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1.
Orphanet J Rare Dis ; 19(1): 148, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582886

RESUMO

BACKGROUND: Most patients suffering from Leber hereditary optic neuropathy carry one of the three classic pathologic mutations, but not all individuals with these genetic alterations develop the disease. There are different risk factors that modify the penetrance of these mutations. The remaining patients carry one of a set of very rare genetic variants and, it appears that, some of the risk factors that modify the penetrance of the classical pathologic mutations may also affect the phenotype of these other rare mutations. RESULTS: We describe a large family including 95 maternally related individuals, showing 30 patients with Leber hereditary optic neuropathy. The mutation responsible for the phenotype is a novel transition, m.3734A > G, in the mitochondrial gene encoding the ND1 subunit of respiratory complex I. Molecular-genetic, biochemical and cellular studies corroborate the pathogenicity of this genetic change. CONCLUSIONS: With the study of this family, we confirm that, also for this very rare mutation, sex and age are important factors modifying penetrance. Moreover, this pedigree offers an excellent opportunity to search for other genetic or environmental factors that additionally contribute to modify penetrance.


Assuntos
DNA Mitocondrial , Atrofia Óptica Hereditária de Leber , Humanos , DNA Mitocondrial/genética , Atrofia Óptica Hereditária de Leber/genética , Linhagem , Mutação/genética , Fenótipo
2.
Foods ; 13(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38540941

RESUMO

The aim of this study was to develop a plant-based fermented beverage from discarded bread flour and to analyze its characteristics as a novel functional product. Eight cereal-based probiotic beverages were produced by inoculating discarded bread flour with a monoculture of Lactobacillus rhamnosus or a co-culture consisting of lactic acid bacteria and Bifidobacterium. Two additional factors, namely, the addition of amylolytic enzymes and matrix desalting, were studied alongside the type of culture. The organic acid content and microbial growth were monitored during fermentation and storage (15 and 21 days). Proximal composition, gamma-aminobutyric acid, and volatile compounds were measured in the final product. Sensory analysis was only conducted on the enzymatically treated samples. The estimated shelf life of the bread beverage was 15 days. The variables studied significantly influenced the amountof organic acids and specific volatile compounds responsible for the aroma of fermented beverages. The beverage produced via co-culturing was preferred by consumers in the sensory test.

3.
Animals (Basel) ; 13(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38003083

RESUMO

Twenty-two Assaf male lambs (29.2 ± 0.9 kg live weight and 89 ± 0.2 days of age), distributed in two experimental groups, were used to evaluate the use of either feed-grade conventional urea (Control diet; n = 11) or slow-release urea (SRU diet; n = 11) as sources of dietary nitrogen on animal performance, ruminal fermentation, blood acid-base status, plasmatic metabolic profile, and carcass and meat quality. Animals were housed individually and fed ad libitum. At the end of the fattening period (day 70), the animals were slaughtered to compare the fermentation patterns in ruminal digesta and to evaluate the carcass and meat characteristics. No statistically significant differences (p > 0.05) were observed between treatments in the dry matter intake, final live weight, average daily gain, and feed conversion rate. Regarding the ruminal fermentation parameters, the molar proportion of propionic acid was higher (p < 0.05) and that of butyric acid was lower (p < 0.05) with the SRU than with the Control diet. There were no significant differences (p > 0.05) between experimental treatments in the blood acid-base status and biochemical profile, except for the concentration of urea in plasma, which was significantly (p < 0. 05) greater in SRU than in Control lambs. No statistically significant differences were observed between treatments (p > 0.05) in the carcass and meat characteristics. In conclusion, the use of slow-release urea as a replacement for feed-grade conventional urea in the diet of Assaf fattening lambs, under the experimental conditions of this study, did not improve animal performance and increased the feeding costs.

