The Effect of Porang Coating Application and Storage Time on The Characteristics of Kintamani Siamese Oranges

. Kintamani Siamese Orange is one of Indonesia's leading fruits with a distinctive taste, sweet with a slight sourness. One of the efforts to increase the shelf life of Kintamani Siamese Orange is by coating using edible materials. The edible coating can be made using renewable natural materials, one of these natural ingredients is porang starch. Porang coating is a thin layer made from glucomannan porang tubers. The application of the coating is needed to improve the appearance and maintain the quality of Kintamani Siamese citrus fruits. The motive of this examination was to decide the impact of porang coating type and storage time on the characteristics of Kintamani Siamese orange. This observation used a factorial randomized group design with two treatment factors, namely the type of porang coating (without coating, coating, and nanocoating), and the storage time of oranges (5 days, 10 days, 15 days). The best characteristics of Kintamani Siamese Orange were obtained from the treatment of porang nanocoating application with criteria of fruit weight shrinkage value of 12.47%, acidity (pH) of 4.30, total dissolved solids of 15.77ºBrix, moisture content of 94.21%, vitamin C of 78.55 and the amount of damaged fruit of 20.00% up to 5 days storage.


Introduction
Bali is one of the regions in Indonesia that has the potential for various types of horticulture, one of which is oranges.Bali Province has a strategic position in the development of the agricultural sector, especially the plantation subsector.Many citrus plants are grown in Bali, especially Siamese oranges.Oranges also play an important role in the economy, especially as a provider of employment and a source of income.Siamese orange production in Bangli Regency continues to increase, namely in 2018 by 106,029.10 tons, and by 2,532,062 tons in 2019 [1].Siamese citrus fruits have a sweet and fresh taste with a sweetness level of 13.5 o Brix so they are in great demand by consumers [2].In addition to the physical and chemical best of the fruit, the shelf life of the fruit is very important and also needs to be considered.Good fruit quality begins when harvesting is carried out, namely at the right level of ripeness [2].The shelf life of fruit is one of the parameters that has an important role in fruit trade.Efforts to extend shelf life are made by minimizing metabolic processes such as suppressing the rate of respiration through regulating environmental conditions, storage, and packaging.[3].
The use of plastic packaging is currently avoided because it is difficult to biologically overhaul so it can pollute the environment.For this reason, it is necessary to find alternatives to other packaging materials that have superior properties such as plastic, and are biodegradable and can even be consumed by humans (edible) so that the burden of contamination to the environment can be reduced [4].The edible coating is an alternative to replacing plastic because it is biodegradable while acting as a barrier.The application of edible coating has been done for a long time, such as wax coating on fresh fruits and vegetables [5].In addition to extending the shelf life of post-harvest foodstuffs, small cuts and scratches on the surface of oranges can be covered by the application of edible coating.Another obvious advantage of coating is the increased gloss of the fruit as well as improving the appearance of the orange so that it is more acceptable to consumers [6].
Edible coatings can be derived from easily renewable raw materials such as mixtures of lipids, polysaccharides, and proteins, which function as a barrier to water vapor, gases, and other solutes and function as carriers of various ingredients such as emulsifiers, antimicrobials, and antioxidants.The edible coating can be made using renewable natural materials, one of these natural ingredients is porang starch [7].The advantage of using porang starch in making edible coating is that it can produce a coating that has strong adhesion, based on its bonding properties, porang starch is better when compared to other adhesives such as corn and rice.[8].Nanocoating covers materials with coatings at the nanometer scale or to cowl nanoscale entities.A nanocomposite consists of combinations resulting in materials that generally have from or greater special materials with nanometer size, being specific because of the mixed homes and/or structuring outcomes of components.Nanocomposite solutions are solutions made from a combination of several materials in which at least one of the materials is less than 100 nanometers in size.The use of biopolymers as raw materials for coating solutions because they are edible and biodegradable so they are more environmentally friendly [9].Research and use of porang coating type as Siamese Kintamani orange coating has not been researched.Based on this, it's far necessary to research the application of porang coating types and garage time at the traits of Kintamani Siamese Orange.

