parameters relevant to the sensorial quality of the sweet cherries.

Characterization of Micrococcaceae isolated from Iberian dry-cured sausages.

The populations of Micrococcaceae in different types of Iberian dry-cured sausages from central-west Spain were characterized and their technological and antimicrobial properties determined in order to evaluate their suitability as starter cultures in dry-cured sausage manufacture. Of a total of four hundred strains isolated from two manufacturers, one hundred and sixty-six were selected to evaluate nitrate reductase, proteolytic, lipolytic, and antimicrobial activities, and growth at different values of pH and water activity (a(w)). Most of the strains were identified as Staphylococcus except for eight isolates assigned to Kocuria spp. The species most often isolated was Staphylococccus xylosus. Others were, in descending order of abundance, S. aureus, S. lugdunensis, S. saprophyticus, S. sciuri, S. chromogenes, and S. capitis. The distributions of the minority Staphylococcus species were different for the two manufacturers. All the investigated strains were able to grow at pH and a(w) greater than 5.0 and 0.85, respectively, the values usually found in Iberian dry-cured sausages. Five S. xylosus strains showed antimicrobial activity against some indicator strains which were investigated. Seven strains with the best properties were pre-selected and tested for their lipolytic and proteolytic activities against pork fat and myofibrillar and sarcoplasmic pork proteins, respectively, and for their low biogenic amines production. Most of the strains showed proteolytic and lipolytic activities, but none produced histamine, tyramine, phenylethylamine, or spermine. Three strains, identified as Staphylococcus xylosus, possess useful properties which make them candidates for testing as starter cultures in pilot processing of Iberian sausages.

Impact of volatile composition on the sensorial attributes of dried paprikas.

Here we characterised the aroma of smoked, oven-dried, and sun-dried paprikas by sensorial evaluation and analysis of their volatile profiles. The sensorial panel defined smoked paprikas as having an intense, persistent, smoked odour and flavour and the highest acceptability. The oven-dried paprikas had a fruity odour and flavour related with aroma notes to fresh peppers. The sun-dried paprikas were associated with straw aromas and the worse valued. The chemical classes of volatile compounds also defined the paprika types. The smoked paprikas were richer in alcohols, phenols, pyrroles, and pyranones, whereas the oven-dried samples were characterised by their aldehydes and terpenes. The sun-dried paprikas had significantly lower amounts of odorant substances than the smoked and oven-dried paprikas. The intensity, persistence and smokiness descriptors (associated with smoked paprika) were positively associated with phenols and alcohols. Aldehydes were positively correlated with a fruity descriptor, which defined oven-dried paprikas, and negatively correlated with intensity, persistence, smokiness, toasted, and dried pepper descriptors. The descriptor straw, which defined sun-dried paprikas, was negatively correlated with alcohols, phenols, furans, and pyrroles.

Contribution of a selected fungal population to the volatile compounds on dry-cured ham.

Dry-cured ham is obtained after several months of ripening. Different fungi strive on the surface, including toxigenic molds. Proteolysis and lipolysis by the endogenous and microbial enzymes seem to play a decisive role in the generation of flavor precursors in dry-cured meat products. In addition, fungi show a positive impact on the volatile compounds of ripened pork loins. However, the contribution of the fungal population to flavor formation in dry-cured ham remains unclear. One selected strain each of Penicillium chrysogenum and Debaryomyces hansenii was inoculated as starter cultures on dry-cured ham. Volatile compounds extracted by solid phase micro-extraction technique were analyzed by gas chromatography/mass spectrometry. A trained panel evaluated flavor and texture of fully ripened hams. The wild fungal population on non-inoculated control hams correlates with higher levels of short chain aliphatic carboxylic acids and their esters, branched carbonyls, branched alcohols, and some sulfur compounds, particularly at the outer muscle. Conversely, P. chrysogenum and D. hansenii seem to be responsible for higher levels of long chain aliphatic and branched hydrocarbons, furanones, long chain carboxylic acids and their esters. The very limited impact of P. chrysogenum on pyrazines in inoculated hams can be due to the activity of the yeast. Lower levels for some of the more volatile linear carbonyls at the ham surface suggest an anti-oxidant effect by micro-organisms. The differences in volatile compounds did not show a neat impact on flavor in the sensorial analysis. Nonetheless, inoculated hams got a better overall acceptability, which has to be attributed to their improved texture. The lower toughness of inoculated hams is a direct consequence of an early settling of a highly proteolytic mold. Thus, the use of selected fungi as starter cultures may be useful to obtain high-quality and safe dry-cured ham.

