Synthetic plastics are severely detrimental to the environment because non-biodegradable plastics do not degrade for hundreds of years. Nowadays, these plastics are very commonly used for food packaging. To overcome this problem, food packaging materials should be substituted with "green" or environmentally friendly materials, normally in the form of natural fiber reinforced biopolymer composites. Thermoplastic starch (TPS), polylactic acid (PLA) and polybutylene succinate (PBS) were chosen for the substitution, because of their availability, biodegradability, and good food contact properties. Plasticizer (glycerol) was used to modify the starch, such as TPS under a heating condition, which improved its processability. TPS films are sensitive to moisture and their mechanical properties are generally not suitable for food packaging if used alone, while PLA and PBS have a low oxygen barrier but good mechanical properties and processability. In general, TPS, PLA, and PBS need to be modified for food packaging requirements. Natural fibers are often incorporated as reinforcements into TPS, PLA, and PBS to overcome their weaknesses. Natural fibers are normally used in the form of fibers, fillers, celluloses, and nanocelluloses, but the focus of this paper is on nanocellulose. Nanocellulose reinforced polymer composites demonstrate an improvement in mechanical, barrier, and thermal properties. The addition of compatibilizer as a coupling agent promotes a fine dispersion of nanocelluloses in polymer. Additionally, nanocellulose and TPS are also mixed with PLA and PBS because they are costly, despite having commendable properties. Starch and natural fibers are utilized as fillers because they are abundant, cheap and biodegradable.
The quality change of fish sausage (keropok lekor) coated in sago starch-gelatine coating with
papaya seed extract (PSE) during chill storage (7°C) was determined. During storage, pH,
thiobarbituric acid value (TBA), colour, moisture, and the total plate count were evaluated. pH
of samples significantly dropped (p < 0.05) during storage, and the highest decrease was in
control sample. The moisture content in control sample had an increasing trend while that of
samples with 5 and 7% PSE coatings significantly decreased, and only a slight change for
samples with 0% PSE coating. All samples had significant increase in their TBA values during
storage. The presence of the coating provided a positive effect on the colour of the fish sausages since no significant colour changes were observed during storage. TPC of control and
coated sausage in 0, 5, and 7% PSE exceeded the recommended microbial standard after 2, 6,
8, and 4 d of storage, respectively. Overall, coating with 5% of PSE was the most effective in
retarding the quality deterioration of the fish sausages.
Nowadays, functional food market is dominated by dairy-based probiotic products, mainly
yogurt. The nutritional values of yogurt can be further enhanced by the inclusion of miracle
fruit (Synsepalum dulcificum) and potential probiotic Lactococcus lactis Gh1. The present
work investigated the anti-oxidative capacity and survivability of probiotic strains of six
yogurts fortified with S. dulcificum pulp extract and encapsulated L. lactis Gh1 (in
alginate-starch coating agent via extrusion technique). The flavonoid contents (TFC) were not
significantly different between yogurts, whereas the phenolic contents (TPC) showed an
increasing trend throughout the storage. Among the yogurts, the one supplemented with both
S. dulcificum and encapsulated L. lactis Gh1 showed the highest TFC (1.18 µg QE/mL) and
TPC (15.382 μg GAE/mL). The antioxidant assay (DPPH) showed a gradual increase on the
first 7 d, but decreased afterward. In comparison, yogurts fortified with S. dulcificum demonstrated higher antioxidant activity (± 80% DPPH inhibition) than the plain yogurts (± 50%
DPPH inhibition). The viability of starter cultures (Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus) drastically increased during the first week (log 8 ~ 10
CFU/mL) especially for yogurts containing free cell L. lactis, but subsequently decreased ( log
6 ~ 8 CFU/mL). The viability of L. lactis Gh1 in yogurts maintained at high count (log 9.43
and 9.04 CFU/mL) throughout 21 d when it was being encapsulated. In general, the fortification of S. dulcificum extract with microencapsulated L. lactis Gh1 had greatly enhanced the
quality and potential benefits of the functional yogurts.
The aim of the present work was to develop chicken skin gelatin films incorporated with
different concentrations of rice starch prepared by casting techniques. Six film-forming
solutions were prepared separately with different blend ratios of chicken skin gelatin to rice
starch: A (0/100), B (5/100), C (10/100), D (15/100), E (20/100), and F (25/100). The
rheological properties of the film-forming solutions (FFS) were determined using frequency
sweep. The mechanical and physical properties of the respective films were also evaluated.
With the increase in rice starch concentration, the storage (G’) modulus of FFS increased
dramatically with loss (G”) modulus as the oscillatory frequency rising to contribute to gel
behaviour (G’ > G”). As rice starch concentration increased, the chicken skin gelatin films
also demonstrated higher tensile strength, elongation at break, and water vapour permeability,
but reduced the solubility of gelatin films in water. Additionally, elevation in melting point
values indicated that the thermal stability of the composite films was enhanced with the
increment of rice starch concentration. Film F (with 25% rice starch) yielded the optimal film
formulation, as it had the highest tensile strength and a high elongation at break value. Thus,
film F shows the best potential as a film for food packaging.
