This paper investigates the application of visco-hyperelastic model to soft rubberlike material, that is gluten. Gluten is a major protein in wheat flour dough (a mixture of flour and water) which exists as long network fibers and undergo large deformation under uniaxial tension and compression. The visco-hyperelastic model is represented by a combination of the viscoelastic Prony series and the hyperelastic extended tube model. Calibration of the visco-hyperelastic model to gluten tests result suggests that gluten can be modelled as a finite viscoelastic material.
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.
Trace elements play a significant role in giving nutritional benefits to the body because they act as essential cofactors for all physiological processes. However, there are some trace elements which may bring more harm than good when entering the human body. Due to its ability to incorporate trace elements in an amount that is proportional to an individual’s dietary intake and environmental exposure, human fingernails are suitable biomarkers in assessing the health status of an individual as they reflect on the trace element concentration present in the body. This study has analysed fingernail samples of 23 adult females residing in Kuching and Kota Samarahan, Sarawak, Malaysia for four elements, namely Cd, Cu, Pb and Zn. By using flame atomic absorption spectroscopy (FAAS), the mean elemental concentrations found in fingernail samples of research participants were 171.8 ± 33.8 μg/g for Zn, 27.8 ± 14.8 μg/g for Cu and 2.64 ± 0.94 μg/g for Pb. Cd concentrations were not able to be detected as they were below the detection limits. A standard reference material, NIST 1568b Rice Flour was used to verify the methods used in elemental analysis using FAAS. Independent t-test which was used to compare the means of Zn and Cu between vegetarians and non-vegetarians showed no significant differences for both elements. Moreover, correlation analysis showed negative correlations between Cu/Zn pair and Pb/Zn pair, whereas significant positive correlation was obtained for Cu/Pb pair. The overall data from this study showed good agreements with data obtained from studies in other countries. Therefore, the current data in this study represents the latest background elemental concentrations in fingernails of the residents in Kuching and Kota Samarahan, Sarawak.
The influence of variety (Cavendish and Dream), stage of ripeness (green and ripe) and parts (pulp and peel) on antioxidative compounds and antioxidant activity of banana fruit was investigated. The TPC and TFC ranged widely from 75.01 to 685.57 mg GAE/100 g and 39.01 to 389.33 mg CEQ/100 g of dry matter respectively. Cavendish banana flour contained higher TPC and TFC compared to Dream variety. TPC and TFC values of banana peel were higher than those of banana pulp. Also, green banana showed higher TPC and TFC values than those of ripe fruit. Radical scavenging activities (inhibition of DPPH) of the extracts ranged from 26.55 to 52.66%. Although Dream banana peel extracts appeared to have low TPC and TFC, its antioxidant activities were ranked moderate to high. This implies that antioxidative compounds other than phenolics and flavonoids were probably responsible for inhibition of DPPH.
Zero-salted yellow alkaline noodles (YAN) were immersed in solutions of resistant starch HYLON™ VII (HC) or fruit coating Semperfresh™ (SC) containing a range of salt (NaCl) between 10 and 30% (w/v). The objective was to evaluate the effect of salt-coatings on the textural, handling, cooking, and sensory properties of YAN. Increasing salt in the coatings caused a reduction in optimum cooking time, cooking loss and increase in cooking yield. The mechanical and textural parameters, sensory hardness, springiness and overall sensory acceptability of the salt-coated noodles however decreased with increasing salt application. HC-Na10 and SC-Na10 showed the highest textural and mechanical parameters, sensory hardness and springiness. The differences in the parameters were attributed mainly to the water absorption properties of starch that was affected by salt application. Thus, the quality of salt-coated noodles was dependent mainly on the amounts of salt applied in the coatings rather than on the types of coatings used.
