Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering)

Author Index

Editor JTEP-L — 2026-01-08

Subject Index

Editor JTEP-L — 2026-01-12

Preface December 2025

Editor JTEP-L — 2026-01-06

The Effect of Dosage and Frequency of Potassium Fertilization on the Growth and Yield of White Eggplant (Solanum melongena L. var. Kania)

Kholid Ihsan Abdulloh — 2025-12-04

Eggplant plants have a high flower drop rate, resulting in a low fruit set. Potassium fertilizer plays an important role in plant physiology and can help reduce flower drop. This study aims to determine the effect of dosage and frequency of potassium fertilization on the growth and yield of white eggplants. The research was conducted in Mojosari District, Mojokerto Regency, East Java, from December 2023 to March 2024. This research was a factorial study with two factors arranged in a Completely Randomized Design. The first factor is potassium fertilizer dosage, which included 3 levels (3, 6, and 9 g/plant), and the second factor is fertilization frequency, which included 3 levels (2, 3, and 4 times). Results showed that the combination of potassium fertilizer dosage of 9 g/plant with potassium fertilization frequency of 4 times was the best treatment combination for fruit weight per plant, with an increase of 114% compared to the combination of potassium fertilizer dosage of 3 g/plant and potassium fertilization frequency of 2 times.

Product Formulation of Ready to Use Fish Food (RUFF) from Snakehead Fish Flour (Channa striata)

Puspo Edi Giriwono — 2025-12-04

RUFF (ready-to-use fish food) is a nutrient and calorie-dense food with high protein and energy consumed by children under five years of age who suffer from severe acute malnutrition. RUFF in this study was designed to be the alternative product for RUTF (ready-to-use therapeutic food) using snakehead fish flour as skim milk substitute. This study aims to determine the suitability of snakehead fish flour as an animal protein alternative, obtain the RUFF formula that meets FAO and WHO standards, and determine the consumer acceptance. The research investigated different amount of snakehead fish flour in the RUFF formulation. There were 3 formulas with different snakehead fish flour, i.e. 20% (F1), 22% (F2), and 24% (F3). The results of the analysis showed that the highest protein content was found in formula F3 (14.35 ±0.72)% with moisture content of 2.32 ± 0.06%, ash content of 2.56 ± 0.04%, fat content of 29.39 ± 0.24%, and carbohydrate content of 51.37 ± 0.94%. All three RUFF formulations meet the nutritional standards set by the FAO and WHO. The hedonic rating test results and ranking showed that the most preferred formula by the panelist was formula F1 containing 20% snakehead fish flour with an average rate of 7.46 (like). Formula F1 is the formula of RUFF with the highest rate of consumer acceptance.

The Role of Fan Speed and Misting for Computational Fluid Dynamics (CFD) Analysis of Temperature and Humidity Regulation in Greenhouses

Renny Eka Putri — 2025-12-04

Maintaining an optimal climate is essential for plant growth, and greenhouses though controlled often face challenges such as excessive heat. To address this, fan and misting systems are commonly used. This study investigates the role of fan speed and misting in regulating temperature and relative humidity (RH) in a smart greenhouse using Computational Fluid Dynamics (CFD) simulations. In this research, CFD simulations were performed using actual temperature and RH measurements as input data. The scenarios included varying fan speeds (3.4 m/s, 4.5 m/s) and a control condition without a fan, combined with 15-minute misting sessions. The results show that a fan speed of 4.5 m/s with misting is more effective at lowering temperature compared to 3.4 m/s under the same misting conditions. The simulation errors were below 10% across all treatments, indicating the model’s reliability. These findings offer valuable insights for optimizing climate control in greenhouses, supporting more efficient and sustainable crop production.

Effect of IBA (Indole Butyric Acid) Concentration on the Growth of Avocado Plant Cuttings (Persea americana Mill)

Maulida Safira — 2025-12-05

The demand for avocados in Indonesia continues to rise, while the availability of high-quality seedlings remains limited. Propagation through stem cuttings with the application of IBA (Indole Butyric Acid) is expected to improve propagation success. This study aims to determine the effect of IBA concentration on the growth of avocado stem cuttings. The research was conducted in Bojonegoro, East Java, using a Completely Randomized Design (CRD) with one factor, namely five concentrations of IBA: 0, 75, 100, 125, and 150 ppm. Observed parameters included shoot length, number of shoots, number of leaves, and number of primary roots. The results showed that IBA concentration had a significant effect on all observed parameters, while cutting length had no significant effect. A concentration of 100 ppm produced optimal growth of 1.92 cm, 2.50 shoots, and 4.33 leaves. The treatment without IBA resulted in the lowest values. The application of IBA at concentrations of 75–100 ppm effectively enhanced the growth of avocado stem cuttings, particularly in shoot and leaf development.

Effect of Indole Butyric Acid (IBA) Application and Spliced Grafting on the Growth of Garuda Clone Cassava

Menis Triana — 2025-12-05

Increasing cassava production is required to maintain supply sustainability and meet seed demand. The use of splice grafting and the application of auxin IBA are expected to accelerate rooting and enhance the productivity of cassava. The objective of this research is to study the effect of IBA application on the growth of cuttings and grafted seedlings of cassava. The research was conducted from October 2024 to February 2025 at the Integrated Field Laboratory of the Faculty of Agriculture, University of Lampung, Natar District, South Lampung. The experiment was designed according to randomized block design (RBD) with factorial treatments arrangement (3×2). The first factor was IBA concentration consisted of three levels, namely without IBA (A0), 1000 ppm (A1), and 2000 ppm IBA (A2). The second factor consisted of 2 types of plant materials, namely cuttings seedlings (B1) and slanted graft seedlings (B2). The results show that the application of IBA significantly increases the growth and production of cassava compared to without IBA application. IBA at 2000 ppm is the best concentration for the observed variables. The use of planting materials, whether cuttings or slanted grafts, both enhance the yield of cassava.

Probabilistic Estimation of Bromate Exposure from the Consumption of Bottled Drinking Water Distributed in the Bogor Region

Yani Handayani — 2025-12-05

Bottled drinking water is a source of human exposure to bromate, a disinfection by-product (DBP) with adverse health effects and carcinogenic potential. Little is known about bromate exposure levels and risk characterization, particularly in Bogor, Indonesia. The study aimed to obtain data on bromate concentrations in bottled drinking water, estimate bromate exposure levels based on individual consumption, and assess the risk characterization. Bromate exposure were calculated based on bromate concentrations and individual consumption, across five age groups. Bromate exposure and risk characterization were estimated probabilistically using Monte Carlo simulation. In this study, 37 bottled drinking water samples were collected from large and small manufacturers and retailers in Bogor and analyzed for bromate content. Bromate was detected in 30 samples, with 5 samples exceeding the Indonesian national standard of 10 µg/L. The average concentration was 6.88±8.88 μg/L. Exposure estimates indicate that, for all age groups, the average and 95th percentile values are 0.1086±0.0484 µg/kg BW/day and 0.4044 µg/kg BW/day in Bogor and 0.1492±0.2820 µg/kg BW/day and 0.5495 µg/kg BW/day in Indonesia, respectively. Values below the tolerable daily intake (TDI) limit for non-cancer risk, so the risk characterization for all age groups can be considered as safe.