4.
Front Vet Sci ; 10: 1150996, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37255997

RESUMO

Introduction: Suckling lamb meat is highly appreciated in European Mediterranean countries because of its mild flavor and soft texture. In suckling lamb carcasses, perirenal and pelvic fat depots account for a large fraction of carcass fat accumulation, and their proportions are used as an indicator of carcass quality. Material and Methods: This study aimed to characterize the genetic mechanisms that regulate fat deposition in suckling lambs by evaluating the transcriptomic differences between Spanish Assaf lambs with significantly different proportions of kidney knob and channel fat (KKCF) depots in their carcasses (4 High-KKCF lambs vs. 4 Low-KKCF lambs). Results: The analyzed fat tissue showed overall dominant expression of white adipose tissue gene markers, although due to the young age of the animals (17-36 days), the expression of some brown adipose tissue gene markers (e.g., UCP1, CIDEA) was still identified. The transcriptomic comparison between the High-KKCF and Low-KKCF groups revealed a total of 80 differentially expressed genes (DEGs). The enrichment analysis of the 49 DEGs with increased expression levels in the Low-KKCF lambs identified significant terms linked to the biosynthesis of lipids and thermogenesis, which may be related to the higher expression of the UCP1 gene in this group. In contrast, the enrichment analysis of the 31 DEGs with increased expression in the High-KKCF lambs highlighted angiogenesis as a key biological process supported by the higher expression of some genes, such as VEGF-A and THBS1, which encode a major angiogenic factor and a large adhesive extracellular matrix glycoprotein, respectively. Discussion: The increased expression of sestrins, which are negative regulators of the mTOR complex, suggests that the preadipocyte differentiation stage is being inhibited in the High-KKCF group in favor of adipose tissue expansion, in which vasculogenesis is an essential process. All of these results suggest that the fat depots of the High-KKCF animals are in a later stage of development than those of the Low-KKCF lambs. Further genomic studies based on larger sample sizes and complementary analyses, such as the identification of polymorphisms in the DEGs, should be designed to confirm these results and achieve a deeper understanding of the genetic mechanisms underlying fat deposition in suckling lambs.

5.
Animals (Basel) ; 13(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36670801

RESUMO

Beef derived from grass-fed cattle is a specific quality criterion. The effect of grass silage intake on quality characteristics, i.e., fatty acids, fat-soluble vitamins, and lipid-derived volatile composition of intramuscular and perirenal fat from fattening bull weaners were studied. Visible (VIS) and near-infrared (NIR) spectra were also obtained from perirenal fat. Perirenal fat analysis was performed for feeding differentiation purposes. A total of 22 Tudanca breed 11-month-aged bulls were finished on three different diets: grass silage and a commercial concentrate ad libitum (GS-AC), grass silage ad libitum and the commercial concentrate restricted to half of the intake of the GS-AC group (GS-LC), and barley straw and concentrate ad libitum (Str-AC). Feeding had a significant effect (p < 0.05) on γ-linolenic acid and the ratio n-6/n-3 fatty acids. Furthermore, ß-carotene content was greater in beef from silage groups than in the Str-AC group. Feeding also affected the perirenal fat composition. Beef from silage-fed bulls and straw-fed bulls could be differentiated by fatty acid percentages, especially 18:0, t-18:1, and c9-18:1, ß-carotene content, b* colour value, and carotenoid colour index. However, the VIS or NIR spectra data showed poor differentiating performance, and the volatile composition did not have appreciable differentiation power.

6.
Foods ; 12(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38231830

RESUMO

This study involved a comprehensive examination of sensory attributes in dry-cured Bísaro loins, including odor, androsterone, scatol, lean color, fat color, hardness, juiciness, chewiness, flavor intensity and flavor persistence. An analysis of 40 samples revealed a wide variation in these attributes, ensuring a robust margin for multivariate calibration purposes. The respective near-infrared (NIR) spectra unveiled distinct peaks associated with significant components, such as proteins, lipids and water. Support vector regression (SVR) models were methodically calibrated for all sensory attributes, with optimal results using multiplicative scattering correction pre-treatment, MinMax normalization and the radial base kernel (non-linear SVR model). This process involved partitioning the data into calibration (67%) and prediction (33%) subsets using the SPXY algorithm. The model parameters were optimized via a hybrid algorithm based on particle swarm optimization (PSO) to effectively minimize the root-mean-square error (RMSECV) derived from five-fold cross-validation and ensure the attainment of optimal model performance and predictive accuracy. The predictive models exhibited acceptable results, characterized by R-squared values close to 1 (0.9616-0.9955) and low RMSE values (0.0400-0.1031). The prediction set's relative standard deviation (RSD) remained under 5%. Comparisons with prior research revealed significant improvements in prediction accuracy, particularly when considering attributes like pig meat aroma, hardness, fat color and flavor intensity. This research underscores the potential of advanced analytical techniques to improve the precision of sensory evaluations in food quality assessment. Such advancements have the potential to benefit both the research community and the meat industry by closely aligning their practices with consumer preferences and expectations.

