Drying dynamics of meat highlighting areas of relevance to dry-aging of beef.

Drying of foods is a processing step, which has a variety of outcomes from improving shelf life and product stability, to reducing weight, or to achieving a targeted product eating quality. Drying is key step in the manufacturing of some dried meat products, such as jerky. It is also a major event that occurs when beef is dry-aged, where beef is exposed to air under defined conditions for an extended aging period. Although the conditions typically used to produce dried meat products are significantly different from those that prevail during dry-aging, both involve a gradual removal of water from muscle. As there is a paucity of research on the kinetics of the dehydration process occurring during dry-aging of beef, this paper comprehensively reviews models used to describe drying kinetics in other beef products, in order to gain insights regarding the key factors that impact water removal from meat. Consideration is given as to how the specific conditions during dry-aging such as air flows used (approximately 2 m/s), high air relative humidity, low temperature, and meat geometry will influence the kinetics of the drying. With regard to modeling, equations derived from Fick's second law of diffusion (e.g., thin-layer models) have been used to describe the drying kinetics of small-sized meat products. However, to apply Fick's law to dry-aging, some different considerations may need to be evaluated such as: tridimensional geometry (i.e., whole muscle); uniform initial moisture content; isotropic diffusion; negligible shrinkage;and a combination of internal and external resistances.

Optimization of protein recovery from bovine lung by pH shift process using response surface methodology.

BACKGROUND: Response surface methodology (RSM) was used in a sequential manner to optimize solubilization and precipitation conditions in the recovery of protein from bovine lung using pH shift. RESULTS: Separate D-optimal designs were employed for protein solubilization and precipitation. Independent variables investigated for protein solubilization were time (10-120 min), temperature (4-20 °C), pH (8.0-11.0) and solvent/sample ratio (2.5-10). Variables for protein precipitation were time (0-60 min) and pH (4.25-6.00). Soluble protein yields ranged from 323 to 649 g kg-1 and the quadratic model for protein solubilization revealed a coefficient of determination R2 of 0.9958. Optimal conditions for maximum protein solubility were extraction time 140 min, temperature 19 °C, pH 10.8 and solvent/sample ratio 13.02. Protein precipitation yields varied from 407 to 667 g kg-1 , giving a coefficient of determination R2 of 0.9335. Optimal conditions for maximum protein precipitation were pH 5.03 and 60 min. Based on the RSM model, solubilization conditions were manipulated to maximize protein solubilization under reduced water and alkaline usage. These conditions were also validated. CONCLUSION: Models for solubilization and precipitation using bovine and porcine lung were validated; predicted and actual yields were in good agreement, showing cross-species applicability of the results. © 2017 Society of Chemical Industry.

Harnessing the Potential of Blood Proteins as Functional Ingredients: A Review of the State of the Art in Blood Processing.

Blood is generated in very large volumes as a by-product in slaughterhouses all around the world. On the one hand, blood generation presents a serious environmental issue because of its high pollutant capacity; however, on the other hand, blood has the potential to be collected and processed to generate high-added-value food ingredients based on its exceptional nutritive value and its excellent functional properties. In this paper, we review the current state of the art for blood processing, from collection to final recovery of protein isolates, the functional properties of blood, impact of processing on functional properties, and potential applications as food ingredients. Furthermore, future challenges are outlined for this underutilized and abundant product from the meat industry.

The impact of ultrasound treatment on glycolytic enzymes when applied to crude extracts from early post-mortem bovine muscle.

The rate of pH decline post - mortem and its interaction with temperature influences the final tenderness of meat, and therefore, the manipulation of the rate of pH decline is a strategy of interest in order to obtain consistent high quality meat. Ultrasound is a potential early post - mortem carcass intervention, which may alter the rate of glycolysis based on its ability to alter enzyme activity. In this study, homogenates (prepared from early post-mortem Longissimus thoracis et lumborum muscle) were subjected to different ultrasound intensities (0 %/60 %/100 % amp) and treatment durations (15/ 30 min). The effect of these treatments on the inherent activity of the glycolytic enzymes was investigated using an in vitro glycolytic buffer model system. It was found that ultrasound treatment intensity and duration had a significant interactive effect on the rate of pH decline, and on reducing sugars and lactic acid concentrations, specifically following the 100 % amp ultrasound for 30 min treatment and between 30 and 240 min incubation. No significant differences in pH or metabolites content were observed between treatments after 1440 min of incubation. No effect of ultrasound intensity or treatment duration was observed on the degradation of glycogen. Under the reported conditions of this trial, it can be concluded that the application of ultrasound has limited potential to have an impact on the glycolytic pathways in bovine muscle.

