Bio-electrochemical production of hydrogen and electricity from organic waste: preliminary assessment

Clean Technologies and Environmental Policy - This study investigated the performance of a novel integrated bio-electrochemical system for synergistic hydrogen production from a process combining a...     

Modeling of coagulation,curd firming,and syneresis of goat milk from 6 breeds

Traditional milk coagulation properties are used to predict the suitability of milk for cheese-making. In bovine and ovine species, the introduction of the concept of curd firming over time, continuously recorded by a lactodynamograph during prolonged tests, provides additional information about milk coagulation, curd-firming, and syneresis processes. The aims of present study were (1) to test the adaptability of a 4-parameter curd-firming model in the assessment of goat milk (also comparing published data of other species); (2) to describe variability of coagulation, curd firming, and syneresis processes among individual goat milk samples; (3) to quantify the effects of farm and animal factors (breed, parity, and stage of lactation); and (4) to compare 6 goat breeds for their model parameters. Milk samples from 1,272 goats reared in 35 farms were collected. Goats were of 6 breeds: Saanen and Camosciata delle Alpi for the Alpine type; and Murciano-Granadina, Maltese, Sarda, and Sarda Primitiva for the Mediterranean type. During a lactodynamographic analysis (60 min), 240 measures of curd firmness (mm) were recorded for each milk sample. The modeling of curd firming allowed us to achieve the rennet coagulation time estimated on the basis of all the data points (min); the curd firming and the curd syneresis instant rate constants; the asymptotical potential value of curd firming; the actual maximum curd firmness; and the time at which the curd firming maximum level is attained. Modeling parameter data were analyzed using a linear mixed model. Comparison with other dairy species showed several differences: goat milk coagulated later than sheep but earlier than bovine, and curd firming and curd syneresis instant rate constants were greater in small ruminants. Modeling parameters of goat milk were mostly affected by the farm effect (37% of the total variance, on average) compared with the results found for bovine and ovine samples, and this was probably attributable to the marked differences among goat farming systems. Small differences were demonstrated between Alpine and Mediterranean breeds, but the time of maximum curd firmness was lower in Murciano-Granadina compared with Maltese, Sarda, and Sarda Primitiva. Sarda and Sarda Primitiva were very similar and exhibited the most favorable coagulation properties of milk. For almost all the model parameters, the direct effect of breed was increased after correction for milk yield and composition. In conclusion, this approach allowed us to fully depict the effects of the different factors on coagulation of goat milk, and clarified the different renneting pattern among goat breeds, and with other species. Results could be used for the valorization of goat dairy products, also when these are linked to particular local breeds, and to stimulate further studies about relationships between coagulation and cheese-making traits.     

Effect of composition on coagulation,curd firming,and syneresis of goat milk

The present study investigated the effect of different levels of fat, protein, and casein on (1) traditional milk coagulation properties, and (2) curd firming over time parameters of 1,272 goat milk samples. Relationships between fat, protein, and casein and some indicators of udder health status (lactose, pH, somatic cells, bacterial count, and NaCl) were also investigated. Traditional milk coagulation properties and modeled curd-firming parameters were analyzed using a mixed model that considered the effect of days in milk, parity, farm, breed, the pendulum of the instrument, and different levels of fat, protein, and casein. Fat, protein, and casein were also tested with the same model but one at a time. Information provided by this model demonstrated the effect of one component alone, without contemporarily considering that of the others. The results allowed us to clarify the effect of the major milk nutrients on coagulation, curd firming, and syneresis ability of goat milk. In particular, milk rich in fat was associated with better coagulation properties, whereas milk rich in protein was associated with delayed coagulation. The high correlation of fat with protein and casein contents suggests that the effect of fat on the cheese-making process is also attributable to the effects of protein and casein. When only protein or only casein was included in the statistical model, the pattern of coagulation, curd firming, and syneresis was almost indistinguishable. The contemporary inclusion of protein and casein in the statistical model did not generate computing problems and allowed us to better characterize the role of protein and casein. Consequently, given their strong association, we also tested the effect of casein-to-protein ratio (i.e., casein number). Higher values of casein number led to a general improvement in the coagulation ability of milk, suggesting that casein-to-protein ratio, not just protein or casein, should be considered when milk is destined for cheese making. These results are especially useful for dairy farmers who want to increase their profits by improving the technological quality of the milk produced.     

Microbiological safety and quality of Mozzarella cheese assessed by the microbiological survey method

Dairy products are characterized by reduced shelf life because they are an excellent growth medium for a wide range of microorganisms. For this reason, it is important to monitor the microbiological quality of dairy products and, in particular, the total viable count and concentration of Escherichia coli, as they are indicators of the hygienic state of these products. In addition, in dairy products such as Mozzarella cheese, it is important to monitor the concentration of lactic acid bacteria (LAB), as they are the major components of starter cultures used in cheese production, contributing to the taste and texture of fermented products and inhibiting food spoilage bacteria by producing growth-inhibiting substances. For these reasons, to ensure the quality and safety of their products, cheese makers should monitor frequently, during fresh cheese production, the concentration of LAB and spoilage bacteria. However, usually, small- to medium-size dairy factories do not have an internal microbiological laboratory and external laboratories of analysis are often too expensive and require several days for the results. Compared with traditional methods, the microbiological survey (MBS) method developed by Roma Tre University (Rome, Italy) allows faster and less-expensive microbiological analyses to be conducted wherever they are necessary, without the need for a microbiological laboratory or any instrumentation other than MBS vials and a thermostat. In this paper, we report the primary validation of the MBS method to monitor LAB concentration in Mozzarella cheese and the analysis, using the MBS method, of total viable count, E. coli, and LAB concentrations in the production line of Mozzarella cheese as well as during the shelf life of the product stored at 20°C. The results obtained indicate that the MBS method may be successfully used by small- to medium-size dairy factories that do not have an internal microbiological laboratory. Using the MBS method, these dairy factories can monitor autonomously the microbiological safety and quality of their products, saving both time and money.     

