Fresh Food Research Articles

COMPETITIVENESS OF SOUTH AFRICAN ORANGES IN ASIAN STRATEGIC MARKETS: THE CASE OF MAIN COMPETITORS

This study employed various descriptive, conceptual, and empirical models to measure South Africa’s competitiveness in the Asian strategic markets concerning its competitors from 2003 to 2022. The competitiveness measurements included relative comparative advantage, the net export index, relative trade advantage, and constant market share analysis. The data were sourced from official databases such as the World Bank, FAO, ITC, export potential map, and World Integrated Trade Solutions (WITS). The South African competitiveness of oranges in the specified strategic markets realized a positive competitive effect of 2.46%, indicating a gain in the market due to increased competitiveness of the fresh food sector in the world market. The RCA values were above 1, with most of the values closer to 20 indicating that South Africa has a good comparative advantage in the production of oranges. Egypt and Greece were the competitors, with average values of 16.9 and 19.7, respectively. The South African orange industry has positive export performance, with values close to 100, which indicates that the country is a net exporter of oranges and is experiencing a sustained comparative advantage. The RTA index values were mostly positive.

The Impact of Dish Innovation on China's Intangible Cultural Heritage Economy

In recent years, the food industry has proven to be a crucial driver of economic development. However, it has been greatly affected by the impact of the epidemic. Nevertheless, with the rising vaccination rates and the implementation of effective prevention and control measures, it is gradually picking up momentum and presenting a new opportunity for a food craze. The prolonged lockdowns have led to a surge in consumer demand for food, creating unprecedented levels of desire. As a result, food and beverage companies are actively engaging in innovation and adjusting their strategies to meet market demands. The government has also played a role in supporting the industry's recovery by introducing various measures, such as rent reductions, tax cuts, fee reductions, and loan support. Additionally, technology has made a significant contribution to the recovery process. The implementation of intelligent ordering systems, mobile payments, and fresh food delivery has not only made the food industry more convenient but also enhanced its operational efficiency and customer experience. The combination of government efforts and the application of technology is assisting the food industry in recovering and growing.

Productive Performance of Biomass Sorghum (Sorghum bicolor (L.) Moench) and Cowpea (Vigna unguiculata (L.) Walp) Cultivars in Different Cropping Systems and Planting Times

Global projections indicate that the demand for fresh water, energy, and food will increase significantly in the coming decades under the pressure of population growth, economic development, climate change, and other factors. Faced with this, technologies that promote sustainable development through the use of clean energy will be imperative. That way, this study aimed at evaluating the productive performance of biomass sorghum and cowpea cultivars in different cropping systems and planting seasons. The experiment was conducted at the Caatinga Experimental Field at Embrapa Semiarid, Petrolina—PE. Four cowpea (BRS Itaim, BRS Gurguéia, BRS Guariba, and BRS Carijó) and two biomass sorghum cultivars (BRS 716 and AGRI-002E) were used in intercropping and monoculture systems. The cultivars were sown during two different seasons: June (season 1—winter) and December (season 2—summer) of 2021. The biometric and productive parameters and land equivalent ratios (LERs) of sorghum and cowpea were evaluated. The data were subjected to multivariate analysis. The productive performance of biomass sorghum cultivars Agri-002E and BRS 716 was higher when planted in December, with an increase of 37% due to the planting season. Cowpea productivity was not influenced by sowing seasons or the cultivation system. Based on the calculation of efficient land use, the intercropping between biomass sorghum cultivar BRS 716 and cowpea cultivars BRS Gurguéia, BRS Guariba, and BRS Carijó was advantageous when compared to monocultures planted in the hottest season. This study showed the importance of cultivar selection, the planting time, and land use efficiency in intercropping systems.

