Effect of ultrasound combined with chemical pretreatment as an innovative non-thermal technology on the drying process, quality properties and texture of cherry subjected to radio frequency vacuum drying.

To obtain high-quality cherry products, ultrasound (US) combined with five chemical pretreatment techniques were used on cherry prior to radio frequency vacuum drying (RFV), including carboxymethyl cellulose coating (CMC), cellulase (CE), ethanol (EA), isomaltooligosaccharide (IMO), and potassium carbonate + ethyl oleate (PC + AEEO). The effect of different pretreatments (US-CMC, US-CE, US-EA, US-IMO, US-(PC + AEEO)) on the drying characteristics, quality properties, texture, and sensory evaluation of cherries was evaluated. Results showed that the dehydration time and energy consumption were decreased by 4.17 - 20.83 % and 3.22 - 19.34 %, respectively, and the contents of individual sugars, soluble solid, total phenolics (TPC), natural active substances, total flavonoids (TFC), and antioxidant properties (DPPH, ABTS and FRAP) were significantly increased after US combined with five chemical treatments (P < 0.05). Moreover, the pretreatment played important role in improving texture properties and surface color retention in the dried cherries. According to the sensory evaluation analysis, the dehydrated cherries pretreated with US-CMC exhibited the highest overall acceptance, texture, crispness, color, and sweet taste showed lower off-odor, bitter taste and sour taste compared to control and other pretreatments. The findings indicate that US-CMC pretreatment is a promising technique for increasing physicochemical qualities and dehydration rate of samples, which provides a novel strategy to processing of dried cherry.

Advances in valorization of sweet potato peels: A comprehensive review on the nutritional compositions, phytochemical profiles, nutraceutical properties, and potential industrial applications.

During food production, food processing, and supply chain, large amounts of food byproducts are generated and thrown away as waste, which to a great extent brings about adverse consequences on the environment and economic development. The sweet potato (Ipomoea batatas L.) is cultivated and consumed in many countries. Sweet potato peels (SPPs) are the main byproducts generated by the tuber processing. These residues contain abundant nutrition elements, bioactive compounds, and other high value-added substances; therefore, the reutilization of SPP holds significance in improving their overall added value. SPPs contain abundant phenolic compounds and carotenoids, which might contribute significantly to their nutraceutical properties, including antioxidant, antimicrobial, anticancer, prebiotic, anti-inflammatory, wound-healing, and lipid-lowering effects. It has been demonstrated that SPP could be promisingly revalorized into food industry, including: (1) applications in diverse food products; (2) applications in food packaging; and (3) applications in the recovery of pectin and cellulose nanocrystals. Furthermore, SPP could be used as promising feedstocks for the bioconversion of diverse value-added bioproducts through biological processing.

Assessing the efficacy of sanitizer sprays during brush or polyvinyl chloride (PVC) roller treatment to reduce Salmonella populations on whole mangoes.

Sanitizer spray and brush roller treatments have been documented as an effective means of reducing Salmonella on the surface of produce. The purpose of this study was to evaluate the efficacy of chlorine (NaOCl), peroxyacetic acid (PAA), and chlorine dioxide (ClO2) sprays to reduce Salmonella populations on the surface of mangoes during washing with brush or polyvinyl chloride (PVC) rollers. Whole mangoes were spot inoculated with 100 µL of a rifampicin-resistant Salmonella (8 log CFU/mL) cocktail at the equator and dried for 1 h. Mangoes were washed with a lab-scale roller system with either ground water (control), or sanitizers (100 ppm NaOCl, 80 ppm PAA, or 5 ppm ClO2) for 0, 5, 15, 30, or 60 s (n = 15 mangoes). Dey/Engley buffer (100 mL) was used to rinse mangoes before plating on media supplemented with rifampicin. NaOCl, PAA, and ClO2 spray (except for ClO2 at 30 s) had significantly higher reduction on Salmonella population than water spray at all treatment times (P ≤ 0.05) when brush rollers were used. All tested sanitizers also achieved a significantly higher reduction than water at 5 s when PVC rollers were used (P ≤ 0.05). Salmonella reductions achieved by brush and PVC rollers was not statistically different (P > 0.05). After a 5 s treatment on brush and PVC rollers, NaOCl, PAA, and ClO2 spray had ca. 3.03 and 3.45 log, 3.96 and 3.28 log, and 2.54 and 2.00 log CFU/mango reductions, respectively, whereas water spray achieved 1.75 and 0.98 log CFU/mango reduction. Addition of sanitizers to spray water used during brush or PVC washing in mango packinghouses can reduce Salmonella on mango surfaces.