Banana pulp (BP) noodles prepared by partial substitution of wheat flour with green Cavendish banana pulp flour were assessed pH, color, tensile strength and elasticity, and in-vitro hydrolysis index (HI) and estimated glycemic index (GI). BP noodles had lower L* (darker) and b* values (less yellow) but higher tensile strength and elasticity modulus than control noodles. Following an in-vitro starch hydrolysis studies, it was found that GI of BP noodles was lower than control noodles. Partial substitution of green banana pulp into noodles may be useful for controlling starch hydrolysis of yellow noodles.
Changes to the physicochemical properties of wheat, sago and tapioca starches subjected to gamma ray, electron beam and microwave irradiations and the conditions that lead to wheat starch having leaching behaviour similar to sago or tapioca starch were studied. The properties were characterised through swelling and leaching behaviours of the starch granules and retrogradation following pasting. The leaching of wheat starch increased tremendously and resulted in amylose to amylopectin ratios in the leachate similar to that of native sago and tapioca starches. This observation is significant as wheat starch is known to have a leachate composition of mostly amylose. This opens up the possibility of utilising wheat starch in snacks where tapioca and sago starch are commonly used. It was observed that the required conditions for such changes were exposure to microwave for 8 and 10 minutes, electron beam at 5 and 10 kGy and gamma ray at 5 kGy.
The banana pseudo-stem is not currently utilised in the food industry. The aim of this research was to investigate the chemical and pasting profile of banana pseudo-stem flour (BPF). Wheat flour were substituted with BPF (0, 5, 15 and 30%) and the pasting profile were determined. Results from mineral analysis showed that the levels of sodium (Na), potassium (K), calcium (Ca), magnesium (Mg) and phosphorus (P) were higher than those of iron (Fe), zinc (Zn) and manganese (Mn). The BPF had a 0.04% total titratable acidity (TTA) and a total soluble solid (TSS) of 1.30⁰ Brix with pH 5.41. BPF contained 28.26% total starch, 12.81% resistant starch and a total digestible starch value of 15.45%. An increased substitution level of BPF into wheat flour significantly (p
The impacts on both rheological parameters; Casson yield stress and Casson viscosity were determined. The interactions among blend’s components; xanthan gum (XG), corn starch (CS), glycerin (GL) and their relationship with both flow parameters were also investigated by using D-Optimal mixture design. Three levels of cocoa butter substitution assigned in chocolate production were at 5%, 10% and 15% level with random proportions of each component generated by Design Expert software. An appropriate mathematical model was applied to evaluate each response as a function of the proportions of the components enabling in prediction of future response by using any blend of components. As the incorporation of the blends (XG/CS/GL) in chocolate production was elevated from 5% to 15%, both parameters; viscosity and yield stress of chocolate were gradually increased, as in range 7.819 to 10.529 Pa, and 2.372 to 3.727 Pa.s, respectively. Neither binary nor ternary component-component interaction exhibited synergistic effect. Nevertheless, strongest antagonistic effect on both rheological parameters of substituted chocolate at 5% level and 10% level were respectively observed at ternary interaction region for the former, and at binary interaction area of CS:GL, closer to CS corner as for the latter. This study somehow provides ideas on how component-component interactions influence experimented response.
The effects of orange sweet potato flour addition to tapioca starch on the expansion, oil absorption,
bulk density, water absorption index (WAI), water solubility index (WSI), hardness and colour of fried extruded fish crackers were investigated. The microstructure properties were assessed by Field Emission Scanning Electron Microscope (FESEM) and the sensory properties of fried extruded fish crackers were determined by quantitative descriptive analysis method. The shape and texture of the product were similar to that of normal breakfast cereal. Light brownish and slightly harder texture was obtained with addition of orange sweet potato flour to tapioca starch in the fried extruded fish crackers. The bulk density and water solubility index (WSI) increased with the increase in orange sweet potato flour addition. However, water absorption index (WAI), linear expansion, expansion ratio, volume expansion and oil absorption decreased as the amount of orange sweet potato increased. The microstructure studies revealed that fried extruded fish crackers with high percentage of orange sweet potato flour had small air cells and thick cell wall. The fried extruded fish crackers with 30% fish, 14% orange sweet potato flour and 56% tapioca starch had high crispiness score and accepted by the trained panellists.
Starch is a biodegradable polymer produced in abundance from many renewable resources. This study examined the influence of citric acid (0-40% w/wt%) ) and water (0-40% w/wt%) as secondary additive and glycerol as plasticizer on the mechanical properties of bio-plastic starch (BPS) from Malaysian sago. The CA content varies from 0 to 40 w/wt% while water was also varied from 0 to 40 w/wt%. FT-IR spectroscopy showed that acid citric improve the properties of BPS and water give negative effects to the carbon hydrogenbond. It is obvious that the addition of the CA at 30 wt/wt% improve the mechanical property of BPS to more than 40% compare to the addition of water.