Economic Feasibility of Embankment Construction with a Polder System for Optimizing Sustainable Palm Oil Cultivation

Hermantoro Hermantoro — 2025-12-05

Lowland areas in oil palm plantations is often flooded due to river overflows and high rainfall, which results in reducing oil palm productivity. This research aims to analyze the feasibility of investing in building embankments with a polder system to optimize lowland areas for sustainable oil palm cultivation. The research method uses a quantitative descriptive approach with financial analysis based on NPV, IRR, PP, PI, BCR and BEP parameters. The research results show that the polder system increases land productivity from 60–61% utilization to 100%, with an optimal projection of 136 trees/ha. Even though investment costs increased from IDR 11.8 billion to IDR 14.4 billion, the financial feasibility analysis resulted in a positive NPV of IDR 964,200,861, IRR 22.20% (> 20% discount), PP 10 years, PI 2.17 > 1, BCR 1.21 > 1 and BEP achieved in 10 years. In conclusion, building embankments with a polder system is financially and technically feasible, increasing productivity while reducing the risk of flooding. Recommendations include regular monitoring of the polder system and integration with sustainable cultivation practices

Utilization of Rice Flour and Soy Flour with the Addition of Xanthan Gum for Making Gluten-Free White Bread

Ratna Yulistiani — 2025-12-05

Gluten-free white bread formulated with rice and soy flour offers a safe alternative for individuals with celiac disease. Since gluten is absent, xanthan gum is added to improve gas retention and dough structure. This study aimed to identify the optimal formulation of gluten-free white bread by evaluating the physical, chemical, and sensory characteristics of various combinations of rice flour, soy flour, and xanthan gum, as well as analyzing the bread microstructure using Scanning Electron Microscopy (SEM). A Completely Randomized Design (CRD) with two factors- rice flour to soy flour ratios (90:10, 80:20, 70:30) and xanthan gum levels (1%, 2%, 3%)- was performed with three replications. Results showed that the best formula is rice flour to soy flour ratios of 80:20 combined with 3% xanthan gum. The bread had 39.26% water content, 1.26% ash, 10.96% fat, 8.22% protein, and 40.30% carbohydrates. Physically, it had a textural strength of 19.85 N, volume expansion of 82.64%, and porosity of 24.00%. Sensory scores (1-5 scale) were 4.24 (color), 3.92 (aroma), 3.96 (taste), and 4.68 (texture). SEM revealed that the gluten-free bread had larger and less uniform pores. These findings highlight formulation potential to enhance gluten-free bread quality and sensory acceptance.

Optimization of Sugar Reduction using Steviol Glycoside for Ready-to-Drink Sweetened Tea

Mintarsih — 2025-12-05

Excessive sugar consumption is a major contributor to increased calorie intake and the rising prevalence of obesity, particularly through sweetened ready-to-drink (RTD) teas. This study aimed to optimize formula of reduced sugar RTD tea using steviol glycoside as sweetener, in combination with maltodextrin and xanthan gum, through a mixture design approach. Steviol glycoside next called as stevia is a zero-calorie natural sweetener with a sweetness intensity approximately 300 times of sucrose. Maltodextrin was employed as filler, while xanthan gum was added to improve mouthfeel. The optimized formulation achieved a 2% reduction in sugar content using 0.009% stevia, 0.029% xanthan gum, and 1.962% maltodextrin. A reference product was formulated based on the most popular RTD jasmine black tea in the Indonesian market, which contains 7.7% (b/v) sugar per 100 mL. Result of spectrum descriptive analysis (SDA) sensory evaluation, conducted before and after ultra-high temperature (UHT) processing, showed no significant differences in sweetness, mouthfeel, astringency and jasmine aroma attributes. Compare to reference, in 100 mL product, sugar content was reduced from 7.68 to 5.78%, while total calorie slightly decreased from 30.71 to 30.13 kcal. In addition, the cost is slightly more expensive by IDR 126 per 350 mL package.

Design of an Automatic Temperature and Humidity Control System Prototype for Rice Seedling Nursery

Siswoyo Soekarno — 2025-12-05

Temperature and humidity control in rice nurseries is carried out to maintain the quality of rice seeds and avoid planting failure. Control is carried out using a prototype automatic device equipped with a water pump for watering and a mist maker plus a fan for humidifying. Based on observations, the prototype tool operates according to the given program. The water pump will turn on when the time shows 07:00 a.m. and 02:00 p.m. Meanwhile, the mist maker plus fan will turn on according to the regulated temperature and humidity conditions and can be applied to several regions in Indonesia. However, at the research site it will turn on when the temperature is > 27 °C and the humidity is < 70% and will turn off when the temperature reaches 27 °C and the humidity is 86%. The optimal air temperature for rice growth ranges from 19–27 °C with humidity in the RH range of 70–86%. Observations were carried out in two treatments, namely conditions with control and conditions without control. The results of seedling with control are better than without control. This can be seen from the growth of rice seedlings with control having a higher value than rice seedlings without control.

Effect of Azotobacter sp. and Cow Manure on Nitrogen Availability in Saline Soil, Root Length, and Vitamin C Content of Tomato

Aulifia Nisak Aisyah — 2025-12-05

Nitrogen is a macronutrient for plants, but its availability in saline soil is a limiting factor, making it difficult to cultivate plants. This study aims to examine the effect of the combination of Azotobacter sp. and cow manure in increasing the available N of saline soil, and to obtain the best combination in increasing the growth of tomato plants in saline soil. This research was conducted in the greenhouse and laboratory of UPN "Veteran" Jawa Timur. Saline soil samples came from the Wonorejo Mangrove land, Surabaya. Azotobacter sp. isolates came from the roots of Wonorejo mangrove trees. The study used a Completely Randomized Design with 2 factors with 3 replications. First factor was addition of Azotobacter sp., consisted of A0 (no addition of Azotobacter), and A1 (addition Azotobacter at 10⁷ CFU/mL. Second factor was cow manure (K) involved 4 levels (in ton/ha): A0 (0); K1 (20); K2 (30); K3 (40). The results of this research showed that application of Azotobacter sp. and cow manure affected the parameters of available N, EC, pH and vitamin C content, but did not affect the parameters of plant root length. Combination of Azotobacter 10⁷ CFU/mL + 40 tons/ha of cow manure produced the best available N of 246.48 ppm. The highest vitamin C content was 36.75 mg/g in the treatment of 10⁷ CFU/mL Azotobacter + 30 ton/ha of cow manure. Cow manure decreased soil EC and increased soil pH.

