Vacuum Packaging Research Articles

Vacuum Sealing Drainage against Surgical Site Infection after Intracranial Neurosurgery.

Background: Surgical site infections (SSIs) remain a conundrum for neurosurgeons. This study examines the efficacy and outcome of vacuum sealing drainage (VSD) in the treatment of pyogenic SSIs following intracranial neurosurgery. Methods: Twenty patients with SSIs, who received surgical intervention, were treated retrospectively with VSD during the past five years. Primary surgical procedure types, SSI types, VSD replacements, pathogenic germs, antibiotic therapy, and infection control were reviewed and discussed. Results: Of the 20 infections, 13 (65%) were extradural and 7 (35%) were extradural SSIs combined with intracranial infections (including 5 meningitis, 1 subdural abscess, and 1 brain abscess). All the patients consented to medical device implantation (including 5 titanium webs, 6 bone flap fixation devices, and 12 duraplasties), most of which were removed during debridement. The median duration from primary surgical procedure to an SSI diagnosis was 19 days (range: 7 to 365 d). All the patients also agreed to debridement and VSD treatment; VSD was replaced 0 to 5 times (median, one time) every 4 to 7 days and kept for 4 to 35 days (median, 14 d). Seven (35%) patients had defined bacterial infections, with Staphylococcus aureus being the dominant infection. The deployed standard VSD and antibiotic treatment ensured full recovery from SSIs, including from intracranial infections: 14 (70%) patients had recovered fully by follow-up, and no infection-associated death was registered; 6 (30%) patients died of severe primary affections. Conclusion: VSD-assisted therapy is safe and effective against SSIs after intracranial neurosurgery.

A coupled-mode analysis of mode localization on weakly-coupled silicon micromechanical resonators with damping

Mode localization on weakly-coupled silicon resonators in the areas of microelectromechanical systems (MEMS) has been widely studied for highly sensitive sensors of physical and chemical parameter monitoring. In terms of its operation principle, i.e., energy conservation, a system for the weakly-coupled silicon resonator is required to have no damping. In fact, however, various types of energy dissipation mechanisms inevitably lead to the damping even under high vacuum packaging, and for mass sensing scenarios it always operates in high damping environments. The effect of damping on the amplitude and frequency of the weakly-coupled silicon resonator is generally explored by numerical methods. Based on a weak coupling approximation, this article has developed a coupled-mode model for analytically analyzing the effects. A pair of electrostatically-coupled silicon resonator were experimentally fabricated and operated through capacitive transduction. The theoretical and experimental results show a quantitative consistency. The results presented here suggest that it may guide the design of sensors based on mode localization in the presence of damping.

Hot Carcass Fabrication Intervention for Managing Top Round Quality in Heavy Weight Beef Carcasses

Chilling-related meat quality issues have been observed in the deep portion of the top round due to the increase of average beef carcass size. The current study examines the impact of an alternative fabrication method aimed at alleviating top round quality in heavy weight beef carcasses (n = 11; 510 kg average weight). Prior to rigor, the knuckle subprimal was partially fabricated to expose the femur on alternating sides of each carcass (TRT), and each adjacent intact side served as a control (CON). All sides were air chilled (2°C) for 48 h before further fabricating. Temperature loggers placed at approximately 2.54 cm below the top round surface was the superficial (SP) location while loggers for the deep (DP) location were inserted at the midline sagittal center of the round until in contact with the femur bone. Temperature and pH decline were monitored for 48 h. The top rounds were collected, aged under vacuum packaging until 14 d postmortem, and then cut into steaks (2.54 cm). Each steak was separated into SP and DP portions and subjected to Warner-Bratzler shear force (WBSF), consumer sensory panel, and a 3-d retail display analysis which included lipid oxidation and objective color evaluation. The TRT accelerated the rate of temperature decline at the DP location (P < 0.001) and increased the pH decline rate at the SP location (P = 0.029). Retail day and location were more impactful than TRT on objective color traits. SP steaks were more tender (P = 0.001) than DP steaks. Consumer taste panel indicated TRT improved overall acceptability (P = 0.042) and flavor (P = 0.035) of top round steaks regardless of locations. TRT accelerated top round DP chilling rate and elevated steak palatability attributes. Findings of the present study report an improvement of top round steaks due to the innovative fabrication treatment.

