Improvement of raw milk cheese hygiene through the selection of starter and non-starter lactic acid bacteria: The successful case of pdo pecorino siciliano cheese

This review article focuses on the technological aspects and microbiological critical points of pressed-cooked cheeses processed from raw ewe’s milk without the inoculation of starter cultures, in particular “Pecorino” cheese typology produced in Italy. After showing the composition of the biofilms adhering to the surface of the traditional dairy equipment (mainly wooden vat used to collect milk) and the microbiological characteristics of PDO Pecorino Siciliano cheese manufactured throughout Sicily, this cheese is taken as a case study to develop a strategy to improve its hygienic and safety characteristics. Basically, the natural lactic acid bacterial populations of fresh and ripened cheeses were characterized to select an autochthonous starter and non-starter cultures to stabilize the microbial community of PDO Pecorino Siciliano cheese. These bacteria were applied at a small scale level to prove their in situ efficacy, and finally introduced within the consortium for protection and promotion of this cheese to disseminate their performances to all dairy factories. The innovation in PDO Pecorino Siciliano cheese production was proven to be respectful of the traditional protocol, the final cheeses preserved their typicality, and the general cheese safety was improved. An overview of the future research prospects is also reported

Biotecnologie applicate alla valorizzazione della \u201cPagnotta di Piana degli Albanesi\u201d

Il presente articolo riassume il progetto di valorizzazione della Pagnotta di Piana degli Albanesi attraverso lo sviluppo di un impasto acido ottenuto da batteri lattici selezionati dalle materie prime, al fine di legare la produzione al territorio e permettere di recuperare le note di tipicit\ue0. Le farine e le semole rappresentano dei veri e propri habitat microbici, la cui composizione pu\uf2 variare in funzione dell\u2019area geografica e delle condizioni di conservazione. Trattandosi di materie prime che non possono essere trattate termicamente prima della trasformazione, esse trasferiscono i loro microrganismi al prodotto in lavorazione. Pertanto, qualora tali microorganismi esprimano propriet\ue0 panarie rappresentano degli utili strumenti per l\u2019esaltazione delle note aromatiche desiderate. Il contributo scientifico riporta le popolazioni lattiche delle materie prime siciliane impiegate nella produzione di pani tipici, la selezione dei batteri lattici e lo scaleup della loro applicazione

Impiego di batteri lattici autoctoni per il miglioramento igienico-sanitario del Pecorino Siciliano DOP

Il Pecorino Siciliano DOP \ue8 considerato il pi\uf9 antico formaggio prodotto in Sicilia e, probabilmente, d\u2019Europa. Le citazioni storiche sulla sua antica origine risalgono al IX secolo a.C. in uno dei passi pi\uf9 famosi dell\u2019odissea di Omero, quando Ulisse incontra Polifemo. In seguito, anche Aristotele e Plinio esaltano il gusto unico di questo formaggio. In particolare, proprio Plinio, nella sua opera \u201cNaturalis Historia\u201d, redige una carta dei formaggi nella quale vengono citati, tra i migliori pecorini,quelli provenienti da Agrigento. Fra le caratteristiche peculiari del Pecorino Siciliano DOP vanno annoverati il sapore leggermente piccante e l\u2019incantevole profumo di pascolo. Il Pecorino Siciliano DOP \ue8 un formaggio a pasta dura, semicotto, prodotto con latte intero crudo di pecora. L\u2019areale di produzione si estende su tutta la regione Sicilia. La forma \ue8 cilindrica a facce piane o lievemente concave, pesa dai 4 ai 12 kg, lo scalzo \ue8 di 10-18 cm. La crosta \ue8 bianca-giallognola,con la superficie rugosa per la modellatura lasciata dal canestro in giunco dove avviene la formatura, spesso viene cappata con olio. La pasta \ue8 compatta, di colore bianco o giallo paglierino, con occhiatura scarsa. Il sapore \ue8 piccante e caratteristico, l\u2019aroma \ue8 intenso. La stagionatura minima prevista dal disciplinare \ue8 di 4 mesi. Il Pecorino Siciliano ha acquisito la certificazione DO nel 1955 e la DOP nel 1996 con regolamento CE n. 1107/96 della Commissione del 12 giugno 1996 (Gazzetta Ufficiale Comunit\ue0 Europea L 148 del 21/6/1996). Attualmente, le attivit\ue0 di promozione, valorizzazione e vigilanza sono affidate al Consorzio di tutela del Pecorino Siciliano DOP, che \ue8 stato riconosciuto dal ministero delle Politiche agricole, alimentari e forestali (Mi- Paaf) dal 2005 a oggi. L\u2019elevata eterogeneit\ue0 del prodotto osservata nelle forme presenti sul mercato \ue8 dovuta sia ai metodi di produzione artigianali sia al vecchissimo disciplinare di produzione, risalente al 1956. Ci\uf2 ha indotto il consorzio di tutela a intraprendere una proficua collaborazione tecnico-scientifica con l\u2019Universit\ue0 degli Studi di Palermo prima e l\u2019Istituto Zooprofilattico Sperimentale della Sicilia, il Corfilac e l\u2019Universit\ue0 di Catania successivamente, con l\u2019obiettivo di migliorare la qualit\ue0 igienico-sanitaria del formaggio Pecorino Siciliano DOP e ridurre l\u2019eccessiva variabilit\ue0 qualitativa fra le forme ottenute da differenti caseificazioni

