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1.
Foods ; 9(6)2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32517162

RESUMO

Durum wheat is widespread in the Mediterranean area, mainly in southern Italy, where traditional durum wheat breadmaking is consolidated. Bread is often prepared by adding a lot of salt to the dough. However, evidence suggests that excessive salt in a diet is a disease risk factor. The aim of this work is to study the effect of a natural low-sodium sea salt (Saltwell®) on bread-quality parameters and shelf-life. Bread samples were prepared using different levels of traditional sea salt and Saltwell®. The loaves were packaged in modified atmosphere conditions (MAPs) and monitored over 90 days of storage. No significant differences (p ≤ 0.05) were found in specific volumes and bread yield between the breads and over storage times, regardless of the type and quantity of salt used. Textural data, however, showed some significant differences (p ≤ 0.01) between the breads and storage times. 5-hydroxymethylfurfural (HMF) is considered, nowadays, as an emerging ubiquitous processing contaminant; bread with the lowest level of Saltwell® had the lowest HMF content, and during storage, a decrease content was highlighted. Sensory data showed that the loaves had a similar rating (p ≤ 0.05) and differed only in salt content before storage. This study has found that durum wheat bread can make a nutritional claim of being "low in sodium" and "very low in sodium".

2.
Front Nutr ; 6: 13, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30815437

RESUMO

The aim of this work was to evaluate the effect of the addition of citrus fibers, from blood orange and lemon peels to produce a functional durum wheat bread. Breads fortified in fiber were packaged under a modified atmosphere (MAP) and stored at 25°C up to 120 days. No significant differences were observed with respect to the specific volume and weight, internal structure, pH and titratable acidity among the bread samples obtained using different types and percentages of fibers. Storage time, at 30 up to 90 days, affected significantly the bread firmness and caused significant differences in 5-hydroxymethylfurfural (HMF) levels in all bread samples. In fortified breads with citrus fibers the yeast and mold counts showed values of approximately 1 log10 cfu/g for the first 30 days and 3.5 log10 cfu/g at the end of storage. The results of the sensory evaluation highlight that loaves enriched with blood orange and lemon fibers showed a citrus flavor but had a similar overall evaluation respect to control bread produced without addition of citrus fiber. The results of this study showed that the addition up to 2% of blood orange and lemon fibers in wheat whole durum flour is a possible strategy to produce "high fibre" bread.

3.
J Food Sci Technol ; 55(11): 4458-4467, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30333642

RESUMO

The aim of this study was to develop fortified breads of durum wheat semolina (DW) partially substituted at 10%, 15%, 20% and 30% with white sorghum or yellow pea wholemeal flours (WS, YP, respectively) or using wholemeal flour from a natural mixture of rye and durum wheat (RDW). The physico-chemical composition of the raw materials, rheological properties of dough, the bread quality characteristics, glycaemic index and sensory quality of bread were examined. Compared to 100% DW, 100% YP had twice the protein levels, RDW had almost three times the dietary fibre, while the colorimetric indices for WS and YP flour addition showed increased redness (for RDW) and similar yellowness (for YP). With respect to the control dough (100% DW), RDW and addition of WS or YP produced showed negative impact on water absorption (RDW, WS), stability (RDW, YP), dough strength (RDW, WS, YP), tenacity and extensibility ratio (RDW, YP), loaf volume (RDW, WS, YP), yellowness (RDW, WS) and sensory acceptance of bread (RDW, WS). However, these changes were counterbalanced by higher dietary fibre and lower glycaemic index of the breads, especially for RDW and at high additions of WS and YP (20-30%). Moreover, breads fortified with YP were better in terms of colour and overall acceptability scores.