Effect of Drying and Size Reduction Techniques on the Characteristic of Instant Seasoning for Shredded Fish

Sela Julita — 2025-12-08

Instant seasoning for spiced shredded fish is practical and serves to expedite the process of producing shredded fish products. Instant seasoning has a potential to be developed and needs to be studied because it has not been found in the nearest supermarket. The objective of this study is to analyze and evaluate the quality of instant seasonings produced using various drying and size reduction techniques. The research was performed according to Completely Randomized Block Design, comprising two factors (i.e. drying techniques and size reduction techniques) and three replicates. Data was analyzed using the LSD (Least Significant Difference) and de Garmo tests to determine the most effective treatment. Seasoning quality was based on sensory attributes, chemical parameters, and microbiological parameters. The findings indicated that the application of drying and size reduction techniques had a discernible impact on the quality of instant seasoning for spiced shredded fish. The P3A1 (drying using food dehydrator and size reduction using chopper) treatment was determined to be optimal with 5.27% moisture content of, 8.57% fiber content, 42.88% free radical inhibition activity, 2.42 log CFU/ml total microbes, and 4.16 of score for overall acceptance.

Improvement of the Conditioning Process to Enhance the Quality of Vanilla (Vanilla planifolia)

Andi Ulfa Hardianty Syahrullah — 2025-12-08

The quality of national vanilla still does not fully meet national and international standards, one reason is the suboptimal conditioning process, namely, the final storage stage to stabilize quality. This study aims to examine the effect of packaging type, combined with temperature and conditioning duration, on vanilla's physical, chemical, sensory, and microbiological quality, and determine the best treatment combination in producing vanilla quality that meets SNI. Factorial Completely Randomized Design (CRD) was used in this experiment with three factors namely different material packaging (wax paper and HDPE plastic), various temperatures storage (25 °C, 30 °C, 35 °C), and conditioning durations (1, 1.5, and 2 months). Results showed that temperature, type of packaging, and conditioning duration significantly affect most of the physical, chemical, and microbiological quality parameters of vanilla, except for ash content and organoleptic aroma, which are not significantly different. The best treatment combination was obtained using HDPE packaging with a temperature of 35 °C for 1.5 months of conditioning, producing quality according to SNI 01-0010-2002 with high vanillin content and stable color. However, the total microbial count (TPC) in this treatment still exceeded the limits set by FAO.

Intention to Revisit Agrotourism: Effect of Service Quality and Visitor Experience

Imatul Hidayah — 2025-12-08

Agrowisata Kebun Belimbing in Bojonegoro faced a decline in visitor numbers from 2021 to 2023. To increase visitor interest to return, the Agrotourism needs to enhance the quality of experiences that tourists receive and enjoy. This study aims to examine how service quality and visitor experience affect revisit intention, with satisfaction function as a mediating variable. The research employed explanatory quantitative method with a Structural Equation Modeling - Partial Least Square (SEM-PLS) approach. As many as 100 respondents who have visited the agrotourism was selected purposively. Data was collected through an online questionnaire and was analyzed using WarpPLS software. The results conclude that service quality and visitor experience directly affect visitor satisfaction significantly, with path coefficients of respectively 0.45 (p < 0.01) and 0.38 (p < 0.05). Both factors, however, did not directly affect on revisit intention, with path coefficients of 0.12 (p > 0.05) and 0.15 (p > 0.05), respectively. Visitor satisfaction, on the other hand, significantly influences revisit intention, with a path coefficient of 0.52 (p < 0.01), indicating that higher satisfaction increases the likelihood of revisiting the destination. Notably, service quality and visitor experience indirectly affect revisit intention through satisfaction, with effect sizes of 0.23 and 0.21, respectively.

Analog Rice from Pedada Fruit Composite Flour as Functional Food with Low Glycemic Index

Diella Trisna Ayuningtyas — 2025-12-08

This study aims to determine the effect of composite flour proportion pedada fruit, white corn, and soybean flours as well as the addition of GMS on the physicochemical and organoleptic properties of analog rice as functional food that is safe for people with Diabetes Mellitus. This study was arranged in a factorial completely randomized design consisting of two factors with nine treatment combinations and three replications. Factor 1 was the proportion of flour materials pedada fruit-white corn-soybean (5%-75%-20%, 10%-70%-20%, 15%-65%-20%). Factor 2 was GMS addition (1%, 2%, 3%). The data was analyzed using ANOVA at the 5% level and continued with the Duncan Multiple Range Test (DMRT). The results showed that the best treatment was the A1B1 formulation consisting of 5% pedada fruit flour, 75% white corn flour, 20% soy flour and the addition of 1% GMS produced analog rice with organoleptic characteristics of color getting a value of 3.48 (like), aroma 2.92 (neutral), texture 2.76 (neutral), and taste 3 (neutral), antioxidant content of 47.73%, in vitro glycemic index of 42. The results of the RVA analysis showed that formulation A1B1 had a pasting temperature of 94.8°C, peak viscosity 184 cP, hold viscosity 183 cP, final viscosity 332 cP, breakdown 1 cP, setback 149 cP.

Irrigation Deficit for Ciherang Rice Variety as a Benchmark for Developing Upland Rice Cultivation Systems

Sri Widata — 2025-12-08

This study aims to evaluate the agronomic response of Ciherang rice plants during the vegetative and generative phases under deficit irigation conditions, as a benchmark for cultivation in dry land. This study used a factorial Completely Randomized Design with two factors. First, the level of water efficiency consisting of three levels, namely 300 ml, 600 ml, and 900 ml; second, the ratio of cattle manure and urea fertilizer also consisting of three levels, namely 80:20, 50:50, and 20:80. The observed variables include vegetative phase parameters, such as plant height, number of tillers, and dry weight of biomass, as well as generative phase parameters, such as percentage of filled grains and weight of filled grains per clump. The results showed that there was a significant interaction between water efficiency and fertilizer ratio during the generative phase, but no similar interaction was found during the vegetative phase. Furthermore, the combination of 600 ml water treatment with a 50:50 fertilizer ratio produced the highest percentage of filled grains and weight of filled grains. These results indicate that Ciherang rice can grow well under efficient water conditions, making it potentially suitable for cultivation in dry land.