Material and methods
These studies became accomplished from January -to April 2023 at the Food Processing Laboratory and Analysis Laboratory, Faculty of Agriculture, Warmadewa University.The study used a factorial pattern Group Randomized Design with 2 factors.Factor I: type of treatment without porang coating, porang coating, porang nanocoating.Factor II: day 5, day 10, day 15.The parameters of this study are fruit weight loss measurement using digital scales, acidity measurement using a pH meter, total dissolved solids measurement using a refractometer, moisture content measurement using digital scales, and vitamin c measurement using spectrophotometry tools.The records acquired were analyzed with ANOVA fingerprints.The results of the fingerprints that showed a real effect (P<0.05) to very real (P<0.01)had been observed via way of means of a 5% LSD (Least Significance Different) take a look at from if the effects of the diverse remedy fingerprints confirmed interaction, then endured with the multiple distance test from Duncan's Multi Range Test.

Fruit weight shrinkage
Fingerprint analysis confirmed that the coating type treatment and storage time and interplay had an intangible effect (p>0.05) on the characteristics of Kintamani Siamese Orange.The results of the highest fruit weight shrinkage analysis were obtained from uncoated treatment with a storage life of 15 days, which is 33.10%.While the lowest fruit weight shrinkage was obtained in the treatment of the porang nanocoating application, the storage time of 5 days was 12.47%.The consequences of the weight reduction analysis of Kintamani Siamese Citrus fruit may be visible in Table 1.
The results of research that have been conducted show differences in fruit weight shrinkage test values in each treatment with different shelf life.In general, the weight shrinkage value of citrus fruits during room temperature storage has increased.The boom in fruit weight loss in oranges is caused by transpiration and respiration.The increase in fruit weight loss value is caused by several factors including loss due to respiration, so that oranges experience damage caused by water loss in citrus fruits without treatment so that the weight shrinkage is higher.Applying nanocoating to oranges has an effect so that CO2 or respiration rate in oranges is not too high [10].

Degree of acidity (pH)
Fingerprint analysis confirmed that the coating type treatment and garage time and interplay had a totally huge effect (p>0.01) on the characteristics of Kintamani Siamese Orange.The highest acidity (pH) analysis results were obtained from coating treatment with a storage life of 10 days, which is 4.81.While the lowest degree of acidity (pH) was obtained in the application treatment without coating porang, the storage time of 10 days was 4.01.The results of the acidity (pH) analysis of Kintamani Siamese Oranges may be visible in Table 2.The results of research that have been conducted show that there are differences in the value of the degree of acidity in each treatment with a different shelf life.The pH value can indicate the alkalinity or acidity of a foodstuff, the lower the pH value (<7), the greater the degree of acidity.If the molecule touches the quantity 7 or has the equal quantity among acid and base, it's miles known as neutral [11].This is because coating with nanocoating can maintain the quality of fresh oranges because it can inhibit weight loss, and water loss, reduce sugar formation, and maintain pH, total organic acids, and vitamin C during storage [12].

Total dissolved solids
Fingerprint analysis showed that the coating type treatment and garage time and interplay had a completely considerable effect (p>0.01) on the characteristics of Kintamani Siamese Orange.The maximum total dissolved solids analysis results were obtained from uncoated treatment with a storage life of 10 days, which is 17.70 ºBrix.While the lowest total dissolved solids obtained in the treatment of nanocoating application porang storage time of 5 days, which is 15.77ºBrix.The consequences of the analysis of the total dissolved solids of Kintamani Siamese Orange can be seen in Table 3.The results of research that have been conducted show a difference in the total value of dissolved solids in each treatment with different shelf life.The higher the Total Dissolved Solids (TDS), the higher the sweetness of the fruit.The increase in TDS value is due to the reduction in moisture content that occurs in oranges during storage.The less water content in oranges, the TDS will increase with the period of garage time.This means that the nanocoating treatment can shape a layer that is right sufficient to suppress the technique of breathing and transpiration so that it may inhibit the growth in TDS content [11].

