Impact of minimal processing on orange bioactive compounds during refrigerated storage

Tea Polyphenols Inhibit the Occurrence of Enzymatic Browning in Fresh-Cut Potatoes by Regulating Phenylpropanoid and ROS Metabolism

During fresh-cut processing, potatoes lose their inherent protective cellular structure, leading to enzymatic browning that compromises sensory and edible quality. Tea polyphenols (TPs), natural preservatives with potent reducing properties, are hypothesized to impact this browning process. However, their influence and regulatory mechanism on the enzymatic browning of fresh-cut potatoes remain poorly understood. This study used the "Holland Seven" potato as the research material to explore the effects of a treatment with different TP concentrations (0.1 g L-1, 0.2 g L-1, and 0.3 g L-1) on the browning phenomenon and quality of fresh-cut potatoes during storage. The results showed that appropriate concentrations of TP treatment had a good preservation effect on the appearance and edible quality of fresh-cut potatoes. Furthermore, exogenous TP treatment reduced the content of enzymatic browning substrates (caffeic acid, p-coumaric acid, and ferulic acid) by regulating phenylpropanoid metabolism. Meanwhile, TP treatment augmented the activities of antioxidative enzymes (superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase), maintained higher levels of ascorbic acid (Vc), and reduced glutathione (GSH). Consequently, the TP treatment could inhibit enzymatic browning by regulating reactive oxygen species (ROS) metabolism and the Vc-GSH cycle in fresh-cut potatoes.

Use of Ultrasonic Cleaning Technology in the Whole Process of Fruit and Vegetable Processing

In an era of rapid technological development, ultrasound technology is being used in a wide range of industries. The use of ultrasound technology in fruit and vegetable processing to improve production efficiency and product quality has been an important research topic. The cleaning of whole fresh fruits and vegetables is an important part of fruit and vegetable processing. This paper discusses the development process of components of the ultrasonic equipment, the application of ultrasonic technology in fruit and vegetable cleaning, and the research advances in ultrasonic cleaning technology. Moreover, the feasibility of ultrasonication of fruits and vegetables for cleaning from the perspectives of microbial inactivation, commodity storage, and sensory analysis were discussed. Finally, the paper identified the inevitable disadvantages of cavitation noise, erosion, and tissue damage in fruit and vegetable processing and points out the future directions of ultrasonic fruit and vegetable cleaning technology.

Understanding Blood versus Blond Orange Consumption: A Cross-Cultural Study in Four Countries

Understanding consumer perceptions and attitudes to specific fruit is key information for not only increasing fruit consumption, but also for marketing reasons. It may also give clues to breeders to set quality objectives. This study explores different aspects that help to explain blood vs. blond orange consumption: availability and consumption habit, satisfaction attributes, facilitators and consumption barriers, consumption contexts, expectations and purchase intention. The study was conducted in China, Mexico, Spain and Italy, where citrus fruit consumers were invited to respond an online questionnaire. Our results revealed Italy as the country with the highest availability and consumption of blood oranges, followed by China, Mexico and Spain. "Liking" and "healthy properties" were the most important reasons for consumption irrespectively of orange type, but certain differences among countries were detected in secondary reasons. In all the countries, "juicy" was the most relevant attribute for consumer satisfaction, followed by flavour/taste attributes. "Aromatic" and "unfibrous" were substantial requirements for Italians and Chinese, while Spaniards attached importance to the blood oranges colour. Regarding consumption contexts, "eat with salt or chilly powder" was specific for Mexico, while "to improve health", "as a gift" or "at a restaurant" were contexts mainly cited in China. Despite taste preferences for other fruit being the main consumption barrier in all the countries for both orange types, the relevance of other barriers depended on culture and orange type. Mexican participants seemed to take a more neophobic attitude to blood oranges, while "inconvenient" was reported as a barrier for consuming blond ones in Spain and China. We conclude that blond and blood oranges can co-exist on markets at a high consumption rate, as in Italy. Specific interventions are needed in other countries because consumer attitudes to oranges, mainly blood ones, depend on culture.