Advances of protein-based emulsion gels as fat analogues: Systematic classification, formation mechanism, and food application.

Fat plays a pivotal role in the appearance, flavor, texture, and palatability of food. However, excessive fat consumption poses a significant risk for chronic ailments such as obesity, hypercholesterolemia, and cardiovascular disease. Therefore, the development of green, healthy, and stable protein-based emulsion gel as an alternative to traditional fats represents a novel approach to designing low-fat food. This paper reviews the emulsification behavior of proteins from different sources to gain a comprehensive understanding of their potential in the development of emulsion gels with fat-analog properties. It further investigates the emulsifying potential of protein combined with diverse substances. Then, the mechanisms of protein-stabilized emulsion gels with fat-analog properties are discussed, mainly involving single proteins, proteins-polysaccharides, as well as proteins-polyphenols. Moreover, the potential applications of protein emulsion gels as fat analogues in the food industry are also encompassed. By combining natural proteins with other components such as polysaccharides, polyphenols, or biopolymers, it is possible to enhance the stability of the emulsion gels and improve its fat-analog texture properties. In addition to their advantages in protecting oil oxidation, limiting hydrogenated oil intake, and delivering bioactive substances, protein-based emulsion gels have potential in food 3D printing and the development of specialty fats for plant-based meat.

Human milk fat substitutes rich in 1,3-dioleoyl-2-palmitoylglycerol and 1-oleoyl-2-palmitoyl-3-linoleoylglycerol simultaneously: Preparation strategy and simulated infant in vitro digestion.

In this study, fractionated palm stearin, oleic acid, and linoleic acid were selected as the base materials to prepare human milk fat substitutes (HMFS) rich in OPO and OPL by enzymatic acidolysis combined with physical blending. Under optimum conditions, contents of OPO, OPL, and sn-2 palmitic acid in the OPO and OPL-rich triacylglycerols (TAGs) were higher than that in commercial OPO-rich TAGs, with values of 37.25%, 28.12%, and 79.44%, respectively. Physical blending the OPO and OPL-rich TAGs (47%), bovine milk fat (18%), sunflower oil (13%), coconut oil (13%), corn oil (8%), and palm oil (1%) can obtain HMFS with a fat composition that like HMF. The fatty acid, sn-2 saturated fatty acid, and TAG contents of HMFS were within the lower and upper limit of HMF. The lipolysis degree of infant formula (IF) with HMFS as fat source is 9.0% higher than that of commercial plant oil-based infant formula (PIF), and 3.4% lower than that of human milk. IF with HMFS as fat source released less saturated free fatty acids and more saturated monoacylglycerols during digestion than that of PIF, which would help improve the IF fat utilization by infants.

Food contaminants: Impact of food processing, challenges and mitigation strategies for food security.

Food preparation involves the blending of various food ingredients to make more convenient processed food products. It is a long chain process, where each stage posing a risk of accumulating hazardous contaminants in these food systems. Protecting the public health from contaminated foods has become a demanding task in ensuring food safety. This review focused on the causes, types, and health risks of contaminants or hazardous chemicals during food processing. The impact of cooking such as frying, grilling, roasting, and baking, which may lead to the formation of hazardous by-products, including polycyclic aromatic hydrocarbons (PAHs), heterocyclic amines (HCAs), acrylamide, advanced glycation end products (AGEs), furan, acrolein, nitrosamines, 5-hydroxymethylfurfural (HMF) and trans-fatty acids (TFAs). Potential health risks such as carcinogenicity, genotoxicity, neurotoxicity, and cardiovascular effects are emerging as a major problem in the modern lifestyle era due to the increased uptakes of contaminants. Effects of curing, smoking, and fermentation of the meat products led to affect the sensory and nutritional characteristics of meat products. Selecting appropriate cooking methods include temperature, time and the consumption of the food are major key factors that should be considered to avoid the excess level intake of hazardous contaminants. Overall, this study underscores the importance of understanding the risks associated with food preparation methods, strategies for minimizing the formation of harmful compounds during food processing and highlights the need for healthy dietary choices to mitigate potential health hazards.

