Comparative Transcriptomic Analysis of Two Tomato Cultivars with Different Shelf-Life Traits

Tomato(Solanum lycopersicum)is a perishable fruit because of its fast water loss and susceptibility to pathogens in the post-harvest stage,which leads to huge economic losses every year.In this study,firstly from 19 tomato cultivars,we screened out two cultivars,Riogrand and SalarF1,having long and short shelf-life spans,respectively.Secondly,shelf-life analysis was carried out for both cultivars at room temperature.Results exhibited that Riogrand showed higher firmness and less weight loss than SalarF1.The ethylene production was higher in SalarF1,compared with Riogrand during post-harvest storages.We performed transcriptomic analysis of both cultivars in different storage stages.We discovered 2913,2188,and 11,119 differentially expressed genes(DEGs)for three post-harvest stages(0,20,and 40 Days Post-Harvest(DPH)),respectively.These genes are enriched in ethylene biosynthesis and response,as well as cell wall-related genes.Ethylene response factor(ERF)ERF2 and ERF4 were highly expressed in SalarF1 with a short shelf life in 40 DPH,and the ethylene biosynthetic genes ACO1,ACO4,ACS6,and ACS2 were significantly upregulated in SalarF1.Regarding cell wall loosening and cell wall-related genes XTH3,XTH7,XTH23,1,3;1,4-β-D-Gluc-like,pGlcT1,Cellulase,PGH1,PL5,PL-like 1,PL-like 2 exhibited the highest levels of significance,being notably upregulated in the last stage of SalarF1.The quantitative real-time polymerase chain reaction(qRT-PCR)analysis validated these gene expressions,which is in line with the transcriptome analysis.The findings suggested that the extension of tomato fruit shelf life is mostly dependent on ethylene biosynthesis,signaling pathway genes,cell wall loosening,and cell wall-associated genes.

Deep Learning-Based Classification of Rotten Fruits and Identification of Shelf Life

The freshness of fruits is considered to be one of the essential characteristics for consumers in determining their quality,flavor and nutritional value.The primary need for identifying rotten fruits is to ensure that only fresh and high-quality fruits are sold to consumers.The impact of rotten fruits can foster harmful bacteria,molds and other microorganisms that can cause food poisoning and other illnesses to the consumers.The overall purpose of the study is to classify rotten fruits,which can affect the taste,texture,and appearance of other fresh fruits,thereby reducing their shelf life.The agriculture and food industries are increasingly adopting computer vision technology to detect rotten fruits and forecast their shelf life.Hence,this research work mainly focuses on the Convolutional Neural Network’s(CNN)deep learning model,which helps in the classification of rotten fruits.The proposed methodology involves real-time analysis of a dataset of various types of fruits,including apples,bananas,oranges,papayas and guavas.Similarly,machine learningmodels such as GaussianNaïve Bayes(GNB)and random forest are used to predict the fruit’s shelf life.The results obtained from the various pre-trained models for rotten fruit detection are analysed based on an accuracy score to determine the best model.In comparison to other pre-trained models,the visual geometry group16(VGG16)obtained a higher accuracy score of 95%.Likewise,the random forest model delivers a better accuracy score of 88% when compared with GNB in forecasting the fruit’s shelf life.By developing an accurate classification model,only fresh and safe fruits reach consumers,reducing the risks associated with contaminated produce.Thereby,the proposed approach will have a significant impact on the food industry for efficient fruit distribution and also benefit customers to purchase fresh fruits.

Co-Treatment of EFF and 1-MCP for Enhancing the Shelf-Life and Aroma Volatile Compounds of Oriental Sweet Melons(Cucumis melo var.makuwa Makino)