Influence of the formula on the properties of a fast dispersible fruit tablet made from mango, Chlorella, and cactus powder

Tableting of fruit powders is gaining popularity because of the advantages it brings in, such as ease of storage, transportation, and use, and effervescent tablets could be a good alternative to accomplish fast dissolving. The present study provides a specific effervescent tablet formulation that is appropriate for the delivery of mango, cactus, and Chlorella fruit powder. The direct compression method was employed. A series of disintegration time, tensile strength, and moisture content tests were performed on the different formulations at each stage. The effects of effervescent agents' ratio, fruit powder proportion, acid and alkali content, and mannitol and lactose content on tablet properties were investigated. The results indicated that the tablet properties were highly influenced by formulation, especially the ratios of effervescent agents, fruit powders, acid to alkali ratio, as well as mannitol to lactose ratio. The best performing formulation was as follows, 45% effervescent agents (citric acid monohydrate:sodium bicarbonate = 1.3:1), 35% adhesives (mannitol:lactose = 1:8), and 20% mixed fruit powders (mango:cactus:Chlorella fruit powders = 14:5:1). With this formula, the moisture content was 3.62% and the disintegration time was 154 s, as well as a sufficient tensile strength of 2.32 MPa. Our study presented useful findings regarding the specific effects of changing ingredient ratios on tablet strength and other properties and provided a basis for the potential of using mango, cactus and microalgae powders as novel functional ingredients for fruit powder effervescent tablets. This may be used as a basis for further research on tableting.

Targeting hallmarks of cancer with a food-system-based approach

Although extensive resources are dedicated to the development and study of cancer drugs, the cancer burden is expected to rise by about 70% over the next 2 decade. This highlights a critical need to develop effective, evidence-based strategies for countering the global rise in cancer incidence. Except in high-risk populations, cancer drugs are not generally suitable for use in cancer prevention owing to potential side effects and substantial monetary costs (Sporn, 2011). There is overwhelming epidemiological and experimental evidence that the dietary bioactive compounds found in whole plant-based foods have significant anticancer and chemopreventative properties. These bioactive compounds often exert pleiotropic effects and act synergistically to simultaneously target multiple pathways of cancer. Common bioactive compounds in fruits and vegetables include carotenoids, glucosinolates, and polyphenols. These compounds have been shown to target multiple hallmarks of cancer in vitro and in vivo and potentially to address the diversity and heterogeneity of certain cancers. Although many studies have been conducted over the past 30 y, the scientific community has still not reached a consensus on exactly how the benefit of bioactive compounds in fruits and vegetables can be best harnessed to help reduce the risk for cancer. Different stages of the food processing system, from "farm-to-fork," can affect the retention of bioactive compounds and thus the chemopreventative properties of whole foods, and there are opportunities to improve handling of foods throughout the stages in order to best retain their chemopreventative properties. Potential target stages include, but are not limited to, pre- and postharvest management, storage, processing, and consumer practices. Therefore, there is a need for a comprehensive food-system-based approach that not only taking into account the effects of the food system on anticancer activity of whole foods, but also exploring solutions for consumers, policymakers, processors, and producers. Improved knowledge about this area of the food system can help us adjust farm-to-fork operations in order to consistently and predictably deliver desired bioactive compounds, thus better utilizing them as invaluable chemopreventative tools in the fight to reduce the growing burden of cancer worldwide.

Transcriptome analysis of acerola fruit ripening: insights into ascorbate, ethylene, respiration, and softening metabolisms

The first transcriptome coupled to metabolite analyses reveals major trends during acerola fruit ripening and shed lights on ascorbate, ethylene signalling, cellular respiration, sugar accumulation, and softening key regulatory genes. Acerola is a fast growing and ripening fruit that exhibits high amounts of ascorbate. During ripening, the fruit experience high respiratory rates leading to ascorbate depletion and a quickly fragile and perishable state. Despite its growing economic importance, understanding of its developmental metabolism remains obscure due to the absence of genomic and transcriptomic data. We performed an acerola transcriptome sequencing that generated over 600 million reads, 40,830 contigs, and provided the annotation of 25,298 unique transcripts. Overall, this study revealed the main metabolic changes that occur in the acerola ripening. This transcriptional profile linked to metabolite measurements, allowed us to focus on ascorbate, ethylene, respiration, sugar, and firmness, the major metabolism indicators for acerola quality. Our results suggest a cooperative role of several genes involved in AsA biosynthesis (PMM, GMP1 and 3, GME1 and 2, GGP1 and 2), translocation (NAT3, 4, 6 and 6-like) and recycling (MDHAR2 and DHAR1) pathways for AsA accumulation in unripe fruits. Moreover, the association of metabolites with transcript profiles provided a comprehensive understanding of ethylene signalling, respiration, sugar accumulation and softening of acerola, shedding light on promising key regulatory genes. Overall, this study provides a foundation for further examination of the functional significance of these genes to improve fruit quality traits.

