Vacuum Storage Research Articles

Effects of adding solid and molten chocolate on the physicochemical, antioxidant, microbiological, and sensory properties of ewe's milk cheese.

A novel dairy product, namely "chocolate cheese", was produced with two typical Sicilian food products: Pecorino cheese, processed from ewe's milk, and Modica chocolate. The cheese, manufactured with 0%, 5%, 10%, and 15% (w/w) solid or molten chocolate, was evaluated after 0, 2, 4, and 6 weeks of vacuum storage for its nutritional and health properties. The addition of chocolate reduced the pH, protein, fat, and ash; the addition of 5% or 10% molten chocolate reduced hardness (N/mm2 ). The addition of either solid or molten chocolate resulted in a slight increase (P <0.1038) in the total polyphenol content, a higher oleic acid content, and less oxidative stability. The microbiological profile showed that the total mesophilic count and the number of mesophilic coccus lactic acid bacteria (LAB) were approximately equal (about 108 CFU/g) in all cheese. The survival of the microorganisms was affected by both the chocolate added and the storage time. Chocolate cheese stored for 6 weeks had less Enterobacteriaceae than control cheese, whereas yeasts were detected at higher cell densities in the former cheese. Filamentous fungi were undetectable in some cheese. Differences were also observed in the number of mesophilic rod LAB, which increased progressively over time in all cheese, and in Enterobacteriaceae, yeasts, and filamentous fungi, which decreased during storage. Descriptive and hedonic sensory tests and principal component analysis showed that fresh cheese and cheese stored for 2 weeks, including 5% molten chocolate, were the most preferred by evaluators. Based on these results, chocolate cheese has the potential to be appreciated in the market for its nutritional, health, and sensory properties. PRACTICAL APPLICATION: Chocolate cheese, made by combining two typical Sicilian foods, Pecorino cheese and Modica chocolate, is proposed as a novel dairy product. The highest sensory acceptance was obtained with the addition of 5% molten chocolate and storage for 2 weeks. Given its improved antioxidant properties, healthier fat, and sensory properties, chocolate cheese has the potential to be appreciated in the market, especially by young consumers.

Effect of Non-Condensable Gasses on the Performance of a Vacuum Thermochemical Reactor

A promising heat storage technique is based on thermochemical materials (TCM). Such materials are often used in closed systems under vacuum conditions, which is demonstrated in several projects in the European H2020 R&amp;D programs. In this type of systems, non-condensable gasses (NCG) may have a significant effect on the reactor performance. This paper considers the potential effects of NCG on vacuum TCM reactor performance in detail. Water is used as working material to study NCG. Both experiments and numerical simulations show that the effect of NCG cannot be neglected. A small amount of NCG in a vacuum setup will significantly reduce the evaporation/condensation rate. It will transform the transport process from convection-based into diffusion-based in case the pressure of NCG at the condenser surface is equal to the pressure difference between the evaporator/condenser. Designing a stable vacuum storage system, puts high demands on leak tightness of the reactors but also on avoiding NCG release originating from TCM and any used material in the reactor (like coatings and glue). Additional free volume in the reactor will help to reach the demands of stable performance over longer working periods but decreases system energy density, being a crucial KPI. With help of our model, the performance of a system can be determined.

Influence of caliper grade threshold and storage environment on the postharvest behaviour of Red Banana (AAA)

Red Banana is one of the important traditional banana varieties with unique characteristics of reddishpurple skin colour, good flavour, taste, nutrients coupled with higher export value. The study was undertaken tostandardize the harvest maturity and storage environment for the Red Banana to different market destinations.Different maturity level of (70%, 80%, 90% and 100%) Red Banana was harvested and then stored at coldtemperature (13.5ºC±1ºC) and room temperature (28.5ºC±2ºC). The observations were recorded at 10 daysinterval during storage. The results revealed that 70% maturity (40-44 mm caliper), recorded shelf life of 72 to 77days, whereas 80% maturity (44-48 mm caliper) maintained about 65-70 days, 90% maturity (48-52 mm caliper)was 57 to 62 days and 100% maturity (52-56 mm caliper) showed 32 to 40 days shelf life. At room temperature,Red Banana exhibited shelf life upto 18 days, 16 days, 14 days and 10 days at 70, 80, 90 and 100% maturityrespectively. The chroma value, pulp to peel ratio, sugar and acidity increased with the maturity whereas thefirmness and shelf life decreased. For export market, the fruits with 46-50 mm caliper with 80-90% maturitycould be harvested to have the better shelf life without compromising on the bunch weight and quality. Lowtemperature storage of vacuum packaged banana could maximize the beneficial effects without impeding thesensory quality.