Compared to other melon types, oriental sweet melon （Cucumis melo var. makuwa Makino） is quite a different species with a shorter shelf-life due to its typical climacteric behavior and thin pericarp. The purpose of this experiment is to explore the effects of co- treatment of enhanced freshness formulation （EFF） and 1-methylcyclopropene （1-MCP） on physiological changes and the content of aroma volatile compounds introduced by them of two oriental sweet melon cultivars （Yumeiren and Tianbao） during storage. The melons were stored in incubators with temperature of 15~C and a relative humidity of 85% for 24 d during which fruit quality and related physiological index were measured. Compared to the control, both treatments delayed fruit weight loss rate and kept the fruit firmness, water content and soluble solids content. Ascorbate peroxidase （APX） and phenylalanine ammonia lyase （PAL） activities showed fluctuations in treated melons, while lipoxygenase （LOX） activity （P〈0.01） and malondialdehyde （MDA） content （P〈0.05） decreased compared to control. During the early stage of storage, alcohols and aldehydes were the main volatile compounds, and esters gradually increased during storage. Of all the esters, acetic esters were the main components, followed by oxalic acid esters and other esters. The total content of aroma volatile compounds, esters, alcohols and aldehydes of co-treated melons were all higher than those of 1-MCP treated and control melons. In addition, the aroma volatile peak of co-treated melons occurred later than that of 1-MCP treated and control melons. In summary, co-treatment of EFF and 1-MCP was more beneficial than 1-MCP treatment to delay ripening and senescence, maintain fruit quality, enhance shelf-life and improve levels of aroma volatile compounds.

Chemical stability, thermal behavior, and shelf life assessment of extruded modified double-base propellants

Double base propellant suffers from lack of chemical stability; this could result in self ignition during storing. Modified double base(MDB) propellant based on stoichiometric binary mixture of oxidizermetal fuel(Ammonium perchlorate/Aluminum), and energetic nitramines(HMX) offered enhanced thrust as well as combustion characteristics. This study is devoted to evaluate the impact of such energetic additives on thermal behavior, chemical stability, and shelf life. Extruded MDB formulations were manufactured by extrusion process. Artificial aging at 80℃ for 28 days was conducted. Shelf life assessment was performed using Van't Hoff's equation. Quantification of evolved NOxgases with aging time was performed using quantitative stability tests. MDB formulation based on HMX demonstrated extended service life of 16 years compared with(AP/Al)-MDB which demonstrated 9 years. This finding was ascribed to the reactivity of AP with nitroglycerin with the formation of perchloric acid. Thermal behavior of aged MDB, exhibited an increase in heat released with time; this was ascribed to the autocatalytic thermal degradation during artificial aging. The increase in released heat by 31% was found to be equivalent to evolved NOx gases of 6.2 cm^3/5 g and 2.5 cm^3/1 g for Bergmann-Junk test, and Vacuum stability test respectively. This manuscript shaded the light on a novel approach to quantify evolved NOx gases to heat released with aging time. MDB based on HMX offered balanced ballistic performance,chemical stability, and service life.

Novel aspects for thermal stability studies and shelf life assessment of modified double-base propellants

Modified DB propellants, based on energetic nitramine(RDX) were manufactured by solventless extrusion process. Thermal stability and shelf life assessment of modified DB propellant were investigated. Shelf life assessment was evaluated using Van’t Hoff’s formula and artificial aging at 70℃ up to120 days. Quantification of total heat released and heat flow with aging time was conducted using differential scanning calorimetry(DSC) and thermal activity monitoring(TAMIII) respectively. Modified DB formulation based on 20 wt % RDX demonstrated enhanced thermal stability in terms of controlled heat flow, and slow decomposition reactions at elevated temperature. This formulation demonstrated extended service life up to 56 years compared with reference formulation. These novel finding was ascribed to the high thermal stability of RDX and its compatibility with DB constituents. This manuscript shaded the light on novel and effective approach for thermal stability via monitoring thermal activity with aging.

Effect of Pre-Harvest Application of Gibberellic Acid on Fruit Quality and Shelf Life of Mandarin (Citrus reticulata Blanco)

Mandarin (Citrus reticulata Blanco) is a promising fruit crop gaining popularity for its human nutrition and economic importance in Nepal. The qualitative losses during pre-harvest stage hinder the productivity and subsequently shorten the on-tree storability. An experiment was conducted to assess the effect of gibberellic acid on quality and shelf life of the mandarin fruit. GA3 at 10, 20, and 30 ppm as against of control were evaluated. Observations on fruit weight (g), fruit firmness (kg/cm2), rind colour (1 - 5 index), juice recovery (%), TSS/acid ratio, PLW (%), decay loss (%), and ascorbic acid (mg/100 ml) were recorded at three harvesting dates i.e. 20 Nov, 5 Dec, and 20 Dec and storage condition. It has been revealed that the fruits treated with GA3 at 20 ppm retained higher fruit weight (128.6 g), more firmness (3.54 kg/cm2), better juice recovery (57.75%), and greater TSS/acid ratio (21.24) at the end of study (20 December). The PLW was found less with GA3 at 30 ppm in both ambient (5.17%) and cellar (6.69%) condition as against untreated fruits (9.52% and 11.76%). Similarly, the decay loss was minimum in the fruits treated with GA3 at 30 ppm both with ambient (1.02%) and cellar condition (8.21%) as against control with ambient (5.54%) and cellar (21.58%).