Water content
Fingerprint analysis confirmed that the coating type treatment and storage time and interaction had a very significant effect (p>0.01) on the characteristics of Kintamani Siamese Orange.The highest moisture content analysis results were obtained from nanocoating treatment with a storage life of 5 days, which is 94.21 ºBrix.While the bottom moisture content material became received inside the remedy of the porang nanocoating application, the storage time of 15 days was 87.64 ºBrix.The results of the water content analysis of Kintamani Siamese Oranges are visible in Table 4.The results of research that has been conducted show that there are differences in the value of moisture content in each treatment with different shelf life.Water evaporation in Siamese Kintamani oranges that occurs during storage poses can cause weight loss and water loss and can damage or degrade the quality of oranges.Generally, fruits have a high water content, which ranges from 65%-90% [11].This is because citrus fruits ripen faster than citrus fruits that are added to nanocoating solutions which makes the water content in oranges increase.Thus, the nanocoating solution will inhibit the ripening process of the fruit.The advantage of using porang starch in making edible coating is that it can produce nanocoatings that have strong adhesion [8].

Vitamin C
Fingerprint analysis showed that the coating type treatment and storage time and interaction had a significant effect (p>0.05) on the characteristics of Kintamani Siamese Orange.The highest vitamin C analysis results were obtained from nanocoating treatment with a storage life of 10 days, which is 82.83.While the lowest vitamin C obtained in application treatment without porang coating, the storage time of 15 days is 50.08.The results of vitamin C analysis of Kintamani Siamese Oranges may be visible in Table 5.The results of research that have been conducted show a difference in the value of vitamin C in each treatment with a different shelf life.The lower Vitamin C content material results from the evaporation or diffusion of water.The decrease in vitamin C is caused by the nature of vitamin C which is easily soluble in water.Vitamin C is a vitamin that is easily damaged, easily soluble, and easily oxidized [13].This is associated with the primary fabric of fit to be eaten coating that's hydrophilic and has right barrier houses towards oxygen, carbon dioxide, and lipids.The presence of an fit to be eaten coating can inhibit the access of oxygen into the fruit that's the cause of vitamin C damage through oxidation reactions.The results of vitamin C obtained are in line with the pH results obtained.Vitamin C in the flesh of the fruit is easily damaged by O2 due to oxidation.However, the decrease in vitamin C levels on day 15 can be influenced by light, storage, and, heating [14].

Number of damaged fruits
Fingerprint analysis showed that the coating type treatment and storage time and interaction had a significant effect (p>0.05) on the characteristics of Kintamani Siamese Orange.The results of the analysis of the highest number of damaged fruits were obtained from uncoated treatment with a storage life of 10 days and 15 days, which is 70.00%.While the lowest number of damaged fruits was obtained in the treatment of porang nanocoating application, the storage time of 5 days was 20.00.The results of the analysis of the number of damaged fruits of Kintamani Siamese Oranges may be seen in Table 6.The results of research that have been conducted show a difference in the test value of the number of damaged fruits in each treatment with a different shelf life.The development of microorganisms during storage is caused by favorable environmental conditions and the availability of nutrients for the growth of microorganisms which further results in fruit damage.In addition, metabolic processes that continue during storage lead to a decrease in the resistance of fruits to putrefactive microorganisms.During storage, oranges experience a deterioration in quality characterized by damage to the fruit.Deterioration in citrus quality includes changes in aroma, moldy skin surface, rot at the base which causes the texture of the fruit to become soft, and watery [15].

Conclusion
Porang coating type treatment affects the acidity, total dissolved solids, vitamin C, and the amount of damaged fruit.Storage time treatment affects the acidity, total dissolved solids, moisture content, and the amount of damaged fruit.For interactions between treatments affect the acidity, total dissolved solids, and moisture content.The best characteristics of Kintamani Siamese Orange were obtained from the treatment of porang nanocoating application with criteria of fruit weight shrinkage value of 12.47%, acidity (pH) of 4.30, total dissolved solids of 15.77ºBrix, moisture content of 94.21%, vitamin C of 78.55 and the amount of damaged fruit of 20.00% up to 5 days storage.

Table 2 .
The acidity of Kintamani Siamese Oranges

Table 5 .
Vitamin C Siamese Orange Kintamani