Construction of “ant-like tentacle” structure for ultra-sensitive detection of low-concentration ammonia through colorimetric fluorescent dual-signal gas-sensitive cotton fabric

Detection and monitoring of ammonia (NH3) are crucial in various industries, including plant safety management, food freshness testing, and water pollution control. Nevertheless, creating portable, low-cost, highly sensitive, and easily regenerated ppm-level NH3 sensors poses a significant challenge. In this investigation, an innovative “ant-like tentacle” fabrication strategy was proposed, and a colorimetric fluorescent dual-signal gas-sensitive cotton fabric (PAH-fabric) for NH3 detection was successfully prepared by conventional dyeing using suitable molecular-level photoacid (PAH) sensitive units. The visual recognition lower detection limit of the ultra-low is 1.09 ppm-level. PAH-fabric is not only straightforward, convenient, and cost-effective to prepare, but it can also be efficiently regenerated and recycled multiple times (maintaining excellent gas-sensitive performance even after 100 cycles) by strategically leveraging volatile acid fumigation. Detailed molecular reaction mechanisms involved in the NH3 response and PAH-fabric regeneration are elucidated. PAH-fabric, available either as a portable kit or an alarm system, offers a promising approach for ultra-low NH3 detection. The demonstrated “ant-like tentacle” fabrication strategy introduces numerous possibilities for designing and developing sensors with adjustable response thresholds, particularly those requiring high sensitivity.

Public Urban Agriculture Equipment: A Tool for Fair and Sustainable Food Policies? Potager du Roi and Cité Maraîchère, Two French Case Studies

Over the past few decades, a large variety of urban farms and projects have developed in the Global North. Urban agriculture addresses numerous challenges such as producing sustainable fresh food, educating people, and creating new jobs and skills. Urban agriculture is diverse in terms of location (rooftop, basement, underground, parking), activities (food production and/or services), and techniques (from low-tech to high-tech). These projects are created by entrepreneurs because they live in the city, want to change their environment, and promote sustainable practices. Faced with economic and environmental crises, public authorities at different levels and with various orientations reorganize the food system towards local production and consumption; they encourage the development of urban agriculture through a diverse range of policies. These public projects must be economically viable but can be created as socially oriented services based on food production and not only as sites of food production. Our empirical research based on the case studies of two original public urban farms, the Potager du Roi de Versailles and the Cité Maraichère de Romainville, uses the concept of the triple layered business model and highlights their sustainable strategy. Our evaluation of their economic, social, and environmental impacts tends to demonstrate not only their dependence on multiple interlinked public policies but also the justification of significant and recurring public funds for the general interest.

Community gardens support high levels of food production, but benefit distribution is uneven across the gardener community

Urban community gardens are important social–ecological systems from which urban citizens receive many benefits. In this study of 18 urban community gardens in the Central Coast of California, USA, we use a combination of gardener surveys and field-based measurements to evaluate the amount of fresh fruit and vegetables produced by gardeners. We then investigate how food production differed between segments of the gardening population, specifically as a function of gardening experience, time spent in gardens, and food security status. Lastly, we ask gardeners to describe their motivations for gardening to better understand how motivations may relate to individual levels of food production. Thirty-eight percent of gardeners estimate harvesting one to five pounds of food per week, with another 26% estimating six to ten pounds. These estimates were corroborated by field measurements of tomato, squash, and pepper cultivation, where gardeners produced, at the height of the harvest season, an average of four pounds of food per week—an estimated savings of ~ $16USD per week (compared to the cost of local organic fruits and vegetables, June 2023 prices). Regarding the ability of community gardens to reduce food insecurity, gardeners who spent more time in the garden and with higher incomes reported higher food security, while those with larger families or lower incomes were more food insecure. These results show that gardeners in most need of food support were not necessarily the ones cultivating the most fruits and vegetables. While 48% of gardeners reported food cultivation as a primary motivator for gardening, many other motivations (e.g., hobby, being outdoors, relaxation, social interaction, and exercise) were identified as reasons to spend time in the garden, indicating that food production is not the only factor motivating gardeners. Overall, we document that community gardens can be highly productive and provide valuable produce that substantially offsets high fresh food costs; however, gardeners with the greatest food needs are currently not the largest producers, but could benefit from additional resources and support.

