Burapha Science Journal

Effect of Carrageenan and Glucomannan on Nipa Syrup Jellies and Their Potential for Development as Gelatin-Free Gummy Jellies

2025-04-10T11:23:08+07:00

Background and Objectives : Nipa syrup, a concentrated product derived from the sap of the nipa palm, contains a high total soluble solid content of 60-70 °Brix, making it often impractical for direct consumption. Therefore, development of new jelly products made of nipa syrup would enhance its practicality and convenience for consumption. The mixture of carrageenan (CG) and glucomannan (GM) as hydrocolloids has been shown to enhance the gel strength and improved water retention, thereby rendering them highly suitable for jelly and gummy jelly products. This study aims to evaluate the quality characteristics of nipa syrup and investigate chemical and physical properties, including sensory evaluation of nipa syrup jellies. Additionally, these plant-based hydrocolloids offer an alternative to gelatin-free gummy product. So, the potential of producing gelatin-free gummy jellies from nipa syrup was also studied to create a value-added product for today's consumers.

Methodology : Local nipa syrup was analyzed for pH, total acidity, total sugar, moisture content, total soluble solid, water activity (a_w), color values (L*, a* and b*), and viscosity. Literature reviews and preliminary experiments were investigated to obtain nipa syrup-based jellies (data not reported). The resulting basic ingredients were composed of water, nipa syrup, sugar, brown sugar, citric acid and sodium citrate at 74.1%, 15.0%, 9.0%, 1.0%, 0.4% and 0.5%, respectively. CG and/or GM were added at 1% of the total mixture. The effect of CG:GM ratios (ranging from 10:0 to 0:10) on nipa syrup jellies was examined through chemical properties (pH value, acidity and moisture content), physical properties (color and texture) and sensory attributes. The texture profile analysis (TPA) was carried out using a texture analyzer, attached with a 10-Kg load cell. The textural properties of the jelly gel in parameters of hardness, springiness, gumminess and chewiness were calculated with the help of software provided along with the instrument. Assessment of sensory evaluations (appearance, color, odor, texture, taste and overall liking) by 30 panelists was performed employing a 9-hedonic scale ranging from 1 (dislike extremely) to 9 (like extremely). The optimal nipa syrup concentration (15-25%) was determined by analyzing chemical properties, color, and sensory attributes. The feasible production of gelatin-free gummy jellies was assessed by drying jelly gel at 60°C for 0-8 hrs. The dried gel was then analyzed of chemical properties and textural characteristics.

Main Results : The results showed that the pH value of nipa syrup was 5.21 with a_w of 0.80, and it consisted of 31.69% moisture, 1.26% total acidity, 28.09% reducing sugar and 78.27% total sugar with total soluble solid of 67.8 °Brix. The color values of nipa syrup were recorded as L* 56.41, a* 21.15, and b* 34.37, with a viscosity of 135.3 cPs. The ratio of CG to GM at 6:4 increased in hardness, springiness, gumminess and chewiness of nipa syrup jelly gel by using a texture analyzer. The sensory evaluations showed that the ratios of 6:4 and 8:2 were not significantly different (p ≥ 0.05) in overall liking, ranging from moderate to very much liked score assessed by sensory panelists. The jelly with 20.0% nipa syrup-based exhibited a pH of 4.06, 0.65% total acidity, 71.75% moisture content and color values of L*, a* and b* were 21.96, 2.62 and 3.97, respectively. In addition, the highest score of overall liking (7.73), ranging from moderate to very much liked was also obtained. Hot-air drying at 60°C for 6 hrs effectively reduced the moisture content in the gel, resulting in higher hardness, chewiness, and cohesiveness, while the pH and total acidity were stable. The drying gel demonstrated characteristics of gummy jelly with a chewy texture that was easy to bite and not excessively firm. This drying method demonstrates potential as a viable approach to produce gelatin-free gummy jellies from nipa syrup.

