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1.
J Appl Microbiol ; 133(2): 1078-1088, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35611609

RESUMO

AIMS: Bacillus cereus is often responsible for foodborne diseases and both local and systemic infections in humans. Cases of infection in other mammals are rather rare. In this study, we report a B. cereus feed-related outbreak that caused the death of 6234 pigs in Italy. METHODS AND RESULTS: Massive doses of a Gram-positive, spore-forming bacterium were recovered from the animal feed, faeces of survived pigs and intestinal content of dead ones. The B. cereus MM1 strain was identified by MALDI-TOF MS and typified by RAPD-PCR. The isolate was tested for the production of PC-PLC, proteases, hemolysins and biofilm, for motility, as well as for the presence of genes encoding tissue-degrading enzymes and toxins. Antimicrobial resistance and pathogenicity in Galleria mellonella larvae were also investigated. Our results show that the isolated B. cereus strain is swimming-proficient, produces PC-PLC, proteases, hemolysins, biofilm and carries many virulence genes. The strain shows high pathogenicity in G. mellonella larvae. CONCLUSIONS: The isolated B. cereus strain demonstrates an aggressive profile of pathogenicity and virulence, being able to produce a wide range of determinants potentially hazardous to pigs' health. SIGNIFICANCE AND IMPACT OF STUDY: This study highlights the proficiency of B. cereus to behave as a devastating pathogen in swine if ingested at high doses and underlines that more stringent quality controls are needed for livestock feeds and supplements.


Assuntos
Ração Animal , Bacillus cereus , Infecções por Bactérias Gram-Positivas , Proteínas Hemolisinas , Ração Animal/microbiologia , Animais , Bacillus cereus/genética , Bacillus cereus/patogenicidade , Surtos de Doenças , Bactérias Gram-Positivas , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Proteínas Hemolisinas/genética , Larva/microbiologia , Mariposas/microbiologia , Peptídeo Hidrolases , Técnica de Amplificação ao Acaso de DNA Polimórfico , Esporos Bacterianos , Suínos
2.
BMC Vet Res ; 16(1): 65, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32085758

RESUMO

BACKGROUND: The presence of Anisakis larvae in fish represents a major public health concern. Effective risk management procedures should be applied to prevent heavily infected products from reaching the market. The aim of the study is to provide preliminary data on parasite exposure and risk classification in frozen fish products by applying a risk categorization scheme (site, abundance, density and epidemiology - SADE) and Fish Parasite Rating (FPR) method. Fish and cephalopods samples (N = 771) from 5 different FAO Atlantic areas were examined and categorized after an accurate visual inspection and a chloro-peptic digestion. RESULTS: In 25 out of 33 fish species parasite larvae were found. 10897 anisakids larvae were collected and identified to genus level. Molva dypterygia, Conger conger, Zeus faber and Aphanopus carbo were shown to be the most highly infected species. SADE and FPR scores were 1 and poor, respectively, for the referred species, because of the disseminated Anisakis infection and commercial rejection. CONCLUSION: SADE/FPR method showed high specificity and accuracy. The information provided in this work could be used in early warning systems for the detection of parasites in fishery products and might help fishing industries in establishing management strategies for infected stocks in terms of cost saving decisions.


Assuntos
Anisaquíase/epidemiologia , Doenças dos Peixes/parasitologia , Produtos Pesqueiros/parasitologia , Animais , Anisakis/classificação , Anisakis/genética , Anisakis/isolamento & purificação , Oceano Atlântico , Cefalópodes/parasitologia , Peixes , Parasitologia de Alimentos/estatística & dados numéricos , Larva , Reação em Cadeia da Polimerase/métodos
3.
J Dairy Sci ; 103(1): 150-160, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31668441