Effects of four types of packaging on the structural characteristics, quality attributes, and antioxidant activity of foxtail millet during storage

ABSTRACT The aim of this study is to select suitable packaging for extending the shelf-life of foxtail millet grains (FMG). FMG were packaged in four types of packaging and subsequently stored at room temperature (25°C ± 1°C) for 6 months. The effects of four types of packaging on the corresponding structural characteristics, quality attributes, and antioxidant activity of FMG were investigated. The results showed that aging led to less-prominent internal morphological changes with the vacuum- and N2-packaged samples. Moreover, vacuum and N2 packaging retarded the increase of fat acidity and the decrease of yellowness (b*) during storage. Aging in cotton and polyamide–polyethylene (PA/PE) packaging resulted in less soluble solids leakage during cooking, leading to more reduction in stickiness. No changes in hardness of cooked FMG were found only for vacuum packaging. In addition, total phenolic content and antioxidant capacities were well preserved under vacuum or N2 conditions. Overall, vacuum packaging was more effective in retarding the quality deterioration of FMG when compared to the other storage conditions.

Packaging and pH Effects on Meat Discoloration through Electrochemistry

Myoglobin is the sarcoplasmic heme protein that determines the color of the meat. The oxidation state of myoglobin results in different forms of myoglobin, such as deoxy-, oxy-, and metmyoglobin. As the deviation from the bright red color of beef affects consumers' purchase decisions, meat packaging is done to retain the meat color and delay spoilage. In these studies, UV-spectrophotometric analysis is combined with the electrochemical method. Meat packaged under different conditions was considered. Two packaging conditions, vacuum and polyvinyl chloride, were compared with the normal unpackaged sarcoplasmic beef sample. Electrochemical regions of both positive and negative potential were diagnosed for sensory peaks where the data of vacuum packaging implied more color stability. To assess the effect of pH on meat discoloration, pH conditions of the physiological state (pH 7.4) and post-mortem meat (pH 5.6) were mainly considered. The rate of meat discoloration was higher at pH 5.6 than at pH 7.4. Electrochemical insights with regard to various packaging effects on meat discoloration will be discussed further.

Double Freezing Beef Strip Loin Steaks at Blast or Consumer Freezing Temperatures in Vacuum and Overwrapped Packaging

Our objective was to evaluate the combined effect of blast freezing vacuum packaged USDA Low Choice Longissimus lumborum beef steaks followed by consumer freezing of retail overwrapped steaks upon objective and subjective measures of beef palatability. The experimental design utilized a randomized complete block with a 3 × 3 treatment structure of targeted freezing treatments initially in vacuum and secondly in overwrap packaging (unfrozen = NOT; blast frozen at −34.4°C = BF; consumer-frozen at −17.8°C = CF) to accomplish 9 treatment combinations. Descriptive sensory attributes were evaluated by trained panelists on a 100-point line scale. Slice shear force and expressible moisture were assessed. Data were analyzed via PROC GLIMMIX using a randomized complete block design with a 3 × 3 treatment structure. Of descriptive panel attributes, overall juiciness was the only interaction observed (P = 0.006). Though similar to steaks initially CF in the vacuum package and followed by a second freeze (CF/BF or CF/CF) in the overwrap package, steaks singly frozen to simulate a CF (CF/NOT and NOT/CF) resulted in the overall driest ratings by panelists (P = 0.006). Only bloody/serumy differed (P = 0.002) within the initial freeze, where steaks not frozen (NOT) in the vacuum package were rated higher than those that were frozen (BF or CF). During the second freeze in the overwrap package after retail display, steaks BF rated higher for oxidized (P = 0.051) off-flavor than steaks CF and higher than both CF and NOT steaks for refrigerator-stale (P = 0.006) off-flavor; all other attributes did not differ (P ≥ 0.155). Although some freezing combinations that included CF were generally lower for overall juiciness, BF vacuum packaged steaks had no effect on palatability when compared to NOT steaks. The beef industry and consumers should feel confident using freezing as a means to extend shelf-life of beef steaks.

Phthalate migration potential in vacuum-packed fish.

