Postharvest Stage Research Articles

Perancangan Mesin Perontok Tandan Buah Kelapa Sawit Yang Restan

Threshing is the post-harvest handling stage after the harvesting process. Threshing is an integral part of the palm post-harvest handling process. The harvested oil palms are threshed to separate the fruit from the bunches. The threshing process is carried out so that small oil palm fruits or oil palm fruit bunches weighing below 5 kg can be accepted at the palm oil mill. Generally, the weight of fresh fruit bunches (FFB) under 5 kilograms is not sold, so before being taken to the palm oil mill, it must be threshed first so that the palm oil becomes brondolan or grains of palm oil that can be accepted by the palm oil mill. In this final project, the author designed a small oil palm fruit threshing machine from the bunches aimed at increasing the profits of farmers or oil palm entrepreneurs, because small oil palm fruits can be accepted at palm oil mills. In this design, the driving engine uses a fuel motor motor with a power of 7 HP.

Natural fermentation with delayed inoculation of the yeast Torulaspora delbrueckii: Impact on the chemical composition and sensory profile of natural coffee

All coffee production stages occur in a microbiome, which is generally composed of bacteria, yeasts, and filamentous fungi. The use of starter cultures in post-harvest processing stages is an interesting alternative, since they promote faster removal of mucilage and incorporation of compounds that improve sensory quality, which can result in diverse sensory attributes for the beverage. This study was therefore developed with the objective of evaluating the effect of the following processing procedures on the chemical and sensory characteristics of the coffee beverage: first, fermentation of coffee fruit of the yellow Catucaí variety of Coffea arabica with indigenous microorganisms, followed by inoculation of the starter culture Torulaspora delbrueckii CCMA 0684 during the drying stage. The fruit was divided into two lots, which were differentiated by a natural fermentation process before drying began. The starter culture was inoculated on the coffee at different times during the drying process: at 0 h, 24 h, 48 h, or 72 h after drying began. The sensory attributes, the volatile compound composition of the roasted beans, the organic acid profile, the bioactive compounds, and the fatty acid profile of the green coffee beans were analyzed. The fatty acid and bioactive compound content showed little variation among treatments. Analysis of volatile compounds and organic acids and evaluation of sensory attributes made it possible to distinguish the two treatments. We conclude that natural fermentation of coffee fruit improve the chemical and sensory quality of the coffee beverage. The effect of natural fermentation may be before inoculation of the starter cultures or even during drying.

Synthesis and application of Ag-doped TiO2 nanoparticles with antifungal activity and ethylene inhibition in postharvest of avocado cv. Hass

Avocado is highly susceptible to postharvest diseases and rapid ripening, making it challenging to maintain its quality and shelf life. One potential solution is the use of nanoparticles that can act as both antimicrobial agents and ethylene inhibitors. In this study, we synthesized Ag-doped TiO2 nanoparticles through a solution combustion method and subjected them to various characterization techniques, including X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. These nanoparticles were then tested for their effectiveness in combating common avocado pathogens and their ability to inhibit ethylene production. To apply our findings practically, we treated Hass avocado fruits in the postharvest stage with a suspension of Ag-doped TiO2 nanoparticles and stored them under controlled conditions to simulate the ripening process. The Ag-doped TiO2 nanoparticles formed agglomerates within the nanometric range and exhibited oxidation-reduction characteristics, effectively inhibiting ethylene production and degrading Rhodamine-B dye. Moreover, these nanoparticles displayed robust antimicrobial activity, significantly suppressing the growth of Colletotrichum gloeosporioides sensu lato pathogens. Treated fruits in the postharvest phase showed reduced microbial growth, decreased incidence of anthracnose, stem and root diseases, and an extended shelf life compared to the control group, due to ethylene inhibition. Ag-doped TiO2 nanoparticles, with their dual capabilities of antimicrobial activity and ethylene inhibition, show promise in improving postharvest management of Hass avocados. They have the potential to enhance fruit quality, reduce postharvest losses, and improve marketability. Further research and field trials are essential to fully explore the practical applications of these nanoparticles in commercial avocado production and distribution.

