Behaviour Of Apples Research Articles

Apples from Monalisa – biological variation of firmness behaviour in storage and shelf lifeaa To the memory of Marjan Simčič (1960-2016), believer in and promotor of studying biological variation from the start.

Apples are long-term stored in quite similar CA conditions, expecting the behaviour during that storage to be the similar for all apples, only affected by cultivar and picking time. The aim of this study, within the Monalisa project, is the effect of growing conditions on the firmness behaviour of apples during postharvest CA storage and shelf-life. Apples of two cultivars (‘Braeburn’, ‘Kanzi’) were harvested from four orchards (different altitudes and different crop loads) and stored in commercial CA storage for nine months. Samples of 30 apples were taken from CA storage every one or two months and subjected to storage at room temperature. Apples were assessed on firmness shelf-life. Firmness measurements were carried out using the (destructive) puncture test and the (non-destructive) Aweta firmness meter. The first and overwhelming outcome of this study is the huge variation in firmness and the almost absence of firmness decrease of ‘Kanzi’ apples both during CA and shelf-life. The huge variation was tackled by novel statistical analysis techniques (probelation, quantile regression) and assuming a logistic behaviour. Data sets were analysed including the biological variation between individual fruit with explained variation (R2 adj) often over 90%. Only minor effects of the CA duration on the rate of firmness loss during shelf life could be indicated. Altitude has a major effect on the level of firmness while crop load has less effect. Likely, higher altitudes result in lower growing temperatures and therefore in a lower rate of cell division during the early growth phase, which results in smaller and firmer apples. Crop load likely affects the amount of available photo assimilates per fruit. Higher crop load results therefore in smaller and firmer apples. These results clearly show that, up to now, the huge biological variation in the orchard prohibited progress in orchard dependant storage management.

Development of a visco-elastoplastic contact force model and its parameter determination for apples

A contact force model was developed to model the visco-elastoplastic (VEP) behaviour of apples. The model is based on the elastoplastic Thornton model and has been written in a pressure-based formulation to extend the application of the model to Discrete Element Method (DEM) simulations with arbitrary rounded shapes. The parameters of the new developed VEP contact force model were determined by fitting the experimental data acquired from Jonagold, Joly Red and Kanzi apples impacted by a pendulum. With only one parameter set per cultivar and for a large impact range (impact velocity range: 0.3–1.5m/s), the VEP-model (R2=0.90±0.13) provides a better description of the force-deformation profiles than the viscoelastic Kono and Kuwabara (KK) model (R2=0.71±0.20). The equivalent Young’s modulus (E*) was also determined under quasi-static conditions, which resulted in measured E*-values for Jonagold, Joly Red and Kanzi apples of respectively 4.24±0.96MPa, 5.09±1.27MPa and 7.82±0.41MPa. The novel VEP-model has the potential to help predict and understand bruise damage in apples as well as other horticultural products.

A Novel Data Preprocessing Method for the Modeling and Prediction of Freeze-Drying Behavior of Apples: Multiple Output–Dependent Data Scaling (MODDS)

In the present study, the freeze drying behavior of apples have been modeled and predicted. Because freeze-drying is a very expensive and complex process, modeling of the freeze-drying process is a challenging task. In this study, a novel data scaling method called multiple output–dependent data scaling (MODDS) has been proposed and combined with an adaptive neuro-fuzzy inference system (ANFIS) to forecast the moisture content (MC), moisture ratio (MR), and drying rate (DR) values, which are outputs of freeze-drying behavior of apples. The input parameters of the freeze drying system are the sample thicknesses, drying time, pressure, relative humidity, chamber temperature, and sample temperature. Using the input parameters, the outputs of the freeze-drying process of apples were predicted using a hybrid system based on MODDS and ANFIS. In the first stage, only input parameters were scaled using MODDS. In the second stage, the outputs of freeze drying of apples were predicted with the scaled input parameters using ANFIS algorithm. Ninety-two samples were included in the data set, including 10-, 7-, and 5-mm samples. In order to evaluate the performance of the proposed model, the mean absolute error (MAE), mean square error (MSE), root mean square error (RMSE), coefficient of determination (R 2), index of agreement (IA), and mean absolute percentage error (MAPE) were used. Though MSE values of 2.48, 0.035, and 0.011 and IA values of 0.887, 0.887, and 0.466 were obtained for MC, MR, and DR, respectively, using the ANFIS prediction algorithm the hybrid MODDS-ANFIS model achieved MSE values of 0.003, 0.00005, and 0.00007 and IA values of 0.999, 0.999, and 0.993 for the prediction of MC, MR, and DR, respectively. The results obtained demonstrate that the proposed hybrid system is a robust and efficient method for the modeling and prediction of freeze-drying behavior of apples.