Phthalates or phthalate esters (PAEs) have become a serious concern due to their toxicity and risks of migration from contact materials to food matrices and the environment. The aim of this study is to monitor the possible migration potential of PAEs in pelagic fish stored in vacuum packaging depending on the storage time and to determine the polyethylene polymers. In order to achieve this goal, sea bass (Dicentrarchus labrax) and anchovy fish (Engraulis encrasicolus) were randomly packaged in vacuum bags and then stored for 90days. Phthalate content was determined by GC/MS technique in the muscle tissue of each fish species at certain periods (0, 30, and 90days) of storage, and on the first day in the packaging material and fish meat. As a result of the analysis performed in µ-Raman spectroscopy, no microplastics were detected in both fish species' meats. FTIR spectroscopy results of the packaging material determined nylon in the chemical content of the packaging material before processing. It has been determined that the chemical composition of the packaging used in the vacuum packaging process is affected by the temperature, depending on the storage period, and different polymer types are formed in the processed package material. It was determined that the dominant PAE homologues were Di-n-pentyl phthalate (DPENP) in both fish meat and Di-(2-ethylhexyl)-phthalate (DEHP) in the package. However, during storage, Dibutylphthalate (DBP) became dominant in anchovies and DPENP became dominant in sea bass, differing according to fish species and storage time.

Effect of peeling and packaging methods on volatile compounds in pepper (Piper nigrum L.) during storage

SummaryPepper is valued for its flavour and medicinal properties, but there is a lack of comparative studies on the quality of white pepper under different storage conditions, as well as on the dynamic changes of volatiles during storage. To investigate the effects of peeling and packaging on pepper flavour and reveal the dynamic changes of volatiles, this study utilised HS‐SPME‐GC–MS to analyse the volatiles of white pepper under different peeling and packaging conditions. A total of 22 volatiles were detected, with α‐copaene, α‐terpineol, and δ‐amorphene being predominant to the volatile distinctions, while α‐copaene, α‐terpineol, and γ‐terpinene were predominant to the flavour distinctions. Mechanically peeled pepper stored in conventional packaging for 90 d or in vacuum packaging for 180 d could both uphold great quality. The flavour of manually peeled pepper stored in conventional packaging for 180 d resembled that stored in vacuum condition for 360 d.

Predicting Temperature-Dependent Aging Effects and Permanent Set of Vacuum Sealing Systems in Semiconductor Manufacturing Processes

Predicting Temperature-Dependent Aging Effects and Permanent Set of Vacuum Sealing Systems in Semiconductor Manufacturing Processes

Chemical composition of sausages processed with starter cultures Lactobacillus curvatus and Lactococcus lactis subsp. lactis during storage in vacuum packaging

Sausages belong to the category of cooked meat products with a short shelf life, which is associated with their rapid spoilage and unsuitability for consumption. One of the ways to extend the shelf life of sausages is the use of biopreservatives, including cultures of lactic acid bacteria. The aim of the study was to determine the chemical composition and organoleptic characteristics of "Juicy" sausages processed with a starter culture of Lactobacillus curvatus or a mixture of starter cultures Lactobacillus curvatus + Lactococcus lactis subsp. lactis before vacuum packaging and storage in a chilled state. Storage of sausages in the control variant in vacuum packaging in a chilled state for up to 18 days did not affect the moisture, protein, fat, and ash content, but on the 21st day, their spoilage was observed in the form of appearance of cloudy juice, sliminess, sour odor, and delamination of the vacuum packaging. Processing sausages with a starter culture of Lactobacillus curvatus or a mixture of starter cultures Lactobacillus curvatus + Lactococcus lactis subsp. lactis before vacuum packaging did not affect the moisture, protein, fat, and ash content up to 30 days of storage in a chilled state. On the 36th day, spoilage of sausages was observed in both variants of treatment with lactic acid bacteria cultures, characterized by the appearance of cloudy juice, sour odor, and delamination of the vacuum packaging. The pH value of sausages in both variants of treatment with lactic acid bacteria cultures decreased throughout the storage period and reached a level of 6.05 and 5.91 units on the 30th day. Processing sausages with either a single culture or a mixture of lactic acid bacteria cultures extends their shelf life in a chilled state by 12 days. The obtained results may justify the use of microbial biopreservatives for the production of cooked sausage products, which will help reduce losses due to spoilage during storage in vacuum packaging in a chilled state. The use of a mixture of lactic acid bacteria cultures for processing sausages requires further research and may be effective in case of detection of aerobic spoilage microorganisms.

