Effect of Chitosan-Ascorbic Acid Coatings on the Refrigerated Storage Stability of Fresh-Cut Apples

Abstract

Using natural antimicrobial substances in edible films becomes crucial to extend the shelf-life of fresh-cut fruits due to the consumers' preferences. In this study chitosan and ascorbic acid based film was used to improve the shelf-life of fresh-cut apples. Fresh-cut apple cubes were dipped in water (control), ascorbic acid (1%) or mixtures of chitosan-ascorbic acid in different ratios (1%:1%, 2%:2% or 1%:5%) for 5 min. After draining, fresh-cut apples were packed in sterile polypropylene jars and stored at 5 • C for 14 days. The treatment with chitosan and ascorbic acid suppressed browning, retained flesh firmness and maintained phenolic compounds throughout the storage period. Moreover, the treatment with chitosan-ascorbic acid significantly retarded the microbial growth during storage. Those findings suggested that the best performance was acquired in 1% chitosan and 5% ascorbic acid coating. That coating could be practical and useful to prolonging the chemical and microbial shelf lives of fresh-cut apples during refrigerated storage. Coatings 2019, 9, 503 2 of 12 packaging [8], chemical treatments [9], thermal treatments [10], edible coatings [11-13] and hurdle technologies [12,14]. Among these methods, edible coatings have been recently gained more interest than others in food preservation. Edible films and coatings are natural polymers which control moisture transfer, gas exchange, respiration and oxidative reaction rates during handling, storage and transportation of the fresh produce [15,16]. Carbohydrates, proteins, gums, lipids or starch-based edible films can be used as a coating material for fresh-cut products.Chitosan is a carbohydrate-based biopolymer. It is an amino polysaccharide composed of randomly distributed β-(1-4)-linked D-glucosamine and N-acetyl-d-glucosamine units [17][18][19]. Chitosan based edible films and coatings have great potential in the preservation of fruit and vegetables [20][21][22]. Chitosan and its derivatives have an ability to inhibit the growth of yeasts, molds and bacteria [23][24][25]. However, the application of chitosan is limited due to its insolubility at neutral pH [26]. To overcome this disadvantage and to improve solubility of chitosan, different acids were used to decrease pH values below pH 6 to improve chitosan solubility [16,21,[27][28][29]. Qi et al. 2011 [30] studied the effect of chitosan, ascorbic acid and calcium chloride on fresh-cut fuji apples. They used citric acid to dissolve chitosan and prepared film solutions by adding calcium chloride and ascorbic acid. They have found out that coatings effectively retarded enzymatic browning during storage at 5 • C for 8 days, and apple slices with chitosan-coating maintained firmness with a little loss during storage. In another study, calcium chloride-chitosan coatings and chitosan-ascorbic acid coatings during storage at room temperature for 10 h were investigated [31]. Calcium treatments (calcium chloride or lactate) are broadly studied in preserving the quality of fresh-cut fruit and vegatables. There ar...

Multifunctional Role of Chitosan Edible Coatings on Antioxidant Systems in Fruit Crops: A Review

“…Similarly, Adiletta et al [ 75 ] revealed that fig fruit treated with CS-based coating combined with ascorbic acid (1% w / v ) exhibited higher TP content stored at 4 °C for nine days. Likewise, Özdemir and Gökmen [ 92 ] reported that application of CS and ascorbic acid based coating showed higher content and slower decline of TP content compared with the control by the end of storage in fresh-cut apples.…”

“…In CS-coated litchi, sweet cherry, blueberry, strawberry, longan, and pomegranate fruits have been detected a lower reduction of anthocyanin content compared to uncoated ones probably due to their enzymatic degradation owing to anthocyanase, PPO, and peroxidase (POD) throughout the storage period [ 11 , 45 , 49 , 64 , 66 , 67 , 70 , 78 , 83 , 92 , 97 , 104 , 114 ].…”

Effect of Opuntia ficus-indica Mucilage Edible Coating in Combination with Ascorbic Acid, on Strawberry Fruit Quality during Cold Storage

“…Sogvar et al [11] reported that the application of Aloe vera in combination with AA on strawberry fruit improves the postharvest life by maintaining fruit quality attributes as well as firmness, solid soluble content, titratable acidity, vitamin C, anthocyanin, total phenolic, and total antioxidant activity and reduces decay by suppression of total aerobic mesophilic bacteria, yeasts, and mold growth. Other studies showed that coating with chitosan and ascorbic acid is an effective solution for inhibiting the growth of microorganisms, retarding enzymatic browning reactions, and reducing the weight loss of fresh-cut apples during refrigerated storage [22].…”

Dispersion of chitosan nanoparticles stable over a wide pH range by adsorption of polyglycerol monostearate

“…33,34 Chitosan and AA also exhibited synergistic effects, such as wound healing capability on skin 35 and storage stability of fruits. 36,37 The chitosan colloid prepared in AA solution was found to be stable in over a wide pH range from acidic to alkali conditions and exhibits a high thermal stability. This method may offer versatile ways of chitosan nanoparticle to be used as a carrier for foods, cosmetics, drugs, and so on.…”