A review on effects of biological soil crusts on hydrological processes

Biological soil crusts (BSCs) are complex consortia of microorganisms able to modify soil physical, chemical, and hydrological characteristics and influence soil erosion resistance. Given their importance, this paper analyses the current knowledge about BSCs reporting the findings of 163 papers about different BSC aspects published from 1990 to 2023. At first, a review of the BSC main detection methods (visual inspection, remote sensing, and morphological characterization) is presented as they represent valuable tools in BSC identification and mapping, revealing some issues related to the adopted classification criteria and the BSC microbial composition. Then, the literature results about their influence on soil characteristics, hydrology, and erosion processes are reported. Although their positive effects on soil characteristics (e.g., stability and fertility) and resistance to soil erosion are widely recognized, conflicting results are reported on their influence on soil hydrology. The analysis of the available literature allowed for providing indications about the choice of which microorganisms are the most suitable to form BSCs, following the required objectives (soil physic-chemical improvements, soil hydrology, erosion processes resistance, cost, and time to produce their effects). In particular, the results showed that i) the BSC effects on the soil physic-chemical characteristics improve along their successional series; ii) bacteria and cyanobacteria can be considered the most valuable BSC in limiting and degraded conditions (sediment concentration in the runoff reduced by 87% in comparison to bare soils, cost of 350 USD ha−1, and a recovery time of 5–10 years); iii) the intrinsic heterogeneity of BSCs does not allow for explaining the divergence of the literature results on soil hydrology; and iv) mosses are the best BSC anti-erosive type as they produce the most similar effects as compared to vegetation. Finally, the main steps required to obtain microbial inoculums, the effects of their application to induce BSC formation, and future prospects of research are reported

Microbiological investigation of Raphanus sativus L. grown hydroponically in nutrient solutions contaminated with spoilage and pathogenic bacteria

The survival of eight undesired (spoilage/pathogenic) food related bacteria (Citrobacter freundii PSS60, Enterobacter spp. PSS11, Escherichia coli PSS2, Klebsiella oxytoca PSS82, Serratia grimesii PSS72, Pseudomonas putida PSS21, Stenotrophomonas maltophilia PSS52 and Listeria monocytogenes ATCC 19114T) was investigated in mineral nutrient solution (MNS) during the crop cycle of radishes (Raphanus sativus L.) cultivated in hydroponics in a greenhouse. MNSs were microbiologically analyzed weekly by plate count. The evolution of the pure cultures was also evaluated in sterile MNS in test tubes. The inoculated trials contained an initial total mesophilic count (TMC) ranging between 6.69 and 7.78 Log CFU/mL, while non-sterile and sterile control trials showed levels of 4.39 and 0.97 Log CFU/mL, respectively. In general, all inoculated trials showed similar levels of TMC in MNS during the experimentation, even though the levels of the inoculated bacteria decreased. The presence of the inoculums was ascertained by randomly amplified polymorphic DNA (RAPD) analysis applied on the isolates collected at 7-day intervals. At harvest, MNSs were also analyzed by denaturing gradient gel electrophoresis (DGGE). The last analysis, except P. putida PSS21 in the corresponding trial, did not detect the other bacteria, but confirmed that pseudomonads were present in un-inoculated MNSs. Despite the high counts detected (6.44 and 7.24 CFU/g), only C. freundii PSS60, Enterobacter spp. PSS11 and K. oxytoca PSS82 were detected in radishes in a living form, suggesting their internalization

The Post-Traumatic Stress Disorder Checklist for DSM-5: Psychometric Properties of the Italian Version

