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.

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.

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%).

Changes in Chilled Chicken Quality and Correlation Analysis during Different Shelf Life

[Objective] The paper was to study the change rule and correlation analysis of quality indexes of chilled chicken within 7 d shelf life.[Method] Six pieces of fresh breast muscle were packaged in polyethylene（PE） food storage bags,labeled,and refrigerated at 4 ℃.The p H,water loss rate,tenderness,color value and inosinic acid content of chicken were measured at different time points of preservation（cold storage for 0,1,2,3,6,7 d）.[Result] With the prolongation of shelf life,the p H of chilled chicken first increased then tended to be stable;the water loss rate first increased then stabilized;the shear force first decreased then increased.There was little difference in brightness value（L＊） of chilled chicken dur-ing different shelf life（P〉0.05）.The red degree value（a＊） decreased with the prolongation of shelf life;the yellow degree value（b＊） increased with the extension of shelf life.The inosinic acid content decreased with the prolongation of shelf life.The p H of chilled chicken in different shelf life had significant positive correlation with water loss rate（P〈0.05） and extremely significant negative correlation with shear force（P〈0.01）.[Conclusion]The shelf life of 7 d has impact on meat color and inosinic acid of chilled chicken.Cold fresh preservation of chilled chicken should be less than 6 d;p H has certain correlation with water loss rate and shear force.

Effect of Different Initial pH on the Storage Characteristics and Shelf Life of Liquid Diet for Suckling and Weanling Piglets

An experiment was conducted to investigate the effect of different initial pH on the storage characteristics and shelf life of liquid diet. 45 polypropylene bags were allotted to treatments 1, 2 and 3 on average, 100 g diet and 200 g water were placed into each polypropylene bag, food-grade DL-lactic acid was added to each bag at a rate of 0.0 mL in treatment l, 1.2 mL in treatment 2 and 4.7 mL in treatment 3, air was artificially expelled from each bag prior to heat-sealing. All bags were placed into a cage, cooked with steam at 90~C for 30 rain under normal pressure, then taken out and stored from day 0 to 60 at room temperature. Results indicated that liquid diet in treatment 3 achieved the highest total sensory scores, the pH value had a tendency to decrease and the bacteria count had a tendency to increase in the liquid diet with the advancing of storage time with the advancing of storage time, lowering the initial pH of liquid diet decreased the bacteria count, the AFBl and ZEN concentrations and increased the starch gelatinization degree from day 30 to 60, liquid diet in treatment 3 had a lower （P〈0.01） bacteria count and a higher （P〈0.05） starch gelatinization degree at day 30 and 45 than liquid diet in treatment 1. In conclusion, lowering the initial pH of liquid diet with lactic acid to pH 4 could effectively improve the storage characteristics and shelf life of liquid diet.

Microbiota and Shelf Life of Whole and Gutted Pacific Saury(Cololabis saira) During Refrigerated Storage

Pacific saury(Cololabis saira)is usually sold as whole fish in wholesale markets,or in its gutted form which is easy for consumers to cook in retail markets.In order to assess the effect of gutting on the shelf life of Pacific saury during refrigerated storage and reveal the microbial community,fish samples grouped into(I)whole fish and(II)gutted fish were analyzed periodically for sensory,biochemical and microbiological characteristics,and high-throughput sequencing technology was used to investigate the microbiota.Results showed that the sensory score for the gutted fish became unacceptable on day 8,while the whole fish score remained acceptable for 10 days.The total volatile basic nitrogen(TVB-N)value of the gutted fish reached 30 mg N(100 g)^-1 on day 6,while that of the whole samples surpassed 30 mg N(100 g)^-1 on day 10.The thiobarbituric acid reactive substances(TBARS)value of the gutted fish got close to 5.0 mg kg^-1 on day 10,while that of the whole samples surpassed 5.0 mg kg^-1 on day 14.The aerobic plate colony counts(APCs)for the gutted and whole Pacific saury reached 7.0 log10 CFUg^-1 on days 6 and 10,respectively.Organoleptic,biochemical and microbiological analyses revealed that shelf-lives should be 6–8 days for gutted fish and 10 days for whole fish.Microbiota analysis results showed that gutting partly changed the initial microbiota,but didn't alter the dominant bacteria during storage.When the fish were spoiled,high proportion of Pseudomonadaceae was detected in both groups.