RESUMO

This study aimed to evaluate the possible inhibitory effect of natural lactic acid bacteria on the growth of 2 Bacillus cereus strains. First, we evaluated the behavior of spores of B. cereus GPe2 and D43 when inoculated before cheesemaking using pasteurized or raw milk; no statistical differences were observed between cheese produced with the 2 types of milk. Then, lactic acid bacteria (LAB) were isolated from cheese at the last sampling time, identified, and tested in vitro for their antagonistic activity and organic acid production by using an HPLC method, showing antimicrobial potential. The LAB that produced larger inhibition halos (>9 mm) against B. cereus strains (LAB 3, 6, 9, 10: Lactococcus lactis ssp. lactis; LAB 7: Lactococcus lactis ssp. cremoris) were selected to produce a LAB mixture for subsequent tests. Spores of B. cereus GPe2 and D43 were inoculated in pasteurized milk before cheesemaking with or without addition of the LAB mixture at a high dosage. Bacillus cereus grew more slowly when LAB were added to the dairy matrix (with differences from 2.36 to 2.66 log cfu/g in B. cereus GPe2 and D43 growth).


Assuntos
Bacillus cereus/crescimento & desenvolvimento , Queijo/microbiologia , Microbiologia de Alimentos , Lactobacillales/fisiologia , Lactococcus lactis/fisiologia , Leite/microbiologia , Animais , Ácidos Carboxílicos
4.
Food Microbiol ; 78: 123-133, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30497594

RESUMO

Challenge tests with eight brands of fresh ricotta showed rapid growth of Listeria monocytogenes and significant variability in physical-chemical characteristics. Thus, two cardinal parameters models were developed for the growth of L. monocytogenes in ricotta including, respectively, terms for temperature (Model 1) and temperature and pH (Model 2). Also an extensive, existing growth model including the effect of organic acids (Model 3) was product recalibrated to predict growth of L. monocytogenes in ricotta. Interestingly, a lack of anti-listerial effect of organic acids in ricotta was observed in this study. The range of applicability of Models 1 and 2 in ricotta (characterized by absence of competitive microbiota) included storage at temperatures from 4.1 to 20.6 °C, pH from 5.5 to 6.6, moisture contents from 72% to 82%, NaCl from 0.38% to 0.60%, concentrations of acetic acid from 579 to 1559 ppm in the water phase, citric acid from 14,774 to 46,116 ppm in the water phase, and lactic acid from 0 to 4146 ppm in the water phase. Comparing observed and predicted maximum specific growth rates of L. monocytogenes in ricotta showed a bias-factor significantly above 1, for existing models developed for broth and these models were thus fail-safe with predicted growth being faster than observed, while typically below 1 for models developed for other food types. The models developed in the present study showed bias-factors of 1.10, 1.06 and 0.78, respectively, for Model 1, 2, and 3. In particular, Model 1 and 2 developed and successfully validated could allow an easy determination of safe shelf-life of ricotta and facilitated the reformulation the product with the aim to increase shelf-life or safety.


Assuntos
Queijo/microbiologia , Listeria monocytogenes/crescimento & desenvolvimento , Temperatura , Contagem de Colônia Microbiana , Microbiologia de Alimentos/métodos , Inocuidade dos Alimentos/métodos , Armazenamento de Alimentos/métodos , Concentração de Íons de Hidrogênio , Cinética , Modelos Biológicos
5.
J Food Sci Technol ; 56(12): 5538-5543, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31749502

RESUMO

This study aimed to evaluate the effect of wet ageing on chemical-physical characteristics of sirloin and bone-in rib eye steaks obtained from 18 months old young bulls and 27 months old heifers. A positive beef tenderization effect of wet ageing was observed with lower values constantly detected in the rib-eye samples and significantly lower shear force values showed in heifer steaks if compared to bulls. The pH values detected both in pre- and post-ageing samples fell in the normal range for meats. The water holding capacity of sirloin samples increased with ageing while in rib eye steaks, no significant differences were detected among samples taken before and after ageing. Meat ageing resulted in a decrease of cooking loss, while meat colour parameters were not influenced by ageing and fell within the normal range. An evident improvement of the sensorial quality of bone-in wet aged beef, especially in tenderness, was achieved.