Background: The present study aimed to investigate the psychometric properties of the Italian version of the PTSD Checklist for the DSM-V (PCL-5) in a group of adults who had experienced heterogenous traumatic events. Methods: Six hundred and one participants met the inclusion criteria and completed a set of questionnaires through an online survey. Before administering the survey, the PCL-5 was translated into Italian according to the back-translation method. The factorial structure of the PCL-5 was assessed through multiple confirmatory factor analyses. Gender measurement invariance and concurrent and criterion validity were also evaluated. Results: The instrument had a seven-factor structure and it worked in a similar manner for males and females. With regard to the concurrent validity, results showed that higher PCL-5 scores were associated with higher levels of depression and rumination and lower levels of life satisfaction. Regarding criterion validity, results revealed that PCL-5 scores were, on average, higher for females than for males, and the temporal distance from the traumatic event was negatively correlated with the total PCL-5 score. Conclusions: The findings indicated that the Italian version of the PCL-5 was able to provide valid and reliable scores for the assessment of PTSD symptoms in the Italian population

Investigación sobre un pasteurizador de túnel para las aceitunas de mesa “Nocellara del Belice” procesadas mediante el “Método Castelvetrano”

The influence of pasteurization temperature and time of treatment on the flesh firmness and the evolution of microbial communities was studied for table olives Cv. Nocellara del Belice, packed in glass jars and processed with a tunnel pasteurizer. The experiment was first carried out on the laboratory level in order to select the optimal combination of pasteurization time/temperature so as to obtain the proper balance between the consistency of the pulp and the microbiological quality of the final product. Pasteurization at industrial scale was then carried out in a tunnel pasteurizer applying the treatment at 75 °C for 8 min in the thermal center of the jars. Besides flesh firmness and microbial evolutions, the pH, total titratable acidity (TTA) and color were evaluated for the table olives during storage at 6, 12 and 15 months from packing. The table olives showed a high stability and acceptable flesh firmness for the entire period under observation. Specifically, olive pulp texture decreased during the storage period, but the softening was most evident in the deeper layers of the pulp. The results indicated that the storage period should not exceed 6 months. Although the hygiene is preserved, after this period the firmness might not be acceptable to consumers.En el presente trabajo se estudió la influencia de la temperatura y del tiempo de pasteurización en la firmeza de la pulpa y la evolución de las comunidades microbianas para la aceituna de mesa “Nocellara del Belice” procesadas con un pasteurizador de túnel. El experimento se llevó a cabo preliminarmente a nivel de laboratorio con el fin de seleccionar la combinación óptima de tiempo/temperatura de pasteurización para obtener el compromiso adecuado entre la consistencia de la pulpa y la calidad microbiológica del producto final. A continuación se llevó a cabo la pasteurización en escala industrial dentro de un pasteurizador de túnel aplicando el tratamiento a 75 ° C durante 8 minutos. Fueron evaluados pH, acidez total titulable (ATT) y el color para las aceitunas de mesa durante el almacenamiento a los 6, 12 y 15 meses de envasado. Las aceitunas de mesa mostraron una alta estabilidad y una firmeza de pulpa aceptable para todo el período de observación; en particular, la textura de pulpa disminuyó durante el período de almacenamiento, pero el ablandamiento fue más evidente en las capas más profundas de la pulpa. Los resultados indicaron que el período de almacenamiento no debe ser superior a 6 meses

An integrated technological approach to the selection of lactic acid bacteria of flour origin for sourdough production

Several lactic acid bacteria (LAB) were evaluated in situ for their potential in sourdough fermentation. The strains belonged to Lactobacillus plantarum, Lactobacillus sakei, Lactobacillus sanfranciscensis, Leuconostoc citreum, Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides and Weissella cibaria. LAB were used, in individual inocula, to carry out the fermentation of \u3b3-ray treated (sterile) flour and untreated commercial flour, in order to evaluate their performances both in the absence and presence of the native microbiota of flour. The pH and total titratable acidity (TTA) showed a strong and fast acidification of the experimental sourdough determined by W. cibaria and Ln. citreum strains. All strains were followed during fermentation by plate count. Randomly amplified polymorphic DNA (RAPD)-PCR analysis applied on the colonies isolated from the highest dilution of samples confirmed the dominance of the added strains in all sourdoughs prepared with sterile and non-sterile flour. The analysis of organic acids, performed by high-performance liquid chromatography (HPLC), confirmed that some W. cibaria and Ln. citreum strains showed an optimal fermentation quotient. The volatile organic compound (VOC) composition resulting from the gas chromatography coupled with mass spectrometry (GC/MS) analysis of sourdough headspace recognised 51 chemical compounds including acids, alcohols, aldehydes, esters, ketones, lactones, acetate, alkane, and phenol, most of which are of LAB origin and are relevant for the final bread. After baking, the breads were evaluated for the height of the central slices, colour of crust and crumb, hardness and number and distribution of alveolus. The combination of these results indicated that strains Ln. citreum PON10079 and PON10080 and W. cibaria PON10030 and PON10032 are suitable cultures to use in industrial production