Exogenous melatonin improves the chilling tolerance and preharvest fruit shelf life in eggplant by affecting ROS-and senescence-related processes

Low temperature is the most common abiotic stress factors during the eggplant cultivation in solar greenhouses.Melatonin plays important roles in plant resistance to low temperature.However,the role of melatonin in regulating chilling tolerance and extending the preharvest shelf life of eggplant fruits is still unknown.In this study,we investigated the effects of exogenous melatonin on eggplant plants and fruits in response to low temperature.Under simulated low-temperature conditions,exogenous melatonin significantly relieved the chilling symptoms of seedlings by reducing reactive oxygen species (ROS) and malondialdehyde (MDA) levels and relative leakage rates.These reductions were caused by higher superoxide dismutase (SOD) and catalase (CAT) activities and increased endogenous polyamine and melatonin levels compared with those in untreated seedlings.Notably,the expression levels of SOD,CAT1/2,and polyamine synthesis genes (ADC and ODC) were also increased by 100μmol·L~(-1)melatonin,as well as those of genes involved in melatonin synthesis (TDC,T5H,SNAT,ASMT,and COMT) and cold regulation (COR1,CBFa/b,and ZAT2/6/12).To further investigate the effects of melatonin on eggplant leaves and fruits under natural low temperature conditions,100μmol·L~(-1)melatonin was sprayed on the functional leaves at three days before commodity maturation.Melatonin significantly alleviated chilling injury in the leaves and pericarp and extended the preharvest shelf life of the fruit by increasing the expression of COR1,CBF,ZAT2/6/12,and API5 and decreasing the expression of senescence-related genes (NCED1/2 and SAG12).Therefore,100μmol·L~(-1)melatonin improved chilling tolerance and fruit shelf life by upregulating ZAT2/6/12 to affect ROS-and senescence-related processes,which provides a reference for alleviating cold stress and extending the preharvest fruit shelf life in eggplant.

Novel approach to quantify the chemical stability and shelf life of modified double-base propellants

Double-base(DB) propellant is vulnerable to auto-catalytic decomposition reactions during storing with the evolution of nitrogen oxides. Modified DB propellant based on energetic nitramines(RDX) can offer enhanced thrust and action time. This study is devoted to evaluate the impact of RDX on chemical stability and shelf life of DB propellant. Extruded modified DB propellant based on RDX was manufactured by solventless extrusion process. Shelf life assessment was performed using an artificial aging at70 ℃ up to 120 days and employing Van't Hoffs formula. Quantification of evolved NOx gases and stabilizer depletion with aging time was conducted using Bergmann-Junk test and HPLC respectively.Modified DB formulation based on RDX 20 wt % demonstrated enhanced chemical stability and extended service life up to 46 years compared with reference formulation. This finding was ascribed to the high chemical and thermal stability of RDX as well as its compatibility with DB constituents; no side chemical reactions could take place during storing. This manuscript shaded the light on RDX as effective energetic constituent that offered DB propellants with enhanced performance, good chemical stability, and extended service life.