7.
Foods ; 11(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36496624

RESUMO

Sodium chloride (NaCl) is a key ingredient in the processing of traditional dry-cured meat products by improving microbial safety, sensory attributes and technological properties. However, increasing concern about the consumption of sodium and health has been supporting the development of low-sodium meat products. Several strategies to reduce sodium in dry-cured meat product have been tested, although the followed approaches sometimes result in undesirable characteristics concerning flavor, texture and mouthfeel. The use of halophytic plants such as glasswort (Salicornia herbacea) in food matrices has been suggested as a novel strategy to reduce sodium content, due its salty flavor. The main aim of the present study is to produce traditional dry-cured pork bellies from the Bísaro breed using glasswort as a NaCl partial replacer, and compare it with dry-cured bellies salted either with NaCl or a mix of NaCl + KCl. Control bellies (BC) were salted with 100% of NaCl, the second formulation (BK) had 50% of NaCl and 50% of KCl, and the third formulation (BG) had 90% of NaCl and 10% of glasswort powder (GP). After production, the bellies were evaluated for aw, pH, CIELab coordinates, weight loss, proximal composition, TBARS, collagen and chloride contents, fatty acid profile and sensory attributes. The use of BG in dry-cured pork bellies did not affect processing indicators such as weight loss, aw and pH. Concerning CIELab, only the coordinates L* and hue angle from the external surface color of BG were statistically different from BC and BK. As expected, ash and NaCl contents differed from BG to the other two formulations. SFA and indexes AI and TI were lower, whereas the MUFA and h/H ratio were higher in BG than other treatments, leading to a product with a healthier lipid profile. The sensory evaluation revealed differences in appearance, taste and flavor among treatments, but did not indicate any negative effects of BG in the product attributes. This study reinforces the potential of BG as a natural sodium reducer for the production of traditional dry-cured pork bellies.

8.
Front Genet ; 13: 1035063, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386829

RESUMO

In sheep, differences were observed regarding fat accumulation and fatty acid (FA) composition between males and females, which may impact the quality and organoleptic characteristics of the meat. The integration of different omics technologies is a relevant approach for investigating biological and genetic mechanisms associated with complex traits. Here, the perirenal tissue of six male and six female Assaf suckling lambs was evaluated using RNA sequencing and whole-genome bisulfite sequencing (WGBS). A multiomic discriminant analysis using multiblock (s)PLS-DA allowed the identification of 314 genes and 627 differentially methylated regions (within these genes), which perfectly discriminate between males and females. These candidate genes overlapped with previously reported QTLs for carcass fat volume and percentage of different FAs in milk and meat from sheep. Additionally, differentially coexpressed (DcoExp) modules of genes between males (nine) and females (three) were identified that harbour 22 of these selected genes. Interestingly, these DcoExp were significantly correlated with fat percentage in different deposits (renal, pelvic, subcutaneous and intramuscular) and were associated with relevant biological processes for adipogenesis, adipocyte differentiation, fat volume and FA composition. Consequently, these genes may potentially impact adiposity and meat quality traits in a sex-specific manner, such as juiciness, tenderness and flavour.

9.
Biomolecules ; 12(10)2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36291625

RESUMO

Diversified strategies to incorporate healthier lipids in processed meat products are being developed. Alternative fat sources to replace animal fat associated with the reduction of fat content are some of the methods used to obtain healthier meat products well recognized by consumers. In order to create a healthier product that can also be consumed in the Halal and Kosher consumer markets, an experimental study was developed to assess the effects of replacing the pork fat (4%) with the same amount of hydrogel emulsion incorporating olive oil or sunflower oil. Three burgers were randomly selected from each lot manufactured and analyzed in triplicate. Burgers were physicochemical analyzed for pH, water activity, composition, fatty acid profile, color, yield, texture, oxidative stability, and volatile compounds and compared according to the fat source. Burgers with hydrogel emulsions can be considered reduced-fat meat products with a healthier fatty acid profile than pork fat burgers. The use of hydrogel emulsions did not negatively affect the quality characteristics assessed in the product and improved the oxidative stability during the storage of cooked burgers. By the characteristics and formulations evaluated, the replacement of pork fat with olive oil hydrogel emulsion proved to be the most effective strategy for obtaining a healthier goat meat product.