Antimicrobial and antioxidative electrospun cellulose acetate-essential oils nanofibrous membranes for active food packaging to extend the shelf life of perishable fruits

Food preservation is critical to meeting the growing demand for fresh foods. We construct novel active packaging using active chemicals to extend the shelf life of fresh fruit and vegetables. In our study, we harnessed electrospinning technology to manufacture cellulose acetate nanofibers (CANFs) using natural, highly volatile cinnamon bark oil (CNO) and clove bud oil (CBO). The CNO and CBO loaded electrospun fibers were characterized and applied as active packaging membrane to evaluate the impact on shelf life of fresh grapes and tomatoes. Scanning electron microscopy (SEM), fourier-transform infrared spectroscopy (FT-IR), and gas chromatography–mass spectrometry (GC–MS) analysis indicated a uniform volatile component distribution, average fiber diameters, regulated release kinetics, and substantial antioxidant, and antibacterial activities. The use of 50 % w/w CNO and CBO-loaded CANFs as an active food packaging membrane for a shelf-life study of fresh grapes and tomatoes at 4 °C confirmed the microbiological safety of consumption for 40 days compared to 15 days in control samples, with a lesser reduction in physiochemical properties despite sensory evaluation revealing a shelf-life extension until 30 days.The efficacy and potential benefits of sustainable and effective packaging strategies are highlighted in this study, making it a promising alternative for preserving perishable tomatoes and grapes.

Effects of freeze–thaw pre‐treatment with different freezing methods on the microwave freeze drying of carrots

SummaryThree freeze–thaw (FT) pre‐treatments using different freezing methods that freezing at −80 °C (FT‐80), freezing at −25 °C (FT‐25) and vacuum freezing (VFT) were used for carrot slices, the effects and mechanisms of FT pre‐treatment on the drying characteristics and product quality of carrots during microwave freeze drying (MFD) were studied. The results showed that FT pre‐treatment under different freezing methods affected the water state of carrots, resulting in varying degrees of moisture loss and shortening drying time by 14.3% to 42.8%. VFT treatment caused the greatest water loss (35.33%) during FT and significantly increased the effective moisture diffusivity in the MFD process. FT treatments did not cause any significant degradation in the colour of the carrots. The VFT and FT‐80 treatments resulted in an elevated rehydration ratio, increased crispiness of MFD carrots and products with a porous microstructure and higher porosity. In contrast, the FT‐25 treatment led to a decrease in porosity due to destructive damage to the carrot cell structure. However, this damage favoured the extractability of carotenoids, resulting in a higher carotenoid content than the other treatments. This study provides a theoretical foundation for the practical implementation of FT pre‐treatment using various freezing methods on fresh foods prior to drying. It is recommended to employ VFT pre‐treatment before MFD due to its efficiency and effectiveness.

Experimental Comparison of Two 6D Pose Estimation Algorithms in Robotic Fruit-Picking Tasks

This paper presents an experimental comparison between two existing methods representative of two categories of 6D pose estimation algorithms nowadays commonly used in the robotics community. The first category includes purely deep learning methods, while the second one includes hybrid approaches combining learning pipelines and geometric reasoning. The hybrid method considered in this paper is a pipeline of an instance-level deep neural network based on RGB data only and a geometric pose refinement algorithm based on the availability of the depth map and the CAD model of the target object. Such a method can handle objects whose dimensions differ from those of the CAD. The pure learning method considered in this comparison is DenseFusion, a consolidated state-of-the-art pose estimation algorithm selected because it uses the same input data, namely, RGB image and depth map. The comparison is carried out by testing the success rate of fresh food pick-and-place operations. The fruit-picking scenario has been selected for the comparison because it is challenging due to the high variability of object instances in appearance and dimensions. The experiments carried out with apples and limes show that the hybrid method outperforms the pure learning one in terms of accuracy, thus allowing the pick-and-place operation of fruits with a higher success rate. An extensive discussion is also presented to help the robotics community select the category of 6D pose estimation algorithms most suitable to the specific application.

