Measurement of slight pH variation in food samples is valuable for assessing food freshness and quality. Herein, a novel colorimetric and near infrared (NIR) fluorescent probe, Hx, was developed to measure slight pH variation in various food samples. Probe Hx showed fluorescence response to pH in the NIR fluorescence region. Moreover, based on the unique transformation of the ring-opened form and ring-closed form, probe Hx displayed highly sensitive response to slight pH variation (0.1–0.2 pH units) near neutral pH. Also, probe Hx exhibited obvious colorimetric changes to pH. Probe Hx has been applied for accurately detecting pH in freshly squeezed juices. Importantly, upon fabricating the test paper, probe Hx was employed as a simple and sensitive tool to on-site monitor slight pH variation in packed meat in the process of spoilage. Additionally, upon detecting slight pH variation in potato tissues, the probe could be served for assessment of potato infected by silver scurf.

Hempseed (Cannabis sativa L.) is currently being investigated for its health-promoting properties acting as antioxidant and anti-inflammatory agents. Here, we present a modified protein isolation method of producing hempseed protein isolate from industrial hempseed hearts (HPI-12) using pH 12. In addition, bromelain was used to hydrolyze HPI-12 (BHPI-12) to determine the effect on functionality and bioactivity. HPI-12 is a rich source of essential amino acids with low protein solubility, effective in reducing 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals without oxygen radical antioxidant capacity (ORAC). Further, HPI-12 reduced pro-inflammatory IL-6 and TNF-α cytokines in lipopolysaccharide-induced inflammation in THP-1 macrophages. Upon hydrolysis, protein solubility was improved accompanied by modified water- and oil-holding capacities. BHPI-12 was more effective at quenching DPPH radicals with improved ORAC. BHPI-12 showed an improved ability to reduce IL-6. We report for the first time the ability of both HPI-12 and BHPI-12 as potential functional food ingredients with antioxidant and anti-inflammatory activity.

For solubilizing the flavonoid Quercetin (Qct), many mediums are adopted. Surfactant solubilization is important among them. In this work, the interaction of Qct with three nonionic tween surfactants, viz., Tween 20, Tween 40, and Tween 80 was investigated. The effect of the length of the carbon chain on the interaction was analyzed by conductometry, infrared spectroscopy, UV–visible spectroscopy, and antioxidant studies. The experimental results suggested that Tween 80 was most efficient out of the three tween surfactants taken for the study. From the conductivity studies the counterion binding constant β was used to calculate various thermodynamic parameters like Gibbs free energy, ΔG0m, enthalpy, ΔH0m, and entropy of micellization, ΔS0m. The order of stability is given as Qct-Tween 80 > Qct-Tween 20 > Qct-Tween 40. The theoretical values also corroborate the same order of interaction with the three surfactants.

Many photoinduced excited states’ relaxation processes and chemical reactions occur at interfaces and surfaces, including charge transfer, energy transfer, proton transfer, proton-coupled electron transfer, configurational dynamics, conical intersections, etc. Of them, interactions of electronic and vibrational motions, namely, vibronic couplings, are the main determining factors for the relaxation processes or reaction pathways. However, time-resolved electronic-vibrational spectroscopy for interfaces and surfaces is lacking. Here we develop interface/surface-specific two-dimensional electronic-vibrational sum frequency generation spectroscopy (2D-EVSFG) for time-dependent vibronic coupling of excited states at interfaces and surfaces. We further demonstrate the fourth-order technique by investigating vibronic coupling, solvent correlation, and time evolution of the coupling for photoexcited interface-active molecules, crystal violet (CV), at the air/water interface as an example. The two vibronic absorption peaks for CV molecules at the interface from the 2D-EVSFG experiments were found to be more prominent than their counterparts in bulk from 2D-EV. Quantitative analysis of the vibronic peaks in 2D-EVSFG suggested that a non-Condon process participates in the photoexcitation of CV at the interface. We further reveal vibrational solvent coupling for the zeroth level on the electronic state with respect to that on the ground state, which is directly related to the magnitude of its change in solvent reorganization energy. The change in the solvent reorganization energy at the interface is much smaller than that in bulk methanol. Time-dependent center line slopes (CLSs) of 2D-EVSFG also showed that kinetic behaviors of CV at the air/water interface are significantly different from those in bulk methanol. Our ultrafast 2D-EVSFG experiments not only offer vibrational information on both excited states and the ground state as compared with the traditional doubly resonant sum frequency generation and electronic-vibrational coupling but also provide vibronic coupling, dynamical solvent effects, and time evolution of vibronic coupling at interfaces.