Changes in stresses sensitivity of ohmic heating-induced sublethally injured Staphylococcus aureus during repair: Potential mechanisms at the cellular and molecular levels.

Ohmic heating (OH), an emerging food processing technology employed in the food processing industry, raises potential food safety concerns due to the recovery of sublethally injured pathogens such as Staphylococcus aureus (S. aureus). In the present study, sensitivity to various stress conditions and the changes in cellular-related factors of OH-injured S. aureus during repair were investigated. The results indicated that liquid media differences (nutrient broth (NB), phosphate-buffered saline (PBS), milk, and cucumber juice) affected the recovery process of injured cells. Nutrient enrichment determines the bacterial repair rate, and the rates of repair for these media were milk > NB > cucumber juice > PBS. The sensitivity of injured cells to various stressors, including different acids, temperature, nisin, simulated gastric fluid, and bile salt, increased during the injury phase and subsequently diminished upon repair. Additionally, the intracellular ATP content, enzyme activities (Na+/K+-ATPase, Ca2+/Mg2+-ATPase, and T-ATPase) and ion concentrations (Mg2+, K+, and Ca2+) gradually increased during repair. After 5 h of repair, the intracellular substances content of cell's was significantly higher than that of the injured bacteria without repair, while some indicators (e.g., Na+/K+-ATPase, K+, and Ca2+) were not restored to the untreated level. The results of this study indicated that OH-injured S. aureus exhibited strengthened resistance post-recovery, potentially due to the restoration of cellular structures. These findings have implications for optimizing food storage conditions and advancing OH processes in the food industry.

Insights into chemical components, health-promoting effects, and processing impact of golden chanterelle mushroom Cantharellus cibarius.

Cantharellus cibarius (CC) is a culinary mushroom with significant commercial potential due to its diverse components and bioactive functions. CC is rich in carbohydrates, proteins, minerals, vitamins, and aroma compounds while being low in fat and calories. Moreover, CC contains an abundance of bioactive substances including phenolic compounds, vitamin precursors, and indole derivatives. Numerous studies have claimed that CC has diverse functions such as antioxidant, antimicrobial, immunoregulation, anti-inflammatory, antitumor, neuroprotective, antidiabetic, and prebiotic effects in in vivo or in vitro settings. In addition, a variety of thermal, physical, chemical, and biological treatment methods have been investigated for the processing and preservation of CC. Consequently, this study aims to present a comprehensive review of the chemical composition, health benefits, and processing techniques of CC. Furthermore, the issue of heavy metal accumulation in CC has been indicated and discussed. The study highlights the potential of CC as a functional food in the future while providing valuable insights for future research and identifying areas requiring further investigation.

Life cycle assessment for the land application of food processing wash-water and solid residuals.

A life cycle assessment (LCA) study was completed to understand the environmental impacts associated with the land application of wastes produced from rural food-processing operations for final disposal. The system boundaries for the two comprised scenarios included the storage of the produced non-agriculture source material (NASM), transportation to an applicable location, land application of the NASM, and the impacts of the final emissions to the soil and groundwater for a full year. The Tool for the Reduction and Assessment of Chemicals and Other Environmental Impacts (TRACI) v2.1 was selected as the impact assessment method. Furthermore, SimaPro 8.0.4.26 was the LCA model version that was used with all the databases included. Overall, the LCA study showed that the most significant environmental impacts associated with the disposal process resulted from carcinogenic and eutrophication emissions. The component that contributed the most to carcinogenic impacts was found to be from the material required to create the concrete storage tank. Additionally, eutrophication was identified to be a potential significant impact, if proper setback requirements are not followed for the NASM material. Results of the study look to inform stakeholders about the benefits and risks encountered from NASM disposal. PRACTITIONER POINTS: Life cycle assessment was completed on a representative NASM disposal system using land application. Concrete tank used for storage of NASM had the most significant impact in carcinogenic emissions. Eutrophication impacts were the second most significant impact behind carcinogenic emissions.