Wafer Level Vacuum Packaging of MEMS-Based Uncooled Infrared Sensors.

This paper introduces a cost-effective, high-performance approach to achieving wafer level vacuum packaging (WLVP) for MEMS-based uncooled infrared sensors. Reliable and hermetic packages for MEMS devices are achieved using a cap wafer that is formed using two silicon wafers, where one wafer has precise grating/moth-eye structures on both sides of a double-sided polished wafer for improved transmission of over 80% in the long-wave infrared (LWIR) wavelength region without the need for an AR coating, while the other wafer is used to form a cavity. The two wafers are bonded using Au-In transient liquid phase (TLP) bonding at low temperature to form the cap wafer, which is then bondelectrical and Electronics d to the sensor wafer using glass frit bonding at high temperature to activate the getter inside the cavity region. The bond quality is assessed using three methods, including He-leak tests, cap deflection, and Pirani vacuum gauges. Hermeticity is confirmed through He-leak tests according to MIL-STD 883, yielding values as low as 0.1 × 10-9 atm·cc/s. The average shear strength is measured as 23.38 MPa. The package pressure varies from 133-533 Pa without the getter usage to as low as 0.13 Pa with the getter usage.

Effect of White Pomace Seasoning as a Natural Antioxidant for Chicken Products Packaged in Vacuum or Modified Atmosphere Conditions

Chicken breasts and burgers (88% breast and 12% backfat) were evaluated for physicochemical characteristics, thiobarbituric acid reactive substances (TBARS), and antioxidant capacity during storage in vacuum or atmosphere conditions for 18 days at 4 °C using the following two formulations: one without incorporating white pomace seasoning (WPS) and another with 3% WPS. The WPS was obtained from white grape skins, a byproduct resulting from the elaboration of white wine. The addition of the WSP decreased the L* values and increased the a* values, resulting in a significant turning toward brown tones in the chicken products. The addition of 3% of WSP led to higher values of ABTS and FRAP, regardless of the type of packaging. Both types of packaging significantly increased the levels of TBARS, although vacuum packaging proved more effective in protecting against lipid oxidation compared to modified atmosphere package (MAP). Additionally, the WSP improved the oxidative stability regarding the TBARS values. In conclusion, the WSP could be a viable alternative to chemical antioxidants and would lead to healthier and innovative chicken products.

2,3-Butanedione inhibited the swelling and microbial growth, maintained flavor and quality attributes of vacuum-packed lotus root

Swelling is a common phenomenon in the vacuum packaging of lotus root during shelf life. This study determined the primary microbial species responsible for the swelling of vacuum-packaged lotus root firstly, then, the effect of 2,3-butanedione (0.125 and 0.250 g L−1) on the swelling and quality changes of lotus root were observed. The results showed that aerogens, such as Acetobacter, Enterobacter, and Aeromonas, were the primary microorganisms responsible for vacuuming lotus root bag swelling. 0.250 g L−1 of 2,3-butanedione showed the greatest inhibitory effect on lotus root bag swelling. Furthermore, the application of 2,3-butanedione treatment could delay the appearance quality and nutritional value deterioration of the lotus root, as well as avoid rancidity and preserve the smell of the root. These findings suggest that 2,3-butanedione treatment has potential practical applications in controlling bag swelling and preserving lotus roots in vacuum packaging.

Application and Prognostic Analysis of Vacuum Sealing Drainage in the Incision Infection in Patients With Stage II-III Colorectal Cancer.

This study aims to explore the application value of vacuum sealing drainage (VSD) technology in the treatment of incision infection dehiscence after surgery in patients with stage II-III colorectal cancer and analyze its impact on prognosis. This retrospective study included patients who experienced incision infection dehiscence after surgery for colorectal cancer between February 2014 and August 2019. Clinical and pathological data, short-term outcomes, and long-term outcomes were compared between the traditional group and the VSD group. A total of 97 patients were included in this study. There was no significant difference in clinical and pathological data between the traditional group and the VSD group (P > 0.05). The VSD group had fewer dressing changes, lower pain scores during dressing changes, and better granulation tissue growth grading than the traditional group, with statistical significance (P < 0.05). The VSD group started adjuvant chemotherapy earlier and had a higher proportion of ≥4 cycles of chemotherapy. The three-year overall survival rate in the VSD group was better than the traditional group, but the difference was not statistically significant (P > 0.05). The application of VSD technology can promote granulation tissue growth, accelerate incision healing, and facilitate patients to complete subsequent adjuvant chemotherapy. However, further verification of its long-term impact on prognosis requires longer-term follow-up results.

