Color stability of Bos indicus bull steaks in modified atmosphere packaging (MAP)

Evaluations of meat quality, including color, influence purchasing decisions and can be affected by type of fresh meat the packaging system. In this study, fresh steaks from Bos indicus bull were packaged in the vacuum (vacuum), 75% O2/25% CO2 (HiOx-MAP) and 40% CO2/0.4% CO/59.6% N2 (CO-MAP). Emphasis is placed on the color and lipid oxidation of bull beef steaks. Results reveal that the steaks stored in CO-MAP and HiOx-MAP exhibited similar or brighter red color than fresh steaks (exposed only to oxygen) or vacuum. The red color of the LD bull beef steaks packaged in CO-MAP was more intense than the color of meat stored in HiOx-MAP after the 14th day of storage. Vacuum packing dramatically impaired the color of the LD bull steaks, which were severely discolored (brown) after all storage times. Bos indicus steaks of all treatments showed extremely low TBARS values in all storage times. The results suggested that HiOx-MAP or CO-MAP may be utilized to stabilize or improve the red color of fresh steaks from bull of so appreciated by the consumer.Evaluations of meat quality, including color, influence purchasing decisions and can be affected by type of fresh meat the packaging system. In this study, fresh steaks from Bos indicus bull were packaged in the vacuum (vacuum), 75% O2/25% CO2 (HiOx-MAP) and 40% CO2/0.4% CO/59.6% N2 (CO-MAP). Emphasis is placed on the color and lipid oxidation of bull beef steaks. Results reveal that the steaks stored in CO-MAP and HiOx-MAPexhibited similar or brighter red color than fresh steaks (exposed only to oxygen) or vacuum. The red color of the LD bull beef steaks packaged in CO-MAP was more intense than the color of meat stored in HiOx-MAP after the 14th day of storage. Vacuum packing dramatically impaired the color of the LD bull steaks, which were severely discolored (brown) after all storage times. Bos indicus steaks of all treatments showed extremely low TBARS values in all storage times. The results suggested that HiOx-MAP or CO-MAP may be utilized to stabilize or improve the red color of fresh steaks from bull of so appreciated by the consumer

A forced thermal ratchet in a memory heat bath

The present work studies a non-Markovian forced thermal ratchet model on an asymmetric periodic potential. The Brownian dynamics is described by a generalized Langevin equation with an Ornstein-Uhlenbeck-type friction memory kernel. We show that for the case of a time-dependent driving force, also in the form of an Ornstein-Uhlenbeck-like process, an exact expression of the probability current can be derived. We also obtain the behavior of the particle's average rate of flow as a function of the external amplitude force and of the bath temperature when the driving force behaves as a square wave modulation. All our results are compared with those obtained in the Markovian case and we find, fairly remarkably, that in some cases a friction memory kernel results in an enhancement of the curren

Are sensory attributes and acceptance influenced by nutritional and health claims of low-sodium salami? Preliminary study with Brazilian consumers

The first contact between consumers and the food product is usually the packaging and it’s labelling. Therefore, it is the primary means to generate consumer’s expectations. The aim of the present work was to evaluate the influence of nutritional and health claims on acceptance of salami with reduced sodium content, aimed at finding guidance for the product reformulation. Sixty consumers evaluated four samples of salami. The overall acceptance was evaluated using a nine-point hedonic scale, and the attributes color, tenderness, characteristic flavor and salt content, were evaluated by 7 – point just-about-right (JAR) scale. For the expectation test, overall liking of salami with reduced sodium content was evaluated by consumers under three conditions: (1) blind test (B); (2) expectation generated by nutritional and health claims (E), and (3) consumers re-tasted the salami having the nutrition and health claims available (R). Student’s t-tests performed on data indicated no significant differences (p > 0.05) between the mean acceptance under the blind (B) and real (R) conditions, although expectation ratings (E) were significantly higher than (B) (p ≤ 0.05). However, linear regression of (R - B) x (E - B) ratings revealed a major assimilation effect of expectation, especially under negative disconfirmation (E > B). Contrast effect was also observed, but to a lesser extent. The results showed that saltiness attribute was not decisive in decreased acceptance according to the JAR scale, but it was relevant in the aftertaste generated by adding salt substitutes. Finally, nutritional and health claims had little effect on consumer acceptance