Assuntos
Produtos da Carne , Olea , Carne de Porco , Carne Vermelha , Animais , Suínos , Produtos da Carne/análise , Óleo de Girassol , Emulsões/química , Azeite de Oliva , Hidrogéis , Cabras , Óleos de Plantas/química , Ácidos Graxos , Água/química
11.
Graefes Arch Clin Exp Ophthalmol ; 260(10): 3173-3183, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35467125

RESUMO

PURPOSE: To analyze the recovery course of foveal microstructures in eyes with nonsurgical healing of full-thickness macular hole (FTMH). METHODS: By serial OCT scans, the temporal healing sequences were analyzed in ocular trauma, vitreomacular traction (VMT), cystoid macular edema (CME), and the remaining group. We evaluated correlations between the final best-corrected spectacle visual acuity and reconstruction time of external limiting membrane (ELM), and inner segment/outer segment (IS/OS). RESULTS: The healing (mean±standard deviation in months) most involved fusion at the level of the outer nuclear layer (ONL) (6.3±10.5) followed by restoration of ELM (9.1±13.8), and lastly, by IS/OS regeneration (13.1±19.5). In severe blunt ocular trauma, healing was fast and involved subretinal zipper glue-like reapposition with resulting outer retinal atrophy. Best spectacle-corrected visual acuity correlated with normalization of the clivus (p=0.012), faster ELM (p=0.006), and IS/OS reconstitution (p=0.024). Recurrence of FTMH occurred when the healing was halted (3 eyes) or was aberrant by lamellar hole epiretinal proliferation (LHEP) (3 eyes) or by the persistence of VMT (1 eye). CONCLUSION: Recovery sequences proceeded from the ONL to the deeper layers with BCVA correlating absolutely and temporally with the restoration of outer retinal layer integrity.


Assuntos
Perfurações Retinianas , Fóvea Central , Humanos , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/cirurgia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Transtornos da Visão , Acuidade Visual , Vitrectomia
12.
Br J Ophthalmol ; 106(10): 1463-1468, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33926863

RESUMO

PURPOSE: To ascertain the anatomic factors that help achieve non-surgical sealing in full thickness macular hole (FTMH). METHODS: Retrospective collaborative study of FTMH that closed without surgical intervention. RESULTS: A total of 78 patients (mean age 57.9 years) included 18 patients with blunt ocular trauma, 18 patients that received topical or intravitreal therapies and 42 patients with idiopathic FTMH. Mean±SD of the initial corrected visual acuity (VA) in logMAR improved from 0.65±0.54 to 0.34±0.45 (p<0.001) at a mean follow-up of 33.8±37.1 months. FTMH reopened in seven eyes (9.0%) after a mean of 8.6 months. Vitreomacular traction was noted in 12 eyes (15.8%), perifoveal posterior vitreous detachment in 42 (53.8%), foveal epiretinal membrane in 10 (12.8%), cystoid macular oedema (CME) in 49 (62.8%) and subretinal fluid (SRF) in 20 (25.6%). By multivariate analysis, initial VA correlated to the height (p<0.001) and narrowest diameter of the hole (p<0.001) while final VA correlated to the basal diameter (p<0.001). Time for closure of FTMH (median 2.8 months) correlated to the narrowest diameter (p<0.001) and the presence of SRF (p=0.001). Mean time for closure (in months) was 1.6 for eyes with trauma, 4.3 for eyes without trauma but with therapy for CME, 4.4 for eyes without trauma and without therapy in less than 200 µm in size and 24.7 for more than 200 µm. CONCLUSION: Our data suggest an observation period in new onset FTMH for non-surgical closure, in the setting of trauma, treatment of CME and size <200 µm.


Assuntos
Perfurações Retinianas , Ferimentos não Penetrantes , Fóvea Central , Humanos , Pessoa de Meia-Idade , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/cirurgia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual , Vitrectomia , Ferimentos não Penetrantes/diagnóstico , Ferimentos não Penetrantes/cirurgia
13.
Polymers (Basel) ; 13(19)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34641212

RESUMO

Large-core polymer optical fiber (POF) links have limitations in capacity and reach due to the fibers' high modal dispersion and attenuation. Most of these links use red laser diodes, even though the attenuation spectrum of poly(methyl methacrylate) (PMMA), the basic polymer used to manufacture these fibers, has a lower minimum in the green region. Therefore, we set out to explore the potential use of green light in transmission systems, comparing the performances of three step-index polymer optical fibers (SI-POFs) with different numerical apertures. We obtained measurements of intensity distribution, frequency response and bit error rate (BER), as functions of fiber length. We have also compared the fibers' frequency responses with red and green light for a few selected lengths. Our results confirm that SI-POFs attenuate less in response to green light, which can increase their length. This advantage is partially counterbalanced by a slightly higher dispersion that limits the capacity of the high-aperture fibers, particularly at relatively short lengths. Our conclusions are critical to understanding SI-POF behavior and to designing thorough SI-POF models that can aid the design of POF-based links for different scenarios.

