Authors Dr Abdul Jalal, Naveed Ahmad
Postharvest periods are very challenging for the marketing of horticultural commodities that are more perishable. Fruit decay is the major postharvest constraint responsible for the negative return of horticultural commodities that is expressed by weight loss, color changes, softening, and microbial spoilage. Different postharvest techniques like waxing, chemical coating, and dip techniques are in practice to avoid the losses but due to the hazardous nature of chemicals to human health, the concept of bio preservation has been developed, replacing chemical preservation with bio preservation strategies are user friendly and has great potential if constraints in production and application techniques, bio preservative plants, Aloe vera plant has a great history for its medicinal use against a wide range of ailments and fruit preservation. It prevents loss of moisture and firmness, controls respiration rate and maturation development, delays oxidative browning, reduces microorganism proliferation, and other parameters like titratable acidity, soluble solids content, ascorbic acid content, firmness, and decay percentage also controls significantly, Biopreservation is an approach for extending the shelf life of perishable horticultural commodities against microbial decay using natural or controlled microbiota and/or antimicrobial compounds, postharvest technology, application of phytochemicals and plant-based material is safe for extending storage/shelf life of fruits and vegetables. Aloe vera gel as bio preservative is preferred for fruits and vegetable because of its colorless mucilaginous gel, Aloe vera gel has been tested for few fresh fruits by a postharvest and Aloe vera extracts suppressed/retarded postharvest quality losses in Crimson Seedless grapes and Star King cherries , Aloe vera extracts were reported to be useful for Kensington Pride mangoes and Artic Snow nectarines for retaining quality losses after harvest, edible coatings have a various favorable effect on fruits such as imparting a glossy appearance, and better colour, retarding weight loss, or prolonging storage/shelf life by preventing microbial spoilage, the concept of bio preservation is develop to decrease health problems and also provide an edible coating material which not only increase the post-harvest life of fruits and vegetables but also have positive impact on human health, applied Aloe vera gel on pineapple (Ananas comosus) for the extension of its postharvest life, Aloe vera gel application reduces fruit decay and shriveling and browning of the fruit peel, Aloe vera gel as a bio preservative to control postharvest quality losses in fruits, Aloe vera gel application treatment for controlling the postharvest losses, quality characteristics and extending shelf life of fig, treated green grape berries with Aloe vera gel to analyze its effect on the postharvest life of green grape berries, other experiment was coated green gape berries with 0, 1, 5 and 10% w/v Aloe vera gel and stored it in an air tight container for 40 days at the temperature of 15oC, grape berries noted that minimum weight loss, lesser browning, cracking, damage and fungal attack in the berries treated with 5% and 10% Aloe vera gel. The flavor factors (TSS and titratable acidity) were maximum, table grape (Vitis vinifera L. cv. Askari) treated with Aloe vera gel in combination with 2% Cacl2 and 1% citric acid at the temperature of 4oC and 85±5% relative humidity for 35 days in a cold storage. They concluded that the TSS and weight loss of table grapes were reduced with Aloe vera gel application. The ascorbic acid and titratable acidity were also retained and browning and dehydration was delayed by the application of Aloe vera gel to the fruits, Aloe vera gel has the ability to retain the quality and increase the shelf life and market value of grapes, applying Aloe vera gel on the harvested clusters of Gizel Uzum in Iran of (1:3) and (1:4) with salicylic acid of 0, 1 and 2 mmol/L concentrations and stored at the temperature of 0±0.5oC for 90 days, its observed that the phenolic contents, soluble solids and oxidants were conserved by 33% Aloe vera gel and 2 mmolL-1 salicylic acid during the storage, Aloe vera gel as an edible coating on fresh sliced kiwi fruit in four different concentrations i-e 0, 1, 5, 15% (v/v) to maintain its quality. They packed these slices after Aloe vera gel application and kept it at the temperature of 4± 1oC. The respiration rate and microbial spoilage was reduced in slices of kiwi fruit with the application of Aloe vera gel. After seven days, they observed that one logarithmic unit mesophilic load for 15 and 5% coated slices was