4.
J Food Sci ; 81(9): C2158-66, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27442951

RESUMO

The use of selected plant water extracts to control pests and weeds is gaining growing attention in organic and sustainable agriculture, but the effects that such extracts may exert on the quality aspects of durum wheat are still unexplored. In 2014, 5 plant water extracts (Artemisia arborescens, Euphorbia characias, Rhus coriaria, Thymus vulgaris, Lantana camara) were prepared and distributed on durum wheat cv Valbelice to evaluate their potential herbicidal effects. After crop harvesting, the major physicochemical and technological parameters of wholemeal flours obtained from each treatment were measured and compared with those from chemical weeding and untreated controls. A baking test was also performed to evaluate the breadmaking quality. In wholemeal flours obtained after the treatment with plant extracts protein and dry gluten content were higher than in control and chemical weeding. Wholemeal flours obtained after chemical weeding reached the highest Mixograph parameters, and that from durum wheat treated with R. coriaria extract demonstrated a very high α-amylase activity. We concluded that the treatments with plant water extracts may influence many quality traits of durum wheat. This occurrence must be taken into account in overall decisions concerning the use of plant extracts in pest and weed management practice.


Assuntos
Pão/análise , Farinha/análise , Manipulação de Alimentos , Triticum/química , Grãos Integrais/química , Qualidade dos Alimentos , Glutens/química , Extratos Vegetais/análise , Proteínas de Plantas/química , Água/química , alfa-Amilases/metabolismo
5.
Food Chem ; 186: 271-6, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25976821

RESUMO

In this paper, four different olive cultivars from Southern Italy, Carolea, Cassanese, Nocellara del Belice, Nocellara Messinese table olives, produced according to traditional fermentation processes, were evaluated with the aim of assessing the effect of selected starter cultures on growth of bacterial population and on olive phenols during fermentation. Only Cassanese and Nocellara del Belice inoculated samples reached a safe pH value under 4.6 after 90 days while maintaining it until the end of storage. The most representative phenols in brine samples analysed by HPLC-MS/MS were hydroxytyrosol and verbascoside. Among the analysed phenols, only hydroxytyrosol, caffeic acid and ferulic acid always increased during fermentation, while the others increased up to 90-120 days and then decreased. The Principal Component Analysis (PCA) performed on pH and phenol values highlighted three clusters of olive cultivars. Throughout the brining period, lactic acid bacteria were always present while staphylococci and coliform bacteria disappeared after 30 and 90 days, respectively.


Assuntos
Fermentação , Frutas/química , Frutas/microbiologia , Lactobacillus plantarum/metabolismo , Olea , Fenóis/análise , Microbiologia de Alimentos , Itália , Sais
6.
Microorganisms ; 3(4): 588-611, 2015 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27682107

RESUMO

The yeasts constitute a large group of microorganisms characterized by the ability to grow and survive in different and stressful conditions and then to colonize a wide range of environmental and human ecosystems. The competitive traits against other microorganisms have attracted increasing attention from scientists, who proposed their successful application as bioprotective agents in the agricultural, food and medical sectors. These antagonistic activities rely on the competition for nutrients, production and tolerance of high concentrations of ethanol, as well as the synthesis of a large class of antimicrobial compounds, known as killer toxins, which showed clearly a large spectrum of activity against food spoilage microorganisms, but also against plant, animal and human pathogens. This review describes the antimicrobial mechanisms involved in the antagonistic activity, their applications in the processed and unprocessed food sectors, as well as the future perspectives in the development of new bio-drugs, which may overcome the limitations connected to conventional antimicrobial and drug resistance.

7.
Yeast ; 30(1): 33-43, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23148020

RESUMO

Wickerhamomyces anomalus killer strains are important for fighting pathogenic yeasts and for controlling harmful yeasts and bacteria in the food industry. Targeted disruption of key genes in ß-glucan synthesis of a sensitive Saccharomyces cerevisiae strain conferred resistance to the toxins of W. anomalus strains BS91, BCA15 and BCU24 isolated from olive brine. Competitive inhibition of the killing activities by laminarin and pustulan refer to ß-1,3- and ß-1,6-glucans as the main primary toxin targets. The extracellular exoglucanase-encoding genes WaEXG1 and WaEXG2 from the three strains were sequenced and were found to display noticeable similarities to those from known potent W. anomalus killer strains.