6.
Crit Rev Food Sci Nutr ; 58(7): 1131-1151, 2018 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27791395

RESUMO

OBJECTIVE: The aim of this study was to assess the mean of histamine concentration in food poisoning. DESIGN: Systematic review and meta-analysis of reports published between 1959 and 2013. STUDY SELECTION: Main criteria for inclusion of studies were: all report types that present outbreaks of "histamine poisoning' or "scombroid syndrome" from food, including histamine content and type of food. Health status of people involved must be nonpathological. RESULTS: Fifty-five (55) reports were included, these studies reported 103 incidents. All pooled analyses were based on random effect model; histamine mean concentration in poisoning samples was 1107.21 mg/kg with confidence interval for the meta-mean of 422.62-2900.78 mg/kg; heterogeneity index (I2) was 100% (P < 0.0001); prediction interval was 24.12-50822.78 mg/kg. Fish involved in histamine poisoning was mainly tuna or Istiophoridae species. No clues of association between concomitant conditions (female sex, alcohol consumption, previous medication, and consumption of histamine releasing food) and histamine poisoning, were highlighted. CONCLUSIONS: This is the first systematic review and meta-analysis that analyzes all the available data on histamine poisoning outbreaks evaluating the histamine concentration in food involved. Histamine mean concentration in poisoning samples was fairly high. Our study suffers from some limitations, which are intrinsic of the studies included, for instance the lack of a complete anamnesis of each poisoning episode. Protocol registration: Methods were specified in advance and have been published as a protocol in PROSPERO database (18/07/2012 -CRD42012002566).


Assuntos
Peixes , Contaminação de Alimentos , Doenças Transmitidas por Alimentos , Histamina/toxicidade , Animais , Humanos , Toxinas Marinhas/análise
7.
J Sci Food Agric ; 98(6): 2437-2439, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28981165

RESUMO

BACKGROUND: Animal food species identification by DNA sequencing has been increasing in recent years. During the last 10 years our species identification laboratory (LIS) produced nearly 1500 sequences from DNA of food species by means of polymerase chain reaction product sequencing. In this paper we desire to make public the LIS output of the last 10 years; that is, summarizing food species authentication projects that yielded good-quality (i.e. provided by Genbank accession number) DNA sequences. RESULTS: Thirteen project clusters yielded n = 705 sequences with accession number. CONCLUSION: The most relevant characteristics from the aforementioned project clusters were summarized. © 2017 Society of Chemical Industry.


Assuntos
DNA/genética , Análise de Alimentos , Contaminação de Alimentos/análise , Animais , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
8.
Crit Rev Food Sci Nutr ; 56(9): 1405-16, 2016 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-25807208

RESUMO

OBJECTIVE: To assess the prevalence and mean intensity of anisakids in seafood caught in the Mediterranean Sea, focusing on fish species at risk of being raw-consumed. DESIGN: Systematic review and meta-analysis of studies published from 1960-2012. STUDY SELECTION: Main criteria for the inclusion of studies were as follows: Findings of anisakid larvae, in both muscles and viscera; fish species for human consumption caught in the Mediterranean Sea; prevalence and mean intensity data for each species; and sample size equal to or more than 40 fishes. RESULTS: Twelve studies were identified. Among these, four studies considered the following three fish species that are often consumed raw or preserved lightly, or not cooked thoroughly: anchovy, pilchard, and Atlantic mackerel. DATA SYNTHESIS: All pooled analyses were based on the random-effect model. Anisakids prevalence in fish muscle was 0.64% (P < 0.0001), in viscera it was 1.34% (P < 0.0001), and overall prevalence was 0.95% (P < 0.0001). Mean intensity in muscle was 2.31 (P = 0.0083), in viscera it was 1.55 (P = 0.0174), and overall it was 1.81 (P < 0.0005). Heterogeneity indices (I(2)) were significantly high with the exception of viscera mean intensity. CONCLUSIONS: Anchovy, pilchard, and Atlantic mackerel have a low prevalence and mean intensity of anisakidae larvae in both viscera and muscles. Mean Intensity was also low.