Cheese yield,cheesemaking efficiency,and daily production of 6 breeds of goats

Little is known about the complex process of cheesemaking at the individual level of dairy goats because of the difficulties of producing a high number of model cheeses. The objectives of this work were (1) to study the cheesemaking ability of goat milk; (2) to investigate the variability of cheesemaking-related traits among different farms; (3) to assess the effects of stage of lactation and parity; and (4) to compare 6 breeds of goat (Saanen and Camosciata delle Alpi for the Alpine type; Murciano-Granadina, Maltese, Sarda and Sarda Primitiva for the Mediterranean type) for their cheesemaking ability. For each goat (n = 560) we studied (1) 8 milk quality traits (fat, protein, total solids, casein, lactose, pH, somatic cell score, and bacterial count); (2) 4 milk nutrient recovery traits (fat, protein, total solids, and energy) in curd; (3) 3 actual cheese yield traits (fresh cheese, cheese solids, and cheese water); (4) 2 theoretical cheese yield values (fresh cheese and cheese solids) and the related cheesemaking efficiencies; and (5) daily milk yield and 3 daily cheese yield traits (fresh cheese, cheese solids, and water retained in the curd). With respect to individual animal factors, farm was not particularly important for recovery traits or actual and theoretical cheese yield and estimates of efficiency, whereas it highly influenced daily productions. Parity of goats influenced daily cheese production, whereas DIM slightly affected recovery as well as percent and daily cheese yield traits. Breed was the most important source of variation for almost all cheesemaking traits. Compared with those of Alpine type, the 4 Mediterranean breeds had, on average, lower daily milk and cheese productions, greater actual and theoretical cheese yield, and higher recovery of nutrients in the curd. Among Alpine type, Camosciata delle Alpi was characterized by greater nutrients recovery than Saanen. Within the 4 Mediterranean types, the 3 Italians produced much less milk per day, with much more fat and protein and greater recovery traits than the Murciano-Granadina, resulting in greater actual cheese yield. Within the Italian breeds, milk from Sarda and Sarda Primitiva was characterized by lower daily yields, higher protein and fat content, and greater recoveries of nutrients than Maltese goats. These results confirmed the potential of goat milk for cheese production and could be useful to give new possibilities and direction in breeding programs.     

High content of biogenic amines in Pecorino cheeses

Pecorino refers to Italian cheeses made exclusively from raw or pasteurized ewes' milk, characterized by a high content of fat matter and it is mainly produced in the Middle and South of Italy by traditional procedures. The autochthonous microbiota plays an important role in the organoleptic traits of Pecorino cheese and it can influence biogenic amines (BA) content.     

Toward a European Eco-label brand for residential buildings: Holistic or by-components approaches?

The Eco-label scheme is becoming ever more important in the environmental certification of products and services, especially in light of the recent ambitious aim of containing greenhouse emissions and improving the efficiency of utilizing energy sources. A recently introduced hypothesis concerns the European Eco-label scheme relating to buildings, in the awareness that the construction industry is of primary importance to the whole economic and social life of states. This scheme should adopt an integrated approach to environmental problems and include construction, day-to-day management, and the possible disposal of building materials, throughout the life cycle of the building. In addition, in consideration of the particular scope of buildings, the main aim of this new scheme should also be to ensure enhanced conditions of comfort to the occupants of these buildings. In sight of this challenge, the building can be regarded as a summation of components (each of them characterized by a given level of environmental quality) or as a unique physical entity aimed at delivering suitable indoor condition to occupants with an assigned amount of primary energy and with a limited impact on the natural environment. In the paper, both approaches will be investigated, keeping also in mind the initiatives that are currently on the ground in the aim of establishing ecological criteria for the award of the Community Eco-label for buildings.     

Effects of oxytocin and prosocial behavior on brain responses to direct and vicariously experienced pain.

In this study, we tested the validity of 2 popular assumptions about empathy: (a) empathy can be enhanced by oxytocin, a neuropeptide known to be crucial in affiliative behavior, and (b) individual differences in prosocial behavior are positively associated with empathic brain responses. To do so, we measured brain activity in a double-blind placebo-controlled study of 20 male participants either receiving painful stimulation to their own hand (self condition) or observing their female partner receiving painful stimulation to her hand (other condition). Prosocial behavior was measured using a monetary economic interaction game with which participants classified as prosocial (N = 12) or selfish (N = 6), depending on whether they cooperated with another player. Empathy-relevant brain activation (anterior insula) was neither enhanced by oxytocin nor positively associated with prosocial behavior. However, oxytocin reduced amygdala activation when participants received painful stimulation themselves (in the nonsocial condition). Surprisingly, this effect was driven by "selfish" participants. The results suggest that selfish individuals may not be as rational and unemotional as usually suggested, their actions being determined by their feeling anxious rather than by reason. (PsycINFO Database Record (c) 2010 APA, all rights reserved)