In situ growth of curcumin-loaded cellulose composite film for real-time monitoring of food freshness in smart packaging

Visual pH-responsive packaging material is particularly important in food supply chain safety monitoring due to their non-destructive monitoring method and intuitive result. However, it has always been limited by the instability performance of pH-response components and carriers, which further hinders its wide food safety application. To address these challenges, we selected cellulose with remarkable biocompatibility and mechanical properties as the carrier, and high pH-responsive curcumin to develop a smart packaging material (RC/GC composite film) with real-time food safety monitoring. Compared with pure cellulose film, the RC/GC composite film exhibited excellent mechanical properties (4-fold enhancement) and thermal stability (100 °C increasing). Meanwhile, based on the first reported strategy of curcumin in-situ growth during cellulose film formation, the RC/GC composite film exhibited exceptional antioxidant activity (89.2 %), antimicrobial property (91.6 %), and significant pH-responsive sensitivity (within 15 s). This innovative approach offers a new strategy for easy-to-use and effective monitoring of food spoilage in packaging materials.

Optimized hybrid edible surface coating prepared with gelatin and cellulose nanofiber for cherry tomato preservation

The use of renewable bioresources and their nanoforms in developing edible coating materials is considered a promising approach for preserving food freshness. Herein, cellulose nanofibers (CNF) with different morphologies were combined with gelatin to prepare composite preservation film following by brushing over the surface of cherry tomatoes as an edible coating. The gelatin-based composite film containing 0.3 % CNF20 (GC2–0.3) exhibited the lowest water vapor permeability (WVP, 1.97 × 10−4 barrer), lower oxygen permeability (OP, 2.54 × 10−2 barrer), higher transparency (Tr = 85.28 %) and excellent mechanical properties (σ = 47.45 MPa, E = 1.84 GPa). When coated on cherry tomatoes, it maintained good luster and freshness, significantly reducing the water loss of cherry tomatoes. The weight loss was only 16 % after 14 days of storage at 25 °C and 30 % humidity, compared to >30 % for the uncoated cherry tomatoes. This work provides a viable strategy for developing sustainable, green fresh-keeping materials that can prolong the storage time of the putrescible food.

Multifunctional intelligent indication labels featuring antibacterial properties based on pectin/carboxymethyl chitosan incorporated with porous microspheres loaded with anthocyanins: A new approach for salmon preservation and freshness detection

Multifunctional intelligent indication labels tend to prolong the quality guarantee period and monitor the freshness of food. In this study, indication labels were prepared with carboxymethyl chitosan (CMCS) and pectin as substrate, and porous microspheres loaded with anthocyanins (ACN@PGMs) as indicators and antioxidant as well as clove essential oil as an antibacterial agent. The interaction between pectin and CMCS and the addition of ACN@PGMs improved the physical properties and structural density of indication labels due to electrostatic complexing and hydrogen-bonding interactions, which exhibited optimal performance when the added anthocyanins equivalent was 0.25 mg/mL. Meanwhile, the water contact angle and antibacterial activity reached maximum values of 78.8 ± 2.3°, 11.8 ± 0.88 cm (E.coli), and 17.00 ± 0.71 cm (S.aureus), respectively. In addition, indication labels displayed sensitive color responses to different pH and ammonia environments. In application, labels could extend the shelf life of refrigerated salmon from 4 days to 9 days and showed significant color changes when salmon spoiled. Overall, indication labels played a positive role in extending shelf life and visual freshness detection, which could be employed in food quality evaluation and food preservation.

Advancements in Gellan Gum-Based Films and Coatings for Active and Intelligent Packaging.