Nondestructive Prediction of Oil Palm Fruit Quality During Processing Delays Using Electrical Impedance Spectroscopy

Arief Al Akbar — 2025-12-08

Nondestructive prediction of palm fruit quality is needed to monitor changes in palm fruit quality during processing delays. This study aims to develop a method for predicting the chemical quality of palm fruit during processing delays using the Electrical Impedance Spectroscopy (EIS). The electrical impedance of palm fruit were measured at frequencies of 50 Hz to 1 MHz and followed by the determination of free fatty acid (FFA) and moisture content using chemical methods. The best initial treatment for impedance spectrum data in this study was Standard Normal Variate (SNV) and Baseline. The results of this study indicate that the PLS method outperforms PCR in predicting FFA and moisture content. The best prediction for free fatty acid content was using the SNV pre-treatment and component factor 7 with a value of r = 0.87; SEC = 2.75%; SEP = 2.82%; CV = 23.81%; RPD = 1.94 and consistency of 97.75%. The best prediction for moisture content was obtained using the Baseline initial treatment and component factor 15 with a value of r = 0.97; SEC = 3.65%; SEP = 3.82%; CV = 28.24%; RPD = 1.91 and consistency of 83.24%. The developed electrical impedance and PLS methods can be used to predict free fatty acid content and moisture content of oil palm fruit during processing delays.

Growth Improvement of Palm Oil Seedling using Biochar from Oil Palm Empty Fruit Bunch and Rubber Wood

Seldi Prayoga — 2025-12-09

Agricultural wastes biochar can be used to support the growth of oil palm seedlings. This study aims to assess the effectiveness of biochar pellets made from oil palm empty fruit bunches (OPEFB) and rubber wood wastes on the growth of oil palm seedlings. The research was conducted in the greenhouse using a factorial complete randomized design with two treatment factors, namely the type of biochar pellets (OPEFB and rubber wood) and doses of 0%, 5%, 10% with 10 replications. Observation included plant height, stem diameter, number of leaves, and total dry weight. The results showed that biochar pellet application had a significant effect on plant growth, especially at a 10% dose, which increased plant height, stem diameter, number of leaves, and dry weight compared with the control. The 10% dose of OPEFB biochar pellet produced a plant height of 21.4 cm, stem diameter of 3.64 cm, and number of leaves of 8 strands, while the same dose of rubber wood biochar pellet produced a height of 15.67 cm, diameter of 3.64 cm, and number of leaves of 6.67 strands. OPEFB biochar pellet showed higher results than rubber wood biochar, but at the same dose, the difference is minor. These results indicate that biochar pellets from agricultural waste have the potential to effectively support the growth of oil palm seedlings in an environmentally friendly manner.

Effect of Seed Bulb Cutting Size and Planting Media Volume on the Growth and Yield of Shallot (Allium ascalonicum L.) under a Hydroponic Wick System

Muhammad Fahri Rizaldi — 2025-12-09

Shallots (Allium ascalonicum L.) are cultivated as a high economic value agricultural business. Cutting the tip of the seed bulb can stimulate, accelerate and synchronize plant growth. In hydroponic cultivation, the volume of planting media is an important component that needs to be considered. This research was conducted at the Greenhouse Hydroponic Farm Lamongan, Lamongan District, Lamongan Regency, East Java. Split plot design (RPT) or split plot design in a Completely Randomized Design (CRD) with the main plot (main plot) the volume of planting media (U) with 3 levels: 10cm (U1), 15cm (U2), 20cm (U3) and sub plots (sub plots) are the size of the cutting of the seed bulbs (P) with 4 levels: not cut (P0), cut 1/4 (P1), cut 1/3 (P2), cut 1/2 (P3). It was found that the treatment of the size of the cutting of the seed bulbs affected the vegetative and generative variables. Meanwhile, the treatment of planting media volume affects generative variables, especially on the number of harvested bulbs per box and the weight of harvested bulbs per box. The most optimal interaction between the combination of the size of cutting seed bulbs and the volume of planting media occurs at the size of cutting seed bulbs of 1/4 part and the volume of planting media of 10 cm, which is able to increase the weight of harvested bulbs per clump.

Design of Fruit Fly Trap ApelB Using a Microcontroller and Sensor System Powered by Solar Photovoltaic

Masrur Alatas — 2025-12-09

Indonesia’s vast horticultural land faces serious threats from Bactrocera fruit fly infestations, a type of fruit fly in the Tephritidae family that causes rotting plants, reducing the quality of plantation and agricultural products, and even crop failure. The purpose of this study was to design a fruit fly (Bactrocera) trap ApelB version 1.1, using the Cockcroft-Walten Circuit, Methyl Eugenol, PIR HC-SR501 sensor, Arduino Uno ATmega328P, powered by electricity from a Solar Power Plant/System (PLTS) with a panel capacity of 10 Wp, Solar Charge Controller 10 A and a 14.8 V 2.5 Ah battery. The ApelB version 1.1 test method on agricultural land for 24 hours used methyl eugenol to attract fruit flies to enter the trap. Electricity from the PLTS functions to eradicate fruit flies that land on the electric net trap. The findings of ApelB version 1.1 successfully attracted, detected through sensors, and eradicated fruit flies with electric shocks. The capture rate was 80% in lab tests, while corn and chili field trials caught an average of 148–150 fruit flies. ApelB version 1.1 can suppress attacks and fruit fly populations, with a PLTS system and energy storage battery. This tool is guaranteed to operate 24 hours automatically.

Preservation and Packaging Methods to Extend the Shelf Life of Fresh Lontar (Borassus flabellifer L.) Pulp

Dewi Pratiwi Sasmito — 2025-12-09

Lontar is a palm with fruits having a various important biomolecules containing proteins, carbohydrates, vitamins, and minerals, which are beneficial to human health. The shelf life of lontar fruit pulp is generally limited to approximately 1–2 days. The objective of this study was to analyze the effect of water amount and citric acid concentration combining with packaging types and temperature ranges on the quality of fresh lontar fruit pulp and the shelf life of the pulp. The research used Response Surface Methodology with a Central Composite Design as the design model to find the best combination of water and citric acid concentration. The selected combination was applied in preservation treatment with polypropylene and nylon packaging under storage temperatures of 15 °C and 25–28 °C. The quality parameters observed included brightness, hardness, pH, and total dissolved solids, as well as organoleptic tests. The optimization results indicated that the optimal ratio of water to citric acid concentration was 40 ml to 0.2%. Cold storage significantly extended the shelf life of lontar fruit pulp to 6 days, compared to just 3 days at room temperature. The organoleptic test results showed that PP packaging received a higher level of favorability compared to nylon packaging.