Physical, Sensorial, and Physicochemical Characteristics of Arabica Coffee Dried under Two Solar Brightness Conditions

The solar drying process is a critical postharvest stage for preserving coffee quality and is widely used in coffee-producing countries. A descriptive exploratory study was carried out in zones with different annual solar brightness to determine the climate variability influence on solar drying. Variables related to the evolution of drying, physical and sensory quality, and the physicochemical characteristics of the Castillo® coffee variety were analyzed. Coffee quality was assessed by means of SCA protocol. An automatic system was designed to record variables inside the dryers and mass loss. The drying rates were different by climatic zone above and below 0.52%∙h−1. Drying time was significantly longer in less solar brightness zones (Wilcoxon test). An inverse linear relationship between rewetting percentage and bean moisture was observed. Regarding coffee quality, the average scores were 81.37 and 80.93 SCA points for the climatic zones with the lowest and highest solar brightness, respectively. The bean color, water activity, acidity, and fat content did not vary between climatic zones. The coffee quality was not affected by solar drying in contrasting climatic conditions, despite the differences in drying time. Solar drying behaviors were identified that allow for the development of strategies for improving the process efficiency and management of coffee.

Study on the mechanism of local compression bruising in kiwifruit based on FEM

AbstractThis study focuses on the relationship between local compression and local bruise volume of kiwifruits by means of finite element method (FEM). The effects of four indenter shapes and three compression directions on the local kiwifruit bruise were considered. The local bruise volume and the irregular cross section area of kiwifruit were calculated. Multi‐scale kiwifruit 3D modelling based on irregular cross‐sectional area computed by slice‐integration method. Local compression bruise was simulated by FEM. The results of the local bruise test show that the contact force and the bruise volume of kiwifruit are positive linear correlation. Comparing the simulation with the experimental, the mean absolute percentage error (MAPE) of the reconstructed model is 0.0394, and the R2 of contact force–bruise volume curve is 0.8203. The maximum equivalent forces and abrasions occur in the 0° and 90° loading directions with the square indenter has been showed by FEM results.Practical applicationsSe‐enriched kiwifruit has high nutrition and economic value. Kiwifruits are often influenced by a variety of factors and processes from harvest to consumption time. Cleaning, transport, and various processing operations including peeling and slicing in the kiwifruit industry are responsible for local bruise to kiwifruit. Therefore, understanding the mechanism of local bruise caused by local contact force of kiwifruit plays an important role in reducing kiwifruit waste in the postharvest stage. Local bruise mechanisms can be used in harvesting and post‐harvest mechanical design and product transportation and positioning equipment.

Enzymatic tissue browning caused by biological membrane degradation in the young immature fruit of ‘Moriya’ persimmon (Diospyros kaki Thunb.)

Determining the mechanism of fruit tissue browning is important to prevent fruit quality degradation and reduce fruit loss at the postharvest stage in persimmons. We aimed to provide a fundamental understanding of the mechanism of browning of mature persimmon fruit and contribute to develop a method for its prevention over the course of the marketing supply chain by analyzing the browning of young immature persimmon fruit. Tissue browning was first observed seven days after harvest (DAH), and spontaneous ethylene production was initiated at five DAH. The activities of the browning enzymes polyphenol oxidase (PPO) and peroxidase (POD) were sufficiently high to induce fruit tissue browning. As these enzymes are normally sequestered by biological membranes in cells, we hypothesized that biological membrane degradation occurs prior to browning. Electrolyte leakage and the increase in malondialdehyde content occurred during storage. An increase in malondialdehyde content provided evidence of progressive membrane degradation. The increased expression of phospholipase relative DkPLD alpha1, DkPLD beta/gamma1, and lipoxygenase relative DkLOX3 genes, probably induced by ethylene, indicated their significant roles in membrane degradation. The ascorbic acid may play a role in inhibiting the oxidation of phenolic substrates by PPO and POD owing to its antioxidant activity. The results of our study suggest that the hydrolysis of phospholipids by DkPLD alpha1 and DkPLD beta/gamma1 and peroxidation by DkLOX3 promote biological membrane degradation in both persimmon skin and flesh. Additionally, we hypothesized that the decrease in L-ascorbic acid content could induce browning, as a result of PPO and POD leaked from the biological membrane could react with phenolic substrates.

Regulated and Emerging Mycotoxins in Bulk Raw Milk: What Is the Human Risk?