Impact of Packaging Methods Coupled with High Barrier Packaging Loaded with TiO2 on the Preservation of Chilled Pork.

This study investigated the impact of packaging methods coupled with high barrier packaging loaded with titanium dioxide (TiO2) on the quality of chilled pork. The experiment consisted of three treatment groups: air packaging (AP), vacuum packaging (VP), and vacuum antibacterial packaging (VAP). Changes in total viable count (TVC), pH value, total volatile basic nitrogen (TVB-N) value, sensory attributes, and water holding capacity of pork were analyzed at 0, 3, 6, 9, and 12 d. TVC of the VAP group was 5.85 Log CFU/g at 12 d, which was lower than that of AP (6.95 Log CFU/g) and VP (5.93 Log CFU/g). The antibacterial film incorporating TiO2 effectively inhibited microorganism growth. The VAP group exhibited the lowest pH value and TVB-N value among all the treatment groups at this time. The findings demonstrated that the application of VAP effectively preserved the sensory attributes of pork, the hardness, cohesiveness and adhesiveness of pork in VAP group were significantly superior than those in AP group (p<0.05), but not significantly compared with VP group. On the 12 d, the CIE a* value of pork in VAP group was significantly higher (p<0.05). This exhibited that VAP could effectively maintain the freshness of chilled pork and extend the shelf life for 3 d compared to the AP group. These findings provide empirical evidence to support the practical implementation of TiO2-loaded packaging film in the food industry.

Effect of VP, MAP and combined packaging systems on the physicochemical properties and microbiological status of veal from unweaned calves

The packaging system is one of the factors influencing the preservation of the nutritional value, microbiological safety, and sensory attributes of meat. The study investigated changes in physicochemical and microbiological properties taking place during 15-day refrigerated storage of two calf muscles, the longissimus lumborum (LL) and semitendinosus (ST), packaged in three systems, respectively, vacuum packing (VP), modified atmosphere packaging (MAP, 80% O2 + 20% CO2), and a combined system (VP + MAP, 8 d in VP followed by 7 d in MAP). LL and ST stored in VP had significantly lower levels of lipid oxidation, higher α-tocopherol content, and higher instrumentally measured tenderness in comparison with the samples stored in MAP. On the other hand, the MAP samples had lower purge loss at 5 and 15 days, a higher proportion of oxymyoglobin up to 10 days of storage, and a better microbiological status. Calf muscle samples stored in the VP + MAP system had intermediate values for TBARS and α-tocopherol content and at the same time were the most tender and had the lowest counts of Pseudomonas and Enterobacteriaceae bacteria at 15 days. All packaging systems ensured relatively good quality of veal characteristics up to the last day of storage. However, for MAP at 15 days of storage, unfavourable changes in colour (a high level of metmyoglobin and a decrease in oxymyoglobin, redness and R630/580 ratio) and in the lipid fraction (a high TBARS value and a significant decrease in α-tocopherol content) were observed.

Stability and expression of K-ras mimotopes in freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder during storage in vacuum packaging.

This study aims to evaluate the storage stability of the freeze-dried recombinant Lactococcus lactis NZ3900-fermented milk powder expressing K-ras (Kristen rat sarcoma viral oncogene homolog) mimotopes targeting colorectal cancer in vacuum packaging. The freeze-dried L. lactis-fermented milk powder stored in 4-ply retortable polypropylene (RCPP)-polyamide (PA)-aluminium (AL)-polyethylene terephthalate (PET) and aluminium polyethylene (ALPE) was evaluated throughout 49 days of accelerated storage (38°C and 90% relative humidity). The fermented milk powder stored in 4-ply packaging remained above 6 log10 CFU g-1 viability, displayed lower moisture content (6.1%), higher flowability (43° angle of repose), water solubility (62%), and survivability of L. lactis after simulated gastric and intestinal digestion (>82%) than ALPE packaging after 42 days of accelerated storage. K-ras mimotope expression was detected intracellularly and extracellularly in the freeze-dried L. lactis-fermented milk powder upon storage. This suggests that fermented milk powder is a suitable food carrier for this live oral vaccine.