Effect of Gelatin-Based Edible Coatings Incorporated with Aloe vera and Black and Green Tea Extracts on the Shelf Life of Fresh-Cut Oranges

The aim of this study was to evaluate the effect of gelatin coating incorporated with Aloe vera gel (50,100%) and green and black tea extracts (5,10%) on physicochemical, microbial, and sensorial properties of fresh-cut oranges at 4°C for 17 days. Significant differences in terms of quality parameters were observed between the control and coated fresh-cut oranges. The highest variation of quality parameters was observed in control, while the least variations were observed in coated slices with 100% Aloe vera and 10% green tea extract. The weight loss was increased with time, but the coating treatment especially with 100% Aloe vera had significant effect on the prevention of weight loss. Also, Aloe vera coated samples obtained the highest score in sensory evaluation. Coating with gelatin incorporated with Aloe vera and green tea extracts successfully retarded the microbial growth and therefore extended the shelf life of fresh-cut oranges during cold storage.

Fast simultaneous determination of prominent polyphenols in vegetables and fruits by reversed phase liquid chromatography using a fused-core column

A reversed-phase high-performance liquid chromatography method with photodiode array detection has been developed enabling the joint determination of 17 prominent flavonoids and phenolic acids in vegetables and fruits. A multi-segmented gradient program using a fused-core column for the separation of several phenolic classes (phenolic acids and flavonoids) has been optimised. The influence of extraction conditions (sample freeze-drying, ultrasound extraction, solvent composition and extraction time) has been also optimised using response surface methodology with tomato samples as a model. Complete recoveries (76-108%) were obtained for the phenolic compounds present in tomato. The developed method provided satisfactory repeatability in terms of peak area (RSD<2.9%) and retention time (RSD<0.2%) both for standards and real samples. Detection limits ranged between 3 and 44μgkg(-1) for the detected polyphenols. This method is recommended for routine analysis of large number of samples typical of production quality systems or plant breeding programs.

Do sun- versus shade-grown kiwifruits perform differently upon storage? An overview of fruit maturity and nutraceutical properties of whole and fresh-cut produce

Fresh-cut produce represents a good method to save about 25% of the kiwifruit not useful to meet the fresh fruit-marketing standard due to improper size and shape. For that reason, fresh-cut kiwifruit has been extensively studied. However, the comprehension of the influence of some aspects of cultivation might further increase the shelf life as well as the nutritional values of that fruit. This study explored the hypothesis that kiwifruits grown fully exposed to sunlight or partially shaded differently perform upon storage as whole fruit and as minimally processed produce. Flesh firmness (FF), total solids soluble (SSC), ascorbate (AAT), flavonoids (TFO), and phenols (TF) contents were evaluated in sliced and whole fruit upon 3 days of storage at 4 °C after 75 days of cold chamber storage at 0 °C. The activities of two enzymes related to the softening process, polygalacturonase (PG) and pectinmethylesterase (PME), were evaluated as well. FF and SSC were constitutively higher in sun-exposed fruit, and those characteristics remained higher during the storage as whole fruit. Greater constitutive content of AAT, TFO, and TP was found in sun-exposed whole fruit, although after cutting the reduction in their content was significantly lower in shaded fruits. PME and PG activities were higher only in whole shaded fruits, whereas no relevant differences occurred after cutting. In summary, sun-exposed fruits were more suitable for the fresh-fruit market, whereas the shaded counterpart displayed a good predisposition for use as fresh-cut produce, maintaining similar fruit maturity properties but higher nutraceutical values when sliced than fruit grown under full sun.

Influence of hot water dip on fruit quality, phenolic compounds and antioxidant capacity of Satsuma mandarin during storage

The influence of hot water dips (50, 52 and 54 ℃ for 3 min) on fruit quality, phenolic compounds and antioxidant capacity of Satsuma mandarin during 60 days’ storage at 10 ℃ was investigated. Hot water dips did not affect fruit quality attributes as well as ascorbic acid content, and 50 ℃ treatment significantly reduced fruit weight loss. Significant increases of flavonoids were found in all hot water treated fruit from after treatments till 15 days of storage, whereas phenolic acids were not greatly affected. Hot water dipping at 50 ℃ significantly increased total phenolics and antioxidant capacity of Satsuma mandarin immediately after treatment and maintained similar levels with control during storage, while 52 and 54 ℃ treatments showed relatively lower levels. The results suggested that hot water dipping at 50 ℃ for 3 min can be a promising way to retain functional quality of storing Satsuma mandarin.

