Ozone dose from 0.1 to 0.4 ppm has been proven to be effective in lowering Bacillus cereus count in uncooked and cooked rice. However, it induces physicochemical changes in raw white rice. Physicochemical tests were done to see the effect of ozone treatment towards moisture content, pH, color, hardness of uncooked rice, adhesiveness and hardness of cooked rice, cooking quality and total solids. Results have shown that moisture content, adhesiveness and hardness of cooked rice and uncooked rice have not undergone any significant changes (P > 0.05) in comparison with controlled rice sample. Meanwhile, color (L* and b* value), pH, total solids and cooking quality results have shown significant changes (P
Herein we examine the characteristics of date seed oil extracted from Chamaerops humilis L. var. humilis seeds (HSO) cultivated in a gardening zone in Tunisia. Its physicochemical properties, fatty acid composition, and thermal and antioxidant properties were evaluated and compared with those of seed oil from another variety of Chamaerops humilis. The results showed that HSO possessed higher contents of oleic (44%) and linoleic (20%) acids than the other seed oil. The total tocopherol and tocotrienol content was 88 mg/100 g oil, where α-tocotrienol (64%) was the major isomer. The total phenolic (91 μg/g oil) and flavonoid contents (18 μg/g oil) of the HSO were determined, and its antioxidant capacities, measured in terms of ABTS and DPPH radical-scavenging capacities, were 210 µM TEAC/g DW and 4.3 mM TEAC/g DW, respectively. The oxidative stability index (OSI) of the oil was 16 h at 110 °C. Furthermore, the OSI of soybean oil was significantly enhanced upon blending with HSO. HSO exhibited higher thermal stability than the other oils and significantly different thermal behavior. The determination of fatty acid composition, physicochemical properties, bioactive content, oxidative stability, and thermal behavior of HSO demonstrated that this renewable resource can be used for edible purposes.
Fresh food products are highly prone to oxidation and microbial attack, rendering them unsuitable for consumption. Thus, active food packaging was developed to protect and prolong food shelf-life. Zein/gellan gum (GG) based active film is developed by incorporating rosemary oleoresin extract (ROE) (0-20%). The films were characterized by their barrier and antioxidant properties. The release behavior of ROE in fatty and hydrophilic food stimulants was investigated via mathematical modeling. The active films incorporated with 20% ROE have significantly higher oxygen barrier and oxygen transfer is reduced by 20% compared to the control. A tortuous path is created with ROE, which impedes oxygen movement across the film. ROE addition improved water resistance performance by reducing the active film swelling ratio by 31%. This improvement is attributed to the hydrophobic nature of ROE. FTIR shows that the interaction between ROE and the active film is primarily hydrogen bonding and electrostatic interactions. Active film exhibits excellent antioxidant activity, with high TPC, DPPH scavenging activity, and FRAP. Mathematical modeling revealed a higher diffusivity (D) of ROE in fatty food stimulants at 24 °C, attributed to high polarity and solubility in fatty food stimulants. Overall, this active film has an excellent antioxidant effect and could potentially be used as food packaging for high-fat food products to prevent oxidation.
The emulsifying capacity of surfactants (polysorbate 20, polysorbate 80 and soy lecithin) and proteins (soy protein isolate and whey protein isolate) in flaxseed oil was measured based on 1 % (w/w) of emulsifier. Surfactants showed significantly higher emulsifying capacity compared to the proteins (soy protein isolate and whey protein isolate) in flaxseed oil. The emulsion stability of the flaxseed oil emulsions with whey protein isolate (10 % w/w) prepared using a mixer was ranked in the following order: 1,000 rpm (58 min) ≈ 1,000 rpm (29 min) ≈ 2,000 rpm (35 min) >2,000 rpm (17.5 min). The emulsion stability of the flaxseed oil emulsions with whey protein isolate (10 % w/w) prepared using a homogenizer (Ultra Turrax) was independent of the speed and mixing time. The mean particle size of the flaxseed oil emulsions prepared using the two mixing devices ranged from 23.99 ± 1.34 μm to 47.22 ± 1.99 μm where else the particle size distribution and microstructure of the flaxseed oil emulsions demonstrated using microscopic imaging were quite similar. The flaxseed oil emulsions had a similar apparent viscosity and exhibited shear thinning (pseudoplastic) behavior. The flaxseed oil emulsions had L* value above 70 and was in the red-yellow color region (positive a* and b* values).
