55 research outputs found
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Inclusion of the variability of model parameters on shelf-life estimations for low and intermediate moisture vegetables
Shelf-life is the time period during which products retain market-acceptable quality while meeting legal and safety requirements. Deterministic models yield single value estimations of shelf-life typically based on average or worst-case values for input parameters. In deterministic calculations, considering the input parameter variability can be challenging. In this study, a Monte Carlo procedure and the G.A.B. model for moisture sorption isotherms were used to predict shelf-life frequency distributions for intermediate moisture (IM) tomato slices, and low moisture (LM) onion flakes and sliced green beans. End of shelf-life for IM tomato slices (initial a[subscript w] = 0.8) was assumed to occur for a 10% moisture loss, and when a[subscript w] changed from 0.25 to 0.4 for LM onion flakes and LM sliced green beans. The estimated shelf-life for tomato slices, LM onion flakes, and LM sliced green beans based on the deterministic approach was 243, 86, and 79 days, respectively. The Monte Carlo procedures yielded shelf-life frequency distributions with values ranging 181â366, 76â95, and 71â90 days, respectively. Products would fail before the deterministic shelf-life value with an unacceptably high probability of 51.6, 48.6, and 53.0%, respectively. If 5% is an acceptable probability that the actual shelf-life is shorter than specified, the estimated values would be 211, 81, and 73 days, respectively. X[subscript m] and K were the most influential G.A.B parameters on the shelf-life of the three products. The package area, product amount, and water vapor transmission rate were high contributors and had the expected effect on shelf-life as demonstrated by deterministic estimations.Keywords: Monte Carlo simulations, Water activity, Moisture sorption isotherms, Shelf-life, G.A.B. model parametersKeywords: Monte Carlo simulations, Water activity, Moisture sorption isotherms, Shelf-life, G.A.B. model parameter
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Benefits and limitations of food processing by high-pressure technologies: effects on functional compounds and abiotic contaminants
The continuing and worldwide growth of pressure processing technologies to pasteurize
and sterilize foods justifies the need to study the effects on functional compounds and
nonbiotic contaminants as affected by high pressure processing (HPP) and pressureassisted
thermal processing (PATP). Substantially more research will be required to
determine the complex effects of the food matrix on chemical reactions leading to losses
of nutrients and functional components, production of toxic compounds, and to
modifications of toxic residues of chemicals used in food production or coming from
food contact materials. In PATP treatments, pressure can also increase, decrease or have
no effect on the thermal degradation rate of these substances. HPP has no major
negative and often beneficial effects on the retention of nutrients and functional
components. However, information on PATP effects is very limited and additional
research will be required before implementing this promising new technology.Keywords: polyphenols,
pressure-assisted thermal processing (PATP),
abiotic contaminants,
antioxidants,
food packaging plastic materials,
heterocyclic aromatic amines (HCAs),
acrylamide,
polycyclic aromatic hydrocarbons (PAHs),
chloropropanols,
vitamins,
nonbiotic contaminants,
pesticides,
high-pressure processing (HPP
Hydrophilic antioxidant compounds in orange juice from different fruit cultivars: Composition and antioxidant activity evaluated by chemical and cellular based (Saccharomyces cerevisiae) assays
Antioxidant capacity was evaluated by a cellular model (Saccharomyces cerevisiae) and chemical
methods (FRAP, TEAC and total phenols by Folin-Ciocalteu assay) in the hydrophilic fraction (phenolic
compounds and ascorbic acid) of orange juices (OJs) from six varieties (Midknight, Delta Seedless, Rohde
Red, Seedless, Early and clone Sambiasi), harvested in two seasons. The contents of phenolic compounds
and ascorbic acid analyzed, respectively, by UPLC and HPLC were 370.04 76.97 mg/L and
52.05 6.69 mg/100 mL. Variety and season significantly influenced (p < 0.05) composition and antioxidant
capacity. TEAC and FRAP values correlated well with individual hydrophilic compounds (R2 > 0.991) but no
correlation with cellular assay was observed. An increase in survival rates between 23% and 38% was
obtained, excepting for two varieties that showed no activity (Rohde Red and Seedless). Narirutin, naringin-d,
ferulic acid-d2, didymin, neoeriocitrin and sinapic acid hexose and caffeic acid-d1 were the phenolic
compounds which contributed to survival rates (R2 = 0.979, p < 0.01