Spoiled food, especially seafood, poses a huge challenge to food safety and human health, which should be addressed through early monitoring and warning of freshness. Despite the fact that several food colorimetric sensors have been reported recently, only a small number of them can match the demands of easy manufacturing, high sensitivity, and satisfactory reliability. Herein, we report a type of dual-color ratiometric composites as fluorescent sensors (DUCS) with good processability, which offers the superior real-time and visual detection of seafood spoilage. A visually detectable colorimetric sensitivity under portable UV light irradiation has been achieved for seafood stored at room temperature for 4–6 h (response time variable with different food ingredients). Moreover, the ease and versatility of our formulation, composed of organic fluorophores, polymers, and additives as composites, has enabled facile processing, including drop-coating and stamp-patterning, which would facilitate a broad scope of applications for food sensing and beyond.

This study aimed to investigate the changes in the pecan kernel color, carotenoids, polyphenols, and physicochemical properties during five months of storage at room temperature for five different pecan varieties. The results showed that the pecan kernel color darkened with a shift toward more red and less yellow during the storage. Additionally, the dorsal side of the kernel had a lighter color than the ventral side. Total carotenoids deceased from 92.0–118.8 to 45.2–101.9 μg/100 g of whole kernel, while total polyphenols had no significant differences (18.1–27.0 mg of GAE (gallic acid equivalent)/g of whole kernel) commonly. Three phenolics (gallic acid, catechin, and ellagic acid) were of 6.7–9.6, 31.4–46.7, and 11.7–16.2 mg/100 g of whole kernel and increased during storage. The pecan kernel moisture loss was significant, while the total lipids remained unchanged. Five texture parameters (hardness, toughness, slope, fracturability, and break) showed irregular changes. Genotypic variation was observed in all five varieties, although the storage was the main factor affecting the compositions.

Plant polyphenols’ antibacterial capabilities are just beginning to be applied in the environment. In this study, solvent recovery and concentration techniques were used to achieve zero-waste extraction of pineapple peel polyphenol (PPP) powder on an industrial scale. For environmental sterilization, PPP antibacterial agents (PAAs) were created. Their physicochemical and antibacterial qualities were examined, and technical and financial analysis was done. The results showed that (1) among the major PPP components, protocatechuic acid content was the highest (48.90 mg/L), followed by quercetin dihydrate (17.56 mg/L); (2) PAA sprays passed the tests for physicochemical properties like pH and heat resistance; (3) at the 8 mg/mL concentration, PAA achieved 100% bacterial inhibition below 40 °C; and (4) the production cost of 8 mg/mL PAA spray was only $273.41/t at 100,000 t industrial scale. These findings might offer an application prospect in the development of renewable bacteriocins from fruit and vegetable waste materials.

Sustainability, circularity, and Zero Waste policies are timely concepts for policy development and strategies in the European Union (EU) and other global regions. Insects can likely become key players in the bioconversion of waste to valuable material and promise one solution to achieve diverse societal goals. Insects further present strategic opportunities as food products; however, it is necessary to understand how insects accumulate and eliminate priority contaminants from different substrates where they can be reared. In the present study, we expanded beyond previous work with mercury (Hg) to examine bioaccumulation kinetics in Tenebrio molitor (YMW) and Hermetia illucens (BSF). Two-phase bioaccumulation assays, with an uptake (contaminated Hg substrate) and elimination phase (clean substrate), followed by toxicokinetic modeling, showed that both insects have a high capacity to regulate Hg, often reaching an internal steady-state concentration at level responding on the substrate concentration of Hg. Of importance for product safety, both insects quickly eliminated Hg after being transferred to clean substrate. Specifically, BSF eliminated half of the accumulated Hg in approximately 1 day (after 5 days of Hg exposure) and YMW in 4–5 days (after 21 days of Hg exposure). These results provide crucial product safety information for insect producers using possibly contaminated substrates, specifically informing the amount of time for Hg depuration prior to processing and commercialization for food and feed.

