Potential Prebiotic Effect of Inulin-Enriched Pasta after In Vitro Gastrointestinal Digestion and Simulated Gut Fermentation.

In the current study, the prebiotic potential of an innovative functional pasta enriched with 12% (w/w) inulin was investigated. To this aim, pasta was subjected to in vitro gastrointestinal digestion followed by simulated gut fermentation compared to the control pasta (CTRL) not containing inulin. The incorporation of inulin positively (p < 0.05) affected some organoleptic traits and the cooking quality of the final product, giving an overall score significantly higher than CTRL. The resultant essential amino acid content was similar in both pasta samples while the total protein content was lower in inulin-enriched pasta for the polymer substitution to durum wheat flour. The prebiotic potential of chicory inulin was preliminarily tested in in vitro experiments using seven probiotic strains and among them Lacticaseibacillus paracasei IMPC2.1 was selected for the simulated gut fermentation studies. The positive prebiotic activity score registered with the probiotic strain suggested the suitability of the inulin-enriched pasta with respect to acting as a prebiotic source favoring the growth of the probiotic strain and short chain fatty acid (SCFA) production. The present study contributes to broadening knowledge on the prebiotic efficacy of inulin when incorporated into a complex food matrix.

Synecology of Lagoecia cuminoides L. in Italy and evaluation of functional compounds presence in its water or hydroalcoholic extracts.

Lagoecia cuminoides L. is a very rare and threatened taxon in Italy, never studied before for its ecology and potential use for human consumption. Furthermore, few data are available on the biological activities of its metabolites. A phytosociological study was carried out in the only two Italian sites, and its state of conservation was also evaluated according to the IUCN (International Union for Conservation of Nature) protocol. The collected plant material was used to make two types of extracts: hot water infusion to evaluate the use of this plant as tea and hydroalcoholic extraction to evaluate the use of it in herbal liqueur preparation. The presence of functional compounds in the extracts were investigated by gas and liquid chromatography coupled to mass spectrometry techniques. Ten non volatiles compounds were identified in the extracts, most of which derivatives of quercetin. Thirty-five volatiles compounds were also identified in the plant aerial part and extracts belonging to the chemical class of terpenoids, and among them ß-farnesene, thymol, γ-terpinene and p-cymene were the most abundant. The species is characterized by compounds known for their health effects and for its potential applications for human consumption, being this species already used as decoction in some countries of Middle East. Thanks to its characteristic behaviour to grow in limiting pedoclimatic conditions this species can be potentially used in organic farms situated in rural marginal areas.

Modeling of Growth and Organic Acid Kinetics and Evolution of the Protein Profile and Amino Acid Content during Lactiplantibacillus plantarum ITM21B Fermentation in Liquid Sourdough.

The application of mathematical modeling to study and characterize lactic acid bacterial strains with pro-technological and functional features has gained attention in recent years to solve the problems relevant to the variabilities of the fermentation processes of sourdough. Since the key factors contributing to the sourdough quality are relevant to the starter strain growth and its metabolic activity, in this study, the cardinal growth parameters for pH, temperature (T), water activity (aw), and undissociated lactic acid of the sourdough strain Lactiplantibacillus plantarum ITM21B, were determined. The strain growth, pH, organic acids (lactic, acetic, phenyllactic, and hydroxy-phenyllactic), total free amino acids, and proteins were monitored during fermentation of a liquid sourdough based on wheat flour and gluten (Bio21B) after changing the starting T, pH, and inoculum load. Results demonstrated that the different fermentation conditions affected the strain growth and metabolite pattern. The organic acid production and growth performance were modeled in Bio21B, and the resulting predictive model allowed us to simulate in silico the strain performances in liquid sourdough under different scenarios. This mathematical predictive approach can be useful to optimize the fermentation conditions needed to obtain the suitable nutritional and technological characteristics of the L. plantarum ITM21B liquid sourdough.