Anthracnose, a postharvest disease caused by the fungus Colletotrichum capsici is the most devastating disease of bell pepper that causes great economic losses especially in tropical climates. Therefore, the objective of this study was to evaluate the antifungal properties of chitosan (low molecular weight from crab shell, Mw: 50 kDa and 75-85 % deacetylated) against anthracnose by inducing defense-related enzymes. The concentrations of 0, 0.5, 1.0, 1.5 and 2.0 % chitosan were used to control the fungus in vitro and postharvest. There was a reduction in C. capsici mycelial growth and the highest chitosan concentration (2.0 %) reduced the growth by 70 % after 7 days incubation. In germination test, the concentration of 1.5 and 2.0 % chitosan reduced spore germination in C. capsici between 80 % and 84 %, respectively. In postharvest trial the concentration of 1.5 % decreased the anthracnose severity in pepper fruit by approximately 76 % after 28 days of storage (10 ± 1 °C; 80 % RH). For enzymatic activities, the concentration of 1.5 and 2.0 % chitosan increased the polyphenol oxidase (PPO), peroxidase (POD) and total phenolics in inoculated bell pepper during storage. Based on these results, the chitosan presents antifungal properties against C. capsici, as well as potential to induce resistance on bell pepper.
The aim of this study is to report the yield of extraction, as well as the physicochemical and antioxidant properties of extracted chitosan from mud crabs (S.olivacea) as compared to commercial chitosan. The yield obtained for extracted chitosan was 44.57 ± 3.44 % with a moisture and ash content of 9.48 ± 0.59 % and 5.97 ± 0.90 %, respectively. Commercial chitosan demonstrated a higher degree of deacetylation (58.42 ± 2.67 %), water (250 ± 9.90 %) and fat (329 ± 7.07 %) binding capacity, solubility (73.85 %), viscosity (463.25 ± 13.10 %) and also the whiteness value (77.8 ± 0.47) compared to the extracted chitosan, which were only 53.42 ± 0.88 %, 180 ± 0.00 %, 260 ± 0.00 %, 53.38 %, 383.9 ± 28.43 % and 62.1 ± 7.52 %, respectively. The structure of extracted and commercial chitosan was also investigated using Fourier Transform Infrared Spectroscopy (FTIR). In conclusion, the extracted chitosan possessed potential properties similar to the commercial chitosan with high reducing power but low in the scavenging activity on the DPPH and hydroxyl radicals compared to the commercial chitosan.
A chronology of mathematical models for heat and mass transfer equation is proposed for the prediction of moisture and temperature behavior during drying using DIC (Détente Instantanée Contrôlée) or instant controlled pressure drop technique. DIC technique has the potential as most commonly used dehydration method for high impact food value including the nutrition maintenance and the best possible quality for food storage. The model is governed by the regression model, followed by 2D Fick's and Fourier's parabolic equation and 2D elliptic-parabolic equation in a rectangular slice. The models neglect the effect of shrinkage and radiation effects. The simulations of heat and mass transfer equations with parabolic and elliptic-parabolic types through some numerical methods based on finite difference method (FDM) have been illustrated. Intel®Core™2Duo processors with Linux operating system and C programming language have been considered as a computational platform for the simulation. Qualitative and quantitative differences between DIC technique and the conventional drying methods have been shown as a comparative.
