Insect contamination in food products can occur during various stages of processing and storage. Estimating the timing of contamination is essential for food safety management and traceability. While forensic science has long used nucleic acid degradation in human tissues to estimate time of death, its application to food safety, particularly for tracing contamination routes of dead insects, remains underexplored.This study simulated death-inducing conditions relevant to food production—freezing, heating, and mechanical shock—and evaluated RNA and DNA persistence in insect bodies over time. Three marker genes (Ecad, Nuo1, and a mitochondrial gene) were used to quantify nucleic acid levels under different treatment and storage conditions. Nucleic acids remained stable under continuous freezing, but thawing accelerated their degradation. Heat treatment caused enzyme inactivation, which limited degradation. Mechanical shock led to gradual nucleic acid loss. DNA was consistently more abundant than RNA, suggesting its suitability as a long-term marker. Mitochondrial RNA was more persistent than nuclear RNA, likely due to higher copy numbers.These findings demonstrate that nucleic acid degradation varies with death conditions and post-death environments. Short-term detection (Day 1 to 4) is feasible with any marker, while mid-term detection (Day 7 to 14) is possible from DNA and mitochondrial RNA. This study provides foundational insights into using the persistence of nucleic acids to estimate contamination timing and supports molecular approaches for food traceability.

In this study, the effects of light and dark conditions on the expression of candidate clock genes (SoLHY, SoPRR5, and SoTOC1), photoreceptor genes (SoPHYA, SoPHYB, and SoZTL), ascorbic acid (AsA) synthesis genes (SoVTC2 and SoGLDH), an AsA degradation gene (SoAPX), an AsA regeneration gene (SoMDHAR), and AsA content of spinach during the pre- and postharvest periods were investigated. The AsA content decreased under constant dark storage, whereas the AsA content was efficiently maintained under a light/dark cycle. Gene expression with rhythmic signals confirmed by the JTK_CYCLE method (P <= 0.05) was used for the analysis of partial correlation coefficients. Strong correlations between SoLHY and SoVTC2 were observed under all investigated conditions. AsA synthesis regulation via the clock gene LHY was stable and likely not altered by harvesting stress and/or external light stimuli. After harvesting, SoPRR5 was negatively correlated with SoVTC2. This finding suggested that a reduction in the SoPRR5 expression level might be an alternative way to induce/maintain AsA content during storage. Additionally, the expression of the photoreceptor genes SoPHYA and SoZTL was moderately correlated with that of SoVTC2 during cultivation. Surprisingly, these correlations were not observed during storage even in the presence of light. Instead, SoPHYA expression was correlated with that of another AsA synthesis gene, SoGLDH, under light/dark storage. Moreover, under constant dark storage, SoZTL expression showed a strong correlation with SoVTC2. The considerable variation in the relationship between the expression levels of AsA-related genes and photoreceptor genes during cultivation and storage indicates the contribution of light regulators to maintaining AsA rhythm in spinach. In summary, this study is the first to suggest possible crosslinking of external signals (light/dark), photoreceptor genes, clock genes, and AsA metabolism genes, which are related to changes in the quality of spinach during the pre- and postharvest periods.

本研究では,神奈川県が育成したトマト品種「湘南ポモロンレッド」の日焼けによる品質低下(着色不良)を抑制するため,果実を早期収穫した後の適切な追熟条件を検討するとともに,カロテノイド代謝系の遺伝子発現について解析した.催色期で収穫したトマトを各温度で追熟させた結果,20°C~25°Cの温度帯で追熟を行うことでリコペンが多く蓄積し,またその際に,カロテノイド生合成関連遺伝子の一つPSYおよびプロリコペンをリコペンへと異性化する遺伝子であるCRTISOの発現量も高くなることが明らかとなった.また蛍光灯の照射がカロテノイドの生合成に与える影響としては,照射によりリコペン,β-カロテンの蓄積が高まり,果実の着色も早くなることが明らかとなった.カロテノイド生合成遺伝子の発現も高まっており,蛍光灯の照射がカロテノイド生合成経路を活発化させることが明らかとなった.これらの結果より,「湘南ポモロンレッド」における最適な追熟温度,さらに光照射によるリコペンおよびβ-カロテンの蓄積増大を表現型および遺伝子発現レベルで明らかにした.