Characterization of Dextran Produced by the Food-Related Strain Weissella cibaria C43-11 and of the Relevant Dextransucrase Gene.

A metabolic feature of lactic acid bacteria (LAB) is the production of exopolysaccharides (EPSs), which have technological and functional properties of interest to the food sector. The present study focused on the characterization of the Weissella cibaria strain C43-11, a high EPS producer in the presence of sucrose, in comparison with a low-producing strain (C2-32), and on possible genetic regulatory elements responsible for the modulation of dextransucrase (dsr) genes expression. NMR analysis of the polymeric material produced by the C43-11 strain indicated the presence of dextran consisting mainly of a linear scaffold formed by α-(1-6) glycosidic linkages and a smaller amounts of branches derived from α-(1-2), α-(1-3), and α-(1-4) linkages. Molecular analysis of the dsr genes and the putative transcriptional promoters of the two strains showed differences in their regulatory regions. Such variations may have a role in the modulation of dsr expression levels in the presence of sucrose. The strong upregulation of the dsr gene in the C43-11 strain resulted in a high accumulation of EPS. This is the first report showing differences in the regulatory elements of the dsr gene in W. cibaria and indicates a new perspective of investigation to identify the regulatory mechanism of EPS production.

A Predictive Growth Model for Pro-technological and Probiotic Lacticaseibacillus paracasei Strains Fermenting White Cabbage.

Bacterial strains belonging to Lacticaseibacillus paracasei species are generally used as starters in food fermentations and/or as probiotics. In the current study, the growth cardinal parameters of four L. paracasei strains (IMPC2.1, IMPC4.1, P40 and P101), isolated from table olives or human source, were determined. Strains were grown in liquid medium and incubated at several temperatures (10 values from 5.5°C-40°C) and pH (15 values from 3.2 to 9.1) along the growth range. The cardinal temperature model was used to describe temperature effects on the maximum specific growth rate of L. paracasei whereas new equations were developed for the effect of pH. The estimated Tmin values ranged between -0.97°C and 1.95°C and were lower than 0°C for strains IMPC4.1 and P101. Strain P40 was able to grow in the most restricted range of temperature (from 1.95°C to 37.46°C), while strain IMPC4.1 was estimated to survive at extreme conditions showing the lowest pHmin . Maximum specific growth rates of L. paracasei IMPC2.1 in white cabbage (Brassica oleracea var. capitata) were used to calculate the correction factor (Cf ) defined as the bias between the bacterial maximum specific growth rate in broth and in the food matrix. A simple bi-linear model was also developed for the effect of temperature on the maximum population density reached in white cabbage. This information was further used to simulate the growth of L. paracasei strains in cabbage and predict the time to reach the targeted probiotic level (7 log10 CFU/g) using in silico simulations. This study demonstrates the potential of the predictive microbiology to predict the growth of beneficial and pro-technological strains in foods in order to optimize the fermentative process.

Ecological and Biological Properties of Satureja cuneifolia Ten. and Thymus spinulosus Ten.: Two Wild Officinal Species of Conservation Concern in Apulia (Italy). A Preliminary Survey.

This study evaluated the effects of ecology (plant community, topography and pedology), as well as of climate, on the composition of essential oils (EOs) from two officinal wild plant species (Lamiales) from Apulia, namely Satureja cuneifolia Ten. and Thymus spinulosus Ten. Few scientific data on their chemical composition are available, due to the fact that the first has a limited distribution range and the second is endemic of southern Italy. Results for both species, never officially used in traditional medicine and/or as spices, showed that the ecological context (from a phytosociological and ecological point of view) may influence their EO composition, and hence, yield chemotypes different from those reported in the literature. S. cuneifolia and Th. spinulosus can be considered good sources of phytochemicals as natural agents in organic agriculture due to the presence of thymol and α-pinene. Overall, the obtained trend for EOs suggests a potential use of both species as food, pharmacy, cosmetics and perfumery. Hence, their cultivation and use represent a positive step to reduce the use of synthetic chemicals and to meet the increasing demand for natural and healthier products.