Gellan gum (GG) is a natural polysaccharide with a wide range of industrial applications. This review aims to investigate the potential of GG-based films and coatings to act as environmentally friendly substitutes for traditional petrochemical plastics in food packaging. GG-based films and coatings exhibit versatile properties that can be tailored through the incorporation of various substances, such as plant extracts, microorganisms, and nanoparticles. These functional additives enhance properties like the light barrier, antioxidant activity, and antimicrobial capabilities, all of which are essential for extending the shelf-life of perishable food items. The ability to control the release of active compounds, along with the adaptability of GG-based films and coatings to different food products, highlights their effectiveness in preserving quality and inhibiting microbial growth. Furthermore, GG-based composites that incorporate natural pigments can serve as visual indicators for monitoring food freshness. Overall, GG-based composites present a promising avenue for the development of sustainable and innovative food packaging solutions.

A versatile pH-sensitive hydrogel based on a high-performance dye: Monitoring the freshness of milk and chicken meat

There is a growing interest in soft-matter sensors at the research and application level. Colorimetric hydrogel-based sensors can work as smart tools for the fast, simple, and low-cost monitoring of food freshness and spoilage. Herein we developed a hydrogel pH indicator working from pH 2–12 with a specific colorimetric pattern. A fast-responsive, easily formed and mouldable hydrogel was obtained by adding a minimal amount of a single pH-sensitive dye to an agar matrix. Optical, mechanical, and morphologic characteristic of the hydrogel were examined in detail. An easy-to-use smartphone app ensures color tone capture and correlation of color changes to pH levels. Practical applications of the versatile gel sensor were tested in solution and in the gaseous phase. The sensor was employed to assess the freshness of milk samples and to monitor the volatile basic nitrogen compounds resulting from packaged chicken spoilage.

Extension of chicken fillets shelf life using genetically improved probiotic strain and chitosan

Fresh poultry meat products are perishable and need to be protected from spoilage. New or modified preservation techniques are needed to overcome the limitations of the traditional techniques. Therefore, six different coating solutions were evaluated to extend the shelf life of chicken fillets under refrigeration condition. The novel chitosan-based mix (T6) containing a bacteriocins-hyperproducer fusant, EDTA and sodium acetate was the treatment of choice since it improved film properties such as the reduction of water vapor permeability and the enhancement of the antimicrobial effect. Coating chicken fillets with the T6 mix resulted in improving both of the quality and shelf life of fillets. T6 recorded the lowest TBA value (1.25) compared to 4.77 mg malondialdehyde Kg−1 of the control at the end of the cold storage. Also, it extended the microbial shelf life up to 35 days by extending both of the lag phase and generation time of spoilage microorganisms by 6 days and 44.31 h, respectively. At the same time, T6 samples exhibited the highest sensory scores. It is strongly believed that such novel preservation system could be easily applied to extend the shelf life of many of the fresh foods since it was successfully applied to extend the shelf life of fresh chicken fillets by more than 31 days compared to control with high quality.

The Application of Hydrogen Sulfide Fluorescent Probe in Food Preservation, Detection and Evaluation.

This work primarily reviewed the response mechanism of fluorescent probes for H2S detection in foodstuffs in recent years, as well as the methodologies employed for detecting foodstuffs. Firstly, the significance of studying H2S gas as an important signaling molecule is introduced. Subsequently, a review of the response mechanism of the scientific community on how to detect H2S in foodstuffs samples by fluorescent probe technology is carried out. Secondly, the methods commonly used for detecting foodstuffs samples are discussed, including the test strip method and the spiking recovery methods. Nevertheless, despite the significant advancements in this field, there remain some research gaps. Finally, the article identifies the remaining issues that require further attention in current research and proposes avenues for future investigation. More importantly, this work identifies the current limitations of research in this field and proposes future applications of fluorescent probes for H2S in assessing food freshness and determining food spoilage. Therefore, this review will provide robust technical support for the protection of consumer health and the advancement of the sustainable development of the food industry and also put forward some new ideas and suggestions for future research.