Apple's Leopard Versus Microsoft's Windows XP: Experimental Evaluation of Apple's Leopard Operating System with Windows XP-SP2 under Distributed Denial of Service Security Attacks

ABSTRACT Apple's iMac computers are promoted by Apple Inc. to be secure, safe, virus free, and fast computers. In this experimental paper, we evaluate the security offered by the iMac with its usual Leopard Operating System, against different Distributed Denial of Service (DDoS) attacks in a Gigabit LAN environment. We compared the effect of DDoS attacks on Leopard OS against those on the Window's XP-SP2 when installed on the same iMac platform under the same network attack environment. DDoS-based flooding attacks can originate in a LAN environment or can be from the Internet, which can have an impact on a victim computer with a barrage of Denial of Service (DoS) packet requests, thereby exhausting the resources of the victim computer in processing these requests. To study the impact on iMac computers, we created the corresponding DDoS traffic in a controlled lab environment to test against iMac computer that first deployed Leopard OS. Later, the same iMac platform was made to use Window's XP OS. We compared the behavior of Apple's Leopard OS with Windows's XP-SP2 OS under Ping Flood, ICMP Land, TCP-SYN, Smurf Flood, ARP Flood, and UDP Flood attacks. It was found that the Apple's iMac computer using its usual Leopard operating system crashed even under low bandwidth of ARP-based attack traffic, requiring forced reboot of the iMac computer. Interestingly, when compared with Microsoft's Windows XP-SP2 operating system, deployed on the same iMac platform, the computer was able to sustain the attack and did not crash. Our discovery of this vulnerability shows that Apple's popular operating systems, namely Leopards, commonly deployed on iMacs are prone to crash under ARP-based security attacks. Also in other attacks Windows XP-SP2 was found to have a better performance than Leopard in terms of resource consumption.

A COMPARATIVE STUDY OF 'GOLDEN DELICIOUS' AND 'FUJI' APPLES PRODUCED BY ORGANIC AND INTEGRATED SYSTEMS IN THE NORTH-EAST OF SPAIN

The objective of our research was to compare the postharvest properties of organic and integrated production systems in apples (Malus domestica Borkh., 'Golden Delicious' and 'Fuji Kiku-8') from the region of Lleida (NE Spain). Fruit were obtained from integrated and organic experimental orchards except for the organic 'Golden Delicious' apples which were obtained from a commercial orchard. All orchards had similar climate and soil characteristics. 'Golden Delicious' and 'Fuji' apples were harvested in the commercial harvest window in 2005 and stored in air for 4 or 5 months, respectively. Ethylene production, firmness, total titratable acidity (TA) and soluble solids content (SSC) were analysed at harvest time and after cold storage (fresh and after 7 days of shelf-life at 20°C). After storage and shelf life, physiological disorders were evaluated and a non-trained consumer panel tasted the apples to establish their sensory attributes. Although harvested on the same day, non-organic fruit were generally more mature compared with organic fruit, as indicated by a higher ethylene production. Additionally, organic 'Golden Delicious' apples showed higher TA whereas no difference was found in SSC compared with the integrated samples. There was no difference in the TA between organic and non-organic 'Fuji' apples but firmness and SSC were significantly higher in the non-organic fruit. For both cultivars, organic fruit developed fewer physiological disorders during cold storage: fewer 'Golden Delicious' apples developed bitter-pit and 'Fuji' apples presented less lenticel breakdown. Quality assessment and sensory evaluation both indicated that organic 'Golden Delicious' apples were more sour and organic 'Fuji' apples more sweet than those produced by integrated systems. However, hedonic scale values showed no clear differences in the general sensory qualification. Collectively, these results show that the production method (organic versus integrated) and the cultivar may have a significant influence on the postharvest behaviour of apples.