Mycotoxins are abiotic hazards whose contamination occurs at the pre- and post-harvest stages of the maize value chain, with animal exposure through contaminated feed leading to their excretion into milk. Currently, only aflatoxin M1 is regulated in milk products. Since feed materials and complete feed present a multi-mycotoxin composition and are the main mycotoxin source into milk, it is important to recognize the occurrence of multiple toxins and their co-occurrence in this highly consumed food product. The aim of this study was to determine the content of regulated and emerging mycotoxins in milk samples, which allowed for evaluating the occurrence and co-occurrence patterns of different mycotoxins known to contaminate feed materials and complete animal feed. Human exposure considering the occurrence patterns obtained was also estimated. Aflatoxins, fumonisins, zearalenone, and emerging mycotoxins were among the mycotoxins found to be present in the 100 samples analyzed. Concentrations ranged from 0.006 to 16.3 μg L-1, with no sample exceeding the AFM1 maximum level. Though several mycotoxins were detected, no exceeding values were observed considering the TDI or PMTDI. It can be concluded that the observed exposure does not pose a health risk to milk consumers, though it is important to recognize vulnerable age groups.

Assessing the impacts of COVID-19 pandemic on agricultural and food systems in Badulla District, Sri Lanka

Despite the health condition, the global pandemic COVID-19 resulted in various negative impacts such as threats to the sustainability of agricultural and food systems on a global scale. It is therefore necessary to analyse and comprehend the immediate consequences of current pandemic on agricultural and food systems in order to develop necessary actions. This study was carried out to assess the impact of COVID-19 pandemic on agricultural and food systems in Badulla district, Sri Lanka where the study was conducted in four Agriculture Instructor (AI) regions namely Badulla, Bandarawela, Welimada and Mahiyangana, from September 2020 to March 2021. AI regions were selected using cluster sampling technique and data were collected from randomly selected 209 farmers by administering a structured questionnaire. Data were analysed using quantitative techniques and text analysis. Results revealed that the key issue faced by the farmers was marketing and distribution. Other main problems were associated with labor, quality raw-material, finance, prices of the raw-material and quality degradation at postharvest stage including storage. Importantly, farmers have received enough farming consultancy during the pandemic. The majority of the farmers had not attempted any innovative approach to mitigate these issues but some farmers had adopted temporary solutions. In conclusion, innovative approaches in making farmers more engaged in risk management similar to COVID-19 pandemic are needed in future.

Molecular characteristics of some Botrytis isolates and antagonistic activity of Bacillus subtilis and its bacteriocin on tomato fruit

Gray mold, caused by Botrytis cinerea, is one of the most devastating agricultural diseases during the pre and postharvest stages. This study aims to investigate the application of Bacillus subtilis as a bioagent against B. cinerea and reducing pre and postharvest disease as a replacement method to chemical pesticides. Five Botrytis isolates were molecularly confirmed and the virulent isolate BC2 was registered for the first time in the National Center of Biotechnology Information (NCBI) with accession number OP257237. The mycelial growth of B. cinerea was inhibited by up to 84% when treated with the bio agent bacterium using the double drawing method in Petri plates. Pre-harvest application of B. subtilis at a concentration of 108/ml CFU reduced postharvest -gray mold of tomato fruit during ripening stages in the greenhouse. Preharvest application of bioagent bacterium B. subtilis induced the levels of B-1, 3-glucanase and Polyphenol oxidase, indicating enhanced plant resistance to gray mold. Disease severity was decreased compared with control and extended the shelf life at 25 °C.The field application of the bio agent bacterium at the maturity of ripening in preharvest had a significant effect on increasing the level of polyphenol oxidase PPO and B-1, 3-glucanase, which are related to the enhancement of plant defenses and resistance. Additionally, it led to an increase in storage life and a reduction in post-harvest losses. The results demonstrated that preharvest application of bio agent bacterium Bacillus subtilis improved the quality of postharvest tomato fruit and significantly reduced gray mold incidence, all without the use of chemical pesticides.