Impact of Sodium Nitrite Reduction on Lipid Oxidation and Antioxidant Properties of Cooked Meat Products.

Oxidation processes are responsible for reduction of the sensory and nutritional quality of meat and meat products, thus affecting consumer acceptance. The use of sodium nitrite in meat processing is an important factor limiting these changes. Therefore, eliminating this substance from the recipe of meat products to increase their nutritional value is not an easy challenge. The aim of this study was to determine the effect of sodium nitrite reduction on the lipid oxidation (peroxide value, thiobarbituric acid reactive substances), and color parameters (CIE L*a*b*, total heme pigment and heme iron, nitrosylmyoglobin) in cooked meat products during 15 days of vacuum storage. The antioxidant properties of products and isolated peptides (2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS•), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric-reducing antioxidant power) were also evaluated. Experimental material included four different sample groups of cooked meat products produced with various percentages of sodium nitrite (0, 50, 100, and 150 mg kg−1). It was shown that the sodium nitrite dose had no statistically significant effect on lightness (L*) and redness (a*) values, as well as nitrosylmyoglobin content. Along with decreasing the share of sodium nitrite in the samples, the thiobarbituric acid reactive substances (TBARS) value increased from 0.43 mg kg−1 for samples with 150 mg kg−1 at day 0 to 3.14 mg kg−1 for samples without nitrite at day 15. The total ABTS scavenging capacity of the cooked meat samples was in the range 2.48 to 4.31 eqv. mM Trolox per g of product throughout the entire storage period. During storage, the ferric-reducing antioxidant power of samples with nitrite increased from 0.25 to 0.38 eqv. mg/mL ascorbic acid per g of product. In conclusion, reduction of nitrite to the level of 50 mg kg−1 seemed to be comparable with the traditional use of nitrite in meat products in terms of the physicochemical properties and properties related to lipid oxidation, as well as total antioxidant capacity and peptide antioxidant capacity.

Volatile and non-volatile metabolite changes in 140-day stored vacuum packaged chilled beef and potential shelf life markers

During storage of vacuum packaged chilled beef (VPCB), lactic acid bacteria become the dominant microflora, facilitating an extended shelf life. However, at some point, (bio)chemical and organoleptic changes render the meat unacceptable. In this investigation we evaluated volatile and non-volatile metabolite changes in VPCB after 84-, 98-, 120- and 140-days storage at ~ − 1 °C. After 140-days storage, the sensory, volatile and non-volatile data did not indicate spoilage. Minimal changes in volatile signatures of collected weep and on raw and grilled steaks were measured. Changes in selected non–volatile components indicated increased proteolysis (free amino acids, carnosine) and changes in organic acids (lactic, succinic) and nucleotide metabolism. Rapid volatile profiling using proton transfer reaction mass spectrometry showed a clear progression of changes in selected compounds over the storage period. An increased concentration of ethanol and other compounds between 120 and 140 days, suggested that volatile changes may be a useful objective indicator of extended storage VPCB quality.

Non-thermal inactivation of Listeria spp. in a typical dry-fermented sausage: "Bergamasco" salami.