Assuntos
Anisakis/isolamento & purificação , Peixes/parasitologia , Alimentos Marinhos/parasitologia , Animais , Anisaquíase/etiologia , Manipulação de Alimentos/métodos , Temperatura Alta , Humanos , Larva , Mar Mediterrâneo , Músculos/parasitologia , Especificidade da Espécie , Vísceras/parasitologia
9.
Sensors (Basel) ; 16(10)2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27775658

RESUMO

The development of a monitoring system to identify the presence of laying hens, in a closed room of a free-range commercial organic egg production farm, was the aim of this study. This monitoring system was based on the infrared (IR) technology and had, as final target, a possible reduction of atmospheric ammonia levels and bacterial load. Tests were carried out for three weeks and involved 7 ISA (Institut de Sélection Animale) brown laying hens. The first 5 days was used to set up the detection sensor, while the other 15 days were used to evaluate the accuracy of the resulting monitoring system, in terms of sensitivity and specificity. The setup procedure included the evaluation of different color background (CB) thresholds, used to discriminate the information contents of the thermographic images. At the end of this procedure, a CB threshold equal to an increase of 3 °C from the floor temperature was chosen, and a cutoff level of 196 colored pixels was identified as the threshold to use to classify a positive case. The results of field tests showed that the developed monitoring system reached a fine detection accuracy (sensitivity = 97.9% and specificity = 94.9%) and the IR technology proved to be a possible solution for the development of a detection sensor necessary to reach the scope of this study.


Assuntos
Técnicas Biossensoriais/métodos , Ovos , Espectrofotometria Infravermelho/métodos , Criação de Animais Domésticos/instrumentação , Criação de Animais Domésticos/métodos , Animais , Galinhas , Fazendas , Feminino
10.
Heliyon ; 10(10): e30883, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38765030

RESUMO

In the present study, growth potential of Listeria monocytogenes in steak tartare samples taken at retail and belonging to 13 brands marketed in Northern Italy was investigated. The samples were submitted to microbiological and chemical-physical characterization. The data obtained were used as inputs for the application of the predictive microbiology software FSSP that allows the estimation of the growth of L. monocytogenes during the shelf-life. Lactic acid bacteria, the main component of the microflora, gave variable counts among the brands (from 3.38 to 6.24 log CFU/g). pH and aw values were always higher than 5.3 and 0.96, respectively, thus they could not be considered as single efficient hurdles to prevent the growth of L. monocytogenes according to the EC Reg. 2073/2005; the same was observed for salt content (constantly <2 %) and nitrites (not quantifiable in all the samples, even if declared in some labels). Nevertheless, the combination of all the hurdles, evaluated by predictive microbiology using critical development factors, resulted in an estimated growth <0.5 log CFU/g throughout the shelf life; this output allowed us to consider all the steak tartare analysed as unfavourable substrate for L. monocytogenes growth. The information obtained could be useful for tartare producers as well as for competent authority to evaluate the effective risk concerning these typology of products.

11.
Microorganisms ; 12(6)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38930557

RESUMO

Cooked sausages packaged in a modified atmosphere (MAP: 20% CO2, 70% N2, <0.2% O2) with evident yellow stains were analyzed. The aims of this work were to study the microbial cause of the spoilage and to evaluate different antimicrobial compounds to prevent it. Leuconostoc gelidum was identified as the primary cause of the yellow coating in spoiled cooked sausage, as confirmed by its intentional inoculation on slices of unspoiled sausage. Leuconostoc gelidum was the main bacteria responsible for the yellow coating in spoiled cooked sausage, as confirmed by its intentional inoculation on slices of unspoiled sausage. The yellow color was also evident during growth in the model system containing cooked sausage extract, but the colonies on MRS agar appeared white, demonstrating that the food substrate stimulated the production of the yellow pigment. The spoilage was also characterized by different volatile compounds, including ketones, ethanol, acetic acid, and ethyl acetate, found in the spoiled cooked sausage packages. These compounds explained the activity of Leuc. gelidum because they are typical of heterofermentative LAB, cultivated either on food substrates or in artificial broths. Leuc. gelidum also produced slight swelling in the spoiled packages. The efficacy of different antimicrobials was assessed in model systems composed of cooked sausage extract with the antimicrobials added at food product concentrations. The data showed that sodium lactate, sodium acetate, and a combination of sodium lactate and sodium diacetate could only slow the growth of the spoiler-they could not stop it from occurring. Conversely, hop extract inhibited Leuc. gelidum, showing a minimal inhibitory concentration (MIC) of approximately 0.008 mg CAE/mL in synthetic broth and 4 mg CAE/kg in cooked sausage slices. Adding hop extract at the MIC did not allow Leuc. gelidum growth and did not change the sensorial characteristics of the cooked sausages. To our knowledge, this is the first report of the antimicrobial activities of hop extracts against Leuc. gelidum either in vitro or in vivo.