Effect of post-harvest management practices on the mycobiome and ochratoxin A contamination of differently processed Robusta coffees from Ivory Coast

Ochratoxin A (OTA) is a secondary metabolite produced primarily by the genus Aspergillus sp. sections Circumdati and Nigri. It can accumulate in coffee at post-harvest stage. In the present study five different dry processed coffees were sampled from Ivory Coast at harvesting and after drying. The OTA was detected in all the samples, from 3.62 μg/kg of coffee just after harvest to a higher-level of contamination in the dried coffee, between 11.04 and 760.24 μg/kg of coffee. Metabarcoding was used to further study the changes in the mycobiota. The alpha and beta diversity analysis revealed the presence of unique and more diverse fungal communities on the coffee after drying compared to fresh harvested coffee. Specially, coffee dried for a longer period showed a higher diversity. Fungal species such as Hypopichia sp. or Bernettozyma sp., were replaced in the top ten abundant species after drying by species such as Kurtzmaniella sp., Meyerozyma sp. and Fusarium sp. The increasing abundance of the ochratoxigenic fungi, A. carbonarius was correlated to the increased concentration of OTA on coffee. The construction of the negative correlation network shows that some yeasts could be good candidates for the biocontrol of A. carbonarius. The combination of DNA metabarcoding and OTA quantification was effective at deciphering the post-harvest origin of the OTA contamination. Overall, this study highlights the changes in the mycobiota under different drying conditions. Future perspectives include developing actions of prevention and control of the contamination with OTA during the post-harvest stages.

Potential utility of endophytic Bacillus altitudinis strain P32-3 as a biocontrol agent for the postharvest prevention of sweet potato black rot

Sweet potato black rot is a common postharvest disease caused by the pathogenic fungus Ceratocystis fimbriata. The toxins produced by infected tubers are potentially harmful to humans. Plant endophytic bacteria may serve as biocontrol agents for protecting crops (including vegetables) during postharvest storage without detrimental effects on humans or other animals. In this study, 11 bacterial strains of Bacillus, Priestia, Blautia, Pseudomonas, and Sphingomonas species were isolated from sweet potato storage roots, of which only one strain (P32-3), which was identified as Bacillus altitudinis, strongly inhibited C. fimbriata mycelial growth and spore germination. Furthermore, the volatile organic compounds and cell-free supernatant of strain P32-3 repressed C. fimbriata growth. Additionally, P32-3 treatments significantly decreased the disease spot diameter and depth on harvested sweet potato roots. A total of 981 differentially expressed genes were identified by comparing the transcriptomes of the control and P32-3-treated mycelia. Strain P32-3 significantly altered the expressions of genes related to cell wall integrity, the cell membrane, spore germination, energy metabolism, pathogenicity, and oxidative stress. In addition, RNA-seq results were validated by a quantitative real-time polymerase chain reaction analysis. Our results indicate that B. altitudinis strain P32-3 can inhibit C. fimbriata growth and development and protect postharvest sweet potato storage roots from C. fimbriata infection. The study findings provide the theoretical basis for future investigations on the utility of strain P32-3 for protecting sweet potato against black rot during the postharvest stage.

Environmental Impact Analysis to Achieve Sustainability for Artisan Chocolate Products Supply Chain

Small-scale artisan chocolate producers target environmentally conscious consumers and must work with their supply chain partners to measure and improve their environmental impacts. This research evaluates the environmental impact along the supply chain of artisan dark chocolate products in Indonesia and creates an action plan to reduce environmental impact. The Life Cycle Assessment (LCA) methodology was used. The analysis considers cocoa production from the farm level to the processing of cocoa beans into bars in three stages for 1 kg of dark chocolate: the farm maintenance and harvesting stage; post-harvesting stage; and processing stage. At the farm maintenance and harvesting stage, the significant contributions are 72.5% of total abiotic depletion (AD), 47.2% of total global warming (GW), 80.2% of total eutrophication (EU). The significant contributions at the post-harvesting are 31.2% of total AD, 51.8% of total GW, 83% of total EU, 26.4% of total ozone layer depletion (ODP), 20.1% of total cumulative energy demand (CED) and non-renewable fossil (NRF), and 36.9% of total CED renewable biomass (RB). And at the processing stage, the significant contributions are 20.5% of total AD, 15% of total GW, 4% of total ODP, 13.1% of total acidification (AC), 12% of total EU, 10% of total fossil resource scarcity (FRS), and 1.6% of total CED NRF. Changes to the farm maintenance and harvesting stages contributed the most to environmental impact reduction by improving waste utilization and the treatment and selection of environmentally friendly materials.