HOW TO CHOOSE CRITERIA TO HARVEST APPLES. THE DYNAMICS OF MATURITY

The storage behaviour of apples is simulated with a model based on the changes in green ground colour of three apple cultivars (`Elstar?, `Topaz? and `Pinova?) during ripening on the tree in the same orchard in three consecutive seasons, and also the effects of at-harvest maturity criteria. Taking the variation over the seasons into account (mainly found in the potential greenness), using a fixed fraction of ground colour at the moment of harvest as a harvest criterion was found to exhibit a better performance than using a harvest criterion of a fixed colour. The second part of the paper deals with theoretical relations between the product properties at the moment of harvest. These relations constitute the calibration curve per season for harvest indices like the Streif index. Variations in properties due to different seasonal conditions can affect the range of colour, as indicated in previous examples, and the synchronisation in the biological shift factor for different properties (here colour and firmness). The first effect (colour range) generates a change in slope between the two variables (colour and firmness), the second one a parallel shift. These findings can be used to improve the general performance of harvest indices over the seasons and orchards.

Rehydration of Apple Dried by Different Methods

Apple var. Idared cut into cubes was dried by convection and freeze-dried. Dried cubes were equilibrated to variable water activities by storage over saturated salt solutions (range 0–0.33). Rehydration was done for one hour in water at 20°C. Increase in both mass and volume of cubes was followed during rehydration. Changes in height of a cube were recorded using a minimal displacement gauge. Electron transmission microscopy was used to measure cell wall thickness in raw and rehydrated material. Modes of drying affected the behavior of apple cubes upon rehydration. Convective dried apple imbibed water and swelled during rehydration, and a collapse of structure was observed at the beginning of the wetting process. Analysis of both mass and volume increase showed that at the beginning of rehydration capillaries and pores were filled with water and thereafter swelling of biopolymers occurred. Cell walls imbibed water, but their thickness after one hour of rehydration was half of that of raw apple. Freeze-dried apple increased in mass much faster than these dried by convection. Rehydration caused collapse of structure, which was not rebuilt during further wetting. On the other hand, cell walls swelled significantly during rehydration and reached thickness almost that of raw apple. It was inferred that freezing injured tissue, which after drying contained numerous discontinuities. Hence, swelling of domains, which did not form a continuous structure, was not propagated and expressed by the increase in volume on a macroscopic scale. Initial water activity of both investigated materials affected collapse of structure during rehydration. The higher the water activity, the faster the collapse.

RELATIONSHIPS BETWEEN PREHARVEST HORTICULTURAL OIL APPLICATION AND POSTHARVEST BEHAVIOUR OF ´GOLDEN DELICIOUS´ APPLES: EFFECT ON VOLATILE AROMA PRODUCTION

Traditionally, petroleum-based horticultural oils are applied throughout the growing season to apples (Malus ×domestica Borkh.), although plant-based oils, like soybean oil, have shown to be just as effective. However, the influence of oil applications on fruit quality and storage behaviour of apples is not well understood. To study the effect of growing season-applied soybean oil on volatile aroma production, three single treatments (midseason, 21 days before harvest, 3 days before harvest) of soybean oil emulsion (1% food grade oil, 0.1% Latron surfactant) were administered. 'Golden Delicious' apples were harvested at commercial maturity and stored for up to 6 months at 0.5°C in air (RA) or under 2 kPa O 2 and 0.2 kPa CO 2 controlled atmosphere storage (CA). Application of soybean oil emulsion 21 days before harvest resulted in apples with consistently higher mean volatile production, mainly due to aldehyde (hexanal, 2-hexenal) levels higher than controls. The loss of alcohols (mainly butanol, 2-methylbutanol) due to prolonged CA storage was diminished by oil-treated fruit. More alcohols (butanol, 2-methyl butanol) were regenerated after 7 days of shelf-life. Compared with control fruit, only apples treated with soybean oil emulsion 3 days before harvest emitted higher amounts of esters (butyl acetate, 2-methyl butyl acetate) corresponding to the alcohol precursors. The application of soybean oils during the growing season may potentially improve the retention and regeneration capacity of important volatile compounds contributing to the aroma of 'Golden Delicious' apples.