In iron-fortified bouillon, reactivity of the iron ion with (acylated) flavone glycosides from herbs can affect product color and bioavailability of iron. This study investigates the influence of 7-O-glycosylation and additional 6″-O-acetylation or 6″-O-malonylation of flavones on their interaction with iron. Nine (6″-O-acylated) flavone 7-O-apiosylglucosides were purified from celery (Apium graveolens), and their structures were elucidated by mass spectrometry (MS) and nuclear magnetic resonance (NMR). In the presence of iron, a bathochromic shift and darker color were observed for the 7-O-apiosylglucosides compared to the aglycon of flavones that only possess the 4–5 site. Thus, the ability of iron to coordinate to the flavone 4–5 site is increased by 7-O-glycosylation. For flavones with an additional 3′–4′ site, less discoloration was observed for the 7-O-apiosylglucoside compared to the aglycon. Additional 6″-O-acylation did not affect the color. These findings indicate that model systems used to study discoloration in iron-fortified foods should also comprise (acylated) glycosides of flavonoids.

Biodegradable food packaging is an important area to be focused on in preserving food. A biopolymer-based film was prepared with hybrid nanoparticles (TiO2 + ZnO) mixed with pomegranate peel powder (PPP) electrospin-coated over an aluminum foil. Morphological analysis of the hybrid nanoparticles along with PPP was performed using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The diffuse reflectance spectroscopy study exemplified that the coated film was UV-protective. Cooked chapattis were stored in coated and noncoated Al foil. Experimental rancidity and hydroperoxide (6th day: 2.85 ± 0.14) values exemplified that chapatti in the coated film lasted for four more days compared to that in the noncoated film. The antioxidant and antibacterial effects of the active mixture over chapattis were analyzed using thiobarbituric acid reactive substance and 2,2 diphenyl-1-picrylhydrazyl assays. The effective reduced bacterial load on chapattis stored in the coated film on the 6th day was estimated to be 3.1 × 103 cfu/mL and observed to be minimal. The present work establishes a novel active mixture that could be used as a coating in active food storage.

Purple potatoes were dehydrated with a combination of low relative humidity air flow at room temperature and ultraviolet (UV)-A light exposure. The control, dehydrated purple potatoes without UV-A light exposure contained approximately 133% more moisture wet basis than their UV-A light-treated counterparts, which resulted in the removal of 97% of the original mass of water in the UV-A light-treated potatoes. Electron microscopy and infrared spectroscopy analyses confirmed substantial preservation of the physical and chemical integrity of the UV-A light-dehydrated samples even under prolonged storage within a wide range of RH levels (11.3–86%). The UV-A light-dehydrated purple potatoes also preserved to some extent their original color without the need of pretreatments for enzyme inactivation and had significantly higher total phenolics concentration than the raw samples. Differential scanning calorimetry confirmed the preservation of physical integrity through its association with thermal properties.

