Emma Rochima

Amino Acid Profile and Volatile Flavour Compounds of Raw and Steamed Patin Catfish (Pangasius hypophthalmus) and Narrow-barred Spanish Mackerel (Scomberomorus commerson)

Fish species and processing methods could affect the volatile flavour composition and amino acid profile of fishery commodity. The objectives of this study were to identify volatile components and amino acid profile of two considered predominant fish species in Indonesia which are freshwater Patin catfish (Pangasius hypophthalmus) and marine water fish, Spanish mackerel (Scomberomorus commerson). The methods used in this study were to detect volatile compounds using Gas Chromatography/Mass Spectrometry (GC/MS) on fresh and steamed of both species samples (100°C for 30 minutes) and amino acid profile were also analyzed using High Performance Liquid Chromatography (HPLC). The volatile components analysis successfully detects as much as 29 and 59 volatiles compounds in fresh and steamed Patin catfish respectively, while 37 and 102 compounds were detected in fresh and steamed Spanish mackerel samples. Most of detected components derives from hydrocarbons, aldehydes, alcohols and ketone groups which could affected by their chemical composition and resulted from various thermal involved reaction. The amino acids profile identification results showed that glutamic acid was found higher compared to other amino acids standards in both samples. Glutamic acid is non-essential amino acid which is important in umami taste substances.

UV-screening, transparency and water barrier properties of semi refined iota carrageenan packaging film incorporated with ZnO nanoparticles

This study aims to develop film for food packaging application with high UV-screening, transparency and water barrier properties. Semi refined iota carrageenan (SRiC) nanocomposite films prepared by addition of zinc oxide (ZnO) nanoparticles as nanofiller using solution casting method. The effect of nanofiller with different concentration (0%, 0.5%, 1.0%, 1.5% w/w carrageenan) on UV-screening, transparency and water barrier properties of films were tested. The water barrier properties of the films were studied by measuring water vapor permeability (WVP) and the optical properties of the films were studied by using UV-Vis spectrophotometer at 280 nm for UV-screening test and at 660 nm for transparency test. WVP value of carrageenan films with addition of ZnO is low compared to a control carrageenan film and the lowest WVP value was found for the film with addition of 1.5% of ZnO. These result indicate that the addition of ZnO had a positive effect on the water barrier properties of the carrageenan matrix. Increase in the concentration of nanofiller leads to an increase in the UV-screening properties. Among all the films, carrageenan film with 1.5% ZnO has the highest UV-screening. The result showed that adding 0.5% and 1.0% of ZnO was insignificantly affect transparency of the films, however the transparency decreased sligthly when 1.5% ZnO was added. In conclusion, incorporating no more than 1.0% of ZnO to the films can obtain films with high UV-screening, transparency and water barrier properties and suitable for food packaging application.This study aims to develop film for food packaging application with high UV-screening, transparency and water barrier properties. Semi refined iota carrageenan (SRiC) nanocomposite films prepared by addition of zinc oxide (ZnO) nanoparticles as nanofiller using solution casting method. The effect of nanofiller with different concentration (0%, 0.5%, 1.0%, 1.5% w/w carrageenan) on UV-screening, transparency and water barrier properties of films were tested. The water barrier properties of the films were studied by measuring water vapor permeability (WVP) and the optical properties of the films were studied by using UV-Vis spectrophotometer at 280 nm for UV-screening test and at 660 nm for transparency test. WVP value of carrageenan films with addition of ZnO is low compared to a control carrageenan film and the lowest WVP value was found for the film with addition of 1.5% of ZnO. These result indicate that the addition of ZnO had a positive effect on the water barrier properties of the carrageenan matrix. ...

The dispersion of fine chitosan particles by beads-milling

This research aimed to produce fine chitosan particles from a crab shell waste by beads-milling method by two different concentration of PEG as dispersing agent (150 and 300 wt. %). The characterization was performed to obtain the size and size distribution, the characteristics of functional groups and the degree of deacetylation. The results showed that the chitosan fine particles was obtained with a milling time 120 minutes with the best concentration of PEG 400 150 wt. %. The average particle size of the as-prepared suspension is 584 nm after addition of acetic acid solution (1%, v/v). Beads milling process did not change the glucosamine and N-acetylglucosamine content on chitosan structure which is indicated by degree of deacetylation higher than 70%. It was concluded that beads milling process can be applied to prepare chitosan fineparticles by proper adjustment in the milling time, pH and dosage of dispersing agent.