Prediction of Bruising in Impacted Multilayered Apple Packs

ABSTRACT A method for predicting total bruising and bruise dis-tributions in apple packs under impact loads is given. The method takes into account the variables to be expected in distribution systems such as bruise resis-tance, numbers of layers, package rebound and impact conditions. It is based on the correlation between bruis-ing and absorbed energy and calculates the absorbed energy at each interface in a multilayered arrangement. It is postulated that the behavior of apples in commercial multilayered packages is similar to that of apples in single columns. Results calculated for Jonathan and Granny Smith ap-ples in columns up to 10 deep for a variety of package and impact conditions are in good agreement with ex-perimental values. The method can be used to evaluate packaging and handling systems and should have wide application to other products transported in multilayered packs.

Some effects of the composition of the storage atmosphere on the behaviour of apples stored in polyethylene film bags

Experiments were carried out during a period of five years with Jonathan, Delicious, and Granny Smith apples, stored at 32�F in polyethylene film bags. After storage for five to seven months best retention of ground colour, least weight loss, and least wastage from superficial scald and low-temperature breakdown were obtained in bags in which the levels of oxygen were low (minimum 3.6 per cent), or in those in which the levels of carbon dioxide were high (maximum 6.7 per cent). Low-temperature breakdown was decreased markedly when calcium chloride was placed inside the bags to reduce the humidity. The use of calcium hydroxide to absorb carbon dioxide did not reduce the disorder.

The Influence of Soil Environment on the Behaviour of Apple and Plum Cuttings

The Influence of Soil Environment on the Behaviour of Apple and Plum Cuttings

The Influence of Source and Growth Substance on the Behaviour of Apple and Plum Cuttings

The behaviour of hardwood cuttings is influenced by factors that have operated upon the parent plant. A comprehensive study, not only of such " source ” effects but also of their interaction with growth substance treatment and subsequent environment, aims to extend this method of propagation. Patterns of behaviour of varieties of very different rooting capacity are clearly related, layer cuttings being better than hedge, with a declining gradient from the base of the shoot. The etiolated basal cutting from a layer shoot normally roots well whenever planted, but non-etiolated cuttings derive considerable benefit from over-wintering in soil.With the readily rooting Myrobalan B, growth substance application in the autumn is not essential ; such treatment is advocated for the moderately rooting Brompton plum while, with the shyly rooting Crab C, accelerative influence has, so far, proved inadequate. Success with Crab C could derive from the ability of the cutting to survive, though unrooted, into the second year when rooting normally follows. Spring planting and absence of growth substance stimulation enhance this chance.Brompton cuttings have medium power to survive, whereas Myrobalan B cuttings have only low, so that they are liable to succumb when conditions are adverse. The survival factor may contribute considerably towards the rooting gradient and must be distinguished from inherent rooting capacity.When the rooting of non-etiolated cuttings is satisfactory the relative disparity of hedge compared with layer cuttings diminishes, and hedge culture is highly favoured for supplying cuttings.Elevation of hitherto shy-rooting varieties to high levels depends upon further adjustment both of growth substance treatment and subsequent environment.

Effects of skin coatings on the behaviour of apples in storage. IV. Comparisons of skin coatings and gas (controlled atmosphere) storage.

The effects on apples of gas (controlled atmosphere) storage and of skin coatings in refrigerated storage have been compared using the varieties Jonathan, Delicious, and Granny Smith. With Jonathan gas storage prolonged storage life more than coatings. Although with Delicious, gas storage was somewhat better than coating, the gain by either method was small. With Granny Smith coatings were generally more successful than gas storage. This was due to better control of superficial scald and senescent scalds. Both gas storage and skin coatings prolonged storage life, primarily by increasing the carbon dioxide tension and decreasing the oxygen tension inside the apple. However, differing effects on the volatile products of metabolism, other than carbon dioxide, caused important differences in the behaviour of the fruit.