Effect of Packaging Conditions on Shelf-Life of Mortadella Made with Citrus Fibre Washing Water and Thyme or Rosemary Essential Oil

The “elimination” of chemical additives used in a wide variety of foods is demanded, while “natural” additives are seen as a benefit for both quality and safety. Researchers are looking for new sources of ingredients and/or additives. The aim of this work was to study the effect of 1) the addition of 5.00% citrus fibre washing water (CFWW) and 0.02% rosemary essential oil (REO) or 0.02 % thyme essential oil (TEO) and 2) storage conditions on the chemical, microbe- ological and sensorial properties of mortadellas, a bologna-type sausage. CFWW + REO or CFWW + TEO samples stored in vacuum packaging showed the lowest TBA values. The resulting products were packed either in vacuum, modified atmosphere or air pouches and stored for 24 days. Lipid oxidation was assessed by the TBA method, while a quantitative descriptive analysis was carried out for sensory evaluation. Microbiological counts were also determined. CFWW + REO samples stored in vacuum packaging showed the lowest counts of aerobic and lactic acid bacteria. The sensory evaluation provided similar scores for CFWW + REO and CFWW + TEO samples. The lowest scores were obtained for control mortadella stored in air packaging. The addition of citrus fibre washing water and spice essential oils is a technologically viable alternative in emulsified meat products, since they improve customer acceptance and have desirable effects as regards oxidative stability and reduced microbial growth, which contributes to prolonging their shelf-life.

Effects of Chitosan on the Shelf Life of Harbin Red-sausage

Chitosan and Chitin can inhibit the growth of bacteria. The effect of different concentrations of chitosan solutions on the shelf life of Harbin Red-sausage was studied in this paper. Dipping the Red-sausage with chitosan could extend the shelf life significantly. The optimal composition of coating solution was 3% chitosan solution, whose deacetylated rate was 94%, which was dissolved in 2% acetic acid solution. The CFUs of the sausages with the chitosan deacetylated rate 94% treatment were significantly lower than control at the whole storage （P 〈0.05）.

Prolonging the Shelf Life of Ready-to-Serve Pizza through Modified Atmosphere Packaging: Effect on Textural and Sensory Quality

The effects of different modified atmospheres (air: atm1;100% CO2: atm2;100% N2: atm3;50% CO2/50% N2: atm4) on the textural and sensory characteristics of the ready-to-serve pizza at 7℃ ± 1℃ were investigated. The values of hardness, gumminess and chewiness were found to be increased during the storage period while cohesiveness and springiness exhibited a decreasing trend. Overall, the 100% CO2 product yielded the best textural and sensorial characteristics followed by 50%CO2/50% N2 and 100% N2 when compared to conventional packed pizza at 7℃ ± 1℃. Carbon dioxide caused microbial inhibition as well. The shelf life of ready-to-serve pizza significantly increased upto 45 days (a 300% increase) for the samples packaged under 100% CO2 (atm2), 50% CO2/50% N2 (atm4) and 100% N2 (atm3), compared to conventional air pack (15 days).

Effect of Post-Harvest Handling and Ripening Methods on Quality and Shelf-Life of Banana

Banana (Musa spp.) is a highly perishable fruit that requires special handling. In Eritrea, post-harvest handling practices are characterized to be poor and as a result, poor fruit quality and high post-harvest loss are common. Thus, the purpose of this study was to evaluate the effect of different post-harvest handling and ripening methods on quality and shelf-life of banana. A Complete Randomized Design (CRD) was used for evaluating a combination of two levels of post-harvest handling and four ripening methods in a factorial combination conducted in the laboratory of Horticulture at Hamelmalo Agricultural College. Peel colour change, physiological weight loss, pulp to peel ratio, total soluble solids (TSS), pulp pH, ripening period and shelf life were parameters studied. The results showed fruits treated with ripened tomato showed improved characteristics in all parameters compared to those treated with smoke from kerosene burning or mixed with moringa leaf. Similarly, fruits brought directly from the farm were better than those collected from the ripening room after passing the conventional post-harvest handling. Based on the results of this study, it can be concluded that ripening of banana with the help of tomato improves fruit quality and shelf life. Thus, it can be a safe and better alternative to smoking from kerosene burning. While moringa leaf has no potential as an alternative.

