Kjeldahl Method Research Articles

Investigation of parameters in restaurant food waste for use as poultry rations

One way to use food industry wastes is to feed the livestock and poultry. Applying appropriate management methods for the optimal use of agricultural waste in the preparation of livestock and poultry feed increases productivity and reduces damage to agricultural and conversion industries and the use of new resources in animal and poultry feed. In this paper, in order to investigate the possibility of recycling food waste as poultry feed, the waste produced in a restaurant has been used. The parameters of fat percentage were measured using Soxhlet extractor, percentage of dry matter using the oven, percentage of protein in it using Kjeldahl method, and also the percentage of calcium and phosphorus with the standard beard. Comparing them with the usual diet used in poultry feed shows that the average values ​​of calcium, protein, and fat content of food waste are 0.14%, 5.65%, 7.34% higher than the average diet of poultry, respectively. Also, the average amount of phosphorus and dry matter of food waste is 0.48% and 60% less than the average diet of poultry, respectively.

Effects of vitamin A, C, E and Selenium on chemical constituents of feathers of quail

The present study is carried out to analyze the trace elements copper, zinc, iron, manganese, phosphorus, magnesium, calcium and sodium by atomic absorption spectrometer, crude protein by Kjeldahl method and essential and non-essential amino acids by reverse phase high performance liquid chromatography (RR-HPLC) from feather of quail (coturnix coturnix) before the administration of four ACES antioxidant vitamins A, C, E and selenium. Thereafter these four ACES will be mixed with the quail feed and the quail will be kept on blended feed for a period of one month. The feather of vitamin administered quail were analyzed for the same mineral, protein and amino acid constituents.

Effects of Indigenous and Non-Indigenous Arbuscular Mycorrhizal Fungi on Growth and Plant Nutrient Uptake by Terung Asam (Solanum lasiocarpum Dunal)

Terung asam (Solanum lasiocarpum Dunal) is a native fruit vegetable that is gaining interest as a commercial crop in Sarawak and Malaysia. Malaysia is covered by soils that are highly weathered, acidic, and low in fertility and depend on chemical fertilisers to promote good plant growth. Alternative means to reduce dependency on chemical fertiliser, for example arbuscular mycorrhiza fungi (AMF), must be sourced. Very few research on terung asam has been documented particularly on nutrients uptake. The objectives of this research were to investigate the effect of indigenous and non-indigenous AMF on nutrient uptake by terung asam. A greenhouse experiment was conducted consisting of three treatments namely control (T1), indigenous AMF (T2), non-indigenous AMF (T3). The treatments were arranged in a complete randomised design with four subsamples and four replicates. Thirty-day-old seedlings were transplanted and measured for their heights and stem diameters for 90 days. Fresh and dry shoot and root weights were taken during harvesting. Plant nutrient analyses were conducted using Kjeldahl method for total N, single ashing for P and single ashing and double acid for K, Ca and Mg. The results revealed the addition of AMF spores at 200 spores per pot, increased plant height by 13 to 33% and stem diameter by 5 to 25% and more leaves were retained by T3 plants at harvesting. T3 recorded higher fresh shoot (11.27%) and dry shoot (14.98%) as well as fresh root (23.67%) and dry root (22.77%) weights than T1 plants. Addition of AMF in treatments T2 and T3 promoted better nutrient uptake by aboveground and belowground biomasses particularly for K, Ca and Mg. T3 was superior in terms of the nutrient uptake for most nutrients. AMF used in T3 showed better results as the AMF spores were proven effective in promoting plant growth while AMF used in T2 were obtained from the field and untested. The findings of this study showed the potential of indigenous and non-indigenous AMF in promoting growth and nutrient uptake by terung asam plants.

Pembuatan Konsentrat Protein Ampas Kelapa (Cocos nucifera L.) Bebas Lemak pada Berbagai Konsentrasi NaOH

Coconut pulp contains up to 18.2% protein which is one of the wastes from coconut oil processing. Protein from coconut pulp can be used in the manufacture of protein concentrates which are widely used in the food industry. The purpose of this research is to determine the concentration of NaOH that can produce the yield and protein content of coconut pulp protein concentrate. Coconut pulp protein was extracted with NaOH at various concentrations of 0.5, 1, 1.5, 2, and 2.5 M, then continued with salting out using salt (NH4)2SO4 with a saturation of 65%. The crude protein content of coconut pulp protein concentrate was determined by the Kjeldahl method. The results showed that the use of 0.5 M NaOH resulted in the highest protein content of coconut pulp protein concentrate, which was 71.30% with a yield of 14.42%.

Evaluation of salt content and effectiveness of excessive salt reduction methods in selected commercially available dried fish types in Sri Lanka

High salt intake elevates the risk of non-communicable diseases such as high blood pressure, cardiovascular diseases and stroke worldwide. Sri Lanka has recorded in 2010 as the country with highest average fish & fish products consumption in South Asia. In the current study, salt in ten types of commonly available dried fish