Paramagnetism in solid-state materials has long been considered an additional challenge for structural investigations by using solid-state nuclear magnetic resonance spectroscopy (ssNMR). The strong interactions between unpaired electrons and the surrounding atomic nuclei, on the one hand, are complex to describe, and on the other hand can cause fast decaying signals and extremely broad resonances. However, significant progress has been made over the recent years in developing both theoretical models to understand and calculate the frequency shifts due to paramagnetism and also more sophisticated experimental protocols for obtaining high-resolution ssNMR spectra. While the field is continuously moving forward, to date, the combination of state-of-the-art numerical and experimental techniques enables us to obtain high-quality data for a variety of systems. This involves the determination of several ssNMR parameters that represent different contributions to the frequency shift in paramagnetic solids. These contributions encode structural information on the studied material on various length scales, ranging from crystal morphologies, to the mid- and long-range order, down to the local atomic bonding environment. In this perspective, the different ssNMR parameters characteristic for paramagnetic materials are discussed with a focus on their interpretation in terms of structure. This includes a summary of studies that have explored the information content of these ssNMR parameters, mostly to complement experimental data from other methods, e.g., X-ray diffraction. The presented overview aims to demonstrate how far ssNMR has hitherto been able to determine and refine the structures of materials and to discuss where it currently falls short of its full potential. We attempt to highlight how much further ssNMR can be pushed to determine and refine structure to deliver a comprehensive structural characterization of paramagnetic materials comparable to what is to date achieved by the combined effort of electron microscopy, diffraction, and spectroscopy.

We present a temperature-dependent intensity modulated two-photon excited fluorescence microscopy technique that enables high-resolution quantitative mapping of charge carrier dynamics in perovskite microcrystal film. By disentangling the emission into harmonics of the excitation modulation frequency, we analyze the first and second order charge carrier recombination processes, including potential accumulation effects. Our approach allows for a quantitative comparison of different emission channels at a micrometer resolution. To demonstrate the effectiveness of the method, we applied it to a methylammonium lead bromide perovskite microcrystal film. We investigated the temperature-dependent modulated imaging, encompassing the exciton dissociation-association and charge carrier trapping-detrapping equilibrium. Additionally, we explored the potential freezing out of traps and the phase transition occurring at low temperatures.

The antioxidant, anti-inflammatory, and muscle loss inhibitory effects of mealworm protein were investigated. Mealworm protein hydrolysate (MPH) was obtained by enzymatic hydrolysis and fractionated based on the molecular size. Although the protein content decreased with hydrolysis, it increased with an increase in size. Upon hydrolysis, essential and branched-chain amino acids decreased while free amino acids increased but decreased with an increase in size. The antioxidant activity increased upon hydrolysis and with an increase in molecular size. The anti-inflammatory effects were highest for MPH > 10 kDa and were similar to whey protein isolate (WPI), for IL-1β, IL-6, and TNF-α. Size fractionation did not significantly affect the anti-inflammatory effects. The MPH > 10 kDa (1.19-fold of control) resulted in the lowest myostatin expression in C2C12 muscle cells with and without LPS, which was similar to WPI (1.23-fold). Consequently, MPH may be a potential alternative to WPI.

Guava is a fruit that presents a high degree of perishability. This problem requires new effective technology with low environmental and human health impact for its resolution. A coating of tara gum with ZnO nanostructures is a promising alternative to increase the shelf life of this fruit. Therefore, the objective of this work was to optimize the production of the nanostructure, characterize it, and apply it in a guava coating. The nanostructure had a size of 173.15 nm and a polydispersity index of 0.601. Transmission electronic microscopy (TEM) confirmed a spherical morphology. ZnO nano showed antimicrobial activity against phytopathogenic fungi, being able to inhibit or slow down the growth of phytopathogens Colletotrichum gloeosporioides, Puccinia psidii, Diaporthe spp, and Penicillium spp. Nondestructive (visual and weight loss) and destructive (firmness, titratable acidity, pH, total solid residues, reducing sugars, and soluble sugars) tests were performed on guavas and showed very little change over 16 days post-harvest. The coating with ZnO nano resulted in better physical–chemical properties, and it verifies the potential use of the packaging produced for postharvest guava fruit conservation.

The isothermal bleaching of γ-irradiated glass was studied at elevated temperatures (280–340 °C) by real-time in situ optical microspectroscopy for the first time. The study was performed on γ-irradiated (0.83 and 1.99 MGy) International Simple Glass (ISG) borosilicate nuclear waste simulant made by Mo-SCI Corporation (Rolla, MO, USA). The current investigation proposes real-time optical transmission methodology for the activation energy assessment of isothermal bleaching of γ-irradiated glass. The method is based on robust quantification of the Urbach energy decay rates and yields similar activation energies for both doses within ∼0.24–0.26 eV.