Ecological and Plant Community Implication on Essential Oils Composition in Useful Wild Officinal Species: A Pilot Case Study in Apulia (Italy).

The study focused on the effects of ecology (plant communities and topographical data) on composition of essential oils (EOs) of some officinal wild plant species (Lamiales): Clinopodium suaveolens, Salvia fruticosa subsp. thomasii, Satureja montana subsp. montana, and Thymbra capitata, in different environments of Apulia (Italy). C. suaveolens and S. fruticosa subsp. thomasii are rare species of conservation interest, while S. montana subsp. montana and T. capitata, have a wide distribution and are used in traditional medicine or as spices. Results showed that the ecological context (phytosociological and ecological features) may influence the composition of EOs of the studied species. High differences in the compound composition have been found in S. montana subsp. montana, whereas minor effects were observed in C. suaveolens, S. fruticosa subsp. thomasii, and T. capitata accessions. The understanding of such aspects is necessary for providing optimal conditions to produce EOs rich in compounds known for their biological activities. The results are of great interest also for EOs producers and at the same time to improve our knowledge and valorize wild officinal plants.

Kidney transplant patients with SARS-CoV-2 infection: The Brescia Renal COVID task force experience.

The outcome of kidney transplant patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is still unclear. Here we describe the clinical characteristics, disease outcome, and risk factors for acute respiratory distress syndrome (ARDS) and death of a cohort of 53 kidney transplant patients with coronavirus disease 2019 (COVID-19). Eight of 53 have been handled as outpatients because of mild disease, on average with immunosuppression reduction and the addition of hydroxychloroquine and azithromycin; no patients required admission, developed ARDS, or died. Because of severe symptoms, 45/53 required admission: this cohort has been managed with immunosuppression withdrawal, methylprednisolone 16 mg/d, hydroxychloroquine, and antiviral drugs. Dexamethasone and tocilizumab were considered in case of ARDS. About 33% of the patients developed acute kidney injury, 60% ARDS, and 33% died. In this group, thrombocytopenia was associated to ARDS whereas lymphopenia at the baseline, higher D-dimer, and lack of C-reactive protein reduction were associated with risk of death. In the overall population, dyspnea was associated with the risk of ARDS and age older than 60 years and dyspnea were associated with the risk of death with only a trend toward an increased risk of death for patients on tacrolimus. In conclusion, SARS-CoV-2 infection may have a variable outcome in renal transplant patients, with higher risk of ARDS and death in the ones requiring admission.

Effect of Amaranth and Quinoa Flours on Exopolysaccharide Production and Protein Profile of Liquid Sourdough Fermented by Weissella cibaria and Lactobacillus plantarum.

Exopolysaccharides (EPSs) are known for their positive contribute to the technological properties of many foods, including bakery products. These molecules can be obtained performing piloted fermentation with lactic acid bacteria (LAB). In order to select strains able to produce EPS, a screening test in agar medium containing sucrose, fructose or glucose as carbohydrate source was performed on 21 LAB strains. Results allowed to select 8 Weissella cibaria, 2 Weissella confusa, and 2 Leuconostoc spp. strains as EPS producers only in the presence of sucrose. A further screening in liquid medium enriched with sucrose (10%) (mMRS_S) indicated the W. cibaria strain C43-11 as the higher EPS producer. The selected strain was used to develop liquid sourdoughs (LSs) with dough yield (DY) 500, fermented for 15 h and based on wheat flour and wheat gluten or pseudocereals (quinoa or amaranth) in ratio 1:1, in the presence or not of sucrose at 3% (w/w, LS weight), in comparison to Lactobacillus plantarum ITM21B, a strain not producing EPS in mMRS_S. Results indicated that the use of pseudocereals favored the EPS production. Formulations were optimized by modifying DY (500 or 250), sucrose concentration (3 or 6%) and flour ratio. LSs were characterized for the content of organic acids (lactic, acetic, phenyllactic, OH-phenyllactic), pH, TTA, EPS, viscosity, total protein degradation and protein pattern. The highest EPS production (20.79 g/kg) and viscosity (1168 mPa s) were obtained in LS (DY 250, sucrose 6%) based on quinoa flour and started with C43-11 strain. The LS was characterized by the presence of phenyllactic and OH-phenyllactic acids, protein degradation by 51.7% and proteins in the range 14-80 kDa. In these conditions, also strain ITM21B was able to produce EPS at level of 4.61 g/kg and to degrade proteins by 53.8% in LS based on wheat and quinoa flours (1:1) (DY250 and sucrose 3%). Therefore, results demonstrated that the use of selected conditions (flour type, DY, sucrose) can stimulate specific attributes of strains making them suitable for production of short fermented (15 h) LSs which can be used as bread improvers.