Development of mussel-inspired chitosan-derived edible coating for fruit preservation

Fruit rotting at the postharvest stage severely limits their marketing supply chains and shelf-life. Thus, developing a green and cost-effective approach to extend the shelf-life of perishable foods is highly desired. In this study, inspired by the mussel-adhesion strategy, a multifunctional fruit coating material has been developed using a quaternized catechol-functionalized chitosan (CQ-CS) grafted with 2, 3-epoxypropyl trimethyl ammonium chloride and 3, 4-dihydroxy benzaldehyde. The as-prepared CQ-CS coating exhibited excellent mechanical properties, universal surface adhesion abilities, antimicrobial and antioxidant capacities without any potential toxicity effects. Using strawberry and banana as model fruits, we showed that the CQ-CS coating could effectively maintain the fruit's firmness and color, decrease the weight loss rate, and prevent microbial growth, thus finally extending their shelf- life when compared to uncoated samples, indicating the universal application of the as-prepared CQ-CS coating. These findings demonstrated that this novel conformal coating of CQ-CS has great potential for fruit preservation in the food industry.

Postharvest Diseases of Pomegranate: Alternative Control Means and a Spiderweb Effect.

The pomegranate is a fruit known since ancient times for its beneficial properties. It has recently aroused great interest in the industry and among consumers, leading to a significant increase in demand. Consequently, its cultivation has been boosted all over the world. The pomegranate crop suffers considerable yield losses, especially at the postharvest stage, because it is a "minor crop" with few permitted control means. To control latent (Alternaria spp., Botrytis spp., Coniella spp., Colletotrichum spp., and Cytospora spp.) and wound (Aspergillus spp., Penicillium spp., and Talaromyces spp.) fungal pathogens, different alternative compounds, previously evaluated in vitro, were tested in the field on pomegranate cv. Wonderful. A chitosan solution, a plant protein hydrolysate, and a red seaweed extract were compared with a chemical control treatment, all as preharvest (field application) and postharvest treatments and their combinations. At the end of the storage period, the incidence of stamen infections and external and internal rots, and the severity of internal decay were evaluated. Obtained data revealed that pre- and postharvest application of all substances reduced the epiphytic population on stamens. Preharvest applications of seaweed extract and plant hydrolysate were the most effective treatments to reduce the severity of internal pomegranate decays. Furthermore, the influence of spider (Cheiracanthium mildei) cocoons on the fruit calyx as a possible barrier against postharvest fungal pathogens was assessed in a 'Mollar de Elche' pomegranate organic orchard. Compared to no-cocoon fruit (control), the incidence of infected stamens and internal molds in those with spiderwebs was reduced by about 30%, and the mean severity of internal rots was halved. Spiderwebs analyzed via Scanning Electron Microscopy (SEM) disclosed a layered, unordered structure that did not allow for the passage of fungal spores due to its mean mesh size (1 to 20 µm ca). The aims of this research were (i) to evaluate alternative compounds useful to control postharvest pomegranate decays and (ii) to evaluate the effectiveness of spiders in reducing postharvest fungal infections by analyzing related mechanisms of action. Alternative control means proposed in the present work and calyx spider colonization may be helpful to reduce postharvest pomegranate diseases, yield losses, and waste production in an integrated control strategy, satisfying organic agriculture and the planned goals of Zero Hunger Challenge launched by the United Nations.

Understanding the mechanism of pathogenicity through interactome studies between Arachis hypogaea L. and Aspergillus flavus