Banana peel flour (BPF) prepared from green or ripe Cavendish and Dream banana fruits were assessed for their total starch (TS), digestible starch (DS), resistant starch (RS), total dietary fibre (TDF), soluble dietary fibre (SDF) and insoluble dietary fibre (IDF). Principal component analysis (PCA) identified that only 1 component was responsible for 93.74% of the total variance in the starch and dietary fibre components that differentiated ripe and green banana flours. Cluster analysis (CA) applied to similar data obtained two statistically significant clusters (green and ripe bananas) to indicate difference in behaviours according to the stages of ripeness based on starch and dietary fibre components. We concluded that the starch and dietary fibre components could be used to discriminate between flours prepared from peels obtained from fruits of different ripeness. The results were also suggestive of the potential of green and ripe BPF as functional ingredients in food.
This study evaluated the effects of different flours (tapioca, wheat, sago and potato) on the physicochemical properties of duck sausage. The examined physicochemical properties included proximate composition, cooking yield, color (lightness, redness and yellowness), folding, texture profile (hardness, elasticity, cohesiveness, gumminess and chewiness) and sensory properties. The study found that different flours have no effect on the cooking yield of duck sausage. The tapioca formulation showed a mid-range lightness value, folding score and textural properties. Duck sausages made with wheat flour had higher protein content and lightness value and a harder texture. Sausages made with potato flour had a darker color, the lowest folding scores and a softer texture. The addition of sago flour resulted in a higher folding score, greater elasticity and increased overall acceptability of sausage due to higher scores for texture and juiciness. These results show that the properties of duck sausage are influenced by the type of flour used.
The objective of this study was to evaluate the effects of using tapioca and sago flours with or without egg white powder (EWP) on the physicochemical and sensory properties of duck sausages. There was significant increase (P0.05) in hardness and cohesiveness attributes among all the samples examined but significant differences (P
The objective of this study was to examine the effect of different ratios of fish to tapioca flour on the linear expansion, oil absorption, colour, and crispiness of fish crackers. Four different ratios of fish to tapioca flour were used in the formulation of the fish crackers. The results showed that protein and fat content increased with the increase in the ratio of the fish. On the other hand, linear expansion and oil absorption decreased with an increase in the ratio of the fish. Hardness also increased with the increase in the ratio of the fish. The colour measurement showed that the lightness value decreased with an increase in the ratio of fish and this decrease is seen more clearly with the fried fish crackers.
Mushroom cultivation has been more popular recently in Malaysia. They are favoured due to their delicious flavour and low calorific value. Apart from that, they also contain high amount of protein and other essential nutrients. As recommended by food pyramid, people should take in more of their calories from whole grains-based foods than any other sources. Three selected carbohydrate based products namely rice-porridge (RP), paratha flat bread (PB) and conventional cake (CC) were formulated with dried Pleurotus sajor-caju (PSC) powder. All three products were analyzed for proximate analysis and sensory evaluation. Result shows the percentage of moisture, ash, fat and protein of RP increased in line with the levels of PSC powder used except for carbohydrate. Whereas for PB and CCs added with 2%, 4% and 6% PSC, the percentage of all nutrients were higher than control (0%) except for fat. Mushroombased RP had significantly higher value of odour attribute as compared to control, with RP added with 6% PSC powder received the highest score. Meanwhile, mushroom-based PB received better score on textural attribute compared the control. In CC, panels prefer the cake added with 4% PSC powder as they gave higher scores for softness and flavour attributes. In conclusion, addition of PSC powder to partially replace rice and wheat flour in RP, CC and PB enhance essential nutritional components and well accepted by consumers. Thus, PSC powder can be considered to be utilized in carbohydrate–based food products with the purpose of enhancing nutrient compositions without affecting its sensory acceptance.
