Potential waste of local crab carapace (Portunus pelagicus) as a source of chitosan as an active layer that can protect bananas has been studied. The process in this study consists of three stages. The first stage was the isolation of chitin through deproteinization process using 2.0 N NaOH solution with a ratio of 1:6 w/v and demineralization process using 1.5 N HCl solution with a ratio of 1:12 w/v. The second stage is the deacetylation stage using 50% NaOH solution with a ratio of 1:20 w/v. Fourier Transform Infra-Red (FTIR) Spectroscopy is used to determine the degree of deacetylation. The third stage is the banana coating application using chitin solution to determine the shelf life of bananas with variations in levels of 2, 2.5, 3 and 3,5 % w/v by immersion method for one hour. It was found that carapace crab, a part that was underutilized from crab, gave rise to chitin deacetylation with a deacetylation rate of 62.11%; pH 8.9 and water content of 7.677%. Chitosan-based coatings are applied to fresh bananas and are found to increase fruit firmness, and inhibit browning. The results show that chitosan-coated bananas have a longer storage time. The application of chitin deacetylated (chitosan) as fruit banana coater found that higher coater levels extend the shelf life of bananas with the best coater content is 3% b/v. It results in a shelf life of bananas for up to 12 days, this is longer than bananas without chitosan layer which only has a shelf life of four days. Increased coating rates have a positive effect on the shelf life of bananas. This study shows that waste from carapace crabs can be used to form active layers that can preserve fruit.

The technology for extracting chitin from shell and other materials needs to be continuously improved, including its conversion to chitosan. Chitosan is a biocompatible polymer, biodegradable, non-toxic, water-soluble at pH below 6.5, and it has protonated amino groups. The benefits of chitosan in industry, food and medicine make it necessary to fully study an efficient chitosan synthesis method and the results can be applied on an industrial scale. This study examined the effect of ultrasonic-assisted in increasing the degree of deacetylation of chitosan produced from Portunus pelagicus shell waste. The production process of chitosan goes through the stages of deproteination, demineralization and deacetylation. All these steps are ultrasound assisted processes with a frequency of 40 kHz through a digital ultrasonic cleaner. Ultrasonic-assisted chitin and chitosan were examined using FTIR spectrometry. The results showed that the ultrasonic method was able to increase the deacetylation degree of chitin with a value of 68.45±0.11% compared to 62.52±0.08% without ultrasonic. Application of ultrasonic assisted deacetylation gave a deacetylation degree of 85.35 ± 0.20%, higher than without ultrasonic 80.24 ± 0.19%.  Physically, ultrasonic-assisted chitosan is smoother and brighter in color. The ultrasonic-assisted chitosan manufacturing method could increase the deacetylation degree and produce high grade chitosan.

Research on microencapsule formulation and evaluation of ethanol extract by spray drying method was carried out to determine the effect of chitosan addition. It is hoped that from this research, chitosan microcapsule preparations can increase the benefits and stability of the extract. Microcapsule evaluation includes: microcapsule water content test, microcapsule size distribution using a Scanning Electron Microscope (SEM). The microcapsules formed were characterized by antioxidant activity using the 2,2-diphenyl-1-pikrilhidrazil (DPPH) method and total phenol content (folin-ciocalteu method). The results of the morphological evaluation showed that the microcapsules were evenly spherical for all formulas and they had an average moisture content of 4,612 ± 0.02. The anti-oxidant activity of DPPH-SA increased with the increasing concentration of added chitosan. Micro encapsules of the extract without chitosan and with the addition of 0-1% chitosan has antioxidant activity of 85,876 ± 1,897% and 86,014 ±0.570-86,725 ±0.313. In the TPC (Total Phenol Content) test, the results were 5.00 ± 0.01% and 5.49 ± 0.01-8.98 ±0.02%. Based on the research, it could be concluded that the microencapsulation with the addition of chitosan was able to increase the stability of the extract so that the antioxidant activity and total phenolic content could be higher.