12.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38490265

RESUMO

This study investigated the effects of salty and sugary former foodstuff products (FFPs) on the quality traits and meat composition of 36 male castrated pigs (Swiss Large White breed) as well as sensory characteristics of the loins. The animals were fed three different diets for both the growing (G) and finishing (F) phases: (1) a standard diet (ST), 0% FFPs; (2) a diet with 30% of sugary FFPs (e.g., chocolate, biscuits, cakes) as a replacement for traditional ingredients (SU); and (3) a diet with 30% of salty FFPs (e.g., bread, pasta, and breadsticks) as a replacement for traditional ingredients (SA). For a comprehensive assessment of meat quality, protein and fat content in the LD were analyzed. AA and FA profile were determined both in the LD and backfat. Meat quality traits such as pH and temperature, thawing, cooking and drip losses, and shear force have been evaluated. Then, pork loins have been assessed for sensory attributes by a trained sensory panel. The SA diet decreased 20:5 n-3 levels (P < 0.001) in the muscle and 22:5 n-3 levels (P < 0.05) in both muscle and backfat but increased (P < 0.05) the ratio of mono-unsaturated to saturated fatty acids compared to the ST group. Both the SU and SA diets elevated (P < 0.001) the n-6:n-3 fatty acids ratio compared to the ST diet. Dietary treatments did not affect other meat quality traits. Regarding sensory attributes, the loin from pigs fed with SU and SA diets were sweeter (P < 0.001). Loins of SA pigs were more tender (P < 0.001), had a more intense pork aroma (P < 0.001) and had more flavor (P < 0.01) compared to ST loins. Overall, the use of FFPs affected the fatty acid profile of pork while improving the sensory quality of the loins, with no negative effects observed on the technological and nutritional quality of the meat.


Pigs are ideal species to convert food losses, also named former food products (FFPs), into animal proteins. The present study investigated the impact of incorporating sugary and salty FFPs into the diets of growing and finishing pigs on meat quality and its sensory characteristics. Our study showed that, while technological meat quality remained largely unaffected, the dietary treatments led to slight alterations of meat and backfat fatty acids profile. Moreover, a panel test for sensory analyses revealed that loins from both the sugary and salty ingredients-fed pigs were perceived as sweeter, and loins from pigs fed salty ingredients were noted for increased tenderness, intense pork aroma, and flavor. Overall, FFPs inclusion into pig diets had no detrimental effects on technological or nutritional aspects of the meat, confirming their potential use as alternative animal feed.


Assuntos
Composição Corporal , Melhoramento Vegetal , Suínos , Masculino , Animais , Dieta/veterinária , Carne , Ácidos Graxos/metabolismo , Músculo Esquelético/metabolismo , Ração Animal/análise
13.
Ital J Food Saf ; 12(2): 11087, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37405141