dropped, stored Button Mushrooms at 4, 10 and 15″C for 13 days after treatment with Aloe vera gel, gum tragacanth and the combination of both. They were analyzed after 2, 4, 6, 8, 10 and 13 days of the storage for physiochemical characteristics. They observed that during cold storage the weight loss, color change and accelerated softening of Mushrooms was delayed with the application of edible coatings, peaches and plums with Aloe vera gel , keep it at the temperature of 20oC for six days. The ethylene production and postharvest quality parameters such as colour change, reduction of acidity and increase in ripening index (total soluble solids/total acidity ratio) were delayed with both treatments. Both the treatment reduced the weight loss, application of Aloe vera gel alone and with the combination of 0.5% ascorbic acids and 1% of citric acids before the storage on pomegranate arils increased its shelf life up to 12 days when stored at 3oC. All the physicochemical analysis like firmness, phenolic components and anthocyanins were maintained during storage. Moreover, there was a high score of sensory evaluations like color, texture, flavor and aroma during this period, when Aloe vera gel is applied with addition of 10 or 2% rosehip oil, it maintained the postharvest quality attributes of prunus species and cultivars, Aloe vera gel applied on peaches (Roma and B-424-16 flat type), plums (Red Beauty and Songria), nectarine (Garofa) and sweet cherry (Brooks) and stored these fruits at the temperature of 20oC for 6 days, analysis of fruits showed that in peaches, plums and nectarine (climacteric fruits) the respiration rate and ethylene production was reduced and the quality parameters such as weight loss, softening, color change and ripening index was delayed as compared to the control, sweet cherry (Prunus avium cv. Napoleon) with Aloe vera gel and nitric oxide by applying 0, 1, 5 and 10 ?mol L-1 nitric oxide and 25 and 33% of Aloe vera gel on the sweet cherry and stored it at the temperature of 1± 0.5″C for 30 days. Due to this treatment the fruit marketability, total phenolics content, vitamin C, catalas enzyme activity, decay index, and weight loss is effectively preserved and the postharvest life was increased with treated fruits, Aloe vera gel as an edible coating for the first time as an alternative to postharvest chemical treatment for a sweet cherry, he application of Aloe vera gel on sweet cherry extended its storability and delatyed the postharvest quality losses like increase in respiration rate, rapid weight loss, and color change, accelerated softening and ripening, stem browning and increased microbial populations in sweet cherry in cold storage, Aloe vera gel is an excellent pre harvest treatment for maintaining the postharvest quality of table grapes. First, they added different concentrations of Aloe vera gel on potato dextrose agar (PDA) for testing the inhibition of mycelium growth of two very common fungi, Penicillium digitatum and Botrytis cinerea which cause fruit decay. The mycelium growth rate of both fungi decreased with Aloe vera concentrations, but to achieve the same growth inhibition, the Aloe vera concentration was 3-fold higher for Botrytis cinerea than Penicillium digitatum, reduction of mycelium growth for Penicillium digitatum was 4 logarithmic units and 2 logarithmic units for Botrytis cinerea was 250 mmol L-1. They applied this dose of Aloe vera gel on table grapes vineyard 7 days before harvesting. The respiration rate and weight loss were reduced and ripening rates such as color and firmness were delayed in table grapes when stored for 35 days in cold storage after harvest, table grapes cv. Crimson (seedless table grapes) with Aloe vera gel due to which the weight loss, color change, accelerated softening and ripening, rachis browning, and berry decay were significantly delayed and its shelf life was extended up to 35 days at 1″C, an experiment on mango fruit (Var. Ngowe) keeping in view its perishable nature and short post-harvest life. The Aloe vera gel at concentrations of 0, 25, 50, and 75% was applied to the mango fruits with the combination of 1% chitosan and stored at the temperature of 13oC for 20 days. It was concluded that both 50 and 75% of Aloe vera gel prolonged the shelf life of mango. Percent weight loss, total soluble solids, and fruit firmness reduced during storage with this treatment, however, a 50% concentration of Aloe vera gel also maintained the pH of mango fruits during storage, stored three hundred and twenty (320) oranges (Var. Valencia) in the refrigerator for eight (8) weeks. Half of these fruits were treated with Aloe vera gel and half remained untreated as a control. It was revealed