14.
Foods ; 10(9)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34574283

RESUMO

Banana pseudo-stem (BPS), which is rich in fibre and polyphenols, is a potential functional ingredient for the food industry. In this study, BPS was added at concentrations of 1.5, 3.0, and 4.5 g/kg to a minced pork batter to evaluate its performance as a filler and to pork burger patties to evaluate its performance as a natural antioxidant. The effects of BPS were compared with those of carrageenan and ascorbate, which are a conventional binder and antioxidant, respectively. The performance of BPS was similar to that of carrageenan in terms of the cooking yield and texture of the cooked batter. BPS reduced the brightness of fresh patties and appeared to reduce oxidative discolouration during the frozen storage of raw patties. Moreover, BPS reduced the levels of thiobarbituric acid reactive substances (TBARS) during the refrigerated and frozen storage of cooked patties. A greater decrease in TBARS formation was observed with 4.5 g BPS/kg compared with 0.5 g sodium ascorbate/kg during refrigerated storage. In contrast to ascorbate, BPS promoted the presence of lipid-derived volatile compounds induced by thermal breakdown in the headspace of cooked patties. Nonetheless, this effect was reduced as the amount of BPS in the patties increased. In cooked minced meat products, BPS could increase cooking yields and lipid oxidative stability during storage and might result in a more intense flavour.

15.
Sensors (Basel) ; 21(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064285

RESUMO

We report on recent advances in the use of inexpensive polymer optical fibres (POFs) for sensing applications in avionics. The sensors analysed in this manuscript take advantage of the unique properties of polymers, such as high flexibility, elasticity, and sensitivity, and they range from strain, elongation, and vibration interrogators to level and temperature meters, leading to cost-effective techniques for structural health monitoring in aircraft structures. We also highlight recent power-supply methods using Power-over-POF in order to feed sensors remotely, and we discuss the constraints imposed by connectors on the performance of POF networks in aircrafts.

16.
Animals (Basel) ; 10(12)2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33321858

RESUMO

Intrauterine growth restriction (IUGR) is a key developmental programming factor which might impair both the feed efficiency of lambs and meat quality, since it deeply impacts skeletal muscle and adipose tissue development. To determine the effect of birth weight on the growth performance, ruminal parameters, digestibility, non-carcass components, carcass traits, physicochemical characteristics and fatty acid profile of meat, two experimental groups (six animals in each group) of male Merino lambs with different body weights (BW) at birth (low BW (LW; 3.88 ± 0.281 kg) and high BW (HW; 5.80 ± 0.647 kg)) were used. The lambs were penned with their corresponding ewe during the natural suckling period, being weaned at 15 kg. Then, the lambs were penned individually and offered a complete pelleted diet during the fattening period. All the animals were slaughtered when they reached 27 kg of BW. After weaning, both daily dry matter intake (578 vs. 615 g/day; p = 0.021) and average daily gain (141 vs. 190 g/day; p = 0.004) were significantly lower in LW lambs, and a higher feed:gain ratio was recorded for this group (3.98 vs. 3.45; p = 0.008). Carcass traits did not show differences (p > 0.05) between both groups of lambs, except for higher chilling losses for the LW group (3.29 vs. 2.69%; p = 0.012). Additionally, higher amounts of kidney knob and channel fat were observed for LW lambs (85.4 vs. 152 g; p = 0.028). Apart from a higher hardness of meat in LW lambs (152 vs. 189 Newtons, p = 0.040), no other differences (p > 0.05) were observed in the physicochemical traits of this product; however, the meat of LW lambs tended (p = 0.057) to contain more total fatty acid content with a higher (p = 0.041) proportion of saturated fatty acids than the meat of HW lambs. In conclusion, under the conditions of the present study, a low body weight at birth increased the deposition of fat in carcass and non-carcass components during the fattening period of lambs, thus reducing animal performance and worsening the nutritional indexes of the meat. Accordingly, it seems reasonable to try to identify these animals during early life, to be sold as suckling lambs in the meat market instead of being fattened.