Cinnamon deodorised aqueous extract (CinDAE) was prepared and evaluated for its total phenolic (315.3 ± 35.4 mg GAE/g) and flavonoid (99.3 ± 9.6 mg RE/g) contents. Stabilizing efficiency of CinDAE, for chicken meatballs, was measured against oxidative deterioration as function of storage time under chilled conditions. For this purpose, oxidative stability [2-thiobarbituric acid reactive substances (TBARS); peroxide value (PV)], colour and sensory acceptability were measured in the control meatballs (C), and those stabilized with 200 ppm of: CinDAE (T1), ascorbic acid (T2), BHA/BHT (50/50; w/w) (T3). In comparison to "C", induction period (IP) and redness (a* value) of the stabilized samples (T1, T2 and T3) were increased, while PV and TBARS were decreased throughout storage (8 ± 1 °C) significantly (p
This work aimed to evaluate the microstructural, physicochemical and sensorial properties of buffalo meat patties produced using different mixing equipment (bowl cutter, universal mixer, and meat mixer). Scanning electron microscopy revealed a more homogenize emulsion, cohesive structure and smaller pore size of patties produced using the bowl cutter, which significantly reduced the total fluid release, water release, fat release and cooking loss as compared to the universal mixer and meat mixer. Production of the buffalo meat patties using bowl cutter also improved the moisture retention and gel strength of the patties. The patties produced using bowl cutter had the significantly highest lightness and yellowness values, while the redness was the lowest. Lower hardness, gumminess and chewiness also were observed from the patties produced using bowl cutter. Quality of the microstructural and physicochemical properties of the patties produced using different equipment can be organized as bowl cutter > universal mixer > meat mixer. Nevertheless, the sensory evaluation demonstrated a higher preference on aroma, flavour and overall acceptability of patties produced using meat mixer due to coarser and meaty texture, while the colour, tenderness, juiciness and springiness did not differ against using bowl cutter and universal mixer.
A study of the literature indicates that chloroplasts synthesise a range of molecules, many of which have nutritional value for humans, but the nutritional credentials of chloroplasts recovered from plant cells are not established. Chloroplast-rich-fractions (CRFs) were prepared from green plant species and the macro- and micro-nutrient composition compared with the whole leaf materials (WLMs). The results indicated that, on a dry weight basis, CRF material from a range of green biomass was enriched in lipids and proteins, and in a range of micronutrients compared with the WLM. Vitamins E, pro-vitamin A, and lutein were all greater in CRF preparations. Of the minerals, iron was most notably concentrated in CRF. Spinach CRFs possessed the highest α-tocopherol [62 mg 100 g-1, dry weight (DW)], β-carotene (336 mg 100 g-1 DW) and lutein (341 mg 100 g-1 DW) contents, whilst grass CRFs had the highest concentration of alpha-linolenic acid (ALA) (69.5 mg g-1). The higher concentrations of α-tocopherol, β-carotene, lutein, ALA and trace minerals (Fe and Mn) in CRFs suggested their potential use as concentrated ingredients in food formulations deficient in these nutrients.
This paper reports on the extraction, partial characterization and the potential application of crude polysaccharides from defatted coconut residue as a prebiotic. The coconut residue was defatted and extracted to obtain the crude polysaccharides and its physicochemical properties were determined. The crude polysaccharides were assessed for monosaccharide composition, total carbohydrate content, reducing sugar concentration and protein content determination. The functional group and structural elucidation of crude polysaccharides was also done using Fourier transform infrared spectra analysis. The product was then subjected to artificial human gastric juice treatment to determine digestibility. Finally, an in vitro proliferation and acid production by two probiotic bacteria namely Lactobacillus casei Shirota and Lactobacillus bulgaricus were included in this study. It was found that the defatted coconut residue contained ash (0.54%), moisture (55.42%), protein (1.69%), crude fat (17.26%) and carbohydrate (25.73%). The percentage of crude polysaccharides extracted was 0.73 ± 0.04. The two fractions of monosaccharides obtained were glucose and fructose. Total carbohydrate content of DCR was 13.35% (w/v). The quantitative value of the reducing sugars obtained was 20.71%. Protein content in the crude polysaccharides was 0.009% and the peaks which indicated the presence of protein were observed at around 1640 cm(-1) (amide I) and 1530 cm(-1) (amide II). DCR crude polysaccharides were highly resistant (88%) to hydrolysis when subjected to artificial human gastric juice. The product was found to markedly stimulate two tested probiotics to proliferate and produce organic acids. All the above findings are supportive of the fact that polysaccharides extracted from DCR, an industrial waste, have a vast potential to be exploited as novel prebiotics.