that the orange fruits that were treated with the Aloe vera gel showed the best result regarding the post-harvest life as compared with the control. The percentage of weight loss was conserved by the application of Aloe vera gel. While there was a line increase in the other parameters like sugar-acid ratio and total soluble solids. A pH of the orange was also maintained with the application of Aloe vera gel, papaya fruit treated with Aloe vera gel at the concentration of 100% and also with the papaya leaf extract in combination with Aloe vera gel at the ratio of 1:1 and stored it at room temperature of 25 to 29oC with the relative humidity of 82 to 84% for 16 days, concluded that Aloe vera gel alone and with the combination of papaya leaf extract prolonged the shelf life of papaya and significantly affected its physicochemical characteristics as compared to the control, decay of papaya fruits started on the 6th day of storage and completed in 12 days in the control. However, the treated fruits did not show any sign of decay for up to 12 days, and on the 16th day of storage the treated papaya fruits decayed. The color score, fruit firmness, ascorbic acid, and flavor of the treated papaya fruits were maintained for up to 12 days. There was 27% of disease incidence in the papaya fruits treated with Aloe vera gel alone and 13% disease incidence was recorded in the papaya fruits treated with papaya leaf extract with the combination of Aloe vera gel. While there was 100% disease incidence in the papaya fruits that remained untreated, Aloe vera gel as an edible coating and the best alternative for the chemicals used in the post-harvest treatment for the horticultural commodities, strawberry fruits treated with Aloe vera gel and refrigerate it for 16 days concluded from the physicochemical analysis that the application of Aloe vera gel extends the postharvest life of strawberry fruits, also an increase in the color change, weight loss, decay and loss of firmness in the strawberry fruits remained uncoated during cold storage. On the other hand, the strawberry fruits treated with Aloe vera gel (1:3) reduced the weight loss, firmness, and TSS. Sensory evaluations such as aroma, color, taste, and flavor are also maintained by Aloe vera gel during storage. Aloe vera gel (1:3) was applied on the postharvest life of Jujube fruits and stored it at the temperature of 5±2oC for 45 days. The organoleptic and physicochemical analysis of Jujube fruits showed that Aloe vera gel maintained all the postharvest parameters of Jujube fruits treated with Aloe vera gel while the untreated fruits lose their physical as well as chemical characteristics after 21 days of storage. They also revealed that Aloe vera gel has antifungal properties and reduced the microbial growth of fungi and bacteria. Aloe vera gel also significantly affected the sensory evaluation of Jujube fruits, Aloe vera gel (1:2) used on the Sapota (Manilkara zapota) fruits to prolong its shelf life, reduce the fungal and bacterial growth and maintain all its quality attributes including sensory evaluation, using dip technique for this purpose and dipped all the fruits in the Aloe vera gel for 7 minutes and then stored it in cool temperature of 5±2oC for 20 days, both the treated and untreated fruits showed that the quality attributes of untreated sapota fruits loss all the quality attributes after 10 days of storage however the sapota fruits treated with Aloe vera gel retained all its quality attributes up to 20 days, Aloe vera gel have the antifungal and antibacterial properties and used as an edible coating for the horticultural commodities for prolonging the shelf life, Aloe vera gel has polysaccharide and act as a barrier for the moisture loss and oxygen for fruits and vegetables, Aloe vera gel prolonged the shelf life of fruits and vegetables and all the quality attributes such as color, appearance, aroma and flavor are maintained, Aloe vera gel also decrease the disease incidence within the horticultural commodities, combination of chitosan on the cucumber to improve its quality and extend it postharvest life. They stored the treated cucumber at the temperature of 25oC for 7 weeks, post-harvest quality attributes like TSS, firmness, ascorbic acid contents, acidity and weight loss were maintained with Aloe vera gel treatment as compared to the control, effect of Aloe vera gel on the postharvest life of oranges fruits with Aloe vera gel and stored at the temperature of 27oC, increase in the weight loss, firmness and TSS in the untreated fruits while retained in the fruits treated with Aloe vera gel, shelf life of oranges increased up to 5 days without any negative changes in its quality parameters.
