No abstract

Processed meat products frequently suffer from fungal and mycotoxin contamination, mostly ochratoxin A (OTA). Penicillium nordicum is considered responsible for this contamination, but Aspergillus westerdijkiae has recently been associated with high levels of OTA in meat products. Several biocontrol agents have been tested against P. nordicum growth and OTA production in meat products, but A. westerdijkiae has not been considered. The aim of this work was to evaluate in vitro the effect of a commercial starter culture used in sausage fermentation and of sausage-native yeasts on OTA production by A. westerdijkiae, as compared with the highly studied P. nordicum, in meat-based culture media. Four representative yeasts isolated from dry-cured sausage and a commercial starter culture were coinoculated with both fungi in different meat-based media, under varying conditions. Fungal growth was determined by measuring colony diameter, and OTA production was quantified by HPLC-FLD. A. westerdijkiae was significantly stimulated to produce OTA under all tested conditions, and, in ham, OTA production by P. nordicum was stimulated by co-culture with the starter culture. In conclusion, endogenous or added microorganisms enrolled in fermentation or in biocontrol in meat products seem to exert varying responses on different ochratoxigenic fungi, thus leading to unforeseen safety problems.

Bee pollen contains almost all nutrients required by the human organism as well as diverse health-promoting substances. However, its composition and nutritional value greatly depend on the botanical origin. As such, it is important to develop a rapid and non-expensive methodology that allows studying its characteristics, making labelling more objective and easier. The FTIR-ATR technique was used to predict some nutritional parameters in 126 bee pollen samples. FTIR-ATR spectrum obtained in the region between 4000 and 400 cm −1 with PLS Regression models were used to correlate spectral information with the data obtained using reference methods. In this first approach with pollen samples, good correlation models with appropriate accuracy were obtained for the evaluated parameters with r 2 varying from 74.8 to 97% and residual prediction deviation between 2.0 and 5.8. These results suggest that FTIR-ATR may be a useful technique for assessing bee pollen's composition.Aplicació n de la espectroscopía FTIR-ATR a la caracterizació n del polen de abeja El polen de abeja contiene casi todos los nutrientes requeridos por el organismo humano, así como diversas sustancias promotoras de la salud. Sin embargo, su composició n y valor nutricional dependen en gran medida del origen botánico. Como tal, es importante desarrollar una metodología rápida y econó mica que permita estudiar sus características, haciendo el etiquetado más objetivo y más fácil. La técnica FTIR-ATR se utilizó para predecir algunos parámetros nutricionales en 126 muestras de polen de abeja. Se utilizó el espectro FTIR-ATR obtenido en la regió n entre 4000 y 400 cm-1 con modelos de regresió n PLS para correlacionar informació n espectral con los datos obtenidos usando métodos de referencia. En este primer abordaje con muestras de polen, se obtuvieron buenos modelos de correlació n con una precisió n adecuada para los parámetros evaluados con r2 variando de 74,8% a 97% y una desviació n de predicció n residual entre 2,0 y 5,8. Estos resultados sugieren que el FTIR-ATR puede ser una técnica útil para evaluar la composició n del polen de abeja.

No abstract

a b s t r a c tPropolis is a resinous substance collected from plants by bees. Its composition depends on the vegetation, the season, and the source area. It usually contains many chemical compounds such as polyphenols, steroids and amino acids.The hereditary spherocytosis (HS) is a type of anaemia characterized by microcytic and hyperchromic red cells, spherical in shape and without central pallor. Clinically, subjects present from asymptomatic conditions to severe haemolytic anaemia.In this study it was evaluated the effect of two propolis extracts in the osmotic fragility of HS patient red blood cell (RBC) membrane. It was found that propolis decreases the erythrocytes membrane fragility, being the effect of Bornes propolis more pronounced than Fundão propolis'. This effect was related with the higher phenolic content of the former propolis. The results obtained in vitro suggest that the membrane fragility increases under oxidative stress conditions for the patient RBC's and the protection effect of propolis is due to its antioxidant properties. These results open doors for future investigations in order to elucidate the mechanisms, identify the main compounds involved in this fragility protection of the erythrocyte membrane. This is the first work reporting an evaluation of the propolis effect in a blood disease.