Emission enhancement of GaN field emitter arrays in an N2 environment

Field emitter arrays (FEAs) have the potential to operate at high frequencies and in harsh environments. However, the vacuum packaging of these devices poses a challenge due to the sensitivity of the emission phenomena to the surface properties of the cathode. Studying the effect of different residual gases on FEAs can help to understand the interaction of the emission surface with the environment and identify the feasibility and requirements for vacuum packaging. In this work, the effect of N2 exposure on 150 × 150 gallium-nitride-field emitter arrays (GaN-FEAs) was studied. The GaN-FEA was first operated at 10−9 Torr with a 1000 V DC anode voltage and a 50 V DC gate voltage, where the anode current was 6 μA. The device was then exposed to 10 000 l N2 at 10−7 Torr, and the anode current increased by 2.7 times during N2 exposure. The increase in the current was not permanent, and the current gradually decreased to its pre-exposure level after the N2 source was cut off. The results of N2 exposure were compared to Ar and O2.

The Influence of High Hydrostatic Pressure on Selected Quality Features of Cold-Storage Pork Semimembranosus Muscle.

The primary objective of this investigation was to assess the influence of high hydrostatic pressure (HHP) and the duration of cold storage on the physicochemical, technological, and sensory attributes as well as the nutritional composition and shelf life of meat. The experimental framework involved utilizing samples derived from the semimembranosus muscle of pork. Each muscle obtained from the same carcass was segmented into six distinct parts, with three designated as control specimens (K) and the remaining subjected to vacuum packaging and subsequent exposure to high hydrostatic pressure (200 MPa at 20 °C for 30 min). Comprehensive laboratory analyses of the meat were conducted at 1, 7, and 10 days post slaughter. The meat was cold-stored at +3 ± 0.5 °C. The findings of the study elucidated that the application of high hydrostatic pressure exhibited a favorable impact on the extension of the raw meat's shelf life. The tests showed a significant (p < 0.05) decrease in the total number of microorganisms compared to the control sample after 7 (K: 4.09 × 105, HHP: 2.88 × 105 CFU/g) and 10 (K: 7.40 × 105, HHP: 2.42 × 105 CFU/g) days of cold storage. It was also found that using HHP increased the pH value after 1 (K: 5.54, HHP: 5.77) and 7 (K: 5.60, HHP: 5.87) days of storage.

Effect of Essential Oils and Dried Herbs on the Shelf Life of Fresh Goat Lump Cheese.

In recent years, the use of natural preservatives in food products has gained significant attention due to their potential health benefits and effectiveness. A standardized microbiological analysis was conducted on Slovak farm-produced lump goat cheese samples to determine the antibacterial activity of dry herbs and essential oils added to vacuum-packed goat cheese. We employed five dried herbs and five essential oils derived from the same plants. The microbiological quality of 145 fresh and vacuum-packed goat cheese samples was assessed. The number of coliform bacteria, total viable count, lactic acid bacteria, and microscopic filamentous fungi were examined in raw cheese samples stored for 12 days at 4 °C. All cheese samples were vacuum-packed (control samples were packed without vacuum). This study evaluated the potential benefits of using essential oils and dried herbs from thyme (Thymus serpyllum L.), black pepper (Piper nigrum L.), clove (Eugenia caryophyllus Thunb.), mint (Mentha × piperita L.), and basil (Ocimum basilicum L.) as preservatives. The essential oils were obtained from Hanus Ltd., Nitra, Slovakia, and were applied at a concentration of 2%. The dried herbs were obtained from Popradský čaj (Poprad, Slovakia) and Mäspoma Ltd. (Zvolen, Slovakia). The results showed that all microorganism groups were significantly reduced in cheese samples following the application of essential oils throughout the entire storage period. During the preservation of cheese samples in polyethylene bags used for vacuum packing food, Lactococcus garvieae, L. lactis, Enterobacter cloacae, and Serratia liquefaciens were the most frequently isolated microbiota. Essential oils and dried herbs demonstrated antimicrobial potential during the storage of vacuum-packed goat cheese.