Aim of the present study was the evaluation of the growth potential of Listeria spp. inoculated in the typical North Italian dry fermented sausage “Bergamasco” salami during its production. As it was necessary to carry out the challenge test in the production line of the industry, according to the guidelines of the European Reference Laboratory for Listeria monocytogenes, a non-pathogenic “surrogate” microorganism was used: for the inoculum, two strains of Listeria innocua (1 ATCC, 1 strain isolated from a similar substrate) were used. The inoculation of the samples occurred during grinding and mixing of the sausage mass, before the filling. To avoid cross-contamination, the control samples were produced before the contaminated ones. After the dripping, salamis were subjected to the normal production process (drying and maturation in five steps at specific temperatures and humidity rates). The inoculated products were subjected to the enumeration of Listeria spp. at T0 (day of inoculation) and at T4 (post-drying), and every 10 days during curing (T10, T20, T30, T40, T50, T60, T70, T80 and T90), as this salami is generally sold as whole piece with varying levels of curing (from T20 to T90). Since the product may be cut in half and vacuumpacked, at each of the times starting from T20, half salami was vacuum-packed and stored for 30 days at 12°C, at the end of the which Listeria spp. enumeration was performed again. At all times and for each type of samples of each of the three batches, the enumeration of the natural microflora (Total Viable Count, lactic acid bacteria, Pseudomonas spp., Enterobacteriaceae) and the determination of water activity and pH were performed on control samples. The product was characterized by a high concentration of microflora (8-8.5 Log UFC/g), consisting mainly of lactic acid bacteria, added to the mixture at the beginning of the production process. The pH showed a decrease over time, expected for this type of products, due to the development of lactic acid bacteria (final pH: 5.42-5.55). The water activity reached values able to inhibit the development of Listeria spp. (final aw: 0.826-0.863). Listeria counts in the tested batches of “Bergamasco” salami showed the absence of significant growth in the product with a reduction of loads if compared to T0, between -0.59 and -1.04 Log CFU/g. Even in the samples subjected to vacuum packaging and storage at 12°C, the absence of significant increase of lactic acid bacteria in the product was highlighted with further decrease of bacterial loads (-0.70/-0.79 Log CFU/g if compared to T20). Considering the worst case scenario (thus the batch with the highest growth potential), in the products stored in the curing room at 14-16°C, at humidity of 80% and in the samples stored at 12°C and vacuum packaged, the threshold indicated by the EURL Lm guidelines (+0.5 Log CFU/g) for the growth of Listeria spp. was not reached, allowing to classify “Bergamasco” salami in the category 1.3 of the EC Reg. 2073/2005 as “Ready-to-eat food unable to support the growth of Listeria monocytogenes”.

Proposal Solar Drying With Heat Storage Applied to Medicinal Plants

In this work, a proposal of an indirect solar dryer with a vacuum solar collector and storage of water-sensitive heater is presented. A mathematical model is presented as the first approximation to evaluate the performance. The test climatic conditions are based on the city of Cascavel (Paran&amp;aacute;, Brazil) and the resolution of the model was aided by the EES program. In order to analyze the performance of the system, a model load was created based on the references found in the literature, sample of 80 kg with initial water content of 75% w.b and final of 10% w.b, for drying time of 4 h and 3 h with air velocity of 0.7 m/s and 1.1 m/s respectively. It was possible to simulate the variation of the temperature of the reservoir during the day, as well as the response of the heat exchanger to the variation of temperature of entrance of the fluids and the climatic influence, radiation and ambient temperature in the participation of the solar energy in the total energy consumption of the drying. The simulations suggest good results with solar fraction between 20 and 47 %, meanwhile in the literature the values reported are between 10 and 25%.

Process optimization and stability characterization of the bio-oil produced from vacuum pyrolysis of rape straw

ABSTRACT Rape straw, as a typical residue from agriculture, was recycled to produce bio-oil via vacuum pyrolysis. The energy conversion rate (ECR) of biomass pyrolysis was proposed to take into account the impacts of process factors on both bio-oil yield and calorific value. Response surface methodology was employed to investigate the interactions of factors, and the highest ECR of 34.5% was obtained at the pyrolysis temperature of 466.7°C, reactor pressure of 5.0 kPa, and heating rate of 20.0/min. The bio-oil production in this study reflected certain potential and advantages. Moreover, the bio-oil was treated by vacuum distillation and storage aging, and the composition changes were characterized. Bio-oil was a complex mixture consisting of various organics, and the strenuous exercise of electrons in the functional groups existed in the treatments so that the interactions between organics were intensified, and all fractions from bio-oil belonged to the polydisperse system.