RESUMO

The aim of this study was to evaluate the shelf-life of pre-packaged sheep's arrosticini produced in a factory located in northern Italy. Samples were divided into two series and packaged in modified atmosphere with specific gas mixtures: conventional (C: 35% O2/15% CO2/50% N2) and experimental (E: 30% CO2/70% N2). All the samples were stored at 4°C for 10 days and subjected, after 5, 8 and 10 days (t5, t8, t10), to triplicate microbiological and chemical- physical (pH, total volatile basic nitrogen, thiobarbituric acid reactive substances) analyses. At the same time, the colorimetric analysis and a sensorial evaluation were carried out (pack tightness, presence of color or odor alterations), assigning a discrete score from 0 to 5. The samples showed initial total bacterial counts close to 5 Log CFU/g: these values gradually increased during storage, exceeding the threshold of 8 Log CFU/g in the C series; lower values were detected in the E series. A similar trend was highlighted for Enterobacteriaceae, with initial loads of about 3 Log CFU/g and an increase until t10, reaching values higher than 6 Log CFU/g in the C series and close to 5 Log CFU/g in the E series (P=0.002). E. coli also showed a similar trend, although with values approximately 1 Log lower than Enterobacteriaceae. Pseudomonas spp. showed initial counts close to 4.5 Log CFU/g, with a different increase in the C series (6.5 Log CFU/g at t10) and the E series (4.95 Log CFU/g) (P= 0.006). The higher growth in the C series was also observed for lactic acid bacteria, with an increase from 3 to 5 Log CFU/g (3.8 Log CFU/g in the E series P=0.016). The other microbiological parameters showed very low counts and, in most cases undetectable counts (<2 Log CFU/g) for the entire period considered. The initial values obtained from the measurement of the colorimetric indices were within the norm for this type of product: however, starting from t5, lower values of red index and lightness in the E series were measured, with an evident greying of meat surface. The results of the sensory evaluation indicated that the product showed optimal sensorial characteristics up to 8 days of shelf-life in the C series, while the use of an oxygenfree atmosphere, despite having a moderate inhibiting effect on the microbial populations, has led to an early modification of the product (5 days of storage), due to the presence of superficial greyish areas. The microbiological characteristics of arrosticini strictly depend on the hygienic conditions of slaughtering and production; even in optimal situations, the product is particularly perishable, and requires careful management of storage temperatures and times, to maintain its quality characteristics.

14.
Nat Prod Res ; 37(16): 2742-2747, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36134545

RESUMO

Chemical composition and in vitro antimicrobial activity of parsley [Petroselinum crispum (Mill.) Fuss] and ginger (Zingiber officinale Roscoe) essential oils from store-bought parsley plants and ginger rhizomes were evaluated. A sensory analysis was performed on aged cheese slices treated with a mix of each essential oil and seed oil. Parsley essential oil was selected as the best compromise between sensory influence and antimicrobial activity and tested to evaluate its antifungal effects on cheese slices experimentally contaminated with Aspergillus flavus. Monoterpenes and α-zingiberene were the most abundant compounds in parsley and ginger essential oil, respectively. Both essential oils showed in vitro antimicrobial activity against different fungal species while only a bacterial strain (Enterococcus faecalis) was sensible to ginger essential oil. Only the cheese slices treated with parsley essential oil were appreciated by the panellists and its use has been effective in preventing the A. flavus growth in cheese.

15.
Microorganisms ; 11(2)2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36838486

RESUMO

This study investigated B. cereus presence in 122 samples belonging to 34 typologies of fresh or short-ripened cheeses made from cow, sheep, goat, or buffalo pasteurized milk, and sold on the Italian market. B. cereus was isolated at a prevalence of 9.8%, with a marked variability among cheese categories, and at low counts (always below 2.26 Log CFU/g). Twelve isolates were identified by MALDI-TOF analysis and typified by RAPD PCR as belonging to different B. cereus strains. All the strains were tested for the production of hemolysin BL, phosphatidylcholine-specific phospholipase C, proteases, and biofilm formation, and for the presence of chromosomal toxin-encoding genes (sph, plcA, cytK, entFM, bcet, nheA, nheB, nheC). Overall, 92% of strains harbored bcet, 75% the three genes nheA, nheB, and nheC, as well as plcA and sph, 67% entFM, and 33% cytK. All strains showed biofilm-forming ability. A chemical-physical characterization of the cheeses was also performed to show their suitability as substrates for B. cereus growth, showing high heterogeneity in terms of pH, aw, salt content, and concentration of organic acids. Finally, the ability to support spore germination and vegetative cell growth of a selected cheese was investigated in spores-inoculated samples maintained at 10 °C and 15 °C, showing the inhibitory effect of low storage temperatures.