Detection of smoked paprika "Pimentón de La Vera" adulteration by free zone capillary electrophoresis (FZCE).

The purpose of this work was to develop a procedure based on protein analysis by free zone capillary electrophoresis (FZCE) that can be used in the determination of smoked paprika "Pimentón de La Vera" adulteration with paprika elaborated from varieties of pepper foreign to the "La Vera" region, in central western Spain. Two autochthonous varieties of pepper, Jaranda and Bola, and the variety Papri Queen, foreign to the "La Vera" region, were used in the study. Several aqueous solutions for solubilization of the methanol-soluble proteins were tested, and the FZCE conditions of capillary dimensions, FZCE buffer concentrations, and detection wavelengths were optimized. On the basis of the results, 30% (v/v) acetonitrile was adopted as the suspending solution for routine analysis, and the optimal FZCE parameters were 75 microm inner diameter and 57 cm total length capillaries, 8.75 mM phosphate/20.6 mM tetraborate as run buffer, and 256 nm as detection wavelength. This method was found to give excellent repeatability of the corrected migration time (CMT) with coefficients of variation (RSD %; n = 5) of <1% for most of the proteinaceous compounds analyzed and showed greater effectiveness in discriminating paprika varieties than the SDS-PAGE technique. Four peaks found in the FZCE electropherograms were investigated as a basis for detecting and estimating the adulteration of smoked paprika with paprika elaborated from the Papri Queen variety. The adulteration detection limits varied from 5 to 40% of the Papri Queen variety within a satisfactory working range of mixture (5-80%) sufficiently large to cover the adulteration levels of interest. The use of peak 6 as a marker for determining adulteration gave the best results, with an adulteration detection limit of 5-10% (w/w).

Identification of fungal contamination and determination of mycotoxigenic molds by micellar electrokinetic capillary chromatography in smoked paprika.

The purpose of this work was to analyze the fungal contamination in smoked and unsmoked paprika processed from different cultivars of pepper and to investigate the ability of these and other mycotoxigenic molds to grow and synthesize mycotoxins in smoked paprika. Eighteen mycotoxins were evaluated using micellar electrokinetic capillary chromatography. No relevant differences were found in fungal contamination between smoked and unsmoked paprika. The number of yeasts obtained was low, ranging from 0.4 to 3.29 log CFU g(-1); most of the yeast strains were identified as Cryptococcus spp. followed by Candida spp. All mold counts were <4 log CFU g(-1). Aspergillus, Cladosporium, Penicillium, and Fusarium were the predominant hyphomycete genera. Six mycotoxins were identified in the extracts of several strains isolated from paprika and incubated on malt extract agar. Penicillium expansum followed by Penicillium citrinum and Penicillium raistrickii were the dominant mycotoxigenic fungi isolated. Most of themycotoxin-producing fungi produced detectable amounts of mycotoxins when grown on paprika agar.

Effect of Penicillium chrysogenum and Debaryomyces hansenii on the volatile compounds during controlled ripening of pork loins.

During ripening of meat products such as dry-cured ham, the moulds and yeasts that proliferate on the surface may contribute to flavour development. However, their contribution to volatile components of dry-cured meat products is not known. One strain each of Penicillium chrysogenum and Debaryomyces hansenii, selected from dry-cured ham by their proteolytic activity, were tested to determine their effect on the volatile compounds during ripening. Sterile pork loins were inoculated and ripened for 106 days. Volatile compounds collected with a Solid Phase Micro-Extraction (SPME) fibre were analysed by GC/MS. Inoculation of pork loins with P. chrysogenum lead to a decrease in compounds attributed to lipid oxidation and to an increase of compounds derived from free amino acids. Inoculation with D. hansenii seemed to favour the formation of complex alcohols.

Effect of the fungal protease EPg222 on the sensory characteristics of dry fermented sausage "salchichón" ripened with commercial starter cultures.

The effect of the addition of the fungal protease EPg222 on the sensory characteristics of dry fermented sausage "salchichón" ripened with commercial starter cultures was investigated. Sausages were prepared with purified EPg222 and Staphylococcus carnosus, Staphylococcus xylosus, and Lactobacillus sakei as starter cultures, ripened for 145 days and compared with a control batch only inoculated with the starter cultures. Dry fermented sausages ripened with EPg222 and starter cultures showed higher amount of NPN and volatile compounds derived from amino acid catabolism, than control ripened only with starter cultures. Several branched aldehydes, acids and alcohols such as 2- and 3-methylbutanoic acid and 2-methylpropanol were detected only in enzyme treated samples. Sensory analysis reflected higher values for aroma intensity of sausages treated with EPg222 and lower values of hardness than control. The effect of EPg222 may be of great interest to improve sensory characteristics of dry fermented sausages ripened with starter cultures.