Aloe vera Coating Efficiency on Shelf Life of Eggplants at Differential Storage Temperatures

The core objective of instant study was to check the effectiveness of Aloe vera edible coating on postharvest life and physicochemical characteristics of eggplants under different storage temperatures. For this purpose, different formulations of Aloe vera based coating （non-poisonous） was applied at concentration of 0, 0.1%, 0.5%, and 1.0%, respectively on eggplants. The coated eggplants were stored at two different temperatures [10℃ and （30±2）℃] and examined for weight loss, firmness, stem color, shriveling, total soluble solids, pH, acidity, vitamin C, sugar （total sugar, reducing sugar and non-reducing sugar） and N, P, K, Ca and Na for two weeks. The obtained results showed that weight loss, shriveling, total soluble solids, pH, sugar （total sugar and non-reducing sugar） increased and firmness, stem color, acidity, reducing sugar, vitamin C minimized during the storage period. The 0.5% Aloe coating at 10℃ showed significant effect and delayed the changes in above parameters. Aloe vera coating remained almost ineffective in altering nutrient homeostasis （N, P, K, Ca and Na） of eggplants. The optimistic results gained in the current study could additionally investigate in larger market experiments and also could extensive to other tropical/subtropical fruits and vegetables.

Edible Coatings Based on Apple Pectin,Cellulose Nanocrystals,and Essential Oil of Lemongrass:Improving the Quality and Shelf Life of Strawberries(Fragaria Ananassa)

In this work,nine different types of edible coating based on pectin,cellulose nanocrystals,glycerol,and essential oil of lemongrass were prepared and used to coat strawberries with a film formed directly on the surface of the coated fruit.The effects of the different edible coatings on refrigerated fruits in terms of weight loss,titratable acidity,total soluble solids,pH,and anthocyanin content was evaluated after 2 days,4 days,6 days,and 8 days of storage.Application of the edible coatings reduced the weight loss of the coated strawberries and the anthocyanin content.The total soluble solids content of or uncoated fruit increase more markedly than that of coated fruit.In contrast,pH was maintained for both coated and uncoated strawberries.The edible coatings were effective in minimizing of the weight loss,without worsening the physical chemistry attributes.The treatments T5 and T9 presented the best results.

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）.

Sensory Evaluation of Different Packaged Roast Beef Treatments Designed for the Extension of Its Shelf Life

This study was carried out to investigate the effect of different nitrite concentrations on the sensory parameters of roast beef including color, flavor, juiciness, texture and overall acceptability. Four roast beef batches were formulated;the first three treatments were with nitrite concentrations of 0.006%, 0.012% and 0.018% and stored at abused chilling temperature (12°C), while the fourth one was a control treatment with 0.026% nitrite and storage at 4°C. Results showed that increasing nitrite concentration from 0.006% to 0.026% enhanced the shelf life of roast beef stored for 7 days without affecting the sensory characteristics whether at 12°C or 4°C since there were no significant differences (P > 0.05) between all treatments regarding color, flavor, juiciness, texture and overall acceptability. These results could direct us to use high nitrite concentration to protect this product and elongate its shelf life without affecting its preference parameters.

Evaluation of the Shelf Life of Packaged Roast Beef and Some Treatments for Its Extension

This study was carried out to investigate the effect of nitrite concentration, and abused chilling temperature against proper chilling temperature on the chemical, microbiological and shelf life of roast beef stored at 4°C and 12°C. Three roast beef treatments were formulated to investigate the effect of nitrite concentration (0.006%, 0.012% and 0.018%) and abused chilling temperature (12°C) against control treatment (0.026% nitrite and storage at 4°C) on the chemical, microbiological and shelf life. Results showed that roast beef containing 0.026% nitrite and stored at 4°C for 25 days had the lowest thiobarbituric acid (TBA) value while the highest TBA values were in the treatment containing 0.006% added nitrite, stored at 12°C. The aerobic plate count, Enterobacteriaceae, lactic acid bacteria (LAB), and spore former count were increased throughout the storage period which was lower in 0.026% and 0.018% containing nitrite treatments while higher in other two treatments. The lowest percentage of nitrite losses during storage was in the samples having 0.026% added nitrite to roast beef. The results emphasized the risk of abused temperature and the importance of keeping this product under efficient and consistent refrigeration during storage and the use of high nitrite concentration to protect it and elongate its shelf life.

Expression of SAMDC Gene for Enhancing the Shelf Life for Improvement of Fruit Quality Using Biotechnological Approaches into Litchi (Litchi chinensis Sonn.) Cultivars

Polyamines play an important role in plant response to abiotic stress. S-adenosyl-1-methionine decarboxylase (SAMDC) is one of the key regulatory enzymes in the biosynthesis of polyamines. In order to better understand the effect of regulation of polyamine biosynthesis on the shelf life improvement of litchi fruit, SAMDC cDNA isolated from Datura stramonium cloned in pBI121 was introduced into litchi genome by means of Agrobacterium tumefaciens through zygote disc transformation. Transgene and its expression are confirmed by Southern and Northern blot analyses, respectively. Transgenic plants expressing Datura SAMDC produced 1.7- to 2.4-fold higher levels of spermidine and spermine than wildtype plants under normal environmental condition, which indicated that the transgenic litchi presented an enhanced polyamines synthesis compared to wildtype plants. Our results demonstrated clearly that increasing polyamine biosynthesis in plants may be a means of creating improved fruit shelf life germplasm.

