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...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.展开更多
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 re...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.展开更多
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 compare...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.展开更多
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 moo...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.展开更多
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 su...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. GA<sub>3</sub> at 10, 20, and 30 ppm as against of control were evaluated. Observations on fruit weight (g), fruit firmness (kg/cm<sup>2</sup>), 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 GA<sub>3</sub> at 20 ppm retained higher fruit weight (128.6 g), more firmness (3.54 kg/cm<sup>2</sup>), 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 GA<sub>3</sub> 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 GA<sub>3</sub> at 30 ppm both with ambient (1.02%) and cellar condition (8.21%) as against control with ambient (5.54%) and cellar (21.58%).展开更多
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 surfac...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.展开更多
[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) fo...[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.展开更多
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 ...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.展开更多
Cereal-based foods play an important role as a source of dietary energy and nutrients in human nutrition. The use of microorganisms by humans has a long tradition. Bread making is one of the oldest arts known to man. ...Cereal-based foods play an important role as a source of dietary energy and nutrients in human nutrition. The use of microorganisms by humans has a long tradition. Bread making is one of the oldest arts known to man. Today we know that lactic acid bacteria (LAB) and yeasts are prevailing organisms in carbohydrate-rich environments. They break down carbohydrates to mainly lactic acid, ethanol and CO2. The present study is to determine the effect of Lactobacillus bulgaricus alone and as a combination with yeast (Saccharomyces cerevisiae) using yeast as a control. In this work, different percentage of Lactobacillus bulgaricus were used to investigate how sourdough affect on the bread sensory characteristics such as volume, specific loaf volume, crust, grain, color crumb, aroma, taste, texture, pH of bread and extended shelf life of bread. Also different storage times were used to know it is affected on the shelf life and sensory characteristics of bread. The results suggest that use of sourdough in bread production is useful in improving sensory properties, decreasing fungal spoilage.展开更多
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 o...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.展开更多
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 purpo...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.展开更多
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 chit...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).展开更多
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 b...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.展开更多
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 a...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.展开更多
Fatty acids' ethyl and methyl esters are not natural components of edible vegetable oils and therefore should not be present in virgin olive oils. Among the quality requirements for extra virgin olive oils, the Inter...Fatty acids' ethyl and methyl esters are not natural components of edible vegetable oils and therefore should not be present in virgin olive oils. Among the quality requirements for extra virgin olive oils, the International Olive Council (IOC) Norm, 2015 review, set limits for the ethyl ester content at ≤ 435 ppm for the 2014/2015 and 2015/2016 harvests and at ≤ 30 ppm for the 2016/2017 harvest. The purpose of this paper is to: (a) determine the alkyl ester content in two extra virgin olive oils (of the Arbequina and Coratina varieties) as parameters of quality at the moment of their elaboration and to assess the length of their shelf life, over a 12 month period at room temperature; (b) determine extra virgin olive oils' free alcohols content as these may esterify due to the free fatty acids present during storage. After 6 months of storage, the Arbequina oil's ethyl ester content was 32 ppm, and the Coratina's was 46 ppm. As a result, the shelf life for both was only about half a year (labeling usually indicates it must be consumed "before 1 year"). However, parameters related to oxidation (peroxide index, K 232, K 270 and AK) remained within the limits set by the International Olive Council (IOC) throughout the year. In conclusion: ethyl ester content is a very fine parameter for assessing the quality of extra virgin in an olive oil and determining the length of its shelf life.展开更多
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 understan...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.展开更多
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 biopolym...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.展开更多
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, Na<span style="white-space:n...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, Na<span style="white-space:nowrap;">ï</span>ve 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, <span style="font-family:Verdana;">Total Soluble Solids</span><span style="font-family:Verdana;">, Vitamin C/Ascorbic acid content, and PH were used as inputs into these machine learning techniques. Support Vector Machine, Na<span style="white-space:nowrap;">ï</span>ve 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, Na<span style="white-space:nowrap;">ï</span>ve Bayes and Decision Tree can be effectively applied for the prediction of Okra shelf life.</span>展开更多
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 assess...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.展开更多
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...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.展开更多
文摘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.
基金Introduction of Talents for Scientific Research of State Key Laboratory of North China Crop Improvement and Regulation (Grant No.NCCIR2020RC-11)Hebei Fruit Vegetables Seed Industry Science and Technology Innovation Team Project (Grant No.21326309D)+2 种基金Vegetable Innovation Team Project of Hebei Modern Agricultural Industrial Technology System (Grant No.HBCT2018030203)Introduction of Talents for Scientific Research of Hebei Agriculture University (Grant No.YJ2020048)Basic Scientific Research Funds of Provincial Universities of Hebei Province (Grant No.KY2021056) for the provision of funds。
文摘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.