Investigation of the applicability of the ESR nail dosimetry for assessment of accidental exposure in medical facilities

The study of human fingernails as a possible dosimeter has continued to be of interest in the field of accident dosimetry because of its potential advantages. The present study aims to investigate the suitability of fingernails for the assessment of accidental exposure in medical facilities that use radiation for diagnosis or radiation therapy through the electron spin resonance (ESR) dosimetry technique. Relevant drying conditions, sample characteristics, and setup modifications were tested and compared among the samples of three different individuals. Results indicated that 1 h of sample drying inside a heat dryer sterilizer at 100 °C temperature showed good thermal stability of the ESR signals up to 30 days of postmeasurement. Another finding of this study was the effective approach in the signal stability for samples kept under vacuum storage condition with limited exposure to ambient light. While the samples from three different individuals showed unique dose–response curves after the X-ray irradiation, those were quite linear in the therapeutic dose range (up to 70 Gy). These results indicate that fingernails could be useful for the detection of unexpected significant exposure of patients and medical staff handling radiation or radiopharmaceuticals. Further investigations are desirable for standardization of the fingernail dosimetry in medical applications.

Inhibition of Listeria monocytogenesin deli-style Turkey using hop acids, organic acids, and their combinations

This study was conducted to evaluate antilisterial activity in deli-style turkey using one of the inhibitors: hop α- or β-acids at 5ppm, potassium acetate/potassium diacetate (PAPD) at 0.5%, their combinations, potassium lactate/sodium diacetate (PLSD) at 2.5% for positive control, and ethanol at 5ppm for negative control. Deli-style turkey was formulated and manufactured traditionally. To simulate Listeria contamination in processing plants, the deli turkey was sliced in <24h of production, inoculated with Listeria monocytogenes (2 to 3 log CFU/g), and vacuum-stored at 4 or 7°C for 60 d. To simulate Listeria contamination in grocery stores, the deli turkey was vacuum-stored for 30 and 60 d prior to slicing, inoculation, and aerobic storage at 4 or 7°C for 10 d. Physicochemical properties of the deli turkey were not significantly different among treatments (P > 0.05). Addition of hop acids at 5ppm did not inhibit Listeria in deli meat during 60 d of vacuum-storage at 4 or 7°C, whereas organic acids and hop acids/PAPD significantly inhibited Listeria (P < 0.05), with the best inhibition observed for hop β-acids/PAPD at 7°C/60 d. During 10 d of aerobic storage at 4°C, hop acid/PAPD, PLSD, or PAPD showed listeristatic effects, whereas hop acids alone allowed Listeria to grow by 0.9 CFU/g. During 10 d of aerobic storage at 7°C, hop acid/PAPD, PLSD, and PAPD significantly reduced Listeria populations than hop α-acids, β-acids, and no-inhibitor control (P < 0.05). These results indicated the combination of hop β-acids/PAPD provides more effective inhibition than any single addition of hop acids and PLSD (P < 0.05) at 7°C/60 d in vacuum storage, with intermediate inhibition observed for PAPD and α-acids/PAPD.

Effect of ethyl-lauroyl-arginate hypochloride in combination with high hydrostatic pressure processing on the microbial load and physico-chemical characteristics of minced and portioned chicken breast meat.

Campylobacter is an important hazard responsible for many human gastroenteritis cases. As poultry meat is the main source of Campylobacter, many approaches to reduce the Campylobacter load in this meat have been published. In the present study minced and whole broiler breast meat samples were inoculated with Campylobacter (C.) jejuni and treated with different concentrations of the food additive ethyl-Nα-lauroyl-L-arginate hypochloride (LAE, 1,000/1,500 ppm (minced meat); 400/1,000 ppm (whole meat)), with high hydrostatic pressure (HPP, 100/ 200 MPa) or a combination of both preservation methods, followed by vacuum storage up to day 14 after treatment. Aim of the study was to analyze if effects of LAE and HPP alone and in combination on the C. jejuni concentrations and on different meat quality parameters could be found. Analysis of minimal inhibitory and minimal bactericidal concentrations (MIC, MBC) of LAE against 11 C. jejuni and five C. coli strains resulted in MIC/ MBC of 32 ppm for 12 and 64 ppm for four strains investigated. Only 1,500 ppm LAE in minced meat resulted in a significant reduction of the C. jejuni concentrations directly after treatment (day 1) and on day 7 compared to the untreated control samples. Treatment of whole breast meat with 400 and 1,000 ppm LAE resulted in significantly lower C. jejuni concentrations on days 1, 7, and 14 compared to control samples. However, HPP alone and in combination with LAE was not able to reach significant microbial reduction. Whereas LAE only slightly influenced the lightness (L*) results of the minced meat (day 1), HPP treatment with 200 MPa generally increased the L* and yellowness (b*) results of the minced and whole meat on day 1. During further storage, color results were inconsistent in minced and whole meat samples, as well as the myoglobin redox form percentages in the whole meat. In conclusion, a synergistic effect of LAE and HPP could not be proved using the chosen concentrations of LAE and pressure values.