Las Cortes de Cádiz y la Imagen de América. La visión etnográfica y geográfica del nuevo mundo

La monografía que presentamos, elaborada originalmente por encargo editorial de la Fundación Rafael Alberti, aborda una faceta hasta ahora prácticamente inédita en los estudios relacionados con las Cortes de Cádiz y el mundo americano. Hasta el presente han sido tratados en profundidad los temas concernientes a la participación de los representantes ultramarinos en la magna convención gaditana, a la temática indígena y a los problemas de la intervención política de los diputados indianos en las distintas fases de las Cortes Extraordinarias. Pero permanecía, sin embargo, inédito un aspecto sumamente sugestivo de las relaciones de los diputados doceañistas con los territorios de Ultramar: los múltiples intentos para hacer realidad y dar cumplimiento a un viejo axioma cuyos precedentes hay que buscarlos en el reinado de Felipe II: "conocer América para gobernar América". En efecto; el estudio que hoy ponemos a disposición del especialista demuestra hasta qué punto los diputados gaditanos, a través de la Secretaría de Gobernación de Ultramar del Consejo de Regencia, pensaron en América en clave de modernidad. Ello se materializó en la promulgación de numerosas disposiciones encaminadas a escrutar la realidad etnográfica, demográfica, económica, social y geográfica del Nuevo Mundo con objeto de lograr una mayor gobernabilidad de las tierras de Ultramar dentro del principio ilustrado de la felicidad del ciudadano

Effect of electron-withdrawing substituents on the electrophilicity of carbonyl carbons

Indexación: ScopusThe substituent effects on the carbonyl carbon atom for a series of twelve substituted phenyl acetates have been rationalized using a global electrophilicity index. This index is linearly correlated with the experimental reaction rate coefficients. We found that, in contrast to the proposed interpretation based on experimental 13C NMR chemical shifts and ground state destabilization calculations, the electrophilicity of carbonyl compounds increases due to the effect promoted by electron-withdrawing groups in these systems.https://www.sciencedirect.com/science/article/pii/S0040402004018046?via%3Dihu

Inherently Safer Design and Optimization of Intensified Separation Processes for Furfural Production

Currently furfural production has been the subject of increased interest because it is a biobased chemical able to compete with fossil-based chemicals. Furfural is characterized by flammability, explosion, and toxicity properties. Improper handling and process design can lead to catastrophic accidents. Hence it is of most importance to use inherent safety concepts during the design stage. This work is the first to present several new downstream separation processes for furfural purification, which are designed using an optimization approach that simultaneously considers safety criteria in addition to the total annual cost and the eco-indicator 99. The proposed schemes include thermally coupled configuration, thermodynamic equivalent configuration, dividing-wall column, and a heat integrated configuration. These are compared with the traditional separation process of furfural known as the Quaker Oats Process. The results show that because of a large amount of water present in the feed, similar values are obtained for total annual cost and eco-indicator 99 in all cases. Moreover, the topology of the processes has an important role in the safety criteria. The thermodynamic equivalent configuration resulted as the safest alternative with a 40% reduction of the inherent risk with respect to the Quaker Oats Process, and thus it is the safest option to purify furfural

Sensory and physicochemical characteristics of low sodium salami

The aim of the present study was to develop low sodium salami prepared with pork, low-fat beef and a small quantity of pork back fat (150 g kg−1). Sodium chloride (NaCl) was replaced by potassium chloride (KCl) and calcium chloride (CaCl2), and salamis were tasted to obtain low-salt salami with sensory characteristics similar to those found in commercial ones. Salamis were prepared following seven different treatments. Treatments included five different combinations of KCl and CaCl2 which varied from 5 g kg−1 to 10 g kg−1 and two controls containing high (25 g kg−1) and low (10 g kg−1) concentrations of NaCl. The right level of saltiness of each treatment was evaluated on “just-about-right” (JAR) scales and analyzed by Penalty Analysis. The results showed differences in pH and Aw (water activity) due to NaCl reduction. Salt replacement mixtures of KCl/CaCl2 in salamis did not affect this process technologically (slicing, appearance and texture), and the decrease in Na content was approximately 55 %. Although no significant differences were observed in appearance, treatments differed (p ≤ 0.05) in flavor, texture, and overall liking. As regards salt content of salami, consumers considered treatments with low NaCl content and replacers KCl and CaCl2 (% Na) as having an acceptable level of saltiness. However, this replacement produced a strange taste. Thus, the production of low sodium salamis using salt replacers (KCl and CaCl2) or salamis without replacers with a value higher than 1 % of NaCl can be used effectively without compromising major sensorial attributes