Tomatoes develop chilling injury after low-temperature storage, which is often indicated by ion leakage from the Tomatoes develop chilling injury after low-temperature storage, which is often indicated by ion leakage from the tissues caused by cell membrane damage. However, the chilling injury causes a decline in tomato quality, which tissues caused by cell membrane damage. However, the chilling injury causes a decline in tomato quality, which was already serious due to ion leakage. This study assumed that other physiological reactions precede cell was already serious due to ion leakage. This study assumed that other physiological reactions precede cell membrane damage in tomatoes exposed to chilling stress. This hypothesis was investigated by measuring several membrane damage in tomatoes exposed to chilling stress. This hypothesis was investigated by measuring several physical, chemical and physiological parameters of tomatoes. Using samples stored at 2 or 5 degrees & Scy; without chilling physical, chemical and physiological parameters of tomatoes. Using samples stored at 2 or 5 degrees & Scy; without chilling injury-induced cell membrane damage, this study confirmed other abnormal physiological reactions, such as injury-induced cell membrane damage, this study confirmed other abnormal physiological reactions, such as ethylene production, respiration, electrochemical resistance in extracellular fluids, gene expression of heat shock ethylene production, respiration, electrochemical resistance in extracellular fluids, gene expression of heat shock protein, succinic acid content, and others. The obtained information can help clarify the initial response of protein, succinic acid content, and others. The obtained information can help clarify the initial response of chilling injury and is useful to determine the distribution property of tomatoes for avoiding chilling injurychilling injury and is useful to determine the distribution property of tomatoes for avoiding chilling injuryinduced cell membrane damage. induced cell membrane damage.

Broccoli is highly perishable after harvesting. The purpose of this study was to investigate the possibility of estimating the freshness of recently harvested broccoli using visible (Vis) and near-infrared (NIR) spectroscopy. The Vis-NIR spectra of different parts of broccoli were collected as explanatory variables and the cumulative temperature of broccoli under different storage conditions was determined as an indicator of freshness. By combining PLSR analysis and the stepwise selectivity ratio method, an accurate predictive model for the freshness of broccoli florets was constructed using informative wavelengths. Based on strong correlations between the NIR and NMR signals of broccoli florets, seven key amino acids that increased during storage were identified. Among them, isoleucine, valine, asparagine, and phenylalanine were identified as common freshness-marker metabolites shared by different vegetables, such as broccoli and komatsuna. Protein degradation, detected as a change in NIR absorption, can be used to interpret the working mechanism of the calibration model constructed for freshness prediction. Thereby, the interpretable predictive model built based on the informative wavelengths is promising for reliable and accurate estimation of broccoli freshness in the supply chain.

In this study, the time–temperature tolerance theory was adopted to determine the critical duration for postharvest banana exposure in the plantation without the emergence of physiological disorders and quality loss. Bananas were exposed to various high temperatures (35 °C–51 °C) for durations ranging from 5 min to 12 h. Subsequently, they were treated with 200 ppm ethylene for 24 h and stored at 20 °C for ripening. The ripening color index was monitored during storage, and when it reached 125, quality attributes in treatments were compared, including L* value, sugar content, oxalic acid content, firmness, and pulp-to-peel ratio. Bananas exposed to temperatures ≤40 °C ripened normally, whereas those exposed to temperatures of ≥45 °C exhibited reduced sugar content depending on exposure duration. A linear fractional model effectively expressed the relationship between the flesh temperature and the critical time limit for normal ripening. Introducing a new indicator, the risk ratio (RR), allowed the assessment of abnormal ripening probability, which was assumed to vary according to zero-order kinetics. The temperature-dependent rate constant of RR adhered strongly to the Arrhenius equation, enabling RR prediction under specific temperature conditions. In validation testing, bananas with an RR of 0.9 exhibited sugar content equivalent to the control, whereas those with an RR of 1.1 showed significantly lower sugar content. Overall, this study demonstrates a novel approach for estimating the critical safe duration bananas can remain in the field after harvest, thereby mitigating postharvest losses.