Development of Instant Microbial Starter for Production of Fermented Cassava Flour: Effect of Vacuum Drying Temperature, Carrier Media, and Storage Temperature

Cassava is an important crop for tropical countries such as Nigeria, Brazil, Thailand, and Indonesia. The potential utilization of cassava in the food industry can be enhanced by processing cassava into fermented cassava flour (fercaf), which has been shown to have a neutral color and aroma as well as low cyanogenic content. The use of specific microbial starter in the cassava chip fermentation for fercaf production will direct the fermentation process, maintaining a high quality of the produced flour. Thereby, the availability of an easy-to-use microbial starter is important for the production of fermented cassava flour. The aim of this study was to evaluate vacuum drying methods in the preparation of microbial starter for fermented cassava flour production. In particular, the effects of carrier media, drying and storage temperature on cell viability in dry starter were tested. The results showed that different methods should be applied to different microbial species. Bacillus subtilis and Aspergillus Oryza should be prepared using fercaf as the carrier media at a drying temperature of 55 °C, whereas Lactobacillus plantarum starter should be prepared using skim milk as the carrier media at a drying temperatur of 40°C. Apart from B. subtilis, the starters should be stored in a refrigerator.

A self-digitization chip integrated with hydration layer for low-cost and robust digital PCR

We present a self-discretization and zero-water-loss microfluidic digital PCR (dPCR) device to enable low-cost and robust quantitative nucleic acid assays. In this device, a thin void is integrated beneath the reaction chamber array. By utilizing the permeability of polydimethylsiloxane (PDMS) film, the integrated void serves a dual function: vacuum “accumulator” and hydration “reservoir”. The combination of pre-stored pumping energy and water compensation for evaporation loss enables simple, robust and reliable single-DNA-molecule amplification and detection in 10,000 reactors of picoliter volume. Compared to the conventional degassing PDMS pumps, the vacuum accumulator exhibits superior performance due to more vacuum storage and shorter diffusion distance. We also evaluated the performance of the embedded hydration layer in suppressing evaporation loss at elevated temperatures, and verified that zero-water-loss could be achieved for all reaction chambers in our dPCR chip during thermal cycling. By performing quantitative detection of T790M DNA from 10 to 104 copies/μL, the proposed dPCR chip demonstrated high accuracy and excellent performance for the absolute quantification of the target gene with a dynamic range of 104. The simplicity and robustness of our dPCR chip make it well suited for low-cost molecular diagnostic assays under resource-limited settings.

Microbial changes and aroma profile of nitrate reduced dry sausages during vacuum storage

Slow fermented sausages with reduced ingoing amounts of sodium nitrate (control, 15% and 25% reduction) were stored under vacuum up to three months. Changes in microbiology, chemical parameters and volatile compounds were studied. Residual nitrate was not affected by vacuum storage and its reduction resulted in a reduction of sausage redness. General microbial counts decreased during vacuum storage, though nitrate reduction increased the growth of total mesophilic bacteria and Gram positive cocci. Long storage time and 25% nitrate reduction affected microbial activity and sausage aroma profile. Short vacuum storage times and moderate nitrate reduction (15%) were related to compounds producing pleasant odours (3-hydroxy-2-butanone, ethyl octanoate, ethyl-3-methylbutanoate and 2,3-pentanedione) and cheesy/buttery odour (2,3-butanedione and ethyl-2-hydroxypropanoate). In contrast, 25% nitrate reduction increased compounds like heptanal (green, unpleasant odour) and those related to unpleasant odours, methanethiol (rotten odour) and methional (cooked potato).