A report from the Brescia Renal COVID Task Force on the clinical characteristics and short-term outcome of hemodialysis patients with SARS-CoV-2 infection.

The SARS-CoV-2 epidemic is pressuring healthcare systems worldwide. Disease outcomes in certain subgroups of patients are still scarce, and data are needed. Therefore, we describe here the experience of four dialysis centers of the Brescia Renal COVID Task Force. During March 2020, within an overall population of 643 hemodialysis patients, SARS-CoV-2 RNA positivity was detected in 94 (15%). At disease diagnosis, 37 of the 94 (39%) patients (group 1) were managed on an outpatient basis, whereas the remaining 57 (61%) (group 2) required hospitalization. Choices regarding management strategy were made based on disease severity. In group 1, 41% received antivirals and 76% hydroxychloroquine. Eight percent died and 5% developed acute respiratory distress syndrome (ARDS). In group 2, 79% received antivirals and 77% hydroxychloroquine. Forty two percent died and 79% developed ARDS. Overall mortality rate for the entire cohort was 29%. History of ischemic cardiac disease, fever, older age (over age 70), and dyspnea at presentation were associated with the risk of developing ARDS, whereas fever, cough and a C-reactive protein higher than 50 mg/l at disease presentation were associated with the risk of death. Thus, in our population of hemodialysis patients with SARS-CoV-2 infection, we documented a wide range of disease severity. The risk of ARDS and death is significant for patients requiring hospital admission at disease diagnosis.

A single center observational study of the clinical characteristics and short-term outcome of 20 kidney transplant patients admitted for SARS-CoV2 pneumonia.

The outcome of SARS-CoV2 infection in patients who have received a kidney allograft and are being treated with immunosuppression is unclear. We describe 20 kidney transplant recipients (median age 59 years [inter quartile range 51-64 years], median age of transplant 13 years [9-20 years], baseline eGFR 36.5 [23-47.5]) with SARS-CoV2 induced pneumonia. At admission, all had immunosuppression withdrawn and were started on methylprednisolone 16 mg/day, all but one was commenced on antiviral therapy and hydroxychloroquine with doses adjusted for kidney function. At baseline, all patients presented fever but only one complained of difficulty in breathing. Half of patients showed chest radiographic evidence of bilateral infiltrates while the other half showed unilateral changes or no infiltrates. During a median follow-up of seven days, 87% experienced a radiological progression and among those 73% required escalation of oxygen therapy. Six patients developed acute kidney injury with one requiring hemodialysis. Six of 12 patients were treated with tocilizumab, a humanized monoclonal antibody to the IL-6 receptor. Overall, five kidney transplant recipients died after a median period of 15 days [15-19] from symptom onset. These preliminary findings describe a rapid clinical deterioration associated with chest radiographic deterioration and escalating oxygen requirement in renal transplant recipients with SARS-Cov2 pneumonia. Thus, in this limited cohort of long-term kidney transplant patients, SARS-CoV-2 induced pneumonia is characterized by high risk of progression and significant mortality.