Effects of skin coatings on the behaviour of apples in storage. III. Cool storage investigations.

The effects of skin coatings on several varieties of apples during cool storage were studied in several seasons from 1941 to 1946. Most of the work was done with the Granny Smith and Jonathan varieties and coatings tested included alcoholic solutions of castor oil and shellac (C.O.S.), oil emulsions, and wax emulsions. With most varieties the more successful coatings, under favourable conditions of fruit maturity and of temperature before and after storage, reduced wastage and retarded loss of condition. The most successful coating, a 7-10 per cent. C.O.S. solution, increased commercial cold-storage life of a number of varieties by 25-30 per cent. C.O.S. and some oil coatings controlled superficial scald, but to a less degree than good oiled wraps. Most coatings controlled Jonathan spot and senescent disorders, but only the alcoholic solutions reduced mould wastage. Coatings at times caused direct injury to the fruit, but under favourable conditions this was usually not of commercial significance. Skin blemishes, internal disorders, and off-flavours were often severe in coated apples exposed to temperatures above 700°F either before or after cool storage. Wrapping in either plain or oiled wraps improved the out-turn of coated fruit.

Effects of skin coatings on the behaviour of apples in storage. 2. Common storage investigations.

Apples of several varieties, particularly Granny Smith, were held in common (unrefrigerated) storage after treatment with skin coatings. Under favourable conditions their storage life was increased by about 50 per cent., the greatest increase being with early varieties. Undesirable side effects are described and their relation to storage conditions discussed. The most important factors influencing the storage behaviour of coated apples were temperature and maturity. Temperatures above 70°F, even for comparatively short periods, led to fermentation and alcoholic breakdown. Fruit picked at the optimum stage for cool storage held best after coating; picked either before or after this stage, it developed disorders in storage. The best coating tested was an 8-10 per cent. alcoholic solution of 2 parts of castor oil and 1 part of wax-free shellac (C.O.S.). It was satisfactory with most varieties in cool conditions, but sometimes caused slight spotting at the lenticels. Emulsions of medicinal-grade paraffin oil, alone or mixed with castor oil, were satisfactory on most varieties (e.g. Granny Smith) which develop a copious natural waxy coating. Waxes were also applied as emulsions; the best was a mixture of 2 or 3 parts of paraffin wax with 1 part of carnauba or lac wax. Emulsion coatings were generally improved by adding 25 per cent. of wax-free shellac in 3 per cent. ammonia. C.O.S. was more effective than oil coatings and both were more effective than waxes in retarding ripening and in controlling disorders of senescence. Waxes reduced shrivelling much more than the other coatings. All coatings controlled Jonathan spot and greatly reduced bitter pit. Only the alcoholic solutions reduced mould, which was often increased by emulsions.

Effects of skin coatings on the behaviour of apples in storage. I. Physiological and general investigations.

The effects of skin coatings on the physiological behaviour of apples have been investigated and a mechanism for the effects has been suggested. Using mainly the variety Granny Smith, the composition of the internal atmosphere, respiration rate, and other changes associated with ripening have been studied in both uncoated and coated apples. The effects were found to depend greatly on temperature, thickness and type of coating, and variety and condition of the fruits. Coating increased the resistance of the skin to gaseous diffusion and thus greatly reduced the internal oxygen concentration, increased the internal carbon dioxide concentration, reduced the respiration rate, and retarded ripening changes by varying degrees. The most spectacular effect on ripening was a marked retardation of normal yellowing of the skin, which is mainly controlled by internal oxygen supply.

Apparatus for the Measurement of Gaseous Conditions inside an Apple Fruit

IT was noticed in the course of studies of the behaviour of apples which had been coated with various oil-water emulsions (see e.g. Hulme, 1949) that some of the fruits exhibited symptoms of physiological diseases typical of fruit stored in low concentrations of 02 and high concentrations of C02 (see Kidd and West, 1927). This suggested that the effect of skin-coatings on the storage behaviour of the fruit was related to their effect on the composition of the atmosphere within the fruit and that to study these effects it was necessary to measure the content of C02 and Oa within the fruit. Considerable variation in behaviour was observed in fruit treated with the