Influence of technological processes on phenolic compounds, organic acids, furanic derivatives, and antioxidant activity of whole-lemon powder

The healthy properties of citrus fruits have been attributed to ascorbic acid and phenolic compounds, mainly to flavonoids. Flavonoids are important phytonutrients because they have a wide range of biological effects that provide health-related properties. In this context, this study seeks to characterise the phenolic compounds in lemon and their stability in different drying processes (freeze-drying and vacuum-drying) and storage conditions (-18 and 50°C for 1 and 3months). A powerful high-performance liquid chromatography coupled to DAD and electrospray-ionization time-of-flight mass spectrometry (HPLC-ESI-TOF-MS) method has been applied for the separation, identification, and quantification of 19 phenolic compounds and 4 organic acids. To our knowledge, two hydroxycinnamic acids have been identified for the first time in lemon. Folin-Ciocalteu was applied to determine total phenolic compounds and TEAC, FRAP, and ORAC were applied to determine the antioxidant capacity of lemon. Total phenolic content significantly differed in the samples analysed, vacuum-dried lemon showing the highest phenolic content, followed by freeze-dried lemon and, finally, vacuum-dried lemon stored at 50°C for 1 and 3months. The content in furanic compounds was determined to evaluate the heat damage in lemon and it was showed an increase with the thermal treatment because of the triggering of Maillard reaction. As exception of ORAC, antioxidant-capacity assays were not correlated to phenolic content by HPLC due to the formation of antioxidant compounds during Maillard reaction.

Physicochemical and microbiological characteristics of minimally processed 'Champagne' oranges (Citrus reticulata × Citrus sinensis) in different packgings

The objective of this study was to investigate the influence of the level of minimal processing and modified atmosphere on the quality of 'Champagne' orange stored under refrigeration. The fruits were subjected to the following processing: a) whole fruit without flavedo; b) whole fruit without flavedo and albedo; and c) segmented into wedges and packed as follows: uncoated packaging (control); polyethylene film; PVC film; gelatin-based edible films (3%); and polyesthyrene translucent plastic container with a lid. The minimally processed oranges were stored at 5 ± 1°C for 8 days and were subjected to physicochemical and microbiological analyses every two days. Greater weight loss occurred in fruits without flavedo and segmented, uncoated, and coated with the edible gelatin film During storage, there was a slight increase in Total Soluble Solids (TSS) for the treatments with greater weight loss and reduction in acidity and ascorbic acid, regardless of the packaging type. The microbial counts did not exceed the acceptable limits in the treatments; however, higher counts were observed at the end of storage. The minimally processed fruit packed in lidded polystyrene containers and polyethylene and PVC films kept their overall fresh visual appearance with a few physicochemical and microbiological changes up to the 8th day of storage.

Changes in the structure and antioxidant properties of onions by high pressure treatment

Onions have antioxidant properties and they are an important source of bioactive compounds such as phenols. The aim of this work was to study the effect of high hydrostatic pressure (HHP) (100-600 MPa/1-3 min/25 °C) on the microstructure and antioxidant properties of onions (cv. Doux) and its relationship with changes in the extractability of potential health-related compounds. Cryo scanning electron microscopy was used to study the microstructure. Vitamin C, total phenolic content and antioxidant activity (DPPH˙, ABTS˙(+), FRAP) were also analyzed. Tonoplast, plasmalemma and cell walls were affected by the HHP treatment and it favored the diffusion of the cellular content to the intercellular spaces. Vitamin C did not show significant changes, whereas the extracted phenolic content and antioxidant activity increased at pressures of 300 or 600 MPa. Therefore, it could be concluded that HHP produced changes in membrane permeability and disruption of cell walls favoring the release of phenolic compounds from tissue and, in consequence, improving their extractability.

Short cold storage enhances the anthocyanin contents and level of transcripts related to their biosynthesis in blood oranges

The health benefits associated with the consumption of anthocyanin-containing foods are extensively documented. Mature fruits of blood oranges and their hybrids are characterized by the presence of these bioactive pigments, the abundance of which can be enhanced by storing fruit at cooling nonfreezing temperature. In this work the effects of short low-temperature exposure (4 °C × 15 days) upon orange anthocyanin content and the expression of structural genes belonging to the pigment biosynthesis pathway were investigated. The results highlight that anthocyanin levels of fruit exposed to cold sharply increase, reaching, after 6 days of storage, a value 8 times higher than that observed in the time zero samples, thus suggesting that fruit with enhanced health-related attributes might be obtained at this storage stage. The analysis of gene expression shows that the amount of transcripts of all considered genes (CM1, PAL, CHS, DFR, ANS, UFGT, and GST) sharply increased after 3-6 days of cold storage, confirming previous data showing that the biosynthesis of anthocyanins is a cold-regulated pathway. By comparing the expression of selected genes (PAL, DFR, and UFGT) between blood and common oranges, it turns out that those genes strictly involved in anthocyanin biosynthesis are not cold responsive in common oranges. Moreover, the data highlight that the EST encoding the transcription factor NAC domain protein is selectively induced by cold in blood oranges but not in common oranges, thus proposing it as a candidate gene specifically involved in blood orange response to cold exposure.