Comparison of chemical compositions and aroma characteristics of walnut oil prepared by different roasting processes.

Walnut oil is an edible oil with high nutritional value, and the roasting process influences its quality and flavor. This study aimed to investigate the effects of roasting on the fatty acid composition, bioactive compounds (tocopherols, polyphenols, and phytosterols), and antioxidant capacity of walnut oil. Additionally, the aroma compounds and sensory characteristics were evaluated to comprehensively assess the variations in walnut oil after roasting. Roasting resulted in no notable impact on the fatty acid composition of walnut oil but increased the content of tocopherols and polyphenols in walnut oil, increasing its antioxidant capacity. Heavy roasting (160°C/20 min) reduced the phytosterol content in walnut oil by 2.3%. In total, 146 volatile compounds were detected in both cold-pressed and roasted walnut oil using headspace solid-phase microextraction-gas chromatography-mass spectrometry, and 32 key aroma compounds were identified. Aromatic aldehydes, aliphatic aldehydes, and heterocyclic compounds significantly contributed to fragrant walnut oil. Furthermore, the principal component analysis based on quality characteristics and sensory evaluation indicated that moderate roasting (130°C/20 min, 130°C/30 min, and 160°C/10 min) provided walnut oil with a sweet, nutty, and roasted aroma, as well as high levels of linoleic acid, phytosterols, and γ-tocopherol. Although heavy roasting (160°C/15 min and 160°C/20 min) enhanced the antioxidant capacities of walnut oils due to high levels of polyphenols, the oils exhibited an unpleasant burnt aroma. This study showed that roasting promoted the quality and flavor of walnut oil, and moderate conditions endowed walnut oil with a characteristic-rich flavor while maintaining excellent quality.

Pectin forms polymeric pigments by complexing anthocyanins during red winemaking and ageing.

The long-term stability of red wine color depends on the formation of polymeric pigments from anthocyanins. Although there is still a lot of uncertainty about the specific structure of this diverse group of pigments, there is consensus that they are reaction products of anthocyanins and other polyphenols. Interactions between anthocyanins and pectic polysaccharides have been suggested to stabilize anthocyanins. This study explores the impact of such interactions by adding pectin during red winemaking. The results demonstrate that these interactions induce the formation of additional polymeric pigments which enhance the pigment stability during fermentation and aging. While initial pigment formation is higher in wines with added pectin, a notable proportion of the complexes degrades in the later stages of fermentation. Presumably, tannins form insoluble complexes with pectin, reducing tannin concentration by more than 300 mg/L. Anthocyanin concentrations decrease by over 400 mg/L, and polymeric pigments double. Anthocyanins that form polymeric pigments with pectic polysaccharides expand the range of pigments in red wines with possible consequences for the sensory properties of the wine. These findings highlight the complex interactions between pectin, anthocyanins, and tannins, and their influence on pigment formation and wine composition during fermentation and aging.

Effect of thermal pretreatment and gastrointestinal digestion on the bioactivity of dry-cured ham bone enzymatic hydrolyzates.

This study reports the effect of thermal pretreatment and the use of different commercial proteolytic enzymes (Protamex, Flavourzyme, Protana prime, and Alcalase) on the free amino acid content (FAA), peptide profile, and antioxidant, antidiabetic, antihypertensive, and anti-inflammatory potential (DPPH, FRAP, and ABTS assay, DPP-IV, ACE-I, and NEP inhibitory activities) of dry-cured ham bone hydrolyzates. The effect of in vitro digestion was also determined. Thermal pretreatment significantly increased the degree of hydrolysis, the FAA, and the DPP-IV and ACE-I inhibitory activities. The type of peptidase used was the most significant factor influencing antioxidant activity and neprilysin inhibitory activity. Protana prime hydrolyzates failed to inhibit DPP-IV and neprilysin enzymes and had low values of ACE-I inhibitory activity. After in vitro digestion, bioactivities kept constant in most cases or even increased in ACE-I inhibitory activity. Therefore, hydrolyzates from dry-cured ham bones could serve as a potential source of functional food ingredients for health benefits.