Assessing the impact of ultrasound on the rate and extent of early post-mortem glycolysis in bovine Longissimus thoracis et lumborum.

The rate of pH decline, early post-mortem, has been identified as a key factor that impacts the tenderness of meat, and manipulating this rate of pH decline is highly relevant to ensure consistent high quality meat. Ultrasound is a potential intervention in early post - mortem muscle that may have an impact on the rate of glycolysis through its ability to alter enzyme activity. Following a variety of different ultrasound treatments frequencies (25 and 45 kHz) and durations (15, 30 and 45 min), it was found, when analysed in muscle, that ultrasound treatment duration, specifically the 30 min treatment, and interaction between treatment duration and frequency, had a significant impact on the rate of pH decline, post - treatment. Frequency did not have a significant effect on the rate of pH decline, post - treatment, in muscle. Ultrasound did not have a significant permanent effect on the activity of glycolytic enzymes present in bovine Longissimus lumborum et thoracis muscle, where no significant differences were observed on the rate of pH decline and rate of change of reducing sugars, glycogen and lactic acid, when analysed in an in vitro glycolytic buffer. It seems that the impact observed in intact muscle is not as a consequence of a permanent change in enzymatic activity, instead indicating an impact on conditions in the muscle which enhanced enzyme activity.

Influence of meat sample geometry on dehydration dynamics during dry-aging of beef.

Meat geometry may impact on the dehydration kinetics during dry-aging influencing the drying rate and, potentially, aspects of meat quality. In this study, three meat geometries (slices, steaks and sections) were prepared from three bovine Longissimuss thoracis et lumborum at 3 days post-mortem and were dry-aged at 2 °C, 75% relative humidity with an airflow of 0.5-2.0 m/s for 22 days (slices), 48 days (sections) and 49 days (steaks). Weights were recorded during dry-aging and drying curves were obtained for the three geometries, with the larger sections showing limited dehydration due to internal resistance to moisture migration from the core to the surface. Seven thin-layer equations were fitted to the dehydration data in order to model the drying kinetics during dry-aging. Thin-layer models described reliably the drying kinetics of the three geometries. In general, reduced k values (h-1) reflected the lower drying rates as thickness increased. The Midilli model provided the best fit for all geometries. Proximate analyses of the three geometries and bloomed colour of sections were measured at the start and the end of the dry-aging period. Moisture loss during dry-aging led to the concentration of protein, fat and ash contents; while no significant differences were found for L*, a* and b* values of sections before and after the dry-aging process. In addition, moisture content, water activity (aw) and LF-NMR measurements were taken at different locations within beef sections to further explore water dynamics during dry-aging.

Impact of sampling location and aging on the Longissimus thoracis et lumborum muscle proteome of dry-aged beef.

This study aimed to explore the differences in the proteome and molecular pathways between two sampling locations (external, internal) of bovine Longissimus thoracis et lumborum (LTL) muscles at 0, 21, and 28 days of dry-aging (i.e. 3, 24, and 31 days post-mortem). It further assessed the impact of post-mortem aging on the meat proteome changes and the biological processes at interplay. Proteins related to defence response to bacterium and regulation of viral entry into host cell were identified to be more abundant on the external location before dry-aging, which may be associated to the oxidative conditions and microbial activity to which post-mortem muscle is exposed during dressing, chilling, and/or quartering of the carcasses. This highlights the relevance of sampling from interior tissues when searching for meat quality biomarkers. As dry-aging progressed, the meat proteome and related biological processes changed differently between sampling locations; proteins related to cell-cell adhesion and ATP metabolic processes pathways were revealed in the external location at 21 and 28 days, respectively. On the other hand, the impact of aging on the proteome of the interior meat samples, evidenced that muscle contraction and structure together with energy metabolism were the major pathways driving dry-aging. Additionally, aging impacted other pathways in the interior tissues, such as regulation of calcium import, neutrophil activation, and regeneration. Overall, the differences in the proteome allowed discriminating the three dry-aging times, regardless of the sampling location. Several proteins were proposed for validation as robust biomarkers to monitor the aging process (tenderization) of dry-aged beef: TTN, GRM4, EEF1A1, LDB3, CILP2, TNNT3, GAPDH, SERPINI1, and OMD.

Dry-aging of beef as a tool to improve meat quality. Impact of processing conditions on the technical and organoleptic meat properties.