Recent progress in properties and application of antibacterial food packaging materials based on polyvinyl alcohol

Abstract Polyvinyl alcohol (PVA) is well-known for its excellent mechanical properties and eco-friendliness in food packaging. Recently, PVA has gained significant attention in research due to its potential as antibacterial substrates. However, because of its high hydrophilicity, practical application of pure PVA film has been limited by low water resistance and rapid bacterial growth in humid conditions. Diverse effective strategies have been developed to decrease hydrophilicity and endow films with antibacterial properties. This review provides an overview of universal antibacterial agents and their functions in PVA-based packaging films. It also introduces the changes in the mechanical and physical properties of PVA-based films after adding antibacterial agents. Additionally, the release behavior of antibacterial agents in PVA-based film materials and their practical applications in the food industry is discussed in fresh food packaging. Biodegradability of PVA-based films is also mentioned, with a promising future for more effective and eco-friendly food packaging materials.

Research on Vegetable Pricing and Replenishment Model Based on Greedy Algorithm

This article analyzes the pricing and replenishment decisions of supermarkets, exploring the distribution patterns and correlations between different vegetable categories and individual products. On the other hand, a robust linear programming model is constructed, which can iteratively optimize the corresponding replenishment plan, significantly improving the profitability of supermarkets. This provides important practical significance for the operation and sales of vegetable products in fresh food supermarkets. Through Spearman correlation coefficient analysis, it was found that there is a close relationship between cauliflower and leafy vegetables. The correlation between various vegetable items was processed using K-means clustering method, and the correlation between each item was discussed after classifying the groups. Finally, the grey correlation analysis method was used to further explore the ranking of the correlation between each category and individual product.

Highly stable and multifunctional intelligent film based on grape skin anthocyanin, polyvinyl alcohol, chitosan and selenopeptide: Preparation, characterization and application

Highly stable and multifunctional intelligent films were fabricated using a combination of grape skin anthocyanin, polyvinyl alcohol, chitosan and selenopeptide, and the influence of selenopeptide concentration on films' properties and their effectiveness in strawberry preservation and freshness monitoring was investigated. The results showed that the incorporated selenopeptide could interact with polyvinyl alcohol and grape skin anthocyanin via hydrogen bonding, improving the hydrophobic, UV-blocking, and mechanical characteristics of the films. In particular, the introduction of 0.4% selenopeptide into the film notably boosted its tensile strength from 11.91 MPa to 26.91 MPa. More importantly, the films incorporated with selenopeptide showed decent antioxidant and antibacterial properties, along with high storage stability and thermal stability. Adding 0.4% selenopeptide to the film can increase the shelf life of strawberries at 25 °C by 3 days, and a distinct color change showing fair good linear relationship with the freshness indexes of the strawberry (hardness and weight loss rate) was observed. Overall, anthocyanin-infused films combined with selenopeptide have demonstrated promising results in preserving food and monitoring freshness, opening up new opportunities for preparing stable, smart and active films.

Consumer Perception of the Performance of Online Catering Food Safety Regulations: The Case of Shanghai, China.

To protect the safety of food bought from the online catering sector, the former State Food and Drug Administration of China issued two separate regulations in 2016 and 2017. Independently, the Shanghai government formulated local regulations, including the Shanghai Online Catering Service Supervision and Management Measures, to strengthen food safety supervision in this megacity with the largest catering sector in China. This study explored factors that influence consumer perceptions of the performance of online catering food safety regulations using survey data from 1050 respondents collected in 2019. The results indicate that consumers believe that Shanghai's online catering industry has improved by varying degrees in terms of food freshness, ingredient traceability, foreign matter control, food temperature control, internal packaging hygiene and environmental protection, and satisfaction with food safety. The factors that influenced the listed features include the number and effectiveness of government-issued regulations regarding the online catering sector, effectiveness of ordering platform food safety regulations, employee training frequency, employee food safety awareness, delivery box cleanliness and courier personal hygiene, consumer trust in ordering platform services, and consumer confidence in government supervision. These factors significantly and positively affected the consumers' perceptions of the performance of food safety regulations in the online catering sector.