A portable infrared spectroscopy system has been designed and developed for assessment of quality of mango fruit. This paper describes the design and development of a fruit quality grading device using reflectance mode optical sensor. The experiment was conducted to obtain the best results from the system and the device was correlated according to the measured output. In the experiment, several samples of mango fruits have been monitored for six days to study the relation how fruit quality increases with time as fruit ripens. Between the unripe mango fruit and the ripest one, a range of 3.5 V to 4.2 V was measured by the developed system. The rate of quality increase was calculated as an average of 6.7 mV per day. These results were used to correlate the final hardware and software development of the device. The results demonstrate that, portable near infrared spectroscopy is feasible for evaluating mango quality non-destructively.
The potential of laser light backscattering imaging was investigated for monitoring color parameters of seeded and seedless watermelons during storage. Two watermelon cultivars were harvested and stored for 3 weeks with seven measuring storage days (0, 4, 8, 12, 15, 18, and 21). The color parameters of watermelons were monitored using the conventional colorimetric methods (L*, a*, b*, C*, H*, and ∆E*) and laser light backscattering imaging system. A laser diode emitting at 658 nm and 30 mW power was used as a light source to obtain the backscattering image. The backscattering images were evaluated by the extraction of backscattering parameters based on the mean pixel values. The results showed that a good color prediction was achieved by the seedless watermelon with the R2 are all above 0.900. Thus, the application of the laser light backscattering imaging can be used for evaluating the color parameters of watermelons during the storage period.
Biobased food packaging materials are gaining more attention owing to their intrinsic biodegradable nature and renewability. Selection of suitable biobased polymers for food packaging applications could be a tedious task with potential mistakes in choosing the best materials. In this paper, an expert system was developed using Exsys Corvid software to select suitable biobased polymer materials for packaging fruits, dry food and dairy products. If - Then rule based system was utilized to accomplish the material selection process whereas a score system was formulated to facilitate the ranking of selected materials. The expert system selected materials that satisfied all constraints and selection results were presented in suitability sequence depending on their scores. The expert system selected polylactic acid (PLA) as the most suitable material.
The objective of this study was to develop biodegradable active film to improve the shelf-life of minimally processed fresh-produce. Guar gum (GG) based films with improved properties were fabricated by employing tween-80 (0.88%) as emulsifier, nanoclay (13.9%) as reinforcement, beeswax (1.21%) for hydrophobicity, glycerol (3.07%) as plasticizer, and grape pomace extract (5%) as active ingredient (%w/w of GG). Active films had a tensile strength of 122 MPa and water vapor transmission rate of 69 gm-2d-1. Films demonstrated significant antimicrobial activity against Escherichia coli, Staphylococcus aureus, Bacillus cereus, and Salmonella Typhimurium. The 2 kGy irradiated minimally processed pomegranate arils packed in film demonstrated a shelf-life of 12 days as compared to 4 days for unirradiated samples. The observed improvement in shelf-life was due to a radiation-induced release of antimicrobial volatiles from active films as confirmed by headspace analysis using GC-MS. Suitability of active films for food irradiation applications is thus demonstrated.
Lipid nanocarrier displays the advantages over conventional drug carriers as they are formulated with biodegradable and non-irritant lipids. However, the main drawbacks are the agglomeration of lipid particles, instability over storage, low drug loading, and the burst release of active ingredients. In this study, we investigated the effects of various polysorbate nonionic surfactants namely Tween 20, 40, 60, or 80 on the nanostructured lipid carrier (NLC). NLC incorporated with polysorbate nonionic surfactant was prepared by using high-pressure homogenization technique. The average size was reduced to 139.9 ± 15.8 nm in the presence of Tween 80 and remained stable in nano-size even incubated for 28 days. Encapsulation of l-ascorbic acid or Gold Tri.E 30 showed a high encapsulation efficiency of more than 75%, where the highest was Gold Tri.E in the presence of Tween 60 at 99.7%. In vitro release study showed that the release of both l-ascorbic acid and Gold Tri.E was significantly reduced in NLC with Tween as compared to bare active ingredients and NLC without Tween. In conclusion, the incorporation of Tween successfully produced a lipid nanocarrier that has the potential to be developed as a carrier of various active ingredients such as nutrients, extracts, and drugs.