Management of Patients on Dialysis and With Kidney Transplantation During the SARS-CoV-2 (COVID-19) Pandemic in Brescia, Italy.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as coronavirus disease (COVID-19), is a major pandemic challenging health care systems around the world. The optimal management of patients infected with COVID-19 is still unclear, although the consensus is moving toward the need of a biphasic approach. During the first phase of the disease (from onset of the symptoms up to 7-10 days) viral-induced effects are prominent, with the opportunity to institute antiviral therapy. In the second inflammatory phase of the disease, immunosuppressive strategies (for example with glucocorticoids or anticytokine drugs) may be considered. This latter stage is characterized by the development of progressive lung involvement with increasing oxygen requirements and occasionally signs of the hemophagocytic syndrome. The management of the disease in patients with kidney disease is even more challenging, especially in those who are immunosuppressed or with severe comorbidities. Here we present the therapeutic approach used in Brescia (Italy) for managing patients infected with COVID-19 who underwent kidney transplantation and are receiving hemodialysis. Furthermore, we provide some clinical and physiopathological background, as well as preliminary outcome data of our cohort, to better clarify the pathogenesis of the disease and clinical management.

[Managing patients in dialysis and with kidney transplant infected with Covid-19].

We are in the midst of a health emergency that is totally new for us all and that requires a concerted effort, especially when it comes to safeguarding patients on hemodialysis, and kidney transplant recipients. Brescia is currently a very active cluster of infections (2918 cases on the 17/03/2020), second only to Bergamo. The way our structure is organised has allowed us to treat nephropathic patients directly within the Nephrology Unit, following of course a great deal of reshuffling; at the moment, we are treating 21 transplanted patients and 17 on hemodialysis. This has led us to adopt a systematic approach to handling this emergency, not only in managing inpatients, but also in researching the new disease. Our approach is mirrored in the guidelines attached to this article, originally intended for internal use only but potentially very useful to our colleagues, as they face the same exact problems. We have also started collecting data on our positive patients with the aim of understanding better the functioning of this disease and how best to manage it. If anyone is interested, we ask you to please get in touch with us, so we can coordinate our efforts.

Microbiological and physicochemical parameters for predicting quality of fat and low-fat raw ground beef during refrigerated aerobic storage.

The aim of the current study was to identify quality indicators of fat (14.50 ± 0.75%) and low-fat (4.79 ± 0.63%) raw ground beef by monitoring changes in physicochemical and microbiological parameters during aerobic refrigerated storage, such as water-holding capacity, pH, thiols, carbonyl compounds, thiobarbituric acid reactive substances (TBARS), metmyoglobin, deoxymyoglobin, oxymyoglobin color indices, pseudomonads, Brochothrix thermosphacta, and total viable counts. Meat packaged in air-permeable polyethylene plastic film was stored under controlled isothermal conditions (0, 5, 10, and 15 °C). A population level of pseudomonads equal to 7.0 ± 0.5 log10 colony forming units (CFU)/g was considered as the potential spoilage level. Using principal component analysis, samples were distinguished on the basis of their microbial load. A significant positive correlation between microbial population and carbonyls, metmyoglobin, TBARS, water-holding capacity, and a negative correlation with thiols and color parameters (L* , chroma) were observed. Two different approaches were followed to estimate the quality status of samples: (i) the partial least square (PLS) regression with R2 of 0.93 and root mean square error prediction of 0.44 for pseudomonads, using the above physicochemical characteristics as the dominant input variables, which allowed prediction of the microbiological status of ground beef regardless of time-temperature storage profile and fat content, and (ii) a square-root-type model (adjusted R2 of 0.952) that satisfactorily predicted the growth of spoilage pseudomonads under isothermal and dynamic conditions, regardless of the above physicochemical changes. The above results suggest that depending on the available input data, the two modeling approaches can accurately (and complementarily) assess quality of aerobically stored ground beef. PRACTICAL APPLICATION: Changes in appearance and quality of fat and low-fat raw ground beef are associated with physicochemical alteration and/or microbial growth. The study provides two different modeling approaches that can be integrated in an intelligent interface of the refrigerator having specific colorimetric and/or temperature sensors, to evaluate in a convenience way the quality of stored meat thus reducing domestic waste: the partial least square model was based on physicochemical parameters (particularly chroma, metmyoglobin, and thiobarbituric acid reactive substances), while the square root model was based on the time-temperature conditions during storage.