Does Chitosan Extend the Shelf Life of Fruits?

The use of hazardous formalin in increasing shelf life of fruits and protecting them from microbial decay by unscrupulous traders is a big health concern for the consumers in Bangladesh. Chitosan is a natural biopolymer produced from the exoskeletons of shrimp and crab, which slows antimicrobial activities and induces immunity of plants against microbial pests. This study aimed to evaluate the efficacy of chitosan on the shelf life extension of some local ripened fruits compared to untreated control. Three doses of chitosan solution viz. 0, 500 and 1000 ppm were sprayed in alternate day on banana (cvs. Shabri and Champa), strawberry, tomato, and oranges. It revealed that chitosan extended shelf life of all fruits by delaying the decay;however, level of protection varied in different kinds of fruits as well as in doses of the chitosan used. Among the tested fruits, decay of tomatoes was most delayed by chitosan. Spraying of both 500 and 1000 ppm of chitosan equally protected 100% decay in tomatoes until 8 days of treatments at room temperature. More than 80% protection of other fruits viz. banana, orange and strawberries by chitosan were recorded at 8, 8 and 4 day after treatment, respectively, which were remarkably higher than the untreated control. Interestingly, 500 ppm of chitosan spray gave better protection than 1000 ppm in all the tested fruits. These results suggest that lower doses of chitosan can be utilized as a natural preservative of fruits alternative to hazardous formalin. A further study with higher number of fruits, and at varying temperature and chitosan doses are needed for recommending it for practical application as a fruit preservative.

Application of Machine Learning Techniques for Okra Shelf Life Prediction

The ability of machine learning techniques to make accurate predications is increasing. The aim of this work is to apply machine learning techniques such as Support Vector Machine, Naïve Bayes, Decision Tree, Logistic Regression, and K-Nearest Neighbour algorithms to predict the shelf life of Okra. Predicting the shelf life of Okra is important because Okra becomes harmful for human consumption if consumed after its shelf life. Okra parameters such as weight loss, firmness, Titrable Acid, Total Soluble Solids, Vitamin C/Ascorbic acid content, and PH were used as inputs into these machine learning techniques. Support Vector Machine, Naïve Bayes and Decision Tree each accurately predicted the shelf life of Okra with accuracies of 100%. However, the Logistic Regression and K-Nearest Neighbour achieved 88.89% and 88.33% accuracies, respectively. These results showed that machine learning techniques especially Support Vector Machine, Naïve Bayes and Decision Tree can be effectively applied for the prediction of Okra shelf 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.

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.

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.

Effects of Edible Micronized Chitosan Coating on Quality and Shelf Life of Sliced Papaya

Papaya pulp is very perishable and has a short shelf life. Manually sliced papayas were treated with 0%, 0.25%, 0.5%, and 1% chitosan (non-micronized and micronized) aqueous solutions;placed into plastic trays, and over-wrapped with PVDC film and then stored at 4°C. Color, soluble solid content, water loss, and total plate count of samples were evaluated. Chitosan coating had the ability to maintain the lightness of the sliced papayas. The a* values of the micronized chitosan-coated sliced papayas were significantly lower than those of the-coated. The sliced papayas that had been treated with 1% MC had a higher total soluble solid content and lower b* value after four days of storage. Also, the chitosan coating on the sliced papaya effectively retarded water loss and inhibited the growth of microorganisms. The results reveal that applying a chitosan coating effectively maintained the quality attributes and prolonged the shelf life of the sliced papayas.

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.

Effects of Sourdough Addition on the Quality and Shelf Life of Chinese Steamed Bread

The effect of adding sourdough with lactic acid bacteria(Lactobacillus plantarum M616) on dough quality and the sensory scores, specific volume, crumb firmness, and spread ratio of resultant Chinese steamed bread were studied. The moisture content of crumb and texture characteristics of the Chinese steamed bread with sourdough during storage were analyzed. In this study, 10%,20%, 30%, and 40% of sourdough addition was investigated. The sourdough starter resulted in significant decrease in the water absorption, development time, stability, and farinograph quality number of the dough. The addition of sourdough improved the quality of Chinese steamed bread such as improving the sensory scores and specific volume, decreasing the crumb firmness, and a lower spread ratio was observed with an increase in the sourdough concentration up to 30%. Sourdough addition delayed a fast decrease in the moisture content of the Chinese steamed bread crumb during storage. The texture profile analysis of the bread crumb indicated that the addition of sourdough improved the quality and delayed the staling speed of Chinese steamed bread during storage.Moreover, inclusion of 30% sourdough produced the best protective effect on product staling.