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and lowâmiddle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of âsingle-useâ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for lowâmiddle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both highâ and lowâmiddleâincome countries
Phenolic Compounds in Mesoamerican FruitsâCharacterization, Health Potential and Processing with Innovative Technologies
Diets rich in phenolic compounds have been associated to reducing the risk of metabolic syndrome and its derived disorders. Fruits are healthy components of the human diet because of their vitamin, mineral, fiber and phenolic profile. However, they have a short shelf-life which is limited by microbiological growth and enzymatic activity. Innovative preservation methods such as high hydrostatic pressure, pulsed electric fields, ultrasound, microwave, cold plasma and ultraviolet light have become popular for the processing of fruits because they can preserve nutritional quality. In this review, the phenolic profile and health potential of 38 Mesoamerican fruits were assessed. Phenolic compounds were classified based on their contribution to the diet as flavonoids, phenolic acids, tannin, lignins and stilbenoids. Due to this composition, fruits showed a wide range of bioactivities which included anti-inflammatory, anti-diabetic, anti-hypertensive and anti-obesity activities, among others. Phenolic content in fruits submitted to innovative food processing technologies depended on parameters such as enzymatic activity, antioxidant capacity, microstructure integrity and cell viability. Innovative technologies could increase phenolic content while assuring microbiological safety by (i) promoting the release of bound phenolic compounds during processing and (ii) inducing the synthesis of phenolic compounds by activation of phenylpropanoid pathway during storage
Induced Changes in Aroma Compounds of Foods Treated with High Hydrostatic Pressure: A Review
Since conventional thermal processing can have detrimental consequences on aroma compounds, non-thermal technologies such as high hydrostatic pressure (HHP) have been explored. HHP may alter the weak chemical bonds of enzymes. These changes can modify the secondary, tertiary, and quaternary structures of key enzymes in the production of aroma compounds. This can result in either an increase or decrease in their content, along with reactions or physical processes associated with a reduction of molecular volume. This article provides a comprehensive review of HHP treatmentâs effects on the content of lipid-derived aroma compounds, aldehydes, alcohols, ketones, esters, lactones, terpenes, and phenols, on various food matrices of vegetable and animal origin. The content of aldehydes and ketones in food samples increased when subjected to HHP, while the content of alcohols and phenols decreased, probably due to oxidative processes. Both ester and lactone concentrations appeared to decline due to hydrolysis reactions. There is no clear tendency regarding terpenes concentration when subjected to HHP treatments. Because of the various effects of HHP on aroma compounds, an area of opportunity arises to carry out future studies that allow optimizing and controlling the effect
State-of-the-Art Extraction Methodologies for Bioactive Compounds from Algal Biome to Meet Bio-Economy Challenges and Opportunities
Over the years, significant research efforts have been made to extract bioactive compounds by applying different methodologies for various applications. For instance, the use of bioactive compounds in several commercial sectors such as biomedical, pharmaceutical, cosmeceutical, nutraceutical and chemical industries, has promoted the need of the most suitable and standardized methods to extract these bioactive constituents in a sophisticated and cost-effective manner. In practice, several conventional extraction methods have numerous limitations, e.g., lower efficacy, high energy cost, low yield, etc., thus urges for new state-of-the-art extraction methodologies. Thus, the optimization along with the integration of efficient pretreatment strategies followed by traditional extraction and purification processes, have been the primary goal of current research and development studies. Among different sources, algal biome has been found as a promising and feasible source to extract a broader spectrum of bioactive compounds with point-of-care application potentialities. As evident from the literature, algal bio-products includes biofuels, lipids, polyunsaturated fatty acids, pigments, enzymes, polysaccharides, and proteins. The recovery of products from algal biomass is a matter of constant development and progress. This review covers recent advancements in the extraction methodologies such as enzyme-assisted extraction (EAE), supercritical-fluid extraction (SFE), microwave-assisted extraction (MAE) and pressurized-liquid extraction (PLF) along with their working mechanism for extracting bioactive compounds from algal-based sources to meet bio-economy challenges and opportunities. A particular focus has been given to design characteristics, performance evaluation, and point-of-care applications of different bioactive compounds of microalgae. The previous and recent studies on the anticancer, antibacterial, and antiviral potentialities of algal-based bioactive compounds have also been discussed with particular reference to the mechanism underlying the effects of these active constituents with the related pathways. Towards the end, the information is also given on the possible research gaps, future perspectives and concluding remarks