Aspergillus flavus (A. flavus) infects the peanut seeds during pre-and post-harvest stages, causing seed quality destruction for humans and livestock consumption. Even though many resistant varieties were developed, the molecular mechanism of defense interactions of peanut against A. flavus still needs further investigation. Hence, an interologous host-pathogen protein interaction (HPPI) network was constructed to understand the subcellular level interaction mechanism between peanut and A. flavus. Out of the top 10 hub proteins of both organisms, protein phosphatase 2C and cyclic nucleotide-binding/kinase domain-containing protein and different ribosomal proteins were identified as candidate proteins involved in defense. Functional annotation and subcellular localization based characterization of HPPI identified protein SGT1 homolog, calmodulin and Rac-like GTP-binding proteins to be involved in defense response against fungus. The relevance of HPPI in infectious conditions was assessed using two transcriptome data which identified the interplay of host kinase class R proteins, bHLH TFs and cell wall related proteins to impart resistance against pathogen infection. Further, the pathogenicity analysis identified glycogen phosphorylase and molecular chaperone and allergen Mod-E/Hsp90/Hsp1 as potential pathogen targets to enhance the host defense mechanism. Hence, the computationally predicted host-pathogen PPI network could provide valuable support for molecular biology experiments to understand the host-pathogen interaction. SignificanceProtein-protein interactions execute significant cellular interactions in an organism and are influenced majorly by stress conditions. Here we reported the host-pathogen protein-protein interaction between peanut and A. flavus, and a detailed network analysis based on function, subcellular localization, gene co-expression, and pathogenicity was performed. The network analysis identified key proteins such as host kinase class R proteins, calmodulin, SGT1 homolog, Rac-like GTP-binding proteins bHLH TFs and cell wall related to impart resistance against pathogen infection. We observed the interplay of defense related proteins and cell wall related proteins predominantly, which could be subjected to further studies. The network analysis described in this study could be applied to understand other host-pathogen systems generally.

Preference of Major Stored Product Insects in Fortified Rice with Basil

As the world’s population grows, the needs for feeding it follow the same path. Considering these conditions, ensuring the quantity and quality of raw materials, such as cereals, seems imperative. Stored product insects are responsible for significant losses in the post-harvest stages of agricultural products and the available chemical methods for their control are decreasing, due to their negative impact on the environment and humans. To this end, the evaluation of the efficacy of non-chemical methods for the management of storage insects is crucial. In the present study, we conducted two trials of choice tests based on rice fortified with basil to determine its potential as a non-chemical repellent of stored product insects. In the first trial, we evaluated the repellent activity of rice enriched with basil on adults of Sitophilus oryzae, Rhyzopertha dominica, Tribolium castaneum and Oryzaephilus surinamensis, as well as on T. castaneum larvae. In the second trial, the same procedure was followed with deltamethrin-treated rice fortified with basil. The results of the first trial showed that for most of the insect species tested, the rice fortified with basil was moderately repellent, while for O. surinamensis, it was attractive. Surprisingly, in the second trial, the deltamethrin-treated rice fortified with basil showed a repellent effect on O. surinamensis adults and T. castaneum larvae, while no repellency was observed for the rest of insect species examined. Observation time was not significant for any of the insect species, combinations and trials, with the exception of the rice fortified with basil vs. Blanc combination in O. surinamensis. Our findings suggest that the use of deltamethrin-treated rice fortified with basil was effective as a repellent for O. surinamensis adults and T. castaneum larvae.

Biostimulants Improve Yield and Quality in Preharvest without Impinging on the Postharvest Quality of Hass Avocado and Mango Fruit: Evaluation under Organic and Traditional Systems

The fruit agribusiness sector is one of the most dynamic in Colombia. Within this sector, avocado and mango are of great importance, both in terms of area planted and volume exported. Increasing the productivity, quality, and postharvest life of these fruits is a priority, due to the high losses that occur in the preharvest and postharvest stages. One current alternative to achieve this are biostimulants, which have the potential to improve the productivity and quality of fruit. The objective of this work was to evaluate the effect of the preharvest application of two biostimulants on the yield and quality of avocados and mangos. The study was carried out in production systems for cv. Hass avocado (traditional and organic) and cv. Keitt mango (traditional). In each system, two treatments were evaluated: conventional and conventional + biostimulant. Under field conditions, yield and quality variables such as weight, number of fruits, visual appearance, and size were determined. In postharvest, the fruits obtained from preharvest treatments were subjected to two storage conditions (6 and 20 °C) during the ripening process. Postharvest quality variables such as respiration, ethylene rates, weight loss, color index, firmness, total soluble solids, and titratable acidity were evaluated. The results indicated that the use of biostimulants caused a significant increase (p ≤ 0.05) in the yield, number of fruits, and preharvest quality parameters of size and weight, without negatively affecting the postharvest quality of the fruits. The biostimulant increases the total weight of fruits in organic and conventional avocado by ~55 and 25%, respectively, while in mango, this figure increased by ~23%. Hence, biostimulants can be utilized to increase the productivity of fruit trees.