16.
Microorganisms ; 11(8)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37630502

RESUMO

Recently, during the ripening of goose sausage, a defect consisting of ammonia and vinegar smell was noticed. The producer of the craft facility, located in Lombardia, a Northern region of Italy, asked us to identify the cause of that defect. Therefore, this study aimed to identify the potential responsible agents for the spoilage of this lot of goose sausages. Spoilage was first detected by sensory analysis using the "needle probing" technique; however, the spoiled sausages were not marketable due to the high ammonia and vinegar smell. The added starter culture did not limit or inhibit the spoilage microorganisms, which were represented by Levilactobacillus brevis, the predominant species, and by Enterococcus faecalis and E. faecium. These microorganisms grew during ripening and produced a large amount of biogenic amines, which could represent a risk for consumers. Furthermore, Lev. brevis, being a heterofermentative lactic acid bacteria (LAB), also produced ethanol, acetic acid, and a variation in the sausage colour. The production of biogenic amines was confirmed in vitro. Furthermore, as observed in a previous study, the second cause of spoilage can be attributed to moulds which grew during ripening; both the isolated strains, Penicillium nalgiovense, added as a starter culture, and P. lanosocoeruleum, present as an environmental contaminant, grew between the meat and casing, producing a large amount of total volatile nitrogen, responsible for the ammonia smell perceived in the ripening area and in the sausages. This is the first description of Levilactobacillus brevis predominance in spoiled goose sausage.

17.
J Hazard Mater ; 448: 130888, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36746085

RESUMO

Food waste and feed-food competition can be reduced by replacing traditional feed ingredients such as cereals, with former food products (FFPs) in livestock diets. These foodstuffs, initially intended for human consumption, are recovered, mechanically unpacked, and then ground. Despite this simple and inexpensive treatment, packaging contaminants (remnants) are often unavoidable in the final product. To maximize the exploitation of FFPs and to minimize the associated risks, packaging remnants need to be quantified and characterized. This study tested the efficacy of the Fourier Transform Infrared Spectroscopy coupled with an optical microscope (µFT-IR) in identifying packaging remnants in 17 FFP samples collected in different geographical areas. After a visual sorting procedure, presumed packaging remnants were analyzed by µFT-IR. The results showed significant differences (p < 0.05) between the FFPs in terms of the total number of foreign particles found (plastics, cellulose and aluminum remnants, ranging from 4 to 19 particles per 20 g fresh matter), and also regarding the number of cellulose and aluminum particles. These data clearly demonstrate the need for sensitive instruments that can characterize the potential contaminants in the FFPs. This would then help to reduce the overestimation of undesirable contaminants typical of simple visual sorting, which is currently the most common method.


Assuntos
Alimentos , Eliminação de Resíduos , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier , Alumínio , Plásticos , Celulose
18.
Foods ; 12(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37509776