Meat consumers are demanding products of higher and consistent quality, with a distinctive flavor and aroma, able to provide a particular sensorial experience when consuming beef. The impact of all the factors affecting the final eating quality, known as the farm to fork approach, has been extensively studied in the last decades. This includes genetic factors, production system, transport, carcass intervention, aging, packaging and cooking method, among others. Aging is, one of the most important steps in producing high quality tender beef. During this step, flavor is developed and the meat is tenderized. Dry-aging although considered a traditional method, is currently attracting attention from consumers, producers and researchers because of the characteristics of the final products in terms of flavor, aroma and texture. This chapter will describe the series of biochemical changes, which combined with the loss of water, generates a final product that is highly appreciated by niche consumers. This will include the changes that the muscle undergoes to be transformed to meat, the main factors driving the dry-aging process and how the flavor and aroma compounds are generated during this process.

Opportunities and perspectives for utilisation of co-products in the meat industry.

Meat co-products are the non-meat components arising from meat processing/fabrication and are generated in large quantities on a daily basis. Co-products are considered as low added-value products, and in general it is difficult for industries to divert efforts into increasing their value. While many of these products can be edible those not used for human consumption or pet food is usually processed to be used as animal feed, fertilizer or fuel. However, to a large extent meat co-products are an excellent source of high nutritive value protein, minerals and vitamins and hence may be better diverted to contribute to alleviate the increasing global demand for protein. In this review the current uses, legislation and potential techniques for meat co-products processing are reviewed with the aim of showing a route to improve meat industry sustainability, profitability and better usage of available resources.

Exploring fasting practices for critical care patients - A web-based survey of UK intensive care units.

BACKGROUND: Enteral nutrition delivery in the critically ill is frequently interrupted for surgical and airway procedures to avoid aspiration of stomach contents. Recurrent fasting leads to under delivery of enteral nutrition and this underfeeding is associated with worse outcomes. International fasting recommendations do not provide guidance for intubated patients receiving enteral nutrition. This study aimed to gain a detailed perspective of UK critical care fasting practices. METHODS: A web-based survey was sent to 232 UK intensive care units consisting of questions relating to fasting practices, presence of guidelines, average fasting times for common procedures and dietitian time per intensive care unit bed. RESULTS: A total of 176 intensive care units responded. Only 20% of units had guidelines and respondents stated that they were not consistently adhered to (mean compliance 66%). Units with greater dietetic involvement were more likely to have guidelines (p = 0.04). Fasting times were shorter for abdominal surgery (p = 0.002), non-abdominal surgery (p = 0.016) and radiology (p = 0.015) if a guideline was present. Fasting for extubation and tracheostomy was similar irrespective of the presence of a guideline. Considerable variation in fasting times was reported, usually due to inconsistencies in clinical decision-making. CONCLUSIONS: This survey of national practice demonstrates that fasting times are varied and inconsistent, which may lead to under-delivery of enteral nutrition. More dietetic input was associated with increased likelihood of a fasting guideline.

Alternative uses for co-products: Harnessing the potential of valuable compounds from meat processing chains.

Opportunities for exploiting the inherent value of protein-rich meat processing co-products, in the context of increased global demand for protein and for sustainable processing systems, are discussed. While direct consumption maybe the most profitable route for some, this approach is influenced greatly by local and cultural traditions. A more profitable and sustainable approach may be found in recognizing this readily available and under-utilised resource can provide high value components, such as proteins, with targeted high value functionality of relevance to a variety of sectors. Applications in food & beverages, petfood biomedical and nutrition arenas are discussed. Utilization of the raw material in its entirety is a necessary underlying principle in this approach to help maintain minimum waste generation. Understanding consumer attitudes to these products, in particular when used in food or beverage systems, is critical in optimizing commercialization strategies.

Relation between spasticity, weakness and contracture of the elbow flexors and upper limb activity after stroke: an observational study.