Production of chicken sausage (Cobb 500 (Smith, 1992)): caracterisation of Physicochemical, microbiological and sensorial qualities.

The aim of this work is to produce chicken sausage, hence, increasing the added value of chicken. The physicochemical and sensorial qualities were evaluated. Microbial quality was investigated during a period of one month under vacuum storage conditions at 4°C. From the results, it appears that the physicochemical parameters of chicken meat before processing and chicken sausage showed a significant (p&lt;0.05) difference. The chicken sausage compared to the chicken meat, presents good physicochemical characteristics (an acidic pH of about 5.1, a lowered water content of 67.33 ± 0.76 % to 60.00 ± 0.87% and a relatively high water retention capacity from 28.85 ± 1.46% to 69.24 ± 0.52%) for its better preservation. The microbiological quality of chicken sausage was studied over a period of four weeks under one storage condition (4°C) and showed that the chicken sausage is fairly safe for consumers compared to the recommended levels (absence of salmonella, a total mesophilic aerobic flora of 2.6.103 ± 3.8.102 CFU/g of product, a rate of Staphylococcus aureus, Escherichia coli respectively 2.05.101±3.2 and 6.8±3.2 CFU/g of product) after four weeks chilling storage. The chicken garlic sausage was the best sample appreciated by consumers organoleptically with a percentage of 77.02%. Therefore, processing of chickens in chicken sausage can be a technological center to explore.

Marination and cooking performance of portioned broiler breast fillets with the wooden breast condition.

The wooden breast (WB) condition in broiler breast meat negatively influences technological meat quality. However, it is unknown if the WB effects are uniform throughout the Pectoralis major. The objective of this study was to determine the effects of WB on the marination and cooking performance of the dorsal and ventral portions of broiler breast fillets. Sixty butterfly breast fillets were collected from the deboning line of a commercial plant and sorted into normal (no WB) and severe WB categories. Each fillet was horizontally portioned into dorsal and ventral halves. Portions from one side of each butterfly were used as non-marinated controls, while portions from the other side were vacuum-tumble marinated (16rpm, -0.6 atm, 4°C, 20min) with 20% (wt/wt) marinade to meat ratio. Marinade was formulated to target a final concentration of 0.75% salt and 0.45% sodium tripolyphosphate in the final product. Samples were cooked to 78°C in a combination oven. Marinade uptake and retention were lower (P < 0.001) in both the ventral and dorsal portions of the WB fillets. The dorsal portions had greater (P < 0.001) marinade uptake and retention than the ventral portions in both normal and WB fillets. For non-marinated samples, cook loss was greater (P < 0.05) in both the ventral and dorsal portions of WB fillets. In marinated samples, however, cook loss was similar between the dorsal portions of normal and WB fillets. Final cooked product yield was calculated based on pre-marination and post-cook weights. Non-marinated WB samples exhibited lower (P < 0.001) cooked product yields than normal samples in both portions. For marinated samples, cooked product yields were greater (P < 0.001) in the dorsal portions. Data demonstrated that the dorsal portion of the Pectoralis major more readily absorbs and retains marinade during vacuum tumbling and storage than the ventral portion. Although the WB condition negatively influenced marination and cooking performance in both fillet portions, the effects were less severe in the dorsal portion.