Condensed tannins-Their content in plant foods, changes during processing, antioxidant and biological activities.

Condensed tannins are considered nutritionally undesirable, because they precipitate proteins, inhibit digestive enzymes, and can affect the absorption of vitamins and minerals. From the consumer's point of view, they impart astringency to foods. Yet, they are viewed as a double-edged sword, since they possess antioxidant and anti-inflammatory activities. Intake of a small quantity of the right kind of tannins may in fact be beneficial to human health. This chapter reports on the chemical structure of condensed tannins, their content in plants and food of plant origin, how they are extracted, and methods for their determination. A description of the effects of processing on condensed tannins is discussed and includes soaking, dehulling, thermal processing (i.e., cooking, boiling, autoclaving, extrusion), and germination. The astringency of condensed tannins is described in relation to their interactions with proteins. Finally, details about the biological properties of condensed tannins, including their antimicrobial, anti-inflammatory, anticancer, anti-diabetic, and anti-obesity activities, are reviewed.

Sea cucumber significance: Drying techniques and India's comprehensive status.

Sea cucumbers, members of the echinoderm class Holothuroidea, are marine invertebrates with ecological significance and substantial commercial value. With approximately 1700 species, these organisms contribute to marine ecosystems through nutrient cycling and face various threats, including overfishing and habitat loss. Despite their importance, they are extensively exploited for diverse applications, from seafood to pharmaceuticals. This study investigates sea cucumbers' nutritional profile and bioactive elements, emphasizing their role as sources of essential compounds with potential health benefits. The demand for sea cucumbers, especially in dried form, is significant, prompting exploration into various drying techniques. Examining the global trade in sea cucumbers highlights their economic importance and the conservation challenges they face. Conservation efforts, such as awareness campaigns and international collaboration, are evaluated as essential steps in combating illicit trade and promoting the sustainable stewardship of sea cucumber populations. PRACTICAL APPLICATION: Around 1700 species of sea cucumbers were identified as vital ecological scavengers in the Holothuroidea class. High commercial value due to their health benefits, particularly their demonstrated inhibitory effect against various types of cancer. "Beche-de-mer" holds a 90% market share and is regarded as a luxury food item in Southeast Asian countries. Due to overexploitation, the species is classified as Schedule I under the Wildlife Protection Act (WPA) in India, prompting the implementation of a blanket ban on their harvesting to ensure its conservation.

Impact of pre- and post-fermentation fining with polyvinylpolypyrrolidone on the chemical stability and aromatic profile of Viognier wine.

Polyvinylpolypyrrolidone (PVPP) is a synthetic, insoluble polymer that can be added to white wines to improve the chemical stability of the final product by precipitating unstable low molecular weight phenolic compounds responsible for visual defects and undesirable flavor characteristics (e.g., excessive bitterness and/or astringency). The objective of this study was to characterize the effects of PVPP on the quality characteristics of Viognier wine when added pre- or post-fermentation as compared to an untreated control wine. Both PVPP-treated wines contained significantly lower concentrations of monomeric phenolics and browning pigments than the control wine (p ≤ 0.05). The addition of PVPP prior to fermentation conferred protection against oxidation of the wine as measured by acetaldehyde concentration (p ≤ 0.05). Analysis of the volatile aroma profile of each wine by headspace solid phase microextraction gas chromatographymass spectrometry (HS-SPME-GC-MS) revealed that the overarching aroma profiles of the PVPP-treated wines were significantly different from the control wine, but there was no difference between wines treated with PVPP pre-fermentation versus those treated post-fermentation. Specifically, statistically significant differences were observed in 9 of the 22 quantified aroma compounds, including those notably associated with the "stone fruit" aroma of Viognier. A negative correlation was identified between aroma compound concentration removal and the hydrophobicity of each compound, suggesting that the observed differences in aroma may be due to adsorption of aroma compounds by PVPP. The findings from this study present risks and benefits to wine quality upon treatment with PVPP at commercially recommended levels, and provide potentially valuable information for industrial wine producers.