Microbiological Activity Affects Post-Harvest Quality of Cocoa (Theobroma cacao L.) Beans

Cocoa beans are the basic ingredient to produce chocolate and its derivatives, including cosmetics, foods, and pharmaceutical products. The quality of cocoa beans is greatly affected by post-harvest handling, especially by microbial activity involved in pre-conditioning after they are harvested, including fermentation, drying, and storage. This review aims to provide various factors that affect each stage of post-harvest cocoa beans, process mechanisms, and various latest technologies that can be used to improve the quality of cocoa beans. Microorganisms could be involved in each post-harvest stage and affect the cocoa beans’ quality. However, fermentation was one of the keys to determining the quality of cocoa beans because fermentation involved various microorganisms, such as yeast, lactic acid bacteria, and acetic acid bacteria, which were interrelated primarily to produce precursor flavor compounds. The drying and storage processes were decisive in maintaining quality, especially in preventing mold growth and other microbial contaminants. Various technologies could improve the quality of cocoa beans during post harvest, especially by adding microbial starters during fermentation. Using several technologies of vacuum drying and a controlled atmosphere during storage could maintain the quality of the cocoa beans. However, many challenges must be faced, especially those related to controlling microbial activity during post-harvest. Therefore, post-harvest technology needs to be continuously developed, especially in controlling microbiological activities to improve the quality of cocoa beans effectively.

Photodynamic Inactivation of Botrytis cinerea Spores by Curcumin—Effect of Treatment Factors and Characterization of Photo-generated Reactive Oxygen Species

AbstractBotrytiscinerea is the main cause of gray mold in a wide range of fresh produce, which causes huge losses in pre- and/or post-harvest stages and is therefore considered the second major plant pathogen globally. Since the application of synthetic fungicides is not allowed in postharvest conditions, alternative natural approaches are required to reduce the resulting spoilage. The aim of this study was to investigate the efficacy of photodynamic treatment in inactivating B. cinerea spores in vitro, for which the interactive effect of influential treatment parameters on curcumin phototoxicity was studied using an I-optimal design. Results showed that the antifungal activity of the treatment was significantly dependent on solvent, curcumin concentration, and irradiance, except for light dose. A complete photoinactivation of spores was obtained in an aqueous ethanolic environment (optimum condition: 13 μM, 31.75 mW cm−2, 19.05 J cm−2), compared to when curcumin was dissolved in medium-chain-triglyceride (MCT) oil. Furthermore, the photogeneration of superoxide anion and hydroxyl radicals was demonstrated by electron paramagnetic resonance spectroscopy, which indicates the occurrence of a type-I photodynamic reaction. These findings suggest that curcumin-based photosensitization can inhibit/reduce fungal infection, which can be employed in pre/post-harvest stages to reduce the waste caused by spoilage.

Effects of Storage Temperature at the Early Postharvest Stage on the Firmness, Bioactive Substances, and Amino Acid Compositions of Chili Pepper (Capsicum annuum L.).

The commercial and nutritional quality of chili peppers deteriorates rapidly after harvest. So far, little is known about the effect of temperature on postharvest chili pepper quality. This study elucidated the effects of two temperatures (20 °C and 30 °C) on chili peppers' postharvest firmness, flavor, and nutritional attributes. We found that compared to 20 °C, 30 °C escalated the decline in fruit firmness, capsaicin content, and dihydrocapsaicin content, while enhancing the increment in water loss and electrical conductivity, as well as total carotenoids and ascorbic acid content. The contents of most amino acids (AAs) decreased significantly during postharvest storage compared to their initial values, whether stored at 20 °C or 30 °C; however, 30 °C had a more substantial impact than 20 °C. Meanwhile, as for soluble protein and amino acid compositions, the effect of storage temperature was genotype-dependent, as reflected by differential changes in total AA contents, single AA contents, essential AA ratio, delicious AA ratio, etc., under the 20 °C or 30 °C treatments. In conclusion, our findings reveal the influence of temperature on pepper quality, showing that the storage temperature of 20 °C was better for maintaining chili quality than 30 °C from the perspective of overall commercial attributes.