Assuntos
Glicosídeo Hidrolases/genética , Olea/microbiologia , Saccharomycetales/enzimologia , Saccharomycetales/genética , Sais , DNA Fúngico/química , DNA Fúngico/genética , Glicosídeo Hidrolases/metabolismo , Dados de Sequência Molecular , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA
8.
Food Microbiol ; 30(1): 219-25, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22265304

RESUMO

Killer Saccharomyces cerevisiae and Wickerhamomyces anomalus yeast strains were tested as biocontrol agents against Penicillium digitatum, one the most important causes of postharvest decay in orange fruits. W. anomalus, grown on acidified medium, demonstrated micocinogenic activity against P. digitatum, as indicated by large inhibition halos and hyphal damage resulting from ß-glucanase activity. Oranges that had been deliberately inoculated with pathogens were protected from decay by W. anomalus. Inoculation of oranges with W. anomalus strains BS 91 and BS 92 reduced disease severity to 1 and 4%, respectively, for up to 10 days in storage.


Assuntos
Agentes de Controle Biológico , Citrus sinensis/microbiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Penicillium/crescimento & desenvolvimento , Leveduras/metabolismo , DNA Fúngico/isolamento & purificação , Endo-1,3(4)-beta-Glucanase/metabolismo , Frutas/microbiologia , Concentração de Íons de Hidrogênio , Penicillium/isolamento & purificação , Doenças das Plantas/microbiologia
9.
Int J Food Microbiol ; 148(1): 15-22, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21570143

RESUMO

The yeast microbiota associated with naturally fermented and inoculated green table olives, differently treated in the field with non-conventional repellent and antiovipositional products in the control of Bactrocera oleae, was analysed using a combination of culture-dependent and -independent molecular fingerprinting. The routine yeast isolation gave rise to 118 strains, whose identification was performed by PCR-RFLP of the internal transcribed spacer (ITS) regions. Total DNA was extracted directly from the brine throughout fermentation by means of an experimental protocol that included the removal of Taq polymerase inhibitors. Denaturing Gradient Gel Electrophoresis (DGGE) of 26S rRNA gene PCR amplicons highlighted the yeast community. Comparison of both culture-dependent and independent methods indicated that the yeast species Saccharomyces cerevisiae, Wickerhamomyces anomalus, Candida diddensiae and Issatchenkia orientalis were dominant during fermentation despite the addition of the Lactobacillus plantarum starter used in brining. The resultant isolated species were unaffected by treatments in field, except for C. diddensiae whose growth was delayed by kaolin.


Assuntos
Fermentação , Controle de Insetos , Olea/microbiologia , Leveduras/isolamento & purificação , Eletroforese em Gel de Gradiente Desnaturante/métodos , Caulim , Lactobacillus plantarum , Reação em Cadeia da Polimerase/métodos , Sais , Leveduras/genética , Leveduras/crescimento & desenvolvimento
10.
FEMS Yeast Res ; 11(6): 487-93, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21575132

RESUMO

An efficient ß-glucosidase (ßG)-producing strain, Wickerhamomyces anomalus BS81, was isolated from naturally fermented olive brine and identified based on PCR/restriction fragment length polymorphism of the rDNA internal transcribed spacer and sequence analysis of the D1/D2 region of the 26S rRNA gene. The hydrolytic activity of the ßG had an optimum pH of 8.5 and an optimum temperature of 35 °C. The enzyme had high substrate specificity and high catalytic efficiency (K(m) 0.99 mM, V(max) 14 U g(-1) of cells) for p-nitrophenyl-ß-d-glucopyranoside. The enzyme was activated by increasing concentrations of NaCl, with maximum activity at 150 g L(-1) NaCl. Although ßGs have been purified and characterized from several other sources, the W. anomalusßG is unique among ßGs because its relative maximum activity occurs at alkaline pH and 35 °C. Moreover, the yeast strain has esterase activity that acts synergistically with ßG to degrade oleuropein to debitter table olives and olive oil.


Assuntos
Saccharomycetales/classificação , Saccharomycetales/enzimologia , beta-Glucosidase/isolamento & purificação , beta-Glucosidase/metabolismo , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Ativadores de Enzimas/metabolismo , Estabilidade Enzimática , Glucosídeos/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Olea/microbiologia , RNA Ribossômico/genética , Saccharomycetales/genética , Saccharomycetales/isolamento & purificação , Análise de Sequência de DNA , Cloreto de Sódio/metabolismo , Especificidade por Substrato , Temperatura , beta-Glucosidase/química
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