Proteolytic activity of Penicillium chrysogenum and Debaryomyces hansenii during controlled ripening of pork loins.

The role of micro-organisms on the ripening process of dry-cured ham, particularly with respect to proteolysis, is not clear. This is partially due to the lack of an adequate system to study changes on a sterile control meat product for long ripening times. Using a meat system based on sterile pork loins ripened under aseptic conditions for 106 days, the contribution to the proteolysis of two micro-organisms isolated from dry-cured ham has been established. Changes were studied by SDS-PAGE of sarcoplasmic and myofibrillar proteins, capillary zone electrophoresis (CZE) of low ionic strength-soluble nitrogen compounds, and HPLC of free amino acids. Debaryomyces hansenii Dh345 did not show any significant proteolytic activity. However, Penicillium chrysogenum Pg222 showed high proteolytic activity on myofibrillar proteins resulting in an increase in soluble nitrogen compounds. For this, P. chrysogenum Pg222 should be considered to be used as starter culture in meat products made using long ripening times.

Estudio del estado nutricional y de la prevalencia de exceso de peso en adolescentes de localidades extremeñas de diferentes tamaños / A study of the nutritional status and prevalence of overweight among adolescents from different size towns in Extremadura

RESUMEN En este trabajo se determina el estado nutricional de adolescentes de Extremadura y la prevalencia de sobrepeso y obesidad en función del tamaño de la localidad de procedencia. Se realizó un estudio con 816 estudiantes de Educación Secundaria Obligatoria y Bachillerato, de ambos sexos, con edades de 13 a 18 años. Los centros educativos pertenecían a municipios de una Región española, Extremadura, de diferentes tamaños (de menos de 5.000 a más de 60.000 habitantes). Se recogieron datos antropométricos y, siguiendo criterios nacionales e internacionales, se determinaron los porcentajes de sobrepeso y obesidad en función del tamaño de las localidades. Los alumnos de localidades rurales (menores de 5.000 habitantes) tienden a presentar valores de diferentes parámetros antropométricos que se relacionan con un menor desarrollo corporal. Aunque hubo variaciones en la prevalecía de sobrepeso y obesidad en función de los criterios utilizados, las localidades de más de 60.000 habitantes presentaron los mayores porcentajes medios de exceso de peso y las rurales, los menores.

ABSTRACT The aim of this study was to determine the nutritional status and estimate the prevalence of overweight and obesity among adolescents from different size towns in the Extremadura Region of Spain. A sample of 816 secondary school students of both sexes between 13 and 18 years of age were evaluated. The educative centers selected belonged to different size towns (populations between <5,000 and >60,000 inhabitants). Different anthropometric measures were taken. The percentage of teenagers with overweight and obesity was calculated following national and international standards and compared by town size. Students from rural towns, <5,000 inhabitants, had the lowest values in some of the anthropometric measures; results that are associated with a lower body development. There were differences in the prevalence of overweight and obesity based on the criteria used, but, in general, adolescents from larger towns (>60,000 inhabitants) showed the highest percentages of overweight, whereas rural populations showed the lowest percentages.

Use of autochthonous Pediococcus acidilactici and Staphylococcus vitulus starter cultures in the production of "chorizo" in 2 different traditional industries.

UNLABELLED: The present study determined how the different ripening conditions affected the growth and development of 3 autochthonous starter cultures, and the physico-chemical and sensory characteristics of chorizo. Each of 3 strains of Pediococcus acidilactici (MC184, MS198, and MS200) and one of Staphylococcus vitulus (RS34) were associated to prepare the starter cultures, P184S34, P198S34, and P200S34. Then, chorizo was prepared following 2 manufacturing procedures. The autochthonous starter cultures were able to compete and colonize the sausages in both ripening procedures. The use of the starter cultures showed evident differences by the texture analysis, with the control batches being generally tougher than the starter culture batches. Also, the highest biogenic amine (BA) levels were found in control batches and the lowest in P200S34 batches. While the use of these starter cultures does not change the sensory characteristics of these traditional fermented sausages, it improves their homogeneity and safety, except for P184S34 batch in which more BAs are detected in industry 2. PRACTICAL APPLICATION: The 3 autochthonous starter cultures selected could be used in traditional industries because they are able to compete well and colonize the dry fermented sausages "chorizo." The use of these starter cultures improves the texture and homogeneity of traditional fermented sausages. Biogenic amines decreased in the starter cultures batches improving the safety.