The circadian system plays an essential role in plant cells, and numerous physiological events are generally modulated by circadian clock genes. To further improve postharvest handling of fresh produce, it is vital to understanding the behavior of clock gene expression and its underlying interactions with changes in quality. In this study, the effect of temperature and controlled atmosphere storage on the expression of clock genes (GmLCL1, GmPRR7, GmGI, GmTOC1, and GmLUX), postharvest quality characteristics and their related genes in soybean sprouts were investigated. By fitting the obtained gene expression level using the qPCR method with the cosine curve equation, it was successfully found that the circadian rhythm existed under constant dark storage conditions of soybean sprouts. A significant rhythm in clock gene expression was observed in control soybean sprouts. In contrast, low temperature storage diminished the cyclic expression of GmLCL1, GmPRR7, and GmTOC1, which also affected GmGI and GmLUX expression. Additionally, high CO2 concentrations during storage disturbed the circadian clock by affecting the phase and amplitude of each gene; for low O2 concentrations, it was only affected by amplitude. Interestingly, low temperature, low O2, and high CO2 maintained postharvest quality, including reduced respiration, weight loss and browning incidence. The expression behaviors of postharvest quality attribute-related genes (GmFUM1, GmCS, Gm2-OGDH, GmPPO1, GmPAL) were also influenced by the storage treatments. Overall, the findings first suggest a possible link between clock disruption and postharvest quality maintenance of soybean sprouts.

Occurrence of internal browning in sweet potato tuber has recently been confirmed, and its chemical and bacterial characteristics have been reported. However, the structural characteristics of such tissues are unknown. We investigated the tissue structural characteristics inside a browning sweet potato through magnetic resonance imaging (MRI) and bio-electrochemical impedance spectroscopy (BIS) and the relationship was discussed. The high-resolution proton density-weighted (PDW) and proton spin–spin relaxation time (T2)-weighted (T2W) images of cutting out samples obtained from micro-imaging revealed changes in the physical structure surrounding the browning tissues. The T2 distribution maps of the same browning samples assumed the changes in the water distribution and water mobility, which generally changes under the influence of solutes, such as metabolites, starch, protein, and metal ions. BIS further confirmed the variation in the distribution of electrolytes in the tissues. MRI may provide a non-destructive assessment of the internal browning of whole sweet potatoes.

Chilling injury in cucumber is commonly thought to begin with cell membrane damage caused by reactive ox-ygen species, which results in ion leakage from the tissue. However, additional short-term storage at ambient temperature after cold storage can accelerate the appearance of damage, and the different types of vegetables exhibit distinct symptoms. We hypothesized that cell membrane damage is a secondary reaction, and that pre-ceding responses in the tissue lead to irreversible changes. To explore these responses in cucumber tissue during cold storage, we employed several techniques, including ion leakage measurements, bio-electrochemical impedance spectroscopy, X-ray computed tomography, nuclear magnetic resonance-based metabolite profiling, and transcriptome analysis. Our time-course comparison of different storage conditions (2 degrees C, 5 degrees C, 10 degrees C, and 15 degrees C for 0-14 d) indicated that several responses preceded detectable ion leakage-associated cell membrane damage. Specifically, the cold-stored samples exhibited abnormal electrolyte distribution and marked changes in metabolite levels and gene expression related to the tricarboxylic acid (TCA) cycle, which is critical for generating energy for homeostasis. Moreover, samples stored at 2 degrees C followed by 15 degrees C showed earlier initiation of tissue responses in metabolite and gene expression profiles, suggesting the occurrence of irreversible changes, possibly in the TCA cycle. These findings suggest that the critical response to chilling injury may occur prior to cell membrane damage, likely due to metabolic imbalances in the TCA cycle.