Conclusions : This research demonstrated that nipa syrup, derived from nipa palm sap, could be produced a nipa syrup-based jelly product with the two mixture of hydrocolloids, CG and GM. The value added nipa syrup jelly with CG and GM provided a stable structure and good textural properties. The gelatin-free gummy jelly was also possibly produced. The results showed that the local nipa syrup revealed a pH of 5.21, 31.69% moisture content, 28.09% reducing sugars, and 78.27% total sugars with a viscosity of 135.3 cPs. The jelly with CG:GM at a ratio of 6:4 provided a gel with desirable hardness, springiness, gumminess and chewiness, achieving the highest overall liking scores by panelists, ranging from moderate to high preference but not significantly different with a ratio of 8:2. The 20% nipa syrup in jelly showed a pH of 4.06 and 71.75% moisture content with the highest overall liking scores. For the production of gummy jelly, hot air drying at 60°C for 6 hrs effectively reduced moisture content in gel and enhanced hardness, gumminess and chewiness, while the pH and acidity was maintained. These findings highlight the development of jelly and gelatin-free gummy jelly products to commercially add value to nipa syrup.

Synthesis of 4-Methoxycinnamyl Alcohol and Its Derivatives via Lithium Aluminium Hydride : Investigation of Reduction Product Formation by qNMR Analysis

2025-03-28T12:46:55+07:00

Background and Objectives : Natural products can be obtained through synthesis, either to increase quantity or improve quality. 4-methoxycinnamyl alcohol, found in Etlingera pavieana (Pierre ex Gagnep.) R.M.Sm. and Foeniculum vulgare Mill, is the target compound for synthesis in this research. It serves as a precursor for synthesizing 4-methoxycinnamyl p-coumarate (MCC), a compound with interesting bioactive properties in pharmaceuticals and cosmetics. These properties include anti-inflammatory, antioxidant, and tyrosinase inhibitory effects, making MCC a potential candidate for drug and cosmetic applications. However, a challenge encountered in synthesizing 4-methoxycinnamyl alcohol via the reduction of 4-methoxycinnamic acid with lithium aluminum hydride is the formation of side products due to the reduction of the double bond, leading to a lower yield of the main product and difficulty in purification. This issue arises because lithium aluminum hydride is a strong reducing agent that tends to react with both the carboxyl group and the conjugated double bond, leading to a mixture of reduced products. Therefore, this study aims to investigate reaction conditions to minimize side product formation and to synthesize derivatives of 4-methoxycinnamyl alcohol under optimal conditions. The study also explores the influence of different substituents on the reaction outcome. The product yields were analyzed using quantitative Nuclear Magnetic Resonance (qNMR) with acetanilide as an internal standard.

Methodology: The study began with optimizing the conditions for synthesizing 4-methoxycinnamyl alcohol by controlling key reaction factors, including lithium aluminum hydride quantity, reaction time, and temperature. The initial amount of lithium aluminum hydride was set at 0.5 equiv., increasing in increments of 0.5 equiv. The reaction was conducted under an argon atmosphere at room temperature to 0°C for 4 to 24 hours. Once the optimal conditions were identified, they were applied to synthesizing derivatives of 4-methoxycinnamyl alcohol by modifying the para-substituent groups, including hydrogen (H) from cinnamic acid, hydroxy group (OH) from coumaric acid, and O-tetrahydropyranyl group (OTHP) from 4-(tetrahydro-2H-pyran-2-yloxy) cinnamic acid. These derivatives were selected to examine the effects of electronic and steric factors on the reaction pathway. Finally, the yields of both the main and side products were analyzed using qNMR, with acetanilide as an internal standard.