Flood Mitigation Priority Strategy to Reduce Community Vulnerability in the Downstream Area of the Setail Watershed, Banyuwangi

Gigik Nurbaskoro — 2025-12-09

Floods that repeatedly occur in the downstream area of the Setail Watershed have caused significant damage to infrastructure, community livelihoods, and social systems in the region. This condition demands the implementation of effective and sustainable mitigation strategies to reduce flood risks and impacts. This study aims to determine priority flood mitigation strategies to reduce community vulnerability in the downstream area of the Setail Watershed. The identification of mitigation criteria was first conducted through interviews with flood-affected communities to capture relevant local factors. These criteria were then discussed with disaster mitigation experts and stakeholders, and the results of the questionnaires were analyzed using the Analytical Hierarchy Process (AHP) method to evaluate and rank the mitigation strategies. The results show that the three main priority strategies are flood risk mapping with a score of 0.22, community education and awareness with a score of 0.18, and zoning and spatial planning with a score of 0.15. These strategies are expected to serve as the basis for the preparation of local government action plans to minimize future flood impacts and enhance community resilience and well-being.

Effect of Packaging on Protein Content, pH, and Sensory of Probiotic Tempeh Juice During Cold Storage

Nur Aini Sahara — 2025-12-10

Tempeh juice with probiotics is considered as functional probiotic foods with health benefits. This study aimed to evaluate the effect of packaging type (glass bottle and aluminum foil), and cold storage duration on chemical, microbial and sensory properties of probiotic tempeh juice. The research used a two-factorial Randomized Complete Block Design with three replications. ANOVA was used to analyze the data and it was followed by DMRT test at 5% significance level. The results showed that storage duration had no significant effect on viscosity and other chemical analysis, but was significant on sensory attributes of color, aroma, taste, and overall acceptability. Protein decreased on the 8^th day probably due to protein hydrolysis by microbial activity, but increased on the 12^th day of storage due to the accumulation of microorganism cell walls during storage. However, sensory changes included a paler color, a stronger fermentation aroma, an acidic alcoholic taste, and overall acceptance was acceptable. It was concluded that glass bottle packaging was more effective in maintaining the stability of protein content, pH, and sensory of probiotic tempeh juice beverage compared to the aluminum foil standing pouch with a spout, with the estimated shelf life was 8 days in cold storage.

Investigation of Drying Time and Final Moisture Content of Arabica beans in a Solar Drying Chamber

Rendi Ramdhani — 2025-12-10

Drying is a critical stage that affect directly the quality, storability, and market value of Arabica coffee beans. The objective of this study was to investigate the performance of a solar drying chamber integrated with a thermal collector and phase change material (PCM), operated under a constant airflow velocity of 9.2 m/s. Arabica beans of 1500 g were dried over two observation days, with chamber temperatures ranging from 40 °C to 46.5 °C and peak solar radiation of 1122 W/m². The results showed that the system effectively maintained thermal stability and drying performance despite fluctuations in solar input. The analysis revealed at Day 2 achieved a higher and faster moisture reduction due to improved solar conditions and absorber efficiency, with drying rates peaking at over 42 g vapor per hour in the third hour. In contrast, at Day 1 the drying rate peaked in the third hour at approximately 22.45 g vapor/h. Day 1 exhibited a more stable but slower drying trend. Overall, the system successfully reduced the beans’ moisture content to below 12.8% in within under 14 hours, with Tray 2 delivering the most consistent results. These findings demonstrate that the integration of solar thermal energy, PCM, and forced convection application significantly improved drying efficiency and reliability, offering a sustainable alternative for post-harvest processing, especially in regions with variable weather conditions.

Biopesticides and Refugia Implementation Increasing the Population and Diversity of Natural Enemies in Rice Fields based on Ecology

Muhammad Izza Kurniawan — 2025-12-10

The diversity of natural enemies of insects is influenced by the availability of microhabitats and food sources, which can be increased through the use of refugia. Intensive use of pesticides in conventional agricultural systems has resulted in a decline in the diversity of natural enemies that play an important role in biological control of pests. This study aims to identify the types, roles, and populations of natural enemies of pests and determine the level of natural enemy diversity including the species diversity index, species evenness, species richness, and dominance in rice fields using integrated and conventional farming systems. Data collection methods were carried out through a combination of direct observation, insect nets, yellow traps, light traps, and identification of insect morphospecies using a digital microscope and supporting literature. The identification results showed 7 orders and 21 genera of natural enemies with a total of 4,679 individuals in integrated fields and 2,792 individuals in conventional fields. The species diversity index (H’=2.11), evenness (E’=0.69), species richness (R’=2.37), and dominance (C’=0.18) indicated that the integrated system was more supportive of biodiversity. Ecological engineering through refugia has been shown to increase the population diversity of natural enemies, thereby strengthening biological control in rice ecosystems.

Effect of Ultrafine Bubble Additives on the Properties of B-35 Diesel Fuel

Husen Asbanu — 2025-12-10

Improving the quality of B-35 biodiesel fuel is crucial, especially in distillation and flash point parameters that affect performance and safety. The objective of this study was to analyze the effect of oxygen ultrafine bubble application on the fuel characteristics of B-35 including cetane number, viscosity, density, flash point, distillation, and cloud point. Tests were conducted according to ASTM standards: D86 (distillation), D93A (flash point), D613 (cetane number), D445 (viscosity), D4052 (density), and D5773 (cloud point). The treatment was performed by injecting oxygen ultrafine bubble at a rate of 1, 3, and 5 l/min into 1.5 liters of fuel for 10–60 minutes. The results showed the highest distillation temperature of 339.7 °C at 1 l/min and 10 minutes, while the lowest temperature of 330.9 °C was achieved at 5 L/min and 60 minutes (control: 341.6 °C). The highest flash point of 72 °C occurred in the low oxygen injection rate and short duration, while the lowest was 64.5 °C in the high rate and long duration. The treatment increased cetane number from 58.6 to 60.8. The decrease in viscosity and density was insignificant but remained within standard limits. The cloud point decreased from 7.1 °C to 5 °C. UFB oxygen addition shows significant potential in improving the quality and combustion efficiency of B-35 fuel

A Financial Feasibility Analysis and Supply Chain of XYZ Rice Polishing Business

Agus Priyanto — 2025-12-11

The increasing demand for premium rice in Indonesia has opened up opportunities for rice polishing businesses to increase added value and competitiveness. Challenges such as rising raw material prices, increased operational costs, and process efficiency have become obstacles in maintaining the sustainability and competitiveness of these businesses. This study aims to analyze the financial feasibility and supply chain structure of the rice polishing business at UD XYZ, ABC Regency, South Sulawesi. A case study method was used with a quantitative and qualitative descriptive approach. The financial analysis included NPV, IRR, B/C ratio, PI, ROI, payback period, and sensitivity analysis. The supply chain structure is analyzed through product, financial, and information flow mapping. The results show that UD XYZ is a small-scale business and is financially feasible to operate with a positive NPV, IRR higher than the benchmark interest rate, B/C and PI greater than 1, profitable ROI, and good financial indicators, although it is vulnerable to variable cost increases of more than 2%. The supply chain is relatively short, from rice milling to end consumers. These findings have important implications for business actors and policymakers in the development of the rice polishing industry in production centers.