PropolisPropolis (bee glue) is a beehive product prepared by bees of the Apis mellifera species, using resinous substances collected from various plants. 15,16 These substances are mixed with the β-glycosidase enzyme of their saliva, partially digested, and added to bee wax to form the final product.This product, commonly referred as a "natural antibiotic", has an important role in protecting, reinforcing and repairing the hives. In addition, any invaders are wrapped in propolis and die by asphyxia, then the bodies are preserved, which prevents the putrefaction of the honeycomb. 17À19 It is also a barrier to molds and yeasts, bacteria, viruses, and rain. Propolis is mainly composed of resins (50%), waxes (30%), essential oils (10%), pollen (5%), and other organic compounds (5%), among which are phenolic compounds, esters, flavonoids, terpenes, aromatic aldeydes and alcohols. 20À23 However, it is worth mentioning that this composition differs significantly with botanical and geographical origin and depends on climatic conditions, terrain, water availability and other environmental factors. 18,24À28 It has been reported that this product has several pharmacological properties, such as antibiotic, anti-neoplastic, anti-inflammatory, 26 anti-diarrheatic, antimicrobial, 29,30 antiviral, 31 antioxidant, 32 hepatoprotective, cardiostatic, 33 antitumoral, 23,34 anti-ulcerus and immunostimulatory activity. 35,36 Other studies highlight its efficiency as an anti-HIV-1, 37 anti-neurodegenerative 38 and anti-tuberculosis agent. 39 Due to these medicinal properties, propolis is generating increasing interest from the pharmaceutical, food and cosmetic industries, and it is currently being introduced in products for human consumption, such as drinks and food additives. 32,40 PHENOLIC AND FLAVONOID COMPOUNDS HoneyPhenolic compounds are one of the most important groups of plant secondary metabolites, comprising at least 8000 different known structures. Their chemical structures range from simple phenolic molecules to high molecular weight polymers of approximately 30000 Da. 41 These compounds are reported to exhibit anticarcinogenic, anti-inflammatory, anti-atherogenic, anti-thrombotic, immune modulating, analgesic, antineoplatic behavior, antiviral activity, antiulcer properties, hormone, antibiotic and cardiovascular activities, among others, and exert these functions as antioxidant activities. 42,43 In addition, flavonoids inhibit lipid peroxidation, platelet aggregation, capillary permeability and the activity of enzyme systems including cyclo-oxygenase and lipoxygenase. 10,44 The honey phenolics and the flavonoids present in honey are divided into three classes with similar structure; flavonols, flavones and flavanones. These are important due to their contribution to honey color, taste and flavor and also due to their beneficial effects on health. In honey, propolis and royal jelly, most of the phenolic compounds are present in the form of flavonoids, whose concentration depends on various factors, including the plant spe...

Linguiça is a Portuguese traditional fermented sausage whose microbiological quality and safety can be highly variable. In order to elucidate risk factors and the particularities of the manufacturing technology that explain the between-batch variability in total viable counts (TVC), Enterobacteriaceae, Staphylococcus aureus and Listeria monocytogenes in the product; microbiological and physicochemical characterisation of linguiça at five stages of production (i.e., raw pork meat, mixed with ingredients, macerated, smoked and ripened) was carried out. A total of six production batches were surveyed from two factories; one utilised curing salts and polyphosphate in their formulation (Factory II). The delayed fermentation in the nitrite-formulated sausages was partly responsible for the increase (p<0.01) in Enterobacteriaceae, S. aureus and L. monocytogenes from raw meat (3.21logCFU/g, 1.30logCFU/g and 22.2CFU/g, respectively) to the end of maceration (4.14logCFU/g, 2.10logCFU/g and 140CFU/g, respectively) while the better acidification process in the nitrite-free sausages (Factory I) led to lower counts of S. aureus (2.64logCFU/g) and L. monocytogenes (10CFU/g) in the finished products. In Factory II, although L. monocytogenes entered the chain at the point of mixing, it became steadily inactivated during smoking and ripening (<50CFU/g), despite the initially-delayed fermentation. Nitrite had a strong effect on reducing Enterobacteriaceae throughout smoking (r=-0.73) and ripening (r=-0.59), while it failed to control the growth of S. aureus. The main hurdle preventing the development of S. aureus in linguiça is the pH, and other factors contributing to its control are: longer ripening days (p=0.019), low S. aureus in raw meat (p=0.098), properly-washed casings (p=0.094), and less contamination during mixing (p=0.199). In the case of L. monocytogenes, at least three hurdles hinder its development in linguiça: low a (p=0.004), low pH (p=0.040) and nitrite (p=0.060), and other factors contributing to its control are: longer ripening (p=0.072) and maceration (p=0.106) periods, lower a at the end of smoking (p=0.076) and properly-washed casings (p=0.099). Results have shown that there is a need to standardise the productive process of linguiça, to optimise the initial acidification process, and to reinforce proper programmes of quality control of ingredients and good hygiene practices, so as to minimise the introduction of Enterobacteriaceae and pathogens from external sources.

Mead is a traditional alcoholic beverage obtained by fermenting mead wort; however, its production still remains frequently an empirical exercise. Different meads can be produced, depending on fermentation conditions. Nevertheless, to date few studies have been developed on factors that may infl uence mead quality. The main objective of this work was to study the infl uence of sweetness and ethanol content on mead acceptability. Different meads were produced with two sweetness levels (sweet and dry meads) and three ethanol contents (18, 20, 22% (v/v)), adjusted by brandy addition. Afterwards, meads acceptability was evaluated by sensory analysis through a consumers' panel (n=108) along with chemical analysis by HPLC-RID of glucose, fructose, ethanol, glycerol and acetic acid.The sweet (75 g glucose+fructose /L) and dry (23 g glucose+fructose /L) meads presented glycerol contents equal to 5.10±0.54 and 5.96±0.95 g/L, respectively, that were desirable since glycerol improves mead quality. Low concentrations of acetic acid were determined (0.46±0.08 and 0.57±0.09 g/L), avoiding the vinegar off-character. Concerning sensory analysis, the alcohol content of mead had no effect on the sensory attributes studied, namely, aroma, sweetness, fl avour, alcohol feeling and general appreciation. Regarding sweetness, the "sweet meads" were the most appreciated by the consumers (score of 5.4±2.56), whereas the "dry meads" (score of 2.7±2.23) showed low acceptability. In conclusion, this work revealed that sweetness is a sensory key attribute for mead acceptance by the consumers, whereas ethanol content (18 to 22% (v/v)) is not.