This work aimed to evaluate the effect of Atmospheric Cold Plasma (ACP) on the quality of mango flour noodles (NMF). ACP treatment of 5 minutes duration on the surface of the noodles strands were performed and evaluated during three days of storage by monitoring parameters related to colour, water activity, antioxidant activity and total phenolic content. The lightness value (L*) was higher for untreated samples (NMF (U)) than for treated samples (NMF (T)), while a greater increased in the redness (a*) and yellowness (b*) values were observed for the NMF (T). The changes in aw, antioxidant activity and total phenolic content (TPC) were negligible. However the NMF (T) showed significant different (p
Pumpkin products confer natural sweetness, desirable flavours and β-carotene, a vitamin A precursor when added as ingredients to extruded snacks. Therefore, a potential use for dried pumpkin flour is as an ingredient in ready-to-eat (RTE) snack foods. Growth in this market has driven food manufacturers to produce a variety of new high value snack foods incorporating diverse ingredients to enhance the appearance and nutritional properties of these foods. Ready-to-eat snacks were made by extruding corn grits with 5%, 10%, 15% and 20% of pumpkin flour. Snacks made from 100% corn grits were used as control products for this work. The effect of formulation and screw speeds of 250 rpm and 350 rpm on torque and specific mechanical energy (SME, kWh/kg), physical characteristics (expansion ratio, bulk density, true density and hardness) and the microstructure of the snacks were studied. Increasing the screw speed resulted in a decrease of torque for all formulations. When pumpkin flour was added the specific mechanical energy (SME) decreased by approximately 45%. Increasing the percentage of pumpkin flour at the higher screw speed resulted in a harder texture for the extruded products. X-ray tomography of pumpkin flour-corn grit snacks showed that increased levels of pumpkin flour decreased both the bubble area and bubble size. However, no significant differences (p > 0.05) in bubble wall thickness were measured. By understanding the conditions during extrusion, desirable nutritional characteristics can be incorporated while maximizing expansion to make a product with low bulk density, a fine bubble structure and acceptable organoleptic properties.
This study examined the physicochemical properties of rice flours with five different particle sizes (≤63, 80, 100, 125, and 140 μm) prepared by dry milling and their effects on textural properties of laksa noodles. Rice flour with the smallest particle size had the highest water absorption index, peak viscosity, hot paste viscosity, breakdown, final or cold paste viscosity and gel hardness, but the lowest gelatinization temperature. Reduction of rice flour particle size improved textural properties of laksa noodle. Laksa noodle produced from rice flour with the smallest particle size had the best textural properties.
The textural and sensorial properties of the cookies prepared by partial substitution of wheat flour with two types of unripe banana flour (UBF) were studied. The green matured unripe banana (Musa x paradisiaca var. Tanduk and Musa acuminata var. Emas) was used to partially substitute the usage of wheat flour at 0% (control), 25% and 50% level in the formulated plain cookies. Textural (hardness) and sensorial properties were conducted on all samples. Substitution of UBF to formulation of cookies had increased the hardness of cookies (ranging from 967 N to 1665 N) compared to the control except for substitution of Emas banana flour (EBF) at 50% which was not significantly difference (p > 0.05) with control sample. The substitution of 25% of Tanduk banana flour (TBF) showed the highest mean score in overall acceptability (6.81 ± 1.18) compared to all treated samples. TBF substitution is feasible up to 50% substitution while for EBF, the substitution only up to 25% level in this study.
This study investigated the influence of pregelatinized high-amylose maize starch and chilling treatment on the physical and textural properties of canned rice noodles thermally processed in a retort. Rice noodles were prepared from rice flour partially substituted with pregelatinized high-amylose maize starch (Hylon VII™) in the ratios 0, 5, 10, and 15% (wt/wt). High-amylose maize starch improved the texture and brightness of fresh (not retorted) noodles. Chilling treatment led to significant (P ≤ 0.05) improvement in the texture of fresh noodles at all levels of substitution with high-amylose starch. The highest hardness was recorded at 15% amylose level in chilled nonretorted noodles. Retort processing induced a major loss of quality through water absorption, retort cooking loss, decreased noodle hardness, and lightness. However, the results showed that amylose and chilling treatment positively reduced the impact of retorting. For each level of amylose substitution, a low retort cooking loss and increased noodle hardness were associated with a chilling treatment. For both chilled and nonchilled noodles, retort cooking loss and hardness increased with increasing levels of amylose substitution.
Biscuit is a popular food product where it is produced using wheat flour, sugar and fat as its main ingredients. Wheat flour is the major material used in biscuit production and within the flour starch is the principal component. The details of starch properties such as pasting properties, gelatinisation properties, crystallinity were discussed in this review. Starch is the major structural element in many foods, with the fat or sugar also playing key roles. Sugar gives sweetness, colour, add volumes and influence the texture of a biscuit. Besides that, it shows significant impact on starch gelatinization properties. Fat plays an important role in biscuit production and the type of fat used determines the quality of the final product. In this article, the functional properties of major ingredients of biscuit were also reviewed with emphasis on wheat flour, sugar and fat.