Chemical composition and antibacterial and antioxidant activity of a citrus essential oil and its fractions

ABSTRACT Essential oils (EOs) from Citrus are the main by-product of Citrus-processing industries. In addition to food/beverage and cosmetic applications, citrus EOs could also potentially be used as an alternative to antibiotics in food-producing animals. A commercial citrus EO—Brazilian Orange Terpenes (BOT)—was fractionated by vacuum fractional distillation to separate BOT into various fractions: F1, F2, F3, and F4. Next, the chemical composition and biological activities of BOT and its fractions were characterized. Results showed the three first fractions had a high relative amount of limonene (≥10.86), even higher than the whole BOT. Conversely, F4 presented a larger relative amount of BOT’s minor compounds (carvone, cis-carveol, trans-carveol, cis-p-Mentha-2,8-dien-1-ol, and trans-p-Mentha-2,8-dien-1-ol) and a very low relative amount of limonene (0.08–0.13). Antibacterial activity results showed F4 was the only fraction exhibiting this activity, which was selective and higher activity on a pathogenic bacterium (E. coli) than on a beneficial bacterium (Lactobacillus sp.). However, F4 activity was lower than BOT. Similarly, F4 displayed the highest antioxidant activity among fractions (equivalent to BOT). These results indicated that probably those minor compounds that detected in F4 would be more involved in conferring the biological activities for this fraction and consequently for the whole BOT, instead of the major compound, limonene, playing this role exclusively

Chemical composition, antibacterial and antioxidant activities of a citrus essential oil and its fractions

The prohibition of antibiotic use in animal feed since 2006 by the European Community, due to the concern about the growing emergence of bacterial resistance, has led to the search for alternatives to substitute antibiotics. Essential oils (EOs) could be a possible alternative because of their antimicrobial properties. Specifically, citrus EOs, that are by-products of orange juice production, could be an excellent alternative since they have shown a good potential to fight pathogenic bacteria and their use in animal feed could become feasible since there is a high availability of them in the worldwide market. The aims of this study were to evaluate the chemical composition, antibacterial and antioxidant activities of a commercial citrus EO, Brazilian orange terpenes (BOT), and its fractions. Initially, the antibacterial activity of BOT was tested on Escherichia coli U21 (K88 LT/STb/F18/STa) isolated from pig gut and on Lactobacillus rhamnosus ATCC 7469 by a microdilution method. MIC and MBC results showed that E. coli (MIC=MBC=1.85 mg/mL) was more sensitive than L. rhamnosus (MIC=3.7 and MBC=7.4 mg/mL) to BOT, thus it displayed a selective antibacterial activity, affecting more the pathogenic than the beneficial bacteria. Limonene (78.7%) was determined as the major compound in BOT by GC-MS. After that, BOT was subjected to fractional distillation in a pilot system of continuous distillation. Four fractions were obtained: F1, F2, F3, and F4. The first three fractions were characterized by a high relative amount of limonene (86.9; 91.8; 91.9%,) followed by cis-limonene oxide, trans-limonene-oxide, and myrcene. Conversely, F4 was characterized by having the lowest amount of limonene (0.96%) and as having trans-carveol, carvone, cis-p-mentha-2,8-dien-1-ol, and trans-p-mentha-2,8-dien-1-ol as the major compounds. Only F4 was demonstrated to have an activity on E. coli (MIC=MBC=3.7 mg/mL) and L. rhamnosus (MIC=MBC=14.8 mg/mL). The F4 fraction also possessed the highest antioxidant activity (845.7 µmoltrolox/g - ORAC) in contrast to the others fractions (479.7; 334.4; 209.1 µmoltrolox/g, respectively), and even to the EO itself (785.1 µmoltrolox/g). The results imply that the minor compounds were responsible for the biological activity of this EO instead of its major compound limonene