17.
Animals (Basel) ; 10(11)2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33233459

RESUMO

Thirty Assaf male lambs (30 ± 1.9 kg of body weight) were allocated to three groups fed diets differing in their crude protein (CP) contents (low protein (LP), 134 g CP/kg dry matter (DM); medium protein (MP), 157 g CP/kg DM; and high protein (HP), 173 g CP/kg DM) to test the effect of dietary protein content on animal performance, rumen function, animal health, and carcass and meat quality. Feed intake was recorded daily, and animals were weighed every second week. Lambs were blood-sampled to determine their acid-base status and biochemical profile. After 70 days of trial, lambs were slaughtered, and the ruminal content was collected to assess ruminal fermentation. Finally, carcass and meat quality were evaluated. Dry matter intake and average daily gain increased (p < 0.05) when increasing the level of dietary CP. There were not significant differences (p > 0.05) in the evaluated parameters in the rumen fluid of lambs. There were not significant differences in carcass or meat quality (p > 0.05) and in those parameters related to blood acid-base status. Several biochemical parameters showed differences depending on diet CP level (urea, protein, albumin, glucose, and calcium; p < 0.05). Feeding costs calculated in relation to cold carcass weight decreased when dietary CP decreased. The results suggested that a dietary protein content greater than 157 g/kg DM would be required to maximize growth performance in Assaf male fattening lambs under 50 kg of body weight. However, a protein content beyond that level was not found to improve either carcass or meat quality and could worsen profitability.

18.
Heliyon ; 6(10): e05251, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33088979

RESUMO

Changes in the levels of pH, lactic acid, acetic acid, headspace volatile compounds, and spoilage odour intensity during a 35 day refrigerated storage period in two sets of a Balkan-style fresh sausage, a control sausage (CON) and a sausage containing an aqueous hop extract (HOP), packaged under a 20% CO2 and 80% N2 atmosphere were evaluated. Storage resulted in progressive sausage acidification and increased the levels of acetic acid, 1-methylbutanol, ethyl acetate, ethyl hexanoate, and 2-ethylhexanol; all of which are associated with anaerobic microbial metabolism under sugar restricted conditions. Storage decreased the levels of hexanal, heptanal, pentanol, and garlic-derived organosulfur compounds. Hop extract showed oxygen scavenging abilities, and decreased the levels of the volatile compounds derived from lipid auto-oxidation while contributing to the presence of specific terpene compounds. The use of hop extract did not improve the shelf life of sausages packed under anaerobic atmosphere. The spoilage odour appeared in both types of sausages on the 14th day, and it was considered strong from day 21 onwards.

19.
Foods ; 9(3)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178268

RESUMO

Shiga toxin-producing Escherichia coli O157:H7 is a food-borne pathogen and the major cause of hemorrhagic colitis. Pseudomonas is the genus most frequent psychrotrophic spoilage microorganisms present in milk. Two-species bacterial systems with E. coli O157:H7, non-pathogenic E. coli, and P. fluorescens in skimmed milk at 7, 13, 19, or 25 °C were studied. Bacterial interactions were modelled after applying a Bayesian approach. No direct correlation between P. fluorescens's growth rate and its effect on the maximum population densities of E. coli species was found. The results show the complexity of the interactions between two species in a food model. The use of natural microbiota members to control foodborne pathogens could be useful to improve food safety during the processing and storage of refrigerated foods.

20.
Antibiotics (Basel) ; 8(4)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683578

RESUMO

Microbial pathogens are the cause of many foodborne diseases after the ingestion of contaminated food. Several preservation methods have been developed to assure microbial food safety, as well as nutritional values and sensory characteristics of food. However, the demand for natural antimicrobial agents is increasing due to consumers' concern on health issues. Moreover, the use of antibiotics is leading to multidrug resistant microorganisms reinforcing the focus of researchers and the food industry on natural antimicrobials. Natural antimicrobial compounds from plants, animals, bacteria, viruses, algae and mushrooms are covered. Finally, new perspectives from researchers in the field and the interest of the food industry in innovations are reviewed. These new approaches should be useful for controlling foodborne bacterial pathogens; furthermore, the shelf-life of food would be extended.

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