RESUMO

The aim of this study was to investigate the microbial and physico-chemical characteristics of cold smoked sea bass (CSSB), a novel italian fish product. The microbiological analyses showed the presence of bacterial contamination from the raw material, the environment, and the production process. The microbial spoilage population was dominated by lactic acid bacteria (LAB) associated with Gram-negative fermenting bacteria, including Photobacterium phosphoreum and psychrotrophic Enterobacteriaceae. Brochotrix thermospacta and Aeromonas spp. were also present; in contrast, mould and yeast were not detected (<2 CFU/g). High levels (6-7 log CFU/g) of LAB and total bacteria count (TBC) were observed from day 45 of storage; however, their presence does not seem to have influenced the total volatile basic nitrogen (TVB-N), which always remained below 35 mg N/100 g. Consequently, the product is acceptable until day 60 of storage, considering that the malonaldehyde index (TBARS) was lower than 6.5 nmol/g. Pathogenic bacteria such as Salmonella spp. and Listeria monocytogenes were not detected. Currently, there is a growing demand for seafood due to its high quality and nutritional value. Cold smoked sea bass offers a source of macro- and micronutrients essential for the proper functioning of the human body. It is also rich in protein and omega-3 fatty acids. The WHO and FAO evaluated the benefits and risks and concluded that there is convincing evidence of health benefits from fish consumption, such as a reduction in the risk of heart failure and improved neurodevelopment in infants and young children when fish is consumed by the mother before and during pregnancy. The CSSB analysed in this study demonstrated to have health benefits due to long-chain omega-3 PUFAs and other nutrients, such as proteins, minerals, and vitamin D, which are sometimes difficult to obtain from other sources. The results show that CSSB has a high nutritional value and excellent microbial quality.

19.
Toxins (Basel) ; 15(3)2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36977059

RESUMO

Aflatoxins (AFs) are fungal metabolites that are found in feed and food. When ruminants eat feed contaminated with aflatoxin B1 (AFB1), it is metabolised and aflatoxin M1 (AFM1) is excreted in the milk. Aflatoxins can result in hepatotoxic, carcinogenic, and immunosuppressive effects. The European Union thus set a low threshold limit (50 ng/L) for presence of AFM1 in milk. This was in view of its possible presence also in dairy products and that quantification of these toxins is mandatory for milk suppliers. In the present study, a total of 95,882 samples of whole raw milk, collected in northern Italy between 2013 and 2021, were evaluated for presence of AFM1 using an ELISA (enzyme-linked immunosorbent assay) method. The study also evaluated the relationship between feed materials collected from the same farms in the same area during the same period (2013-2021) and milk contamination. Only 667 milk samples out of 95,882 samples analysed (0.7%) showed AFM1 values higher than the EU threshold limit of 50 ng/L. A total of 390 samples (0.4%) showed values between 40 and 50 ng/L, thus requiring corrective action despite not surpassing the regulatory threshold. Combining feed contamination and milk contamination data, some feedingstuffs seem to be more effective in defying potential carryover of AFs from feed to milk. Combining the results, it can be concluded that a robust monitoring system that covers both feed, with a special focus on high risk/sentinel matrices, and milk is essential to guarantee high quality and safety standards of dairy products.


Assuntos
Aflatoxina M1 , Aflatoxinas , Animais , Aflatoxina M1/análise , Aflatoxina B1/análise , Leite/química , Ração Animal/análise , Contaminação de Alimentos/análise , Aflatoxinas/análise , Itália
20.
Ital J Food Saf ; 11(1): 10034, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35284340

RESUMO

In this study the influence of the maintenance of beef (Bavarian heifer meat submitted to dry aging for 1 month) in purified sea water was evaluated considering microbiological and physical-chemical parameters. The treated samples were perforated on their upper and lower surfaces, subsequently placed in sterile plastic containers, and covered with purified sea water while the control samples were wrapped in a plastic film; all the samples were stored at 2°C and sample analyses were performed on the day of receipt (t0) and after five (t5), seven (t7) and ten (t10) days of storage. The initial bacterial population was close to 6 log CFU/g, as expected in meat subjected to a long ageing. After 5 and 10 days of storage the treated samples showed significantly lower counts for most parameters (Total Bacterial Count, Enterobacteriaceae, Lactic Acid Bacteria and Pseudomonas spp.) if compared to the control samples. Halotolerant bacteria, yeasts and moulds showed no differences between the two series. During the test, the exposed surface of treated meat samples underwent a partial protein denaturation. Analyses show a moderate acidification of the meat during the first part of storage (from t0 to t5), followed by a substantial stabilization in the second part of the trial. The meat maintained in purified sea water acquired a significantly and constantly higher water retention due to the absorption of salt by the meat. No significant difference was detected in terms of tenderness between the two series.

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