基金Supported by Scientific Research Foundation of the Education Department of Hubei Province,China(Q20141701)~~
文摘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.
基金Supported by Project of the Department of Education of Fujian Province(JB13317)~~
文摘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.
文摘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. GA<sub>3</sub> at 10, 20, and 30 ppm as against of control were evaluated. Observations on fruit weight (g), fruit firmness (kg/cm<sup>2</sup>), 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 GA<sub>3</sub> at 20 ppm retained higher fruit weight (128.6 g), more firmness (3.54 kg/cm<sup>2</sup>), 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 GA<sub>3</sub> 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 GA<sub>3</sub> at 30 ppm both with ambient (1.02%) and cellar condition (8.21%) as against control with ambient (5.54%) and cellar (21.58%).
文摘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.
基金Supported by Key Research and Development Plan of Jiangsu Province(Modern Agriculture)(BE2015344)Special Fund for Construction of China Agricultural Industry Research System(CARS-41)+1 种基金Three New Engineering Project of Agriculture(SXGC[2017]254)National Natural Science Foundation of China(31572358)
文摘[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.
基金supported by the Jiangxi Key Technology R&D Program,China(2010CCA01300,20121BBF60032)
文摘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.
文摘Cereal-based foods play an important role as a source of dietary energy and nutrients in human nutrition. The use of microorganisms by humans has a long tradition. Bread making is one of the oldest arts known to man. Today we know that lactic acid bacteria (LAB) and yeasts are prevailing organisms in carbohydrate-rich environments. They break down carbohydrates to mainly lactic acid, ethanol and CO2. The present study is to determine the effect of Lactobacillus bulgaricus alone and as a combination with yeast (Saccharomyces cerevisiae) using yeast as a control. In this work, different percentage of Lactobacillus bulgaricus were used to investigate how sourdough affect on the bread sensory characteristics such as volume, specific loaf volume, crust, grain, color crumb, aroma, taste, texture, pH of bread and extended shelf life of bread. Also different storage times were used to know it is affected on the shelf life and sensory characteristics of bread. The results suggest that use of sourdough in bread production is useful in improving sensory properties, decreasing fungal spoilage.
基金Financial support from the National Key R&D Program of China(No.2018YFD0901004)Central Public-interest Scientific Institution Basal Research Fund,YSFRI,CAFS(No.20603022018028)
文摘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.
文摘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.
文摘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).
文摘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.
文摘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.
文摘Fatty acids' ethyl and methyl esters are not natural components of edible vegetable oils and therefore should not be present in virgin olive oils. Among the quality requirements for extra virgin olive oils, the International Olive Council (IOC) Norm, 2015 review, set limits for the ethyl ester content at ≤ 435 ppm for the 2014/2015 and 2015/2016 harvests and at ≤ 30 ppm for the 2016/2017 harvest. The purpose of this paper is to: (a) determine the alkyl ester content in two extra virgin olive oils (of the Arbequina and Coratina varieties) as parameters of quality at the moment of their elaboration and to assess the length of their shelf life, over a 12 month period at room temperature; (b) determine extra virgin olive oils' free alcohols content as these may esterify due to the free fatty acids present during storage. After 6 months of storage, the Arbequina oil's ethyl ester content was 32 ppm, and the Coratina's was 46 ppm. As a result, the shelf life for both was only about half a year (labeling usually indicates it must be consumed "before 1 year"). However, parameters related to oxidation (peroxide index, K 232, K 270 and AK) remained within the limits set by the International Olive Council (IOC) throughout the year. In conclusion: ethyl ester content is a very fine parameter for assessing the quality of extra virgin in an olive oil and determining the length of its shelf life.
文摘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.
文摘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.
文摘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, Na<span style="white-space:nowrap;">ï</span>ve 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, <span style="font-family:Verdana;">Total Soluble Solids</span><span style="font-family:Verdana;">, Vitamin C/Ascorbic acid content, and PH were used as inputs into these machine learning techniques. Support Vector Machine, Na<span style="white-space:nowrap;">ï</span>ve 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, Na<span style="white-space:nowrap;">ï</span>ve Bayes and Decision Tree can be effectively applied for the prediction of Okra shelf life.</span>
文摘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.
基金Financial support by the National Natural Science Foundation of China(No.31301587)
文摘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.