Main Results: The experimental results revealed that increasing the amount of lithium aluminum hydride at the same reaction time and temperature led to a higher formation of side products. This suggests that excess lithium aluminum hydride promotes non-selective reduction, affecting both the carboxyl and double bond functionalities. Therefore, reaction time was increased while keeping lithium aluminum hydride quantity constant at 0.2 equiv. at room temperature to observe the reaction trend. It was found that significant side product formation persisted, indicating that temperature might be a more influential factor in controlling selectivity. Subsequently, lowering the temperature to 0°C while maintaining the lithium aluminum hydride amount at 0.2 equiv. for 4 hours resulted in a higher yield of the main product. This confirms that temperature plays a crucial role in directing the reduction pathway. Increasing the lithium aluminum hydride quantity to 3.0 equiv. further improved the main product yield, likely due to enhanced reduction efficiency at the carboxyl site. However, extending the reaction time to 8 hours did not significantly change the yield, suggesting that the reaction reaches equilibrium within 4 hours. Therefore, the optimal conditions for synthesis were determined to be 3.0 equiv. of lithium aluminum hydride at 0°C for 4 hours, balancing high yield and selectivity. However, when these conditions were applied to synthesizing derivatives of 4-methoxycinnamyl alcohol, the yields of the main products remained low to moderate, with minor side product formation. This was attributed to the resonance and steric effects of electron-donating groups and structural factors of the compounds. The presence of hydroxyl groups, for example, influenced the electronic environment, potentially altering the reduction pathway. Similarly, the bulky tetrahydropyranyl group affected steric accessibility, leading to different product distributions.

Conclusions: The synthesis of compound 4-methoxycinnamyl alcohol via reduction under an argon atmosphere using lithium aluminum hydride showed that lowering the temperature reduced double bond reduction but did not significantly enhance selectivity toward the carboxyl group. Increasing the quantity of lithium aluminum hydride and reaction time improved carboxyl reduction and overall yield. However, excessive reaction time could lead to consecutive reactions or degradation of the starting material, highlighting the importance of balancing reaction parameters. The most suitable conditions for synthesis were 3.0 equiv. of lithium aluminum hydride at 0°C for 4 hours, yielding a moderate amount of the main product with minimal side products. Nevertheless, these conditions were not optimal for synthesizing derivatives of 4-methoxycinnamyl alcohol due to the impact of structure and substituent groups on yield. Further investigation in this study, such as the use of alternative reducing agents or protective group strategies, may enhance the yield of the main product and minimize side product formation. This research provides valuable insights into the influence of reaction conditions on reduction selectivity, which can be applied to similar synthetic processes in natural product and pharmaceutical chemistry.

Determination of Mercury (II) Ion Using Rhodamine 6 G Hydrazide on Natural Polymers Derivative Solid Support

2025-04-04T11:48:15+07:00

Background and Objectives : Mercury (II) ions (Hg²⁺) are highly toxic metal ions, and even minor contamination in water sources can adversely affect living organisms. When the body is exposed, permanent damage is done to the genetic material, nervous system, and brain. The World Health Organization (WHO) has established that the concentration of inorganic mercury in drinking water should not exceed 29.9 nanomolar. Therefore, the development of a detection kit for mercury (II) ions is crucial. In this study, a detection kit for Hg²⁺ ions in the form of an environmentally friendly film was developed. The film was prepared by incorporating Rhodamine 6G hydrazide (L6G) into a cellulose triacetate (CTA) matrix, a cellulose derivative, with tris(2-ethylhexyl) phosphate (TEHP) as a plasticizer. Previous reports have indicated that L6G molecules exhibit high selectivity toward Hg²⁺ ion in a 10% tetrahydrofuran (THF) solution. However, this solvent limitation prevents L6G from detecting Hg²⁺ ion in aqueous samples. It was hypothesized that the L6G-based film developed in this study could be used for the detection of Hg²⁺ ions in water samples.

Methodology : The L6G film was prepared using the casting method by mixing Rhodamine 6G hydrazide (L6G) with cellulose triacetate (CTA) with tris(2-ethylhexyl)phosphate (TEHP) serving as a plasticizer. The selectivity of the film for metal ion detection was investigated by immersing the prepared film in solutions containing various metal ions. The film intensity was measured using Image J program. Additionally, the optimal conditions for film preparation were studied, including the appropriate amounts of CTA, TEHP, and ligand L6G. The optimal conditions for using the film as a detection kit were also examined, including the appropriate detection time, the effect of pH and the concentration range of mercury (II) ion interacting with the L6G film. Moreover, the detection limit and limit of quantification of film L6G towards mercury (II) ion were also studied.