The effect of increased methionine in broiler chicken diets on the quality of breast muscles at different times of vacuum storage under refrigeration

The aim of the study was to determine the effect of different levels of DL-methionine in feed for broiler chickens on the quality of vacuum-packed breast muscles stored under refrigeration. The material for the study was 72 breast muscles from 35-day-old broiler chickens fed diets with varying content of DL-methionine. The control group received a basal diet without additional DL-methionine, while the experimental groups received compound feeds supplemented with 0.08% or 0.24% DL-methionine. At 35 days of age, 24 birds from each group were randomly selected and experimentally slaughtered. After the carcasses were dissected, 8 right breast muscles were selected from each feeding group and analysed immediately after cooling. The remaining muscles were vacuum-packed and after 7 and 14 days of storage physicochemical and sensory analyses were performed to assess the influence of storage time on changes in their quality. The methionine level was not found to affect the sensory properties of the breast muscles, but the meat of birds receiving a higher level of this amino acid had better shear force and water-holding capacity in comparison to the control group. After just 7 days, the results of the analyses of vacuum-packed refrigerated muscles showed a negative effect of storage time on the capacity of the muscle tissue to bind water, as well as changes in the proportion of red colour in the muscles. However, it is worth noting that the sensory quality of the muscles deteriorated only after 14 days of storage.

Technological characteristics of pre- and post-rigor deboned beef mixtures from Holstein steers and quality attributes of cooked beef sausage

The objective of this study was to determine the effects of deboning time (pre- and post-rigor), processing steps (grinding - GB; salting - SB; batter formulation - BB), and storage time on the quality of raw beef mixtures and vacuum-packaged cooked sausage, produced using a commercial formulation with 0.25% phosphate. The pH was greater in pre-rigor GB and SB than in post-rigor GB and SB (P < .001). However, deboning time had no effect on metmyoglobin reducing activity, cooking loss, and color of raw beef mixtures. Protein solubility of pre-rigor beef mixtures (124.26 mg/kg) was greater than that of post-rigor beef (113.93 mg/kg; P = .071). TBARS were increased in BB but decreased during vacuum storage of cooked sausage (P ≤ .018). Except for chewiness and saltiness being 52.9 N-mm and 0.3 points greater in post-rigor sausage (P = .040 and 0.054, respectively), texture profile analysis and trained panelists detected no difference in texture between pre- and post-rigor sausage.

Safe transportation of formalin-fixed liquid-free pathology specimens.

Diagnostic pathology activities are largely based on fixation of tissues in 4% formaldehyde, which has recently been re-classified as a carcinogenic compound and banned in several countries. Hospitals that do not have in-house pathology services need to send surgical and biopsy specimens to referral centers. These are generally transferred in liquid containers, under suboptimal safety conditions, as accidental spillage of potentially dangerous substances may occur. A safe, innovative, two-step procedure for pathology sample transportation is presented. Formalin-fixed material from ten surgical cases was dissected (including surrogate biopsies) and preserved in liquid-free plastic bags under vacuum for up to 30days and subsequently processed for conventional histology, several immunohistochemical markers, and molecular tests (e.g., RAS mutation). The data were compared with the corresponding routine analyses. Formalin-fixed specimens after up to 30days under vacuum storage gave equivalent results compared to standard histopathological slides and molecular tests, regarding both hematoxylin-eosin, immuno-stained slides and also nucleic acid extracted for molecular tests. The proposal of under-vacuum sealing pathology specimens that were previously formalin fixed can be adopted to transfer liquid-free biopsy and surgical specimens to referral pathology services. In fact, it is easy to perform, less expensive (both plastic bags and domestic-type vacuum chamber machines are at affordable costs), and above all is fully safe and adequate in the pre-analytical processing of pathology specimens.

Defects and Low-Frequency Noise in Irradiated Black Phosphorus MOSFETs With HfO2Gate Dielectrics

We have evaluated radiation-induced charge trapping and low-frequency noise in passivated black phosphorus (BP) MOSFETs with HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> gate dielectrics. Thinning the gate dielectric reduces total ionizing dose-induced threshold voltage shifts. The defect-energy distribution estimated from low-frequency noise measurements performed as a function of temperature decreases with increasing energy in as-processed devices. Local maxima in noise magnitude are observed in irradiated devices at activation energies of ~0.2 and ~0.5 eV. Larger defect-related peaks in noise magnitude in the range of 0.35-0.5 eV are observed after biased post-irradiation annealing, and/or vacuum storage of the devices after irradiation and annealing. Density functional theory calculations strongly support significant roles for O vacancies in HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> and H+ transport and reactions near the BP/HfO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> interface in the observed radiation response and low-frequency noise.