PURPOSE: Understanding the relationship between the motor impairments and their impact on physical activity will allow rehabilitation after stroke to be based on scientific principles. The aims of this study were to determine: (i) the relative contribution of weakness and spasticity to contracture, and (ii) the relative contribution of all three impairments to limitations in physical activity during the first 12 months after stroke. METHOD: This longitudinal observational study charted the evolution of weakness (loss of maximal force), spasticity (stretch-evoked EMG) and contracture (loss of joint range) of the elbow flexors and limitations in upper limb activity (Motor Assessment Scale) for a year after stroke in 27 subjects who had suffered a first stroke. Spasticity was measured as abnormal reflex activity, weakness was measured as loss of maximum isometric torque, contracture was measured as the difference in range of motion between the affected and intact side, and limitations in physical activity were measured on a clinical scale. RESULTS: The major independent contributors to contracture were spasticity for the first four months after stroke (p = 0.0001 - 0.10) and weakness thereafter (p = 0.01 - 0.05). However, the major and only independent contributor to limitations in physical activity throughout the year was weakness (p = 0.0001 - 0.05). CONCLUSIONS: For the first time, from a longitudinal study, the findings show that spasticity can cause contracture after stroke, consistent with the prevailing clinical view. However, weakness is the main contributor to activity limitations.

Illness representations and coping of women with chronic obstructive pulmonary disease: a pilot study.

OBJECTIVE: The purpose of this study was to explore how women recognize and respond to symptoms of chronic obstructive pulmonary disease (COPD). FRAMEWORK: The Common Sense Model by Leventhal provided the theoretic framework for the study. DESIGN: A descriptive qualitative design was used. SAMPLE: The study sample included 21 women enrolled in pulmonary rehabilitation programs. FINDINGS: The causes and consequences of COPD were these women's most prominent representations. They struggled not only with dyspnea and fatigue, but with depression, loss of social support and intimacy, and stigma. Breathing techniques, medication, rest, and avoidance measures were the most frequently used coping strategies. PRACTICE IMPLICATIONS: Because dyspnea is the central symptom, nurses must continue to teach methods to control it, as well as to search for new interventions to relieve the symptoms. Optimal levels of rest and the effect on outcomes deserve close attention. Devising ways to deal with social and psychologic isolation would also enhance coping with COPD.

Ambulatory oncology nurses making the right call: assessment and education in telephone triage practices.

Nurses in a hematology/oncology practice are responsible for the triage and management of phone calls from a diverse oncology population. An initiative was developed at the authors' institution to identify the educational needs of RNs while designing strategies to educate and improve telephone triage skills. The goal was to standardize triage practice and ultimately improve the effectiveness of telephone triage management. It was felt that these improvements could enhance the nurse-patient relationship, resulting in continuity of care to the patient, as well as reducing inappropriate appointments and hospitalizations, enhancing education, and lessening the risk of medical complications related to delays in care.

Assessment of the angiotensin-I-converting enzyme (ACE-I) inhibitory and antioxidant activities of hydrolysates of bovine brisket sarcoplasmic proteins produced by papain and characterisation of associated bioactive peptidic fractions.

The main objective was to investigate the angiotensin-I-converting enzyme (ACE-I) inhibitory and antioxidant activities of sarcoplasmic proteins isolated from the brisket muscle (Pectoralis profundus) of 3 (Bos taurus) cattle and hydrolysed with papain for 24 h at 37°C. Sarcoplasmic protein hydrolysates were ultra-filtered using molecular weight cut off (MWCO) membranes and 10-kDa and 3-kDa filtrates were obtained. The total sarcoplasmic protein extracts and the 3-kDa filtrates were tested for angiotensin I-converting enzyme inhibitory (ACE-I) activities. The total hydrolysates, 10-kDa and 3-kDa filtrates were also tested for their associated antioxidant activities using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity assay, the ferric ion reducing antioxidant power (FRAP) assay and the Fe(2+) metal chelating ability assay. The peptidic content of the total hydrolysates, the 10-kDa and the 3-kDa filtrates were analysed using an ORBITRAP mass spectrometer, and mass spectral data obtained were analysed using TurboSEQUEST. Eleven peptides were characterised from the total hydrolysates, fifteen from the 10-kDa filtrate fractions, whilst nine peptides were characterised from the 3-kDa filtrate fractions. Similarities between the amino acid sequences of the peptides identified in this study and previously identified antioxidant and ACE-I inhibitory peptides detailed in the BIOPEP database were outlined.

Isolation, purification and characterization of antioxidant peptidic fractions from a bovine liver sarcoplasmic protein thermolysin hydrolyzate.