Quality attributes of steamed bread without green banana flour (BF) (CON), substituted with 30%
BF (BBFI) and 30% BF + 8% gluten (BBFII) were determined. The green banana flour (BF) and the mixture of wheat flour (WF) substituted with 30% BF + 8% gluten (FBFII) was significantly highest in water holding capacity and oil holding capacities, respectively. Potassium, calcium and magnesium were significantly higher in BBFI and BBFII than CON. Significantly highest insoluble dietary fibre and total dietary fibre shown in BBFI. Steaming resulted significant reduction in resistant starch content in BBFI as compared with the dough of BBFI I. The specific volume of BBFII and CON showed significant different compared to the BBFI. The BBFII spread ratio was significantly highest and steamer spring lowest than CON. BBFII showed significantly highest in hardness and adhesiveness values but CON was significantly highest in cohesiveness, elasticity and chewiness. L and Hue values was shown highest in CON. BBFII indicated highest acceptability score than other samples.
The aim of this study was to determine the specific content and type of sugars in selected commercial and traditional kuih in Klang Valley. The selection of the kuih was based on the validated Food Frequency Questionnaire (FFQ) for sugar. The selected commercial kuih was doughnut coated with sugar (Big Apple) while the ten traditional kuih samples consisted of kuih bingka ubi, kuih kasui, kuih keria, kuih koci, kuih lapis, kuih lopes, kuih onde-onde, kuih sagu, kuih seri muka and kuih talam. The doughnut coated with sugar (Big Apple) was purchased from Big Apple Donuts and Coffee franchise at two different locations, while the traditional kuih were randomly bought from stalls, cafeterias and restaurants around Kuala Lumpur and Rawang. The types and amount of sugar were determined using High Performance High Chromatography (HPLC) with a refractive index (RI) detector. Results showed that doughnut coated with sugar (Big Apple) has the highest starch content (22.6±0.3 g/100g) and kuih keria contained the highest available carbohydrate (41.5±1.7 g/100g), comprising of 24.2±2.4 g/100g total sugar and 17.3±0.7 g/100g of starch. The least available carbohydrate content was found in kuih talam (20.0±0.5 g/100g), which was 50% lower than the one in kuih keria. Major individual sugars detected in all kuih samples were consisted of sucrose (60.0%), glucose (16.2%), fructose (14.0%), maltose (9.5%) and lactose (0.3%). Majority of the kuih samples (90.9%) in this study can be categorized as medium sugar while only kuih keria was categorized as high sugar. Based on the two main ingredients (sugar and flour) used in the preparation of kuih, results showed that all kuih samples can be categorized as medium sugarmedium starch. In conclusion, this study served as a guideline by locals in selecting kuih of
different sugar levels.
This study was carried out to determine the proximate, functional and pasting properties of breadfruit starch. Breadfruit starch was isolated from matured breadfruit (Artocarpus altilis) and was analyzed for its fuctional, proximate and pasting properties. The starch contains 10.83%, 0.53%, 0.39%, 22.52%, 77.48% and 1.77% moisture, crude protein, fat, amylose, amylopectin and ash contents respectively. The average particle size, pH, bulk density and dispersibility of the breadfruit starch were 18 μm, 6.5, 0.673 g/mls, and 40.67% respectively. The swelling power of the breadfruit starch increases with increase in temperature, but there was a rapid increase in the swelling power from 70 to 80 0C. The pasting temperature of the starch paste was 84.05 0C, setback and breakdown values were 40.08 and 7.92 RVU respectively. The peak viscosity value was 121.25 RVU while final viscosity value was 153.42 RVU. This study concluded that breadfruit starch has an array of functional, pasting and proximate properties that can facilitate its use in so many areas where the properties of other starches are acceptable.
In this study, acid-thinned starch was blended with konjac glucomannan or psyllium husk powder at a concentration of 3% w/w (starch basis). The blends were characterized by pasting analysis and rheological
properties evaluation. Jelly candy was made from the blends and textural characteristics were studied. Pasting analysis showed that both gums were found to significantly increase some of the pasting parameters, such as peak viscosity, trough, breakdown, final viscosity and setback values. From the frequency sweep, it was found that addition of konjac glucomanan or psyllium husk powder increased the storage modulus (G’) and loss modulus (G’’) values, with psyllium added sample showing more prominent effect than konjac added ones, when compared to the control samples. All samples were found to demonstrate thixotropic flow behaviour. Jelly candy texture profile analysis revealed that konjac glucomannan or psyllium husk powder addition, although decreasing chewability, but rendered the jelly candy less sticky.
Changes in the physicochemical properties of wheat, sago, tapioca and potato starches were studied
after heating for 1 hour at 100oC, 110oC, and 120oC and for 2 hours at 120oC. These properties were characterised through the swelling behaviour of starch granules, amount of carbohydrate materials leached from the granules, starch paste retrogradation rate and gel strength. For all starches except wheat, the swelling ability, rate of retrogradation and gel strength decreased while solubility increased with increasing temperature and heating time. Wheat starch followed this pattern only when heated at 120oC for 1 and 2 hours. Gel strength correlated well with the ratio of amylose to amylopectin (R) in the leachate. To produce fried crackers with good expansion properties, the granule has to be sufficiently degraded so as to allow more amylopectin to be leached out to achieve R value of 0.25-0.5. This can be achieved by heating wheat starch at 120oC for 1 hour or longer.