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Phytochemicals and antioxidant activity of juice, flavedo, albedo and comminuted orange
Citrus fruits contain phytochemicals effective in the prevention/treatment of chronic diseases. Although many orange peel phytochemicals have been identified, information on their distribution in flavedo and albedo is incomplete limiting the development of applications for orange byproducts including comminuted orange obtained by grinding peel/juice and used in beverage formulations. Phytochemical concentration, antioxidant activity (AOA) and their relationship were determined for comminuted orange, juice and peel fractions. The highest vitamin C (74.7â98.2 mg ascorbic acid/100 g), flavones (235.9â265.0 mg hesperidin/100 g) and carotenoid (1.04â6.21 mg ÎČ-carotene/100 g) contents were found in flavedo. Albedo was the main source of phenolics (553.1â730.0 mg gallic acid/100 g), flavanones (1450.0â2084.5 mg hesperidin/100 g), and AOA (11953.2â15484.0 ÎŒmol trolox/100 g). AOA linearly correlated with phenolic, hesperidin, and flavonoid concentrations. Orange peel increased the phenolics, flavonoids and AOA of comminuted orange by 111%, 783% and 304%, respectively, when compared with juice, showing that these byproducts are a superior source of nutraceuticals.Keywords: albedo, flavedo, carotenoids, juice, flavonoids, vitamin C, phenolic compounds, comminuted orange, antioxidant activit
High Hydrostatic Pressure to Increase the Biosynthesis and Extraction of Phenolic Compounds in Food: A Review
Phenolic compounds from fruits and vegetables have shown antioxidant, anticancer, anti-inflammatory, among other beneficial properties for human health. All these benefits have motivated multiple studies about preserving, extracting, and even increasing the concentration of these compounds in foods. A diverse group of vegetable products treated with High Hydrostatic Pressure (HHP) at different pressure and time have shown higher phenolic content than their untreated counterparts. The increments have been associated with an improvement in their extraction from cellular tissues and even with the activation of the biosynthetic pathway for their production. The application of HHP from 500 to 600 MPa, has been shown to cause cell wall disruption facilitating the release of phenolic compounds from cell compartments. HPP treatments ranging from 15 to 100 MPa during 10â20 min at room temperature have produced changes in phenolic biosynthesis with increments up to 155%. This review analyzes the use of HHP as a method to increase the phenolic content in vegetable systems. Phenolic content changes are associated with either an immediate stress response, with a consequent improvement in their extraction from cellular tissues, or a late stress response that activates the biosynthetic pathways of phenolics in plants
Enzymatic Activity and Its Relationships with the Total Phenolic Content and Color Change in the High Hydrostatic Pressure-Assisted Curing of Vanilla Bean (<i>Vanilla planifolia</i>)
Diverse enzymatic reactions taking place after the killing of green vanilla beans are involved in the flavor and color development of the cured beans. The effects of high hydrostatic pressure (HHP) at 50â400 MPa/5 min and blanching as vanilla killing methods were evaluated on the total phenolic content (TPC), polyphenoloxidase (PPO), and peroxidase (POD) activity and the color change at different curing cycles of sweatingâdrying (C0âC20) of vanilla beans. The rate constants describing the above parameters during the curing cycles were also obtained. The TPC increased from C1 to C6 compared with the untreated green beans after which it started to decrease. The 400 MPa samples showed the highest rate of phenolic increase. Immediately after the killing (C0), the highest increase in PPO activity was observed at 50 MPa (46%), whereas for POD it was at 400 MPa (25%). Both enzymes showed the maximum activity at C1, after which the activity started to decrease. As expected, the L* color parameter decreased during the entire curing for all treatments. An inverse relationship between the rate of TPC decrease and enzymatic activity loss was found, but the relationship with L* was unclear. HHP appears to be an alternative vanilla killing method; nevertheless, more studies are needed to establish its clear advantages over blanching
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