Adzuki bean is high in protein and fiber with a potential to be used as meat extender and fat replacer in the meat product. Replacement of both the corn flour and fat with different percentages of adzuki beans flour (ABF) has successfully produced acceptable reduced fat meatballs. Meatballs with 100% (w/w) ABF replacement exhibited highest cooking yield and higher moisture content compared to meatballs without the flour, which indicates its ability to bind water. Increasing the ABF content also increased the hardness and chewiness of the meatballs, whilst decreasing their lightness and yellowness. Replacing the corn flour and fat contents with ABF has obviously decreased the fat and calorie contents of the meatballs, yet their protein and carbohydrate contents remained the same compared to control. The sensory test revealed that meatball samples with 25% (w/w) and 50% (w/w) ABF showed no significant difference compared to control but received highest overall acceptability among the panelists. This indicates that replacement of corn flour and fat with ABF especially at 50% (w/w) in the production of reduced fat meatballs resulted with better physicochemical properties and acceptable sensory compared to original meatballs.
The present study was conducted to evaluate the antioxidant properties of wheat and rice flours under simulated gastrointestinal pH condition. After subjecting the wheat and rice flour slurries to simulated gastrointestinal pH condition, both slurries were centrifuged to obtain the crude phenolic extracts for further analyses. Extraction yield, total contents of phenolic and flavonoids were determined as such (untreated) and under simulated gastrointestinal pH condition (treated). 1,1-diphenyl-2-picrylhydrazyl radical (DPPH(•)) scavenging activity, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical cation (ABTS(•+)) scavenging activity, ferric reducing antioxidant power (FRAP), beta-carotene bleaching (BCB) and iron chelating activity assays were employed for the determination of antioxidant activity of the tested samples. In almost all of the assays performed, significant improvements in antioxidant properties (p < 0.05) were observed in both flours after treatment, suggesting that wheat and rice flours contain considerably heavy amounts of bound phenolics, and that their antioxidant properties might be improved under gastrointestinal digestive conditions.
The importance and development of industrial biotechnology processing has led to the utilisation of microbial enzymes in various applications. One of the important enzymes is amylase, which hydrolyses starch to glucose. In Malaysia, the use of sago starch has been increasing, and it is presently being used for the production of glucose. Sago starch represents an alternative cheap carbon source for fermentation processes that is attractive out of both economic and geographical considerations. Production of fermentable sugars from the hydrolysis of starches is normally carried out by an enzymatic processes that involves two reaction steps, liquefaction and saccharification, each of which has different temperature and pH optima with respect to the maximum reaction rate. This method of starch hydrolysis requires the use of an expensive temperature control system and a complex mixing device. Our laboratory has investigated the possibility of using amylolytic enzyme-producing microorganisms in the continuous single-step biological hydrolysis of sago flour for the production of a generic fermentation medium. The ability of a novel DNA-recombinated yeast, Saccharomyces cerevisiae strain YKU 107 (expressing alpha-amylase production) to hydrolyse gelatinised sago starch production has been studied with the aim of further utilizing sago starch to obtain value-added products.
This research was conducted to investigate the effects of different grinding techniques (dry, semi-wet and wet) of milled rice grains on the damaged starch and particle size distribution of flour produced from a new variety, MR263, specifically related to the pasting and thermal profiles. The results indicated that grinding techniques significantly (p<0.05) affected starch damage content and particle size distribution of rice flour. Wet grinding process yields flour with lowest percentage of starch damage (7.37%) and finest average particle size (8.52μm). Pasting and gelatinization temperature was found in the range of 84.45-89.63°C and 59.86-75.31°C, respectively. Dry ground flour attained the lowest pasting and gelatinization temperature as shown by the thermal and pasting profiles. Correlation analysis revealed that percentage of damaged starch granules had a significant, negative relationship with pasting temperature while average particle size distribution had a significant, strong negative relationship with gelatinization temperature.