Thermoplastic starch and bioactive chitosan sub-microparticle biocomposites: Antifungal and chemico-physical properties of the films.

In this study, chitosan (C) tripolyphosphate (T) sub-micro particles containing ungeremine (CTUn), an alkaloid particularly active against Penicilliumroqueforti, a fungus responsible of the bakery products deterioration, were prepared through external gelation crosslinking process. The particles were included in a thermoplastic starch based polymer Mater-Bi (MBi), and MBi/CTUn bioactive biocomposites were obtained. The films showed bioactivity against P. roqueforti. In particular, the bioassays were performed on films with different concentration of CTUn and at different pH values. CTUn particles influenced MBi crystallization (DSC analysis) and promoted thermal degradation of MBi starch component (TGA). Morphological analysis confirmed even distribution of sub-micro particles into the polymeric matrix. Water permeability slightly increased, as expected, whereas oxygen permeability decreased. Tensile tests showed CTUN sub-microparticles improved rigidity and tensile strength of the films at the expense of ductility. Finally, MBi/CTUn biocomposites evidenced interesting performances potentially exploitablein bioactive bakery based food packaging materials.

Use of a Selected Leuconostoc Citreum Strain as a Starter for Making a "Yeast-Free" Bread.

The aim of this study was the characterization and selection of bacterial strains suitable for the production of a "yeast-free" bread. The strains Leuconostoc citreum C2.27 and Weissella confusa C5.7 were selected for their leavening and acidification capabilities and individually used as starters in bread-making tests. Liquid type-II sourdoughs, singly inoculated with the two selected strains, were characterized and employed for bread-making, through the set-up of a biotechnological protocol without the use of baker's yeast as a leavening agent. Aiming to verify the ability of the selected strains to dominate the fermentation process, bacteria and yeasts were isolated from liquid sourdoughs and doughs, genetically characterized and identified. Both the selected strains were suitable for the production of bread, even if L. citreum C2.27 showed the highest leavening capacity and was able to dominate the dough microbiota. The effects of different salt concentrations on the selected strain performances were also investigated. The applicability of the developed protocol, adapted for the production of the typical Apulian bread, "puccia", and the suitability of the strain L. citreum C2.27 were confirmed at pilot scale in an industrial bakery. The puccia bread, which was produced with the liquid sourdough fermented with L. citreum C2.27, without baker's yeast and salt, was similar in appearance to the conventional product containing baker's yeast and was judged positively by a sensory analysis.

Lactobacillus plantarum ITM21B fermentation product and chickpea flour enhance the nutritional profile of salt reduced bakery products.

The study aimed at improving the nutritional profile of yeast leavened salt reduced sliced bread and puccia type bread fortified with a wheat-based Lactobacillus plantarum ITM21B fermentation product (Bio21B). The protein content of bread made under laboratory conditions was increased by using: (i) chickpea flour (CF) (15% wt/wt flour) and Bio21B or (ii) the Bio21B containing a fungal protease to favour the gluten hydrolysis. Products showed increased protein and total amino acid content and improved protein digestibility. Moreover, the formula significantly affected the protein pattern of breads which, according to the results of the microfluidic two-dimensional electrophoresis (µ2DE) protein pattern, were discriminated as observed by the PCA plot. The use of CF was validated at industrial pilot plant producing salt reduced sliced bread and puccia type bread. The resulting products showed improved nutritional profile and a sensory quality comparable to the company's products containing salt.

Quality of ready-to-eat swordfish fillets inoculated with Lactobacillus paracasei IMPC 2.1.