Catalytic infrared radiation dry-peeling Technology for non-Frozen and Frozen Grapes: Effects on temperature, peeling performance, and quality attributes.

This study introduces catalytic infrared radiation (CIR) heating technology as an eco-friendly alternative to conventional grape lye peeling (LP). The effects of heating time and distance on non-frozen and frozen grapes were assessed for temperature, peeling performance, and quality attributes. The findings indicate that CIR heating achieves complete dry-peeling of grapes. Extended heating times and reduced distances improve peeling performance, with more favorable results observed in frozen grapes compared to non-frozen ones. Grapes peeled using CIR demonstrated enhanced hardness, color, sugar-acid ratio, bioactive compounds, and antioxidant capacity, compared to those peeled using LP. Importantly, the frozen samples preserved their quality after CIR dry-peeling treatment. Based on peeling performance and quality attributes, the optimum heating times are established at 160 s for non-frozen grapes and 50 s for frozen grapes, at a heating distance of 5 cm. Therefore, CIR dry-peeling is recommended as an eco-friendly and quality-enhancing sustainable grape processing technology.

Optimization of thermosonication conditions for critical quality parameters of watermelon juice using response surface methodology.

Topical consumer interest in natural, healthier, safer and nutritional juice, has inspired the search for innovative technologies that can minimize product degradation. In this regard, thermosonication has been proposed as a potential processing technology that can preserve and produce "fresh" products. Watermelon (Citrullus lanatus) juice is a nutrient-rich fruit juice that is desired by consumers due to its appealing color, pleasant odor, sweet taste and low-calorie content. This fruit juice is, however, highly perishable and prone to microorganisms, because of its neutral pH value and high amount of water activity. In addition, it is thermo-sensitive and therefore degrades quickly under thermal processing. This study aimed to identify the optimal thermosonication processing conditions for retaining the critical quality parameters (lycopene, ß-carotene, ascorbic acid and total polyphenolic content) of watermelon juice. Response surface methodology, employing a central composite design, was used to determine the effects of temperature (18-52 °C), processing time (2-13 min) and amplitude level (24-73 µm) at a constant frequency of 25 kHz. The highest quality parameters were obtained at 25 °C, 2 min, and 24 µm at a constant frequency of 25 kHz, which resulted in lycopene of 8.10 mg/100 g, ß-carotene of 0.19 mg/100 g, ascorbic acid of 3.11 mg/100 g and total polyphenolic content of 23.96 mg/GAE/g with a desirability of 0.81. The proposed model was adequate (p < 0.0001), with a satisfactory determination coefficient (R2) of less than 0.8 for all phytochemicals. Thermosonicated watermelon juice samples showed minimal changes in their phytochemical properties, when compared to fresh juices; the lycopene content showed a significant increase after thermosonication, and a significant retention of ß-carotene, ascorbic acid and total polyphenolic acid was observed. According to the findings, thermosonication could be a viable method for preserving watermelon juice, with minimal quality loss and improved functional attributes.

Chemical and physical changes induced by cold plasma treatment of foods: A critical review.

Cold plasma treatment is an innovative technology in the food processing and preservation sectors. It is primarily employed to deactivate microorganisms and enzymes without heat and chemical additives; hence, it is often termed a "clean and green" technology. However, food quality and safety challenges may arise during cold plasma processing due to potential chemical interactions between the plasma reactive species and food components. This review aims to consolidate and discuss data on the impact of cold plasma on the chemical constituents and physical and functional properties of major food products, including dairy, meat, nuts, fruits, vegetables, and grains. We emphasize how cold plasma induces chemical modification of key food components, such as water, proteins, lipids, carbohydrates, vitamins, polyphenols, and volatile organic compounds. Additionally, we discuss changes in color, pH, and organoleptic properties induced by cold plasma treatment and their correlation with chemical modification. Current studies demonstrate that reactive oxygen and nitrogen species in cold plasma oxidize proteins, lipids, and bioactive compounds upon direct contact with the food matrix. Reductions in nutrients and bioactive compounds, including polyunsaturated fatty acids, sugars, polyphenols, and vitamins, have been observed in dairy products, vegetables, fruits, and beverages following cold plasma treatment. Furthermore, structural alterations and the generation of volatile and non-volatile oxidation products were observed, impacting the color, flavor, and texture of food products. However, the effects on dry foods, such as seeds and nuts, are comparatively less pronounced. Overall, this review highlights the drawbacks, challenges, and opportunities associated with cold plasma treatment in food processing.