A kinetic model for predicting shelf-life of fresh extruded rice-shaped kernels(FER)

Fresh extruded rice-shaped kernels(FER) are remoulded rice products from cereals or seed flours, which have the advantages of safety, nutrition, health and time saving. However, the finished products are easy to react with oxygen, so it is necessary to develop a fast, simple and reliable approach to monitor and predict the shelf-life of FER. A comprehensive mathematical model of FER shelf-life prediction was developed using a dynamic modelling approach based on real supply chain conditions. This predictive model was developed to determine four key indexes including acid value, iodine blue value, water uptake ratio and peroxide value. The results showed that when the peroxide value was 1.6849, the FER lost its edible value, nutritional value and commodity value. Moreover, the acid value and peroxide value of FER were used to establish a first-order kinetic model, and the iodine blue value of FER was suited for a zero-order kinetic model. The validation experiment of predicted and measured shelf life showed that the relative error was 3.12%, which was less than 5%. Therefore, this kinetic model could be used to predict the shelf-life of FER quickly and conveniently. The kinetic-based shelf-life prediction model proposed in this study is rapid and practical, providing theoretical basis and guidance for the establishment of quality monitoring and quality evaluation systems of FER during the production, storage, transport and marketing.

Shelf-Life Extension of Tomato （Lycopersicum esculentum） and Pepper （Capsicum annuum） Using Aqueous Extracts of Some Ethnomedicinal Plants

This research aimed at the use of natural products to extend the shelf life of perishable vegetables. Studies were conducted on the preservative effects of four plant extracts--Xylopia aethiopica, Piper nigrum, Tetrapleura tetraptera and Carica papaya seeds on tomato and pepper. Tomato and pepper were dipped into four different concentrations of aqueous extracts of the four plants as well as water serving as control. The result of the study showed that aqueous extract of all plants extended the shelf life of tomato and pepper with increasing concentration of the extracts, except for Carica papaya seeds which produced significant elongation of 12.0 ±0.6 d and 14.0 ± 0.7 d on tomato and pepper, respectively, at the least concentration of 0.25 mg/mL. The results showed that these ethnomedicinal plants can serve as good and potent sources of natural preservatives which can be used to substitute existing synthetics used in the food industry.

A Time Dependent Inventory Model for Exponential Demand Rate with Constant Production Where Shelf-Life of the Product Is Finite

In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considering those products which have finite shelf-life. The model also considers the small amount of decay. Without having any sort of backlogs, production starts. Reaching at the desired level of inventories, it stops production. After that due to demands along with the deterioration of the items it initiates its depletion and after certain periods the inventory gets zero. The decay of the products is level dependent. The objective of this paper is to find out the optimum inventory cost and optimum time cycle. The model has also been justified with proving the convex property and by giving a numerical example.

Use of Bitter Leaf(Vernonia amygdalina)Extract and Pasteurization Aim at Improving the Sensory Quality and Shelf-life of Mpedli,a Traditional Opaque Sorghum White Beer from Northern Cameroon

The purpose of this study was to evaluate the sensory property and shelf life of the processed mpedli beer using aqueous leaves extract of Vernonia amygdalina(VA)and heat treatment.The white sorghum beer was made at the laboratory scale using home-made procedure(Control).Following filtration,the beer was blended with an aqueous leaf extract(1/10,v/v)of VA(BUB).Pasteurization(60°C/30 min)was performed on a portion of the VA blended sample(BPB).The sensory parameters and shelf life of the three samples were evaluated at room temperature during a month storage.The sensory characteristics of blended and non-supplemented mpedli beer differed significantly(p<0.05).During storage,the colour,bitterness,aroma,odour,viscosity,texture,and overall acceptability of the processed samples were improved.Bitterness(r=0.898;p<0.01)and odour(r=0.930;p<0.01)were both highly correlated with the acceptance of the processed beer.The non-supplemented samples had the highest sensory scores 48 hours after preparation,while the relevant sensory ratings in processed BUB and BPB samples were recorded from the 12th to the 21st and 27th day of storage,respectively.The findings suggest that combining pasteurization with addition of aqueous leaf extract of VA may help small-scale brewers for improving the sensory quality and extending the shelf life of mpedli.According to the findings,the use of bitter leaf could be proposed as an alternative hop in the local brewing industry and may increase incomes of producers of local sorghum beer.