Mathematical Modeling for Climate-Based Optimization of Rice Planting Schedules

Moh Yusuf Dawud — 2025-12-11

The stability of rice production is greatly influenced by the dynamics of climate variability that changes rapidly and is unpredictable. This study developed a climate-based planting scheduling model that utilizes daily climate data and annual production data for the period 2016–2024. The predictive model was built through multiple linear regression to examine the effects of temperature, rainfall, humidity, and wind speed on crop yields and ARIMA to project climate and rice production until 2029. Data were obtained from BMKG, BPS, and related regional agencies, then processed to produce an adaptive planting schedule. The regression results showed high accuracy with R² = 0.99, Adjusted R² = 0.961, MAE = 5.980, and RMSE = 6.770. Rainfall showed a negative effect (p = 0.025) on rice production. The optimization model produced the two most profitable planting months each year and provided more stable yields than conventional planting patterns. Five-year production projections show fluctuations influenced by climate conditions, including a sharp decline in 2027 and a rebound in 2029. The development of an adaptive schedule model allows for alternative decision-making in areas vulnerable to climate change.

Ergonomic Redesign of Farm Tools to Reduce Musculoskeletal Disorders among Nigerian Farmers

Hyginus Unegbu — 2025-12-11

The persistent prevalence of musculoskeletal disorders (MSDs) among Nigerian smallholder farmers remains a critical occupational health challenge, largely due to the prolonged use of poorly designed manual farm tools. This study investigated the ergonomic redesign of traditional hoes and cutlasses using a simulation-augmented, mixed-method experimental design aimed at reducing biomechanical stress and enhancing task efficiency. A total of 220 farmers (aged 18–65, with gender-balanced representation) from southwestern Nigeria participated in the study, ensuring population diversity and practical relevance. Redesign was guided by computer-aided design (CAD) modelling, finite element analysis (FEA), and field-collected anthropometric datasets. Key ergonomic indicators included Rapid Entire Body Assessment (REBA) for postural risk, surface electromyography (EMG) for muscle fatigue, task completion time, and the Borg Rating of Perceived Exertion (RPE) for perceived effort. Results showed statistically significant improvements (p < 0.01) across all performance metrics. REBA scores decreased from high to moderate/low risk categories, EMG activity reduced by over 30%, and task completion time improved by 33–36%. RPE scores were halved, indicating increased user comfort. Effect sizes (Cohen’s d > 1.2) confirmed the strong practical impact of the redesigned tools. While limited by short-term field exposure and a regional study scope, the research offers a replicable model for ergonomic tool development in informal agricultural systems. The findings support actionable interventions such as standardised tool design guidelines, local manufacturing protocols, and farmer training programmes. This study demonstrates that ergonomic simulation using CAD and biomechanical tools can lead to meaningful reductions in MSD risk, improved task performance, and higher usability in resource-limited farming environments.

Logging Safety Practices of Chainsaw Workers in the Indonesian State Forest Concession

Ahmad Luthfi Syauqi — 2025-12-11

The forestry industry outside Java continues to rely on chainsaw-based logging in natural forests, a technique that involves significant safety risks due to the size of harvested trees, machine hazards, and challenging environmental conditions. These risks highlight the need for skilled operators and effective Occupational Safety and Health (OSH) systems. This study was conducted at two Indonesian State Forest Concessions in East Kalimantan and examined OSH implementation among chainsaw operators. Data were collected through questionnaires with both qualitative and quantitative components, field observations, interviews, and analysis of company documents, including work plans and safety procedures. The results showed that operator awareness of OSH was very high (85.94%), and support and guidance from managers and foremen also strongly influenced compliance (75.97% and 76.81%, respectively). However, barriers remained (49.46%), particularly in the form of incomplete Personal Protective Equipment (PPE), operator discomfort when using certain PPE, and the absence of structured training. These shortcomings indicate a gap between policy and practice. Addressing these issues requires companies not only to provide complete and comfortable PPE but also to enhance training and actively enforce safety protocols. Strengthening these measures would improve both worker safety and the overall sustainability of forest operations.

Competitiveness of Indonesian Cocoa in Major Export Destination Countries Using Porter’s Diamond Model Approach

Risqi Firdaus Setiawan — 2025-12-15

Indonesia is one of the world’s leading cocoa producers, yet its contribution to global value-added cocoa exports remains relatively low. This structural gap highlights the need to evaluate not only production capacity but also the competitiveness of Indonesian cocoa in international markets. This study aims to evaluate the competitiveness of Indonesian cocoa exports in four main destination countries: India, China, Malaysia, and the Philippines. Data sources were obtained from UM Comtrade, ITC Trademap, International Cocoa Organization (ICCO), and BPS. The analysis was conducted by combining methods of the Revealed Comparative Advantage, Export Competitiveness Index, and the Porter's Diamond Model. The results show that Indonesia still has a comparative and competitive advantage in several markets, especially India. The average RCA value was 10.41 in Malaysia, 9.42 (China), 5.40 (India), and 3.97 (the Philippines). Meanwhile, the ECI value is greater than one, namely 1.21 (India), 1.09 (China), 1.08 (Malaysia), and 1.05 (the Philippines). These advantages, however, are volatile and highly dependent on natural resource factors. Weak domestic demand, inconsistent quality standards, limited downstream industry capacity, and fragmented policy coordination remain key structural challenges. This research emphasizes that strengthening competitiveness not only requires the maintenance of comparative advantage, but also its transformation into a sustainable competitive advantage through institutional reform, cross-sector policy integration, and value-added product innovation.

Comparative Effectiveness of Organic Fertilizer Types on Soybean Growth, Yield, and Soil Health in Sustainable Cultivation Systems

Indra Gunawan — 2025-12-15

Limitations in productivity and adverse impacts of chemical fertilizers highlight the need for sustainable solutions in soybean cultivation in Indonesia. This study aims to evaluate the effectiveness of organic fertilizers as an alternative to chemical fertilizers in sustainable agriculture-based soybean cultivation. The experimental method employed a Completely Randomized Design (CRD) with six treatments: control (no fertilizer), chemical fertilizer, goat manure, compost, biochar, and a combination of POC + compost. The parameters observed included plant height, number of effective root nodules, yield components (number of pods, weight of 100 seeds, yield per polybag), as well as changes in soil chemistry after harvest. The results showed that the treatment of goat manure (P2) and a combination of POC + compost (P5) gave the best results in improving soybean growth and yield. Both also showed significant improvements in soil pH, C-organic content, total nitrogen, and availability of P and K. In addition to increasing crop yields, organic fertilizers have also been proven to support increased soil microbial activity through the formation of effective root nodules. Thus, organic fertilizers have proven to be an effective and environmentally friendly alternative in replacing chemical fertilizers. The use of organic fertilizers can promote productive, efficient, and sustainable soybean farming.