Main Results : The prepared L6G film was observed to have a smooth, pale pink appearance and to be water-insoluble under the studied optimal conditions. The prepared film was tested for its ability to selectively detect metal ions in water, and it was determined that L6G film exhibited high specificity for Hg²⁺ ions. This was evidenced by a color change of the film from pale pink to purple, which occurred exclusively in the presence of Hg²⁺ ions. This color change resulted from the coordination covalent bonding between Hg²⁺ ions and the L6G ligand within the film. As a consequence of electron donation from oxygen and nitrogen atoms in the L6G ligand, a color change from pale pink to purple was observed in the film due to spirolactam ring opening. The optimal conditions for preparing the L6G film were investigated. It was found that the most suitable amount of CTA was 0.2 grams, as this quantity produced a transparent film with an appropriate thickness. If the amount of CTA is too low, a thin film will be obtained, whereas an excessive amount of CTA results in a thick film. The TEHP content was identified as being optimal at 0.05 grams, as any excess led to the formation of a rigid, matte film, which obstructed water penetration. The L6G ligand amount was best at 6.0 milligrams, yielding the highest color intensity, whereas excessive L6G led to an opaque and non-uniform film Based on the study of optimal conditions for detecting Hg²⁺ ions in aqueous solutions, the L6G film was found to require an ideal immersion time of 180 minutes at a pH of 5.0. The detection was conducted at 0 minutes, immediately after the film was removed from the solution, dried, and its color intensity measured. The concentration range of Hg²⁺ ions that exhibited the strongest linear correlation with film color intensity was found to be 0 – 10 ppm, with an R² value of 0.9984. The detection limit and the minimum measurable concentration of mercury (II) ions using the L6G film were measured at 0.51 ppm and 1.66 ppm, respectively.

Conclusions : In this research, an optical chemical sensor in the form of a film was developed for the detection of Hg²⁺ ions dissolved in water. The sensor molecule, rhodamine 6G hydrazide (L6G), was incorporated into cellulose triacetate (CTA) using the casting method, with THEP serving as a plasticizer. The prepared detection film was found to be a thin, transparent, pale pink sheet that was water-insoluble and stable in aqueous environments. Based on the selectivity study of the prepared film for sensing metal ions, the film was observed to exhibit high specificity toward Hg²⁺ ions in which the film’s color changing from pale pink to purple, whereas other metal ions did not interfere with the sensing process. Therefore, the capability of the developed colorimetric detection kit to detect Hg²⁺ ions in aqueous solutions has been demonstrated. One of the benefits of preparing the film using this method is its simplicity, as it does not require expensive tools or equipment.

Biological Development of the Fighting Beetle (Xylotrupes gideon) in a Confined Rearing System

2025-02-14T00:21:34+07:00

Background and Objectives : The fighting beetle (Xylotrupes gideon) plays an important role in the ecosystem, contributing significantly to nutrient cycling and soil enrichment through the consumption of decaying plant matter during their larval stages. Furthermore, the adult beetle is a viable food source for humans, presenting an opportunity for sustainable food production. Populations in their natural habitats are currently declining due to several factors, including the destruction of natural habitats, which limits the beetles' ability to reproduce, pollution from agricultural practices involving chemical use and overharvesting for consumption. Although some aspects of this insect's biology were explored, the complete biology of this species, particularly that of the pre-adult stages, which reside underground, remains little known due to the difficulty of observation. This study aimed to investigate the complete life cycle and developmental biology of the fighting beetle from the egg stage to the reproductive adult stage, under controlled, confined rearing conditions, utilizing an artificial diet to mimic their natural food sources.

Methodology : Five breeding pairs of healthy males and females were used for offspring production. Subsequently, mated females were allowed to oviposit in a 25×22 cm culture pot filled with a fermented sawdust artificial diet. After allowing for 5 days for oviposition, eggs were verified via careful examination. Ten eggs were carefully selected from a single female and were meticulously monitored under a stereomicroscope to analyze the developmental processes occurring before the larval stage. The majority of the eggs obtained from all five female beetles were incubated until they successfully hatched into first instar larva (L1). Subsequently, 100 larvae (L1) were individually reared in 32-ounce plastic cups until they developed into the reproductive adult stage. Throughout the developmental period, data on the number of eggs per female, larval morphology at each instar, body weight, developmental duration, survival rate, sex ratio, and adult lifespan were recorded.