Lipids are biochemical compounds that are substantially present in coffee beans. However, lipids in coffee have not been comprehensively studied thus far and have not been used to differentiate its geographical origin. This study aimed to investigate the applicability of lipid profiling for use in coffee origin authentication. In this study, Indonesian superior coffee originating from six major producing regions was used. Lipid extraction from roasted coffee was subjected to a high-performance liquid chromatography coupled with triple-quadrupole mass spectrometry (LC–MS/MS). The obtained data were analyzed using the multivariate approach, including partial least squares discriminant analysis (PLS-DA), principal component analysis, and clustering analysis. The LC–MS/MS analysis tentatively identified 85 lipid species from five global lipid classes, such as neutral lipids, sphingolipids, sterol, glycerophospholipids, and glyceroglycolipids. The PLS-DA model exhibited an accuracy of 90

The quantitative freshness assessment method for vegetables is desired to upgrade the quality management system in agricultural distribution chain. Since lipid has broad diversity in species and plays an important role in the biological metabolism of plants, there is a possibility that lipid profile indicates the freshness of harvested vegetables. The aims of this study were to clarify the lipidomic alteration of stored cabbage and identify lipid molecules indicative of freshness. Cabbage leaves stored at 5 °C, 10 °C, and 20 °C were sampled periodically for lipidomic analysis by liquid chromatography-tandem mass spectrometry. The cumulative respiratory CO2 production was determined using a flow-through method via gas chromatography. A total of 74 lipid species had a significant correlation with cumulative CO2 production. Hierarchical cluster analysis (HCA) clustered them into three main groups. A partial least squares regression (PLSR) model established the relationship between the abundance of lipid species and the cumulative CO2 production. Four lipid molecules were selected as potential freshness markers. The PLSR model with the selected markers had a better performance in predicting the cumulative CO2 production than that by ascorbic acid which is conventionally used as a quality indicator of fresh produce. Our results show that lipidomic profiling could be viable for assessing the freshness of whole cabbage.

Nutritional benefits and organoleptic characteristics, including visual, textural, taste, and flavor, are the critical characteristics of economically important fruit. Ripening is a crucial phenomenon in the formation of these quality characteristics in fruits. Therefore, controlling the ripening phenomenon is extremely important not only to maximize the benefits of the fruit but also to avoid food losses caused by over-ripening. Tomato is an important model plant, especially for research on fruit ripening. The metachronous model of tomato ripening is presented in this report. This model predicts the postharvest ripening time of tomato fruit in terms of red color development based on the storage period. A modified sigmoid-type function model was used to develop the prediction model. The observations and analyses were conducted at different storage temperatures and in different tomato cultivars. The result exhibits that the integration of the proposed model and time lag was successfully showing the postharvest ripening time history of tomato fruit at the full range ripening process, from onset to fully ripe. This study provides critical information on postharvest quality control research and supply chain development in eliminating food loss and waste, which leads to the realization of sustainable development goals.

To prevent insect contamination in food supply chains, an understanding of the circumstances and timing of insect invasion is important. Fragmented insects are often found in food products, and mechanical stress such as drop shock during transportation and/or handling may contribute to such fragmentation. In this study, we used two stored grain pest species, Tribolium castaneum and Sitophilus zeamais, to investigate the effects of drop shock and the state of the insect (living, or dead for 1 day or 1 month) on the number and size of insect fragments. A cardboard box containing an adult insect placed between two aluminum plates was dropped from heights of 0.2-0.8 m. The results revealed that the number of fragments of dead insects of both groups was larger than that of living insects. Both species showed similar trends in the number of fragments, although the two species had different fragilities at each drop height. The number of fragments increased with the drop height for both groups of dead insects, but it was not associated with the drop height for living insects. The trends of fragmentation suggested that an insect with a large number of fragments was subjected to severe shock after death, whereas one with a small number of fragments was subjected to light shock after death or to any degree of drop shock while alive. We concluded that the difference in fragmentation can provide useful information about the circumstances and timing of insect contamination in food supply chains.

In this study, the specific changes in the electrical impedance properties of sweet potato tissues under low-temperature storage are reported. The tissue status was monitored by using an electrical indicator, LTO (which refers to the distance from the origin of the coordinate at the top of the circular arc of the corresponding Cole-Cole plot), and its variation was investigated at storage temperatures of 0, 5, and 13 degrees C for 20 d. Our results show that the LTO values increased gradually during storage for up to10 d. Moreover, the change kinetics constant increased linearly with decrease in the storage temperature. Furthermore, by 20 d, the LTO values of samples stored at 0 degrees C had significantly decreased. We speculate that these changes are influenced by changes in the sugar concentration or by the occurrence of chilling injury. These findings indicate that the LTO has applicability as a tool to rapidly monitor changes in the status of sweet potato tissues during low temperature storage. (C) 2021 IAgrE. Published by Elsevier Ltd. All rights reserved.