Toward establishing the full design aspects of chitosan as a packaging material or as cling wraps, the chemical characteristics, thermal stability, optical transparency, Young’s modulus, elongation at fracture, and burst strength of pure and glycerol-added 100 μm-thick-chitosan films were investigated. Films of chitosan and films with 10%, 20%, and 30% w/w glycerol as the plasticizer were prepared per standard protocols. Electron microscopic analysis revealed that all films are homogeneous. The addition of glycerol did not alter the crystallinity, lowered the glass transition by ∼7 °C, decreased the thermal stability, decreased the roughness by 50%, and increased the optical transparency by 5%. It was found that the incorporation of glycerol decreased the Young’s modulus by two orders, increased the plastic strain at least by four times, and decreased the burst strength by at least two times. The results from this systematic analysis, including comparisons with existing packaging materials, provide a holistic picture for tailoring the properties of chitosan-based packaging materials for modified atmosphere packaging (MAP) toward sustainable development.

Our planet is facing food scarcity due to a rapidly growing population. Hence, food production and sources must adapt to accommodate a growing population and a changing climate in addition to being produced year-round in a small space with minimal growing inputs. Brassicaceae microgreens (BM) have a short growth cycle and can quickly grow with minimum inputs in a small area year-round, which make them an ideal candidate to diversify global nutrition and adapt to global climate change and urbanization. There is a growing interest in incorporating BM into daily diets as a source of phytochemicals and other nutrients. The phytochemicals in BM possess various biological activities, including antioxidant, anticancer, antidiabetic, and anti-inflammatory, which has piqued the interest of health-conscious consumers and researchers. Several growing conditions and postharvest practices have influenced the concentration of phytochemicals in BM. This review contains up-to-date information about the proximate compositions, phytochemicals contents, growing practices of BM, possible shelf life extending mechanisms, and their application in novel food product development and health benefits.

This study aims to investigate the effects of roasting dried coffee cherry on total phenol (TP), tannin, and flavonoid (TF) content and to examine the antioxidant and antimicrobial capacity of a coffee cherry husk-derived ethanol extract. Accordingly, the TP and TF content after different roasting regimens ranged from 9.00 to 123.49 mg GAE/g and 2.69 to 35.34 mg QE/g, respectively. The total tannin content decreased from 42.45 mg TAE/g to 0.27 mg TAE/g by the treatment. The DPPH radical and hydrogen peroxide scavenging capacities extended from 24.68 ± 0.05 to 93.83% and 14.45 to 76.07%, respectively, while the ferric reducing capacity increased from 10.85 to 47.02 mg AAE/g. An extract with increased TP and TF as well as stronger antioxidative activity was found to be produced by mild temperature (150 °C) roasting for 25 min or 180 °C for 10 to 15 min, after which the potency declines. The bacterial inhibition zones also increased from 7.03 to 21.30 mm and from 6.00 to 15.77 mm forE. coli and S. aureus, respectively. This study demonstrated that roasting degrades tannin and enhances the antioxidant and antibacterial properties of ethanol extracts of coffee husk.

Food safety is a basic necessity and has emerged as a global issue. The significant aspects of ensuring the food safety are sharing data, facts and figures, and standards to improve preventive control measures. The digitalization of data provides a vast amount of information regarding food safety that benefits public health. This review comprehensively covered categorizing existing food safety databases with the focus to provide data-driven knowledge of existing food safety-related sources/repositories, regulations/policy frameworks, and their potential uses concerning data access/analysis to drive informative consensus. These databases facilitate insights into hazard identification, enhancing decision-making, and develop risk evaluation-based strategies. More importantly, this information can help to improve the quality of the products and services in the global food supply chain in a timely manner. Therefore, it is critical to keep refining the databases so that updated information support handling safety issues for providing reliable and accurate data on food safety.