Antirotaviral activity of dairy byproducts enriched in fractions from hyperimmune bovine colostrum: the effect of thermal and high hydrostatic pressure treatments.

Nowadays, rotaviruses remain a major health burden, especially in developing countries, and strategies complementary to vaccination are needed. In this view, dairy fractions have attracted great scientific interest, due to their high content of bioactive compounds. The objective of this study was to evaluate the antiviral activity of whey and buttermilk enriched in proteins from hyperimmune bovine colostrum (HBC) against rotavirus. The enriched fractions were spray-dried and subsequently tested for their neutralizing activity against the bovine rotavirus WC3 strain in vitro, using differentiated Caco-2/TC7 cells. The highest antirotaviral activity was observed when whey and buttermilk were enriched in purified immunoglobulin G (IgG), showing complete rotavirus neutralization at concentrations of 3 and 6 mg mL-1 for whey and buttermilk, respectively. Additionally, the use of a crude immunoglobulin fraction also gave satisfactory results. The inhibitory activities of all samples significantly decreased after the application of heat, except for the IgG-enriched buttermilk which showed a slight increase of activity following the application of short-time treatments (75 or 85 °C for 20 s). This sample also showed a significant increase of activity (13%) after the application of low-intensity high hydrostatic pressure treatment (400 MPa for 5 min). The maximum loss of bioactivity was observed at 600 MPa for 10 min (31 and 20% for whey- and buttermilk-based formulas, respectively). This study provides relevant information on the potential of whey, buttermilk, and HBC to be part of functional products as complementary strategies to combat rotavirus infections.

Potential of CO2 laser for food processing: Applications and challenges.

Laser food processing has the breath-taking potential to revolutionize the industry in many aspects. Among the different laser configurations, CO2 laser has received special attention due to its relative high efficiency in power generation, its high-power output and its laser beam wavelength, infrared, which is strongly absorbed by water, the main component of food materials. Over the last 50 years, different uses of CO2 laser for processing foods have been proposed so far, including cooking, broiling and browning, selective laser sintering, marking, microperforation for improving downstream mass transfer operations (e.g. infusion, diffusion, marinating, salting, drying, extraction), cutting and peeling, and microbial surface decontamination. The present work is a review of the state of the art of the use of CO2 laser for food processing that covers the main characteristics and mechanisms of this technology, as well as the most important published results regarding its applications in the agri-food sector, highlighting the main challenges to bring out its full potential in the coming years.

Effect of Different Cold Storage Temperatures on the Evolution of Shucking Yield and Quality Properties of Offshore Cultured Japanese Oyster (Magallana gigas) Treated by High Pressure Processing (HPP).

High pressure processing (HPP) can improve oyster shucking yield immediately after the treatment and increase the microbiological and sensory shelf life of oysters stored at 0-4 °C. However, the evolution of shucking yield during storage has not been previously examined and there are no studies focusing on shelf life at higher storage temperatures. To elucidate both aspects, control and HPP (300 MPa; 2 min) offshore cultivated oysters (Magallana gigas) were stored at 4 and 10 °C for 14 days, analyzing shucking yield, color, texture, microbiological and sensory characteristics. HPP samples showed a higher shucking yield (17% on average) than controls with minimal impact in texture and color, regardless of storage time and temperature. At 10 °C, HPP delayed microbial growth and sensory deterioration, increasing the estimated shelf life of oysters by 3 to 4 days (aerobic plate count < 6 log cycles; overall sensory acceptability > 2). Compared to controls stored at 4 °C, HPP oysters stored at 10 °C presented the same shelf life (5 to 9 days) but with higher shucking yield (up to 25%). In conclusion, HPP is an excellent tool to increase the shucking yield and delay sensory deterioration of oysters stored at 10 °C.

Application of high-pressure assisted thermal processing (PATP) at pilot scale for replacing conventional maturation and thermal cooking in whiteleg shrimp (Litopenaeus vannamei).

BACKGROUND: The aim of this work was to examine for the first time the use of high-pressure assisted thermal processing (PATP) (100, 350, 600 MPa; 100 °C; 3 min) at pilot scale for replacing shrimp (Litopenaeus vannamei) maturation and cooking, analyzing its impact on peeling yield, color, texture and sensory properties. Shrimps subjected to conventional maturation (ice; 2 days) and thermal cooking (100 °C; boiling water, 3 min) were used as controls. RESULTS: PATP treatments at 100-350 MPa improved manual peelability over the control (P ≤ 0.05), maintaining similar peeling yield, color (L*, a*, b*), texture (shear force, shear work) and sensory properties (appearance before and after peeling, flavor, firmness; P < 0.05). However, increasing pressure to 600 MPa clearly overprocessed the samples, making it impossible to remove all the meat from the shell and resulting in a softer texture, 4.1% lower peeling yield and worse sensory quality (P ≤ 0.05). CONCLUSION: PATP (< 350 MPa; 100 °C) could be an alternative to replace conventional maturation and thermal cooking in the production of cooked shrimps, reducing processing time from days to minutes by performing both processes in a single step. © 2022 Society of Chemical Industry.

High-pressure pretreatment in albacore (Thunnus alalunga) for reducing freeze-driven weight losses with minimal quality changes.

BACKGROUND: This research evaluates the application of high-pressure processing (HPP) before freezing to reduce weight loss related to thawing and cooking of frozen albacore steaks (Thunnus alalunga) with a minimal impact on fish quality (color, texture, soluble protein, lipid oxidation). Albacore steaks were HPP pretreated (200, 250, and 300 MPa for 0, 2, 4 and 6 min), frozen (-20 °C, 5 m s-1 ), thawed (4 °C; 24 h), and then analyzed. RESULTS: At lower pressures (200 MPa) there was a clear effect of pressurization time on most of the fish quality parameters tested (thawing loss, L* value, b* value, ΔE, adhesiveness, springiness, salt-soluble protein content), whereas at higher pressures (300 MPa) similar changes took place independently of the pressurization time. High-pressure processing had no impact on lipid oxidation . A pressure of 200 MPa applied for 6 min decreased thawing, cooking, and total weight losses (53.7%, 55.4%, and 51.0% lower than the frozen control, respectively) although it led to noticeable changes in color. A pressure of 200 MPa applied for 2 min decreased thawing, cooking, and total weight losses by 23.2%, 44.0% and 33.7% with respect to the frozen control, respectively, with only minor changes in color. CONCLUSION: High-pressure processing pretreatment could be a promising tool for reducing weight loss in frozen fish when HPP conditions are properly selected. A pressure of 200 MPa applied for 2 min could be a good compromise treatment, cutting thawing and cooking losses in albacore, and reducing HPP-mediated color alterations and the related possible consumer rejection. © 2020 Society of Chemical Industry.

Olive oil pilot-production assisted by pulsed electric field: impact on extraction yield, chemical parameters and sensory properties.

The impact of the use of pulsed electric field (PEF) technology on Arroniz olive oil production in terms of extraction yield and chemical and sensory quality has been studied at pilot scale in an industrial oil mill. The application of a PEF treatment (2 kV/cm; 11.25 kJ/kg) to the olive paste significantly increased the extraction yield by 13.3%, with respect to a control. Furthermore, olive oil obtained by PEF showed total phenolic content, total phytosterols and total tocopherols significantly higher than control (11.5%, 9.9% and 15.0%, respectively). The use of PEF had no negative effects on general chemical and sensory characteristics of the olive oil, maintaining the highest quality according to EU legal standards (EVOO; extra virgin olive oil). Therefore, PEF could be an appropriate technology to improve olive oil yield and produce EVOO enriched in human-health-related compounds, such as polyphenols, phytosterols and tocopherols.

Pulsed-electric-field-assisted extraction of anthocyanins from purple-fleshed potato.

The influence of pulsed electric field (PEF) treatment on the anthocyanin extraction yield (AEY) from purple-fleshed potato (PFP) at different extraction times (60-480 min) and temperatures (10-40°C) using water and ethanol (48% and 96%) as solvents has been investigated. Response surface methodology was used to determine optimal PEF treatment and optimise anthocyanin extraction. A PEF treatment of 3.4 kV/cm and 105 µs (35 pulses of 3 µs) resulted in the highest cell disintegration index (Z(p)=1) at the lowest specific energy requirements (8.92 kJ/kg). This PEF treatment increased the AEY, the effect being higher at lower extraction temperature with water as solvent. After 480 min at 40°C, the AEY obtained for the untreated sample using 96% ethanol as the solvent (63.9 mg/100 g fw) was similar to that obtained in the PEF-treated sample using water (65.8 mg/100 g fw). Therefore, PEF was possible with water, a more environmental-friendly solvent than ethanol, without decreasing the AEY from PFP.

A new crocodylian from the late Maastrichtian of Spain: implications for the initial radiation of crocodyloids.

BACKGROUND: The earliest crocodylians are known primarily from the Late Cretaceous of North America and Europe. The representatives of Gavialoidea and Alligatoroidea are known in the Late Cretaceous of both continents, yet the biogeographic origins of Crocodyloidea are poorly understood. Up to now, only one representative of this clade has been known from the Late Cretaceous, the basal crocodyloid Prodiplocynodon from the Maastrichtian of North America. METHODOLOGY/PRINCIPAL FINDINGS: The fossil studied is a skull collected from sandstones in the lower part of the Tremp Formation, in Chron C30n, dated at -67.6 to 65.5 Ma (late Maastrichtian), in Arén (Huesca, Spain). It is located in a continuous section that contains the K/P boundary, in which the dinosaur faunas closest to the K/P boundary in Europe have been described, including Arenysaurus ardevoli and Blasisaurus canudoi. Phylogenetic analysis places the new taxon, Arenysuchus gascabadiolorum, at the base of Crocodyloidea. CONCLUSIONS/SIGNIFICANCE: The new taxon is the oldest crocodyloid representative in Eurasia. Crocodyloidea had previously only been known from the Palaeogene onwards in this part of Laurasia. Phylogenetically, Arenysuchus gascabadiolorum is situated at the base of the first radiation of crocodyloids that occurred in the late Maastrichtian, shedding light on this part of the cladogram. The presence of basal crocodyloids at the end of the Cretaceous both in North America and Europe provides new evidence of the faunal exchange via the Thulean Land Bridge during the Maastrichtian.