Main Results : The study demonstrated that the fighting beetle can be successfully reared in a confined rearing system using a formulated artificial diet that mimics their natural food source, allowing them to develop into reproductive adults. The average number of eggs laid per female was 34.20 ± 12.19. The eggs were white, oval-shaped, and approximately 0.3 cm in length. Fertilized eggs exhibited progressive developmental changes as observed through stereomicroscopy. Observation of eggs collected 5 days after oviposition revealed a translucent appearance. By 10 days post-female oviposition, the eggs had increased in size, and an opaque spot was observed, indicating embryonic development. By 15 days post-female oviposition, larval development was observed with clear segmentation of the body. By 25 days post-female oviposition, significant development was apparent with pigmentation of the body and clearly distinguishable head and mandible structures. These eggs hatched into L1 larvae after approximately 25-30 days. Newly hatched L1 showed a white head and body with reddish-brown hair on the body. The head color transitioned to brown over time. Larval development progressed through molting, with larvae molting from L1 to L2 and L2 to L3, with each stage approximately 30 days. The L3 larval stage took approximately 180 days. At the late L3 stage, the larva made a pupation chamber and their transparent skin changed to yellow and wrinkled before developing into a pupa stage. The durations from the pupa-teneral adult, teneral adult-reproductive adult and reproductive adult-natural death stages were 21.38±2.26, 32.82±3.24 and 53.81±15.59 days, respectively. The survival rates (%) from L1-L2, L2-L3, L3-pupa, pupa-teneral adult, and teneral adult-reproductive adult stages were 100, 92, 82, 82, and 71%, respectively. Forming a pupation chamber by L3 larva is a prominent behavior, providing an open space for pupal and adult development. The pupation chamber of this species was oval-shaped with rounded ends and possessed thick and rigid walls. This study yielded 41 reproductive adult males and 30 reproductive adult females, resulting in a male-to-female sex ratio of 1.00:0.73. A chi-square test indicated that this ratio was not statistically significant. Males exhibited variations in horn length. The coloration of adult fighting beetles from this study was classified into two primary groups: reddish-brown and black. Reddish-brown was the predominant color observed in the reared beetles. Within the reddish-brown group, there were varying shades that didn’t form distinct subgroups.

Conclusions : This study successfully reared the fighting beetle, elucidating their biology from the egg to the reproductive adult stages, under confined condition and using an artificial diet. The diet was formulated with rubber sawdust, dried cow manure, soil, wheat flour and water, mixed in specific proportions. The 71% survival rate of the fighting beetle from the larval stage to the reproductive adult stage under solitary rearing conditions (limited space) indicates that the formulated diet is adequate for supporting their development to the reproductive adult stage. This study provides critical insights into the feasibility and optimization of large-scale rearing for various applications, including sustainable conservation, commercial sale and alternative protein production from edible insect.

Effect of Dried Sweet Corn Cake Powder Substitution on Quality of Cookies

2025-01-31T11:44:40+07:00

Background and Objectives : The sweet corn milk product from the National Corn and Sorghum Research Center is widely popular among people of all ages due to its unique aroma and pleasing taste. This has resulted in a large quantity of sweet corn milk being produced and released into the market, leading to a significant amount of corn residue, which is a by–product of the production process. The manufacturer sells this corn residue to be used as animal feed, amounting to approximately 900–1,000 kilograms per day. Therefore, to increase the value of agricultural by–products and reduce the use of wheat flour, while also enhancing the nutritional value of the developed products. The objective of this research is to investigate the optimal utilization of wheat flour supplemented with dried sweet corn cake (DSCP) in cookies. The ideal amount of sweet corn residue accepted by consumers was determined in this study.