Sarcoplasmic proteins isolated from bovine livers were hydrolyzed using the enzyme thermolysin at 37°C for 2h. The hydrolyzates were filtered through molecular weight cut off membranes (MWCO) and filtrates were obtained. The water activity (a(w)) of unhydrolysed sarcoplasmic protein, full hydrolyzates, 10-kDa and 3-kDa filtrates were below the limit necessary for microbial growth. The antioxidant activities of both filtrates and fractions were assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity assay, the ferric ion reducing antioxidant power (FRAP) assay and the Fe(2+) chelating ability assay. RP-HPLC was used for purification of the full hydrolyzates, the 10-kDa and the 3-kDa filtrates. The peptidic content of the full hydrolyzates, the 10-kDa and the 3-kDa filtrates were assessed using the Dumas method and peptide contents of each fraction were characterized using electrospray quadrupole time-of-flight (ESI-Q-TOF) mass spectrometry with the resultant spectrum analysed using the software programmes Protein Lynx Global Server 2.4. and TurboSEQUEST. Similarities between the amino acid composition of characterized peptides from each fraction and previously reported antioxidant peptides were found. This study demonstrates that meat by-product such as liver can be utilised as raw material for the generation of bioactive peptides with demonstrated antioxidant activities in vitro using the enzyme thermolysin. It is significant as it presents a potential opportunity for meat processors to use their waste streams for the generation of bioactive peptides for potential functional food use.

The N-CODES project moves to user testing.

For a technology to be implemented successfully, it must be thoroughly tested by the stakeholders who will use it in practice. This article reports on the user testing of the Nurse Computer Decision Support working prototype. Ten acute care nurses with varying levels of education and experience participated in the testing. The study's protocol consisted of a series of tasks requiring the participants to use the system while solving patient problems. Both quantitative and qualitative data on usability, ease of navigation, and nurse satisfaction were collected. The nurses ranked usability and ease of navigation highly. Nurses were excited about the system's clinical potential and felt that it would be useful to all practitioners regardless of experience. Testing the system in an actual clinical setting is the next step, but it is clear that the system has extraordinary potential to improve clinical decision making and patient outcomes.

Coupling the N-CODES system with actual nurse decision-making.

Nurses must be involved in the development and testing of clinical decision support systems if systems that fit into the actual clinical decision-making process and the flow of practice are to be designed. This article discusses the first trial of N-CODES, the Nurse Decision Support System. This system is designed to assist nurses, particularly novices, to make clinical decisions. The adequacy of the theoretical framework and selected aspects of the knowledge base were examined. Twelve nurses participated. Results indicated that revision of the theoretical framework is necessary if it is to be a fair representation of nurse's decision-making. The sequencing of information seems appropriate but the process of developing the knowledge base must be made more transparent to nurse users. After modifications, the next trial will test actual clinical use.

Breast cancer and problems with medical interactions: relationships with traumatic stress, emotional self-efficacy, and social support.

This investigation examined relationships between breast cancer patients' psychosocial characteristics (impact of the illness, traumatic stress symptoms, emotional self-efficacy, and social support) and problems they perceived in their medical interactions and their satisfaction with their physicians. Participants were 352 women enrolled in a multicenter trial of the effects of group therapy for women with recently diagnosed primary breast cancer. The findings reported here are from a cross-sectional analysis of baseline data gathered prior to randomization. Problems interacting with physicians and nurses were associated with greater levels of cancer-related traumatic stress (p < 0.01), less emotional self-efficacy for cancer (p < 0.05), less satisfaction with informational support from family, friends, and spouse, and a tendency to perceive those sources of support as more aversive (p < 0.05). Women who were less satisfied with emotional support from their family, friends and spouse were less likely to feel satisfied with their physicians (p < 0.05). These patient characteristics identify women with primary breast cancer who are likely to experience difficulty in their interactions with nurses and physicians and to be less satisfied with their physicians.

Knowledge acquisition, synthesis, and validation: a model for decision support systems.

BACKGROUND: Decision tools such as clinical decision support systems must be built on a solid foundation of nursing knowledge. However, current methods to determine the best evidence do not include a broad range of knowledge sources. As clinical decision support systems will be designed to assist nurses when making critical decisions, methods need to be devised to glean the best possible knowledge. AIMS: This paper presents a comprehensive knowledge development process to develop a nursing clinical decision support system. DISCUSSION: The Nurse Computer Decision Support Project (N-CODES) is developing a prototype for a prospective decision support system. The prototype is being constructed on rules and cases generated by the best available evidence. To accommodate the range of decisions made in practice, different types of evidence are necessary. The process incorporates procedures to uncover, evaluate, and assimilate information to develop the knowledge domain for a clinical decision support systems. Both formal and practice-based knowledge are included. The model contains several innovative approaches including the use of clinical experts and a network of practicing clinicians. CONCLUSION: These strategies will assist scientists and practitioners interested in determining the best evidence to support clinical decision support systems.