The addition of nanochitosan suspension as filler in carrageenan-tapioca biocomposite film

This research aimed to investigate the effect of nanochitosan (CSNPs) suspension by beads milling method as filler in carrageenan-tapioca biocomposite film. In addition, the antibacterial activity of CSNPs as filler with two food pathogenic bacteria, Staphylococcus aureus and Escherichia coli and then influence of nano fillers for appearance of films were observed. The incorporation of CSNPs suspension with 0.5, 1, 1.5 and 2 (%v/v) in carrageenan-tapioca film exhibited antibacterial activity againts both bacteria. CSNPs had slightly higher antimicrobial activity against E. coli aureus compared to S. aureus at all concentrations due to different mechanisms. Therefore, the best antimicrobial activity was obtained from 1 wt%. Furthermore the best antimicrobial activity was characterized by means of the thickness and transparency. The result showed that the thickness of film was 0.059 mm and the transparency was 87.88. It was concluded that the incorporation of CSNPs suspension 1 wt% in carrageenan-tapioca composite film is suitable for developing active packaging.This research aimed to investigate the effect of nanochitosan (CSNPs) suspension by beads milling method as filler in carrageenan-tapioca biocomposite film. In addition, the antibacterial activity of CSNPs as filler with two food pathogenic bacteria, Staphylococcus aureus and Escherichia coli and then influence of nano fillers for appearance of films were observed. The incorporation of CSNPs suspension with 0.5, 1, 1.5 and 2 (%v/v) in carrageenan-tapioca film exhibited antibacterial activity againts both bacteria. CSNPs had slightly higher antimicrobial activity against E. coli aureus compared to S. aureus at all concentrations due to different mechanisms. Therefore, the best antimicrobial activity was obtained from 1 wt%. Furthermore the best antimicrobial activity was characterized by means of the thickness and transparency. The result showed that the thickness of film was 0.059 mm and the transparency was 87.88. It was concluded that the incorporation of CSNPs suspension 1 wt% in carrageenan-tapioca co...

Development and performance evaluation of air fine bubbles on water quality of thai catfish rearing

The efficiency and productivity of aquaculture strongly depends on the development of advanced technology for water quality management system. The most important factor for the success of intensive aquaculture system is controlling the water quality of fish rearing media. This paper reports the design of fine bubbles (FBs) generator and performance evaluation of the system to improve water quality in thai catfish media (10 g/ind) with density (16.66 ind./L). The FBs generator was designed to control the size distribution of bubble by controlling its air flow rate entry to the mixing chamber of the generator. The performance of the system was evaluated based on the produced debit, dissolved oxygen rate and ammonia content in the catfish medium. The size distribution was observed by using a high speed camera image followed by processing using ImageJ. freeware application. The results show that air flow rate 0.05 L/min and 0.1 L/min received average bubble size of 29 µm and 31 µm respectively. The generator produced bubbles with capacity of 6 L/min and dissolved oxygen rate 0.2 ppm/min/L. The obtained DO growth was 0.455 ppm/second/L while the average decay rate was 0.20 ppm/second/L. (0.011/0.005 fold). In contrast, the recieved DO growth rate is faster compared to the DO consumption rate of the Thai catfish. This results indicated that the potential application of FBs enhanced the density of thai catfish seed rearing. In addition, ammonia can be reduced at 0.0358 ppm/hour/L and it is also observed that the inhibition of bacterial growth of air FBs is postive to Aeromonas hydrophila bacteria compared to the negative control. It is concluded that as-developed FBs system can be potentially applied for intensive thai catfish culture and expected to improve the feeding efficiency rate.

Mechanical and solubility properties of bio-nanocomposite film of semi refined kappa carrageenan/ZnO nanoparticles

The aim of this present work is to develop semi refined kappa carrageenan based bio-nanocomposite film as an alternative to synthetic petroleum based food packaging materials. Among natural polymers, carrageenan is one of the most promising material, since it is a renewable bioresource. The ZnO nanoparticles (0.5%; 1.0%; 1.5% w/w carrageenan) was incorporated into carrageenan polymer to prepare bio-nanocomposite films, where ZnO acts as reinforcement for carrageenan matrix. The mechanical and solubility properties of the prepared films were investigated as a function of ZnO concentration. The results indicated that the addition of ZnO exhibits greater solubility compared to the neat film. The elongation at break is insignificantly different on the films with and without addition ZnO. The tensile strength of the film was highest for the sample with 0.5% ZnO. These mechanical and solubility properties suggest that bio-nanocomposite film of semi refined kappa carrageenan and nanoparticle ZnO can be effective...

Optical transparency and mechanical properties of semi-refined iota carrageenan film reinforced with SiO2 as food packaging material

Food packaging is important for protecting food from environmental influences such as heat, light, water vapor, oxygen, dirt, dust particles, gas emissions and so on, which leads to decrease the quality of food. The most widely used type of packaging in the food industry is plastic which is made from synthetic polymers and takes hundreds of years to biodegrade. Recently, food packaging with high bio-degradability is being developed using biopolymer combined with nanoparticles as reinforcing agent (filler) to improve its properties. In this study, semi-refined iota carrageenan films were prepared by incorporating SiO2 nanoparticles as filler at different concentrations (0%, 0.5%, 1.0% and 1.5% w/w carrageenan) using solution casting method. The optical transparency and mechanical properties (tensile strength and elongation at break) of the films were analyzed. The results showed that incorporation of SiO2 nanoparticles to carrageenan matrix on optical transparency of the films. For the mechanical propertie...