Methodology : Sweet corn cake powder was prepared by drying fresh sweet corn cake in a hot air oven at 70 degrees Celsius for 24 hours, then grinding and sieving it into a fine yellow powder. The DSCP is analyzed for its physicochemical properties, including color value, beta-carotene content, total phenolic content, and antioxidant activity using the DPPH and ABTS free radical scavenging assay methods. Before using the DSCP to replace wheat flour in cookies, a basic recipe for cookie production was selected. This was done by evaluating five different cookie recipes using sensory evaluation with 50 general panelists as testers. The basic recipe that received the highest overall liking score from the panels was further developed into a cookie recipe by replacing wheat flour with DSCP. Utilization of DSCP for replacing wheat flour by 25, 50, 75 and 100% (w/w) of total flour in cookie were studied. The effect of DSCP supplementation on physical and chemical characteristics, including width, thickness, spread ratio, hardness, color value, water activity, proximate analysis (moisture, protein, fat, ash, carbohydrates and dietary fiber), beta-carotene content, total phenolic content and antioxidant activity were measured using the DPPH and ABTS free radical scavenging assays. The sensory quality attributes of the cookies were evaluated, including overall acceptance, appearance, color, taste, texture, and flavor.

Main Results : The dried and finely ground sweet corn residue powder was found to have lightness (L*), redness (a*), and yellowness (b*) values of 77.39, 7.68, and 37.83, respectively. The chroma (C*) value was 38.60, the hue angle (h°) was 78.51, which corresponds to a color range from orange-red to yellow and color different (E) was 16.30. Additionally, the DSCP contained beta-carotene at 350.52 µg/100 g, a total phenolic content of 55.36 mg GAE/100 g DW and antioxidant activities measured by the DPPH and ABTS methods at 94.48 and 44.72 mg TE/100 g DW, respectively. For the results of the basic cookie selection, it was found that the basic cookie recipe formula 4 had higher liking scores of all sensory characteristics than other formulas. The main ingredients of the optimum basic formulation of cookie products included all–purpose wheat flour, sugar, salted butter, eggs, baking powder and baking soda at 27.18%, 27.18%, 36.35%, 8.95%, 0.23 and 0.11%, respectively. Therefore, the basic formula 4 was selected to study the optimum level of wheat flour replacement with sweet corn cake powder. It was found that adding DSCP to the cookies had no significant effect on width, thickness, or spread ratio (p>0.05), except for hardness and water activity which increased with the substitution level (p≤0.05). Additionally, the cookies showed a decrease in lightness, while redness and yellowness values increased significantly (p≤0.05). The chroma value and E increased, while the hue angle decreased as the substitution level of DSCP increased, ranging from 63.92 to 75.36, indicating a color range from orange-red to yellow. The proximate results of the cookies showed an increase in moisture content (2.00–3.39%), protein (5.95–8.60%), fat (28.67–32.22%), ash (1.08–2.01%) and total dietary fiber (1.14–8.64%) as well as decrease in carbohydrate (63.32–53.79) as substitution level of DSCP increase (p£0.05). Furthermore, the cookies also showed a significant increase in beta–carotene content, total phenolic content and antioxidant activity when analyzed using the DPPH and ABTS assays (p£0.05). The results from sensory evaluation showed that the sample containing 25% DSCP had no difference of overall linking score comparable to the control (p>0.05).

Conclusions : The optimal substitution ratio of DSCP for wheat flour was 25%, as the overall liking score was not significantly different from the control sample (p>0.05). This formulation exhibited a lightness of 57.28, redness of 6.51, yellowness of 18.04, chroma of 21.88 and hue angle of 71.93, indicating a color range from orange-red to yellow. The chemical compositions of cookies with 25% DSCP consist of moisture, protein, total fat, ash, total carbohydrate and total dietary fiber at 2.47, 6.77, 29.58, 1.27, 59.92 and 2.28%, respectively. Beta-carotene and total phenolic content were 55.59 µg/100g sample and 98.62 mg GAE/100g DW, respectively. Furthermore, the DPPH and ABTS radical scavenging activities were 12.59 and 35.16 mg TE/100g DW, respectively. It could be concluded that the use of DSCP had potential to enhance the nutritional and antioxidant potential of cookies.