Peach fruits are very susceptible to mechanical stress and are therefore typically harvested before they are ripe and softened. However, there is limited information available on the damage characteristics of fruits varying in firmness. In this study, we conducted a shock test (29.4-1,802.8 m・s-2) of peach fruit (cv. 'Kanoiwa-Hakutou') that varied in firmness across four ranges and identified the damage characteristics. The results showed that the effect of shock on damage to peach fruits can be reflected as S-N curves, in which the function of relationships between shock acceleration and the number of cycles to lose the commercial value. Based on these findings, we developed a regression models for the prediction of the S-N curve parameters (α, β) according to the fruit firmness (R2=0.74 and 0.90, respectively). The determination of S-N curve parameters of fresh produce that change their damage characteristics at postharvest period could be used to select an appropriate cushioning material or transport destination, which can reduce loss induced by shock damage during the distribution phase.

To elucidate a mechanism for enhancing mung bean seedlings' growth under microgravity conditions, we measured growth, gene expression, and enzyme activity under clinorotation (20 rpm), and compared data obtained to those grown under normal gravity conditions (control). An increase in fresh weight, water content, and lengths were observed in the clinostat seedlings, compared to those of the control seedlings. Real-time PCR showed that aquaporin expression and the amylase gene were upregulated under clinorotation. Additionally, seedlings under clinorotation exhibited a significantly higher amylase activity. Near-infrared image showed that there was no restriction of water evaporation from the seedlings under clinorotation. Therefore, these results indicate that simulated microgravity could induce water uptake, resulting in enhanced amylase activity and seedling growth. Upregulated aquaporin expression could be the first trigger for enhanced growth under clinorotation. We speculated that the seedlings under clinorotation do not use energy against gravitational force and consumed surplus energy for enhanced growth.

To develop a regression model for the prediction of the physical properties, applicable to peach fruits stored at different temperatures, the respiration rate (CO2 output rate) and five physical parameters of peach fruits (cv. Kanoiwa-Hakutou) were investigated in the context of storage at 0, 5, 10, 15, 25, and 35℃. The firmness index of the peach fruits was measured using a hand-held firmness tester, whereas the maximum load, spring constant at small and large deformations, and flesh firmness were measured using a universal firmness tester. The changes in the five physical parameters over time showed similar tendencies, and the physical parameters correlated well with cumulative respiration. Consequently, we developed a mathematical model for the prediction of the physical parameters of individual samples based on their cumulative respiration, which followed a sigmoid-type function. The data obtained for these five physical parameters using the model showed a high correlation coefficient (R2=0.819-0.921), and the spring constant at a small deformation showed the highest value among all parameters. These results indicate that developing a model using cumulative respiration as a variable is feasible and allows the prediction of changes in the firmness characteristics of peach fruits during the postharvest period.

This study shows several genes in sweet potatoes, whose expression level changed during low-temperature storage. In addition, the relationship between their expression and occurrence of chilling injury was investigated. The expression levels of phenylalanine ammonia-lyase A (PALA), ACC oxidase, regulatory protein NPR1, 70 kDa heat shock protein, and α-amylase were increased upon storage at 5-10 ℃; however those of β-amylase (BAM) and starch synthase were decreased. The effects of continuous changes in storage temperatures on the expression of PALA and BAM were investigated. The changes in their expression levels during storage at 5 ℃ within 10 days could be recovered by storage at 20 ℃ for 5 days; however, at 5 ℃ for more than 15 days, the recovery phenomenon was not observed. PALA expression level increased at below 10 ℃, but was absent at over 13 ℃. Heat shock treatment at 40 ℃ for 2 days did not affect the expression levels of these genes. These findings indicate the irreversible physiological changes in sweet potatoes according to by low-temperature storage periods and can be used as expression makers of chilling injury.