Formulation of Ready-to-Use Fish Food Based on Mackerel (Scomberomorus) and Catfish (Clarias gariepinus)

Ratna Komala Putri — 2025-12-15

This study developed Ready-to-Use Fish Food (RUFF) as a high-energy, high-protein recovery food for children under five with severe acute malnutrition, using mackerel and catfish powders as animal protein sources. Four RUFF variants were formulated with skim milk powder, mackerel powder, catfish powder, and a mixture of both fish powders. Nutritional analysis included moisture, ash, protein, fat, carbohydrates, and energy content, which were compared to Codex Alimentarius (CXG 95-2022) standards. Protein ranged from 2.31 to 4.61 g/100 kcal, fat from 5.64 to 6.25 g/100 kcal, carbohydrates from 6.79 to 9.44 g/100 kcal, and energy from 524 to 550.49 kcal/100 g, meeting FAO/WHO criteria for therapeutic foods. The sensory acceptability was assessed using a hedonic test with toddlers aged 2 to 5 years using a Balanced Incomplete Block Design. Scores ranged from 1 (like), 2 (neutral), and 3 (dislike), analyzed by ANOVA and Tukey’s test. The mixed fish powder variant had the least preference (mean score 2.08, neutral), while catfish, mackerel, and skim milk variants were liked (scores 1.23 to 1.83). Results confirm that these RUFF variants are nutritionally adequate and well accepted, supporting their use as an effective alternative to RUTF for malnourished toddlers.

Utilization of Banana Pseudostem Biomass Waste and Coconut Pulp as Briquettes for Alternative Energy Sources

Mellyta Uliyandari — 2025-12-16

This study aims to utilize banana pseudostem and coconut pulp waste as raw materials for biomass briquettes, evaluate their physical and thermal characteristics, and assess their potential as alternative fuel sources. The research methods included drying, grinding, mixing, molding, and briquette testing. Characterization was conducted through hardness testing using a digital sclerometer, morphological and particle size analysis using a digital microscope, calorific value measurement using a bomb calorimeter, and thermal degradation analysis using Thermogravimetric Analysis (TGA). The hardness test showed that pure banana pseudostem briquettes had the highest compressive strength according to the P3HH standard, while the addition of coconut pulp tended to reduce it. Increasing the proportion of coconut pulp produced larger average particle sizes, affecting briquette porosity. The highest calorific value, 16,829.73 J/g, was obtained from a 50:50 composition, indicating that the oil and lignin content in coconut pulp contributes to combustion energy. TGA analysis revealed that briquettes with higher banana pseudostem content exhibited greater heat resistance, while those with more coconut pulp ignited faster and left less residue. In conclusion, briquettes made from banana pseudostem and coconut pulp can be used as an alternative solid fuel, with compositions adjustable according to the desired energy output and combustion characteristics.

The Effect of Water Application Levels on the Nutritional Value of Maize (Zea mays L.) Forage under Biochar-Amended Vertisol Soil in Kupang Regency, East Nusa Tenggara

Masria Masria — 2025-12-16

This study aimed to examine the effect of different water levels on the growth and nutritional value of maize (Zea mays L.) forage grown on Vertisol soil amended with corncob biochar. The research was conducted in Oesao Village, Kupang Regency, East Nusa Tenggara. Biochar was produced by pyrolyzing corncobs at 300–600 °C and applied in the soil at 6% by weight. The experiment used a Completely Randomized Design with four water levels (K1 = 100%, K2 = 90%, K3 = 80%, K4 = 70% of field capacity) and six replications for measuring plant growth. Soil property and proximate analyses were conducted using composite samples with three replications. Chemical properties of biochar, initial and post-treatment soil properties, plant growth (height, number, and leaf area), and forage nutritional quality were analyzed. The results showed that treatment K4 improved soil chemical properties including organic carbon, P₂O₅, cation exchange capacity (CEC), and exchangeable cations. Treatment K1 produced the best vegetative growth with the most leaves, leaf area, and plant height. Meanwhile, treatment K3 resulted in the best forage nutritional quality, with the highest nitrogen, crude protein, and crude fat content and the lowest crude fiber content. Overall, treatment K3 was considered the most optimal because it balanced plant productivity and forage quality.

Assessment of Carbon Capture and Storage in Plantation and Garden Agroecosystems in Tuntang Hulu Sub-Watershed

Rosita Mustikasari — 2025-12-16

Agroecosystems such as gardens and plantations play a crucial role in climate change mitigation through carbon capture and storage (CCS). This study aimed to analyze the carbon storage potential of these two agroecosystem types in the Tuntang Sub-Watershed and to examine the factors influencing it. A quantitative-descriptive approach was employed, involving biomass measurement both above and below round, along with analyses of soil physical and chemical properties at 41 sampling points. Results showed that the average CCS capacity in plantation areas reached 380.51 tons/ha, slightly higher than that of gardens at 333.30 tons/ha, although the difference was not statistically significant. Contributing factors to carbon storage capacity included vegetation type, soil pH, soil texture, and bulk density. Plantations were dominated by perennial woody crops producing higher biomass, whereas gardens were more commonly planted with annual crops. Therefore, well-planned vegetation management, particularly mixed agroforestry systems, has the potential to enhance CCS efficiency. These findings serve as an important foundation for planning sustainable agroecosystem management as a strategy for climate change adaptation and mitigation.

Shelf Life Estimation of Taro Flour Packaged in Polypropylene (PP) and High-Density Polyethylene (HDPE) Using The Arrhenius Approach

Shafira Pradyta — 2025-12-16

Taro flour stored for an extended period tends to experience a decline in quality. Therefore, determining the optimum storage period is essential. The Accelerated Shelf Life Testing (ASLT) method using the Arrhenius model was applied to estimate the shelf life of taro flour. The research on taro flour was carried out in three stages. The first stage involved the production of taro flour. The second stage included monitoring changes in quality during the storage period. The third stage focused on estimating the shelf life of taro flour packaged in polypropylene (PP) and high-density polyethylene (HDPE) materials. Drying and milling taro tubers produced taro flour with a final moisture content of 10%. During the storage period, observations were made on moisture content, whiteness degree, and protein content. Shelf life estimation was conducted using the Arrhenius model, with the selection based on a critical quality parameter protein content. The results indicated that the estimated shelf life of taro flour based on protein content in PP and HDPE packaging at 25 ℃ was 223 days and 285 days, respectively. Meanwhile, at storage temperature of 28 ℃, the shelf life of taro flour in PP and HDPE packaging was estimated to be 147 days and 183 days, respectively.