BACKGROUND: The quality of marinated ready-to-eat (RTE) swordfish fillets, with or without inoculation with the probiotic strain Lactobacillus paracasei IMPC 2.1, was assessed over 3 months of refrigerated storage at 4 °C. RTE probiotic and control fish fillets were sampled after 7, 14, 30, 60, and 90 days of storage. Microbiological tests were performed, and fatty acid (FA) profiles and malondialdehyde content were examined. Microbiological counts, including total viable count, lactic acid bacteria (LAB), yeasts, moulds, Enterobacteriaceae, and Pseudomonadaceae were determined. RESULTS: Inoculation successfully ensured the growth of the probiotic strain and prevented the growth of other LAB. The two RTE products showed significant differences in lipid profile and lipid oxidation during storage. In particular, inoculation with L. paracasei IMPC 2.1 increased the amount of polyunsaturated FAs and limited the amount of monounsaturated FAs and oleic acid, as well as lipid oxidation. It thus represents an interesting strategy for preserving the chemical quality of fish fillets and an alternative means of delivering probiotics. CONCLUSION: Probiotic inoculation with Lactobacillus paracasei seemed to delay lipid oxidation of the fish flesh and increase the retention of polyunsaturated FAs, suggesting a potential application for this strain in the seafood industry. © 2018 Society of Chemical Industry.

Lactobacillus plantarum 5BG Survives During Refrigerated Storage Bio-Preserving Packaged Spanish-Style Table Olives (cv. Bella di Cerignola).

This paper proposes bio-preservation as a tool to assure quality and safety of Spanish-style table olives cv. Bella di Cerignola. Lactobacillus plantarum 5BG was inoculated in ready to sell olives packaged in an industrial plant by using a half-volume brine (4% NaCl; 2% sucrose). The samples were stored at 4°C. The survival of the inoculated strain, the microbiological quality, the sensory scores and the survival of a strain of Listeria monocytogenes inoculated in brines were evaluated. The persistence of the Lb. plantarum bio-preserving culture was confirmed on olives (≥6.5 Log CFU/g) and in brine (≥7 Log CFU/ml). Bio-preserved olives (SET1) showed a better sensory profile than chemically acidified control olives (SET2) and the texture was the real discriminative parameter among samples. Bio-preserved olives recorded better scores during storage because of their ability to retain good hardness, crunchiness, and fibrousness without cracks. The inoculation of Lb. plantarum positively acted on the safety of olives, as the D-value of L. monocytogenes was reduced from 40 (SET2) to 5 days (SET1). In conclusion, Lb. plantarum 5BG and the physico-chemical conditions achieved in the settled procedure are suitable for the industrial packaging of Bella di Cerignola table olives, improving the process by halving brining volumes and avoiding chemical stabilizers, and significantly reducing the salt concentration. The final product is also safely preserved for almost 5 months as suggested by the reduction of the survival rate of L. monocytogenes.

Effect of pH and TPP concentration on chemico-physical properties, release kinetics and antifungal activity of Chitosan-TPP-Ungeremine microbeads.

In this study, chitosan based microbeads containing Ungeremine, an antimicrobial alkaloid particularly active against Penicillium roqueforti, a filamentous fungus responsible of the bakery products deterioration, were prepared by external gelation by using sodium tripolyphosphate (TPP) as crosslinking agent. The stability of the beads, as well as the loading efficiency of the bioactive molecule, were assessed at different pH and TPP concentrations resulting particularly enhanced at low pH. All the microbeads evidenced antimicrobial activity against Penicillium roqueforti. The release kinetics of Ungeremine was tailored by opportunely modulating pH and TPP concentrations. Morphological analysis evidenced the improvement of the structural crosslinking density of microbeads including Ungeremine and spectroscopic analysis emphasized the active participation of Ungeremine to the crosslinking process occurring between chitosan and TPP. Finally, thermogravimetric analysis confirmed the increasing of free volume in three-dimensional networks and their liability to thermal degradation.