Optimization of Antibacterial Conditions in Freshcut Grass Carp Belly and Comparison of Shelf Life

With fresh-cut grass carp belly as the test material, the antibacterial con- ditions of a disinfection agent sodium hypochlorite were optimized. In addition, the shelf lives of various grass carp products were compared after disinfection, so as to provide certain basis for the processing of fresh-cut grass carp products. The re- sults showed that the optimal disinfection conditions of sodium hypochlorite were as follows： concentration 300 mg/L, soak time 5 min and solid-liquid ratio 1 g ： 5 ml. Under the optimal disinfection conditions, the inhibition rates of total bacteria and Pseudomonas reached 83% and 81%, respectively. The shelf life of refrigerated fresh-cut grass carp belly disinfected by sodium hypochlorite and packed in bag filled with gases could be extended as long as 11 d, which was increased by 5 d （83%） compared with that in the control group. The disinfection by sodium hypochlorite could significantly reduce the initial bacterial colony number and improve the sensory quality of fresh-cut grass carp belly, as well as extend the shelf life of refrigerated and modified gas-packed grass carp belly.

Study on Preservative Formula and Shelf Life of Cantonese Style Moon Cakes

To ensure the safety of consumers, prolong the shelf life of moon cake and reduce the cost of manufacturing and marketing enterprises, the optimization of preservative formula and the shelf life of cantonese style moon cake were studied. Through single and compound formula preservative test, the results showed that potassium sorbate and sodium dehydroacetate could inhibit the microorganisms in the moon cake, but the inhibitory effect of sodium dehydroacetate was stronger than that of potassium sorbate; and the combination of potassium sorbate and sodium dehydroacetate had a synergistic effect, and the best formula is ＇potassium sorbate 0.44 g/kg mixed with sodium dehydroacetate 0.38 g/kg. A batch of moon cake was prepared with the best preservative formula, then the total number of colonies, molds and coliform group in the samples were detected by random sampling at irregular intervals. The total number of molds exceeded the limit on the 187^th d, and it indicated that the shelf life of the product was 187 d. Compared with the conventional 15-day shelf life, this research greatly prolongs the sheff life of cantonese style moon cake, and cut down the cost of moon cake enterprises. It is worthy of popularization and application.

High Pressure Treatment Changes Spoilage Characteristics and Shelf Life of Pacific Oysters(Crassostrea gigas)During Refrigerated Storage

The effects of high pressure(HP) treatment on spoilage characteristic and shelf life extension of Pacific oysters(Crassostrea gigas) during refrigerated storage were studied.Results showed that HP treatment of 275 MPa for 3 min or 300 MPa for 2 min could achieve 100% full release of oyster adductor muscle,pressures higher than 350 MPa caused excessive release as the shells of oysters were broken,thus use of higher pressures should be cautious in oyster processing industry because of its adverse impact on the appearance of shells.HP treatment(300 MPa,2 min) was proper for the shucking of Pacific oyster(Crassostrea gigas) in China.This treatment caused no organoleptic disadvantage.Moreover,HP treatment resulted in obvious differences in biochemical spoilage indicators(p H,TVB-N and TBARS) changes and volatile compounds profile determined by electronic nose during storage.HP treatment(300 MPa,2 min) also led to a reduction of aerobic bacterial count(APC) by 1.27 log cycles.Furthermore,the APC values of oysters treated by HP were always lower than those of the control samples during storage.Based on the organoleptic,biochemical and microbiological indicators,shelf life of 6-8 d for control and 12 d for HP-treated oysters could be expected.HP treatment showed great potential in oyster processing and preservation.

基于CNN-GRU-AE的蓝莓货架期预测模型研究

为探究贮藏于不同温度条件下蓝莓的品质变化及货架期,以‘自由’蓝莓为研究对象,测定其在0、4、25℃条件下的颜色参数、质量损失率、腐败率、质地参数等共计21个品质指标。通过5种具有自带特征选择功能的机器学习算法,筛选出7个影响货架期的关键特征作为模型的输入变量,构建基于注意力(attention,AE)机制的卷积神经网络(convolutional neural network,CNN)和门控循环单元(gated recurrent unit,GRU)的蓝莓货架期预测模型。结果表明,与原始GRU相比,CNN-GRU-AE模型的平均绝对误差、均方误差和平均绝对百分比误差分别降低了75.83%、91.46%、61.58%,决定系数增加了2.25%。说明添加注意力机制并与CNN结合后的GRU模型显著提高了货架期的预测精度。本研究可为蓝莓在不同贮藏温度条件下的货架期制定提供理论支持,并为剩余货架期的预测提供技术帮助。