Dielectric properties study is important in understanding the interaction between materials within electromagnetic field. By knowing and understanding the dielectric properties of materials, an efficient and effective microwave heating process and products can be designed. In this study, the dielectric properties of several encapsulation wall materials were measured using open-ended coaxial probe method. This method was selected due to its simplicity and high accuracy. All materials exhibited similar behavior. The result inferred that β-cyclodextrin (BC), starch (S), Arabic (GA) and maltodextrin (M) with various dextrose equivalent exhibited effective encapsulation wall materials in microwave encapsulation-drying technique owing to loss tangent values which were higher than 0.1 at general application frequency of 2.45 GHz. Thus, these were found to be suitable as wall material to encapsulate the selected core material in this microwave encapsulation-drying method. On contrary, sodium caseinate showed an ineffective wall material to be used in microwave encapsulation-drying. The differences in the values of dielectric constant, loss factor and loss tangent were found to be contributed by frequency, composition and bulk density.
This work studied the effectiveness of gaseous ozone disinfection on pummelo (Citrus Grandis L. Osbeck) fruit juice components. Unfiltered and filtered pummelo fruit juices were treated with gaseous ozone for up to 50 min with ozone concentration fixed at 600 mg/h. A microbiological and physicochemical properties analysis were conducted on the ozone-treated fruit juices samples. It was found that the survival rate of aerobic bacteria, yeast and mold in unfiltered pummelo fruit juice were higher compared to filtered juice, as the juice components acted as protective barriers to the microorganisms. The microorganisms' inactivation in pummelo fruit juices was also observed to have increased as the ozone treatment time increased. Significant effects on total colour difference, ascorbic acid content, and total phenolic content were also observed over increased ozone-treatment time. However, ozone was shown to be ineffective in activating PME activity in both types of juice. The experimental results of this study indicated that pummelo fruit juice components had significant effects on the effectiveness of gaseous ozone, however, the degree of the effects depends on the different fruit components (total soluble solids, total phenolic content). As a conclusion, filtered juice showed better quality characteristics in comparison to unfiltered juice post-ozone treatment.
Kenaf (Hibiscus cannabinus L.), an annual herbaceous plant in the Malvaceae family, has become a multifunctional crop in Malaysia due to its large number of industrial applications for its fibrous stem. Recently, its kenaf leaves that have high antioxidant properties are getting more attention to be developed into tea. Therefore, this research aims to determine the best brewing time and temperature based on the physical properties, antioxidant activities and sensory of kenaf leaves tea (KLT). The kenaf leaves powder which was infused in hot (80 °C or 100 °C; 5 min or 10 min) or cold water (room temperature; 60 min or 120 min) were analysed. Results demonstrated that the KLT brewed at 80 °C for 10 min and 100 °C for 10 min showed the highest antioxidant activities in most of the antioxidant analysis conducted. Moreover, the colour of cold-brewed KLT was much lighter than the hot-brewed KLT and the cold-brewed KLT (room temperature; 120 min) can likely be a new trend for the consumer since it contained high antioxidising capabilities. However, the pH, greenness, yellowness, sensory results in KLT were not affected significantly by both brewing time and temperature (p > 0.05). The antioxidant test was correlated positively with the phytochemical contents but insignificant relationship with most of the colour parameters. Overall, the optimum temperature and time for brewing KLT was 80 °C at 10 min because it saved energy and extracted the highest amount of antioxidants while retaining similar sensory taste with other brewing conditions.
The effects of different cooking methods (boiling, baking, frying and grilling) on proximate and mineral composition of snakehead fish were investigated. The mean content of moisture, protein, fat and ash of raw fish was found to be 77.2 ± 2.39, 13.9 ± 2.89, 5.9 ± 0.45 and 0.77 ± 0.12% respectively. The changes in the amount of protein and fat were found to be significantly higher in frying and grilling fish. The ash content increased significantly whereas that of the minerals (Na, K, Ca, Mg, Fe, Zn and Mn) was not affected in all cooking methods. Increased in Cu contents and decreased in P contents were observed in all cooking methods except grilling. In the present study, the grilling method of cooking is found to be the best for healthy eating.