Metabolomics comparison of four varieties apple with different browning characters in response to pretreatment during pulp processing.

Browning commonly appeared in apple processing, which varied in different apple varieties. Present work investigated the metabolomics of four varieties apple of Yataka, Gala, Sansa, and Fuji, which possessed different browning characteristics and related enzymes. Sansa as browning insensitive apple variety, exhibited the least chroma change with the lowest PPO activity and the highest SOD activity among the four apple varieties. Browning inhibition pretreatment increased the activity of SOD and PAL and decreased PPO and POD activity. In addition, metabolomic variances among the four apple varieties (FC), their browning pulp (BR) and browning inhibition pulp (CM) were compared. And the key metabolites were in-depth analyzed to match the relevant KEGG pathways and speculated metabolic networks. There were 487, 644, and 494 significant differential metabolites detected in FC, BR and CM, which were consisted of lipids, benzenoids, phenylpropanoids, organheterocyclic compounds, organic acids, nucleosides, accounting for 23 %, 11 %, 15 %, 16 %, 11 % of the total metabolites. The differential metabolites were matched with 39, 49, and 36 KEGG pathways in FC, BR, and CM, respectively, in which other secondary metabolites biosynthesis metabolism was the most significant in FC, lipid metabolism was the most significant in BR and CM, and energy metabolism was markedly annotated in CM. Notably, Sansa displayed the highest number of differential metabolites in both its BR (484) and CM (342). The BR of Sansa was characterized by flavonoid biosynthesis, while the other three apple varieties were associated with α-linolenic acid metabolism. Furthermore, in browning sensitive apple varieties, the flavonoid and phenylpropanoid biosynthesis pathway was significantly activated by browning inhibition pretreatment. Phenolic compounds, lipids, sugars, organic acids, nucleotides, and adenosine were regulated differently in the four apple varieties, potentially serving as key regulatory sites. Overall, this work provides novel insight for browning prevention in different apple varieties.

Effect of radio frequency roasting on the lipid profile of peanut oil and the mechanism of lipids transformation: Revealed by untargeted lipidomics approach.

Radio frequency (RF) heating has been proved an alternative roasting method for peanuts, which could effectively degrade aflatoxins and possesses the advantages of greater heating efficiency and penetration depth. This study aimed to investigate the influences of RF roasting on the lipid profile of peanut oil under 150 °C target temperature with varied peanut moisture contents (8.29 % and 20 %) and holding times (0, 7.5, and 15 min), using ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-QTOF-MS/MS)-based lipidomics. In total, 2587 lipid species from 35 subclasses were identified. After roasting, the contents of sterol lipid (ST) and subclasses of glycerophospholipids (GPs) and glycoglycerolipids increased significantly, while fatty acid (FA), Oxidized (Ox-) FA, cholesterol (CE), and all subclasses of glycerolipids (GLs) decreased, and 1084 differential lipids were screened. The highest ST and lowest CE contents in peanut oil were achieved by medium roasting (7.5 min). The raise in moisture content of peanut simply affected a few GPs subclasses adversely. Compared with hot air (HA) roasting, RF decelerated lipid oxidation, showing higher levels of diacylglycerol, triacylglycerol and FA, with no additional negative impact and only 69 exclusive differential lipids. During RF roasting, hydrolysis and oxidation of fatty acyl chains into secondary oxides were the central behaviors of lipids transformation. This study could provide insights into the lipid changes and transformation mechanism of peanut oil by RF roasting processing.