The Effect of Solar Radiation on the Performance of Tilted Bifacial Photovoltaics

Luthfi Saepulloh — 2025-12-16

A solar panel technology known as bifacial photovoltaics (PV) allows sunlight to reach both the front and rear of the module. The purpose of this study is to assess how temperature and solar radiation affect tilt-mounted bifacial photovoltaic systems' performance in tropical regions, particularly in Indonesia. The experiment was conducted in an outdoor location in Bandung. The bifacial PV modules were installed a 15˚ tilted angle facing north, with the PV modules positioned 1.2 meters above ground level on an asphalt base. The experiment was conducted under three different weather conditions: sunny, cloudy, and partly cloudy. Based on the experimental results under sunny conditions, the average solar radiation, surface temperature, and PV power generated were 923.8 W/m², 51.1 ℃, and 245.7 W, respectively. Under cloudy conditions, the average solar radiation, surface temperature, and PV power generated were 458.9 W/m², 43.1 °C, and 91 W, respectively. Meanwhile, under partly cloudy conditions, the average solar radiation, surface temperature, and PV power output are 661.6 W/m², 50.2 °C, and 215.8 W, respectively. The highest efficiency was achieved during partly cloudy weather at 15.85%, followed by sunny weather at 11.99%, and the lowest during cloudy weather at 7.73%.

Effect of Land Use on Soil Water Storage in the Effective Depth (0–60 cm) Using the Water Balance Method

Muara Dhika — 2025-12-16

Land use changes significantly impact groundwater storage, which is crucial for maintaining ecosystem balance and supporting agriculture. This study aims to evaluate groundwater storage capacity across various land uses in the Gunting Sub-watershed, Wonosalam District, Jombang Regency, East Java. Field surveys and soil sampling were conducted across three land use types: pine-coffee agroforestry, pine monoculture, and annual crops at effective soil depths (0-60 cm). The study was conducted using a water balance method and lasted for one year, from August 2022 to July 2023. Water balance components consisting of effective rainfall, surface runoff, percolation, and evapotranspiration, as well as soil properties such as organic carbon content, porosity, and texture, were analyzed. The results showed that agroforestry had the highest water storage (370,863.44±176.67 mm/year), followed by pine monoculture (307,153.36±229.98 mm/year), and annual crops (239,497.30±222.26 mm/year). Statistical tests showed that differences between land uses were not significant (p > 0.05). Organic matter content was the dominant factor influencing soil water storage (R² = 0.9189), followed by porosity (R² = 0.3019) and clay fraction (R² = 0.0172). All land use types showed a positive water balance throughout the year, with peak water storage occurring in February–May.

Artificial Neural Network Backpropagation Method for Predicting Soil Nutrient Content

Witaningsih Witaningsih — 2025-12-29

Monitoring soil nutrient levels such as nitrogen (N), phosphorus (P), and potassium (K) is essential to support fertilizer efficiency and sustainable agricultural land management. However, commonly used laboratory-based analytical methods are time-consuming and costly. Therefore, alternative approaches that are more practical and efficient are needed. This study aimed to develop an Artificial Neural Network (ANN)-based system for predicting soil nutrient levels using soil physical parameters, namely pH, temperature, moisture content, and electrical resistance, as input variables. Data were collected from red-yellow podzolic soil subjected to different fertilization treatments. After normalization, the data were trained using an ANN model with four input nodes, two hidden layers (each consisting of five nodes), and one output node, employing the backpropagation algorithm and evaluating 27 combinations of activation functions. The training results showed coefficients of determination (R²) of 0.9642 for nitrogen, 1.0000 for phosphorus, and 0.9996 for potassium, with RMSE values of 0.0107, 10.5386, and 0.016457 and RRMSE values of 8.5048%, 0.79786%, and 1.581111%, respectively. During validation, R² values of 0.7218 (nitrogen), 0.6479 (phosphorus), and 0.6137 (potassium) were obtained. Nitrogen prediction exhibited good accuracy (RMSE 0.0222; RRMSE 15.54%), potassium prediction showed moderate accuracy (RMSE 0.2963; RRMSE 28.46%), while phosphorus prediction resulted in relatively high errors (RMSE 1066.77; RRMSE 80.98%), indicating the need for further model development.

Development of Web-Based Application for Analysis and Design of Steam Power Plant System Parameters Using Biomass Fuel

Offianda Kurniawan — 2025-12-30

The process of physically prototyping a power generation system is time consuming and costly. Adopting the concept of Digital Twin Technology offers a solution to improve the efficiency in prototyping processes. This study aims to develop a web-based application called ThePOCI for thermal analysis of steam power plant systems working with ideal Rankine cycle, and to evaluate the accuracy of the developed application. The ThePOCI thermal system application consisted of two main modules: Steam Power Plant Design and Combustion Analysis. Validation of the Combustion Analysis module revealed the largest calculation errors in the thermal-based model for variables including flue gas temperature (13.08%), temperature of boiler exit working fluid (16.93%), and turbine power (10.49%), yet all fall within the low error range. Validation of the Steam Power Plant Design module produced deviations of ideal and actual operating conditions of 2.22% and 0.88%, respectively, categorized as highly accurate. The validation results confirm that ThePOCI can accurately simulate the physical system of a steam power plant based on the ideal Rankine cycle. System emission calculations indicate potential for further research on the use of Calliandra biomass in Organic Rankine Cycle (ORC)-based steam power plants, identified as the fuel producing the lowest emissions at 3,742.20 kgCO₂e/kW.

Mechanisms and Application of Fruit and Vegetable Shelf Life Extension Using 1-MCP, NO, and Melatonin: Systematic Review

Melati Pratama — 2025-12-30

Fruits and vegetables are perishable commodities after harvest. Fruit and vegetable damage occurs due to post-harvest metabolic processes that can result in the formation of ROS and ethylene, bacteria, fungi, chilling injury and mechanical damage (wounds). New technologies were discovered to inhibit ripening, aging and post-harvest fruit damage, namely the use of Methylcyclopropene (MCP), Nitric Oxide (NO) and Melatonin. The purpose of this paper is to analyze the mechanism of the three inhibitors, their applications, advantages and disadvantages so that they can be used effectively and efficiently. The method used is systematic review, data are collected and analyzed systematically. A review of 106 articles shows that MCP, NO, and melatonin have different mechanisms. MCP works by inhibiting ethylene receptors, NO through four pathways (S-nitrosylation, limiting SAM formation, forming MACC, binding NO-ACC-ACC), and melatonin through four pathways (slowing ripening, reducing cold damage, as an antioxidant, as an antibacterial agent).