Herein, we discuss the modeling of the pulsed electric field (PEF) process, with attention focused on the originally intended application of pasteurization of liquid foods. We review literature on three classes of models. First are the models for electroporation (of molecular scale), derived from physics and physical chemistry considerations, and their extension to probabilistic approaches which treat pore formation as a random process. We discuss the more recent approaches involving molecular dynamics. Then, we consider treatment-chamber and system scale models, which are based on continuum physics approaches, and rely on computational Multiphysics codes for their solution. We then discuss the base assumptions for several modeling studies. Next, we consider models for inactivation kinetics for bacteria exposed to PEF, including the first order, Hulsheger, Peleg and Weibull models. We close with discussions of other models and experimental approaches for model verification and obtaining kinetic parameters from continuous flow PEF systems.
Ferroptosis is a distinct form of cell death that is driven by iron-dependent phospholipid peroxidation. Polyunsaturated fatty acids (PUFAs), particularly arachidonic acid (AA) and adrenal acid (AdA), are most prone to lipid peroxidation, which induces ferroptosis and affects the function of cell membranes. In this study, we discovered that AA induces ferritinophagy in hepatocytes, a selective form of autophagy that degrades ferritin, triggering unstable iron overload. Mechanistically, AA enhances cellular uptake of bound iron by up-regulating transferrin receptor 1 (TfR1). Additionally, AA induces endoplasmic reticulum stress (ER stress) and simultaneously activates two of its branches, pancreatic ER kinase (PERK) and inositol-requiring enzyme 1 (IRE1). Notably, PERK and IRE1 appear to play distinct roles in inducing ferritinophagy. Inhibition of PERK reduced the AA-induced increase of Fe 2+ by alleviating ferritinophagy, while inhibition of IRE1 further exacerbated ferroptosis by activating ferritinophagy. Furthermore, there seems to be an interaction between the signaling pathways of ER stress, and inhibition of IRE1 exacerbates AA-induced ferritinophagy by further activating the PERK signaling pathway, thereby exacerbating the extent of cell death. Collectively, our findings suggest that iron overload is involved in AA-induced hepatocyte ferroptosis and that this process is regulated by ER stress-mediated ferritinophagy. This study suggests potential therapeutic strategies for treating liver diseases related to lipid metabolism disorders by intervening in the ferroptosis process.
Protein has been used as the carrier for protecting and targeting polyphenols and increasing their shelf-life. Interactions of a protein molecule with polyphenols are important, which change functions and physiochemical properties of the complex and provide protection to polyphenols. Interactions between proteins and polyphenols are largely non-covalent. Factors that affect such interactions include pH, temperature, and the structure of both proteins and polyphenols. Moreover, excellent stability of polyphenols can be achieved by using nanoencapsulation techniques such as emulsion, nanohydrogel, and nanocomplex formation. The use of protein combined with other compounds such as lipids and carbohydrates was found to be the most suitable carrier for polyphenols encapsulation. This review aims to describe the interaction between proteins and polyphenols, focusing on applying nanoencapsulation for increasing stability and targeted delivery of phenolic compounds.
With the increasing demand for environmentally friendly, safe, preservative and intelligent food packaging, there is a growing trend towards using plant-derived natural colorants that posses green, non-toxic, antioxidant, antibacterial, and pH-sensitive properties. As a result, the development of active intelligent packaging films containing plant-derived natural colorants has become a research priority in the realm of food packaging. As a novel packaging approach, it can serve as an active and intelligent packaging system to prolong shelf life and monitor food quality. On the basis of introducing several widely used natural colorants derived from plants, this review examines the preparation, structural characterization, physical properties, and functional aspects of these plant-derived pigments. The preparation procedures of various film forming substrates and natural pigment based films are also comprehensively discussed. Furthermore, the utilization of natural pigment-based films as active and intelligent packaging materials in food is discussed in depth, providing valuable insights into the future development of this cutting-edge research area.
Volatile flavor has prompted a great amount of influence in acceptance and view points in fruit products. Melon ( Pyrus communis) is an aroma-dense fruit, thus, the evaluation of volatile flavor is crucial to melon-breeding. The volatile compounds present in nine varieties of Xinjiang muskmelons were identified and analyzed using the headspace solid-phase microextraction and gas chromatography-mass spectrometry methods. In addition, transcriptomics were used to discover the differential genes in fatty acid degradation pathways. It was found that a total of 170 volatile substances, including 52 alcohols, 41 esters, 24 aldehydes, 32 ketones, 14 acids and seven phenols, were identified in the nine melons. Results of PCA showed that 3-nonanol, 2-nonanol, bis (2-ethylhexyl) adipate, and 2-methylpropanal contributed more to the flavor of melon. It was verified that high activities of acyl-coenzyme A cholesterol acyltransferase (AAT) promoted the conversion of alcohols to esters, so that the melons have a high content of esters. Four genes of long-chain acyl-CoA synthetase were mainly responsible for the large difference in volatile substances. This practice may further undermine the primary rationale for the breeding and promotion in different cultivars of muskmelon.
The aim of this study was to investigate the effects of relative spatial position of stigmasterol on its photooxidation stability in different particles. Phytosterol oxidation products (POPs) from phytosterol oxidation were successfully isolated and studied using solid phase extraction (SPE) technology in conjunction with GC-MS. The photooxidation stability of stigmasterol in four particles was as follows: zein stabilized particles (ZPs) ≈ zein-pectin stabilized particles (ZPPs) > soy protein isolate (SPI)-pectin stabilized particles (SPPs) > SPI stabilized particles (SPs). 7β-Hydroxy and 5β, 6β-epoxy was the main POPs in the first and second oxidation stages, respectively, which reached 8,945 ± 43 μg/g and 6,010 ± 289 μg/g after 240 min UV light exposure treatment in SPs. When stigmasterol was hydrophobically adsorbed on the surface of SPs, the network gel generated by pectin outside SPPs prevented photooxidation of stigmasterol. When stigmasterol was encapsulated in the interior of ZPs, the blocking effect of pectin in ZPPs became insignificant. The study provided a feasible development direction for the storage and quality control of phytosterols as dietary supplements.
The current study set out to find out how shrimp quality in cold storage (4 °C) for 21 d was impacted by antimelanosic treatments (10% acerola fruit extract (AF) and 1.25% sodium metabisulphite (SMS) solutions for 10 min) in combination with modified atmosphere packaging (MAP, including vacuum): Atmospheric air (AIR), MAP1 [70% N 2 : 25% CO 2 : 5% O 2], MAP2 [25% N 2 : 70% CO 2 : 5% O 2], and vacuum (VAC). Untreated samples were considered as Control (C). Every three days, microbiological, physicochemical, and sensory investigations were conducted. Overall, the findings show that MAP improve the shelf-life of shrimp stored under 4 °C. In the battle to control melanosis, SMS's effectiveness – either alone or in combination with MAP – was overwhelming. Notwithstanding, the AF was also efficient and can be an effective and a natural substitute in the control of melanosis. When considering the results of the physico-chemical and microbiological results, the SMS often did not differ from the treatment with AF, demonstrating the excellent viability of the AF on the quality of the shrimp stored under refrigeration. However, given that acerola's high levels of vitamin C and phenolic compounds are known to have antioxidant activity, it is advised that additional studies be conducted. Preferably, these studies should aim to isolate specific fruit parts (peel, pulp, seeds) to determine where the highest concentration of phenolic compounds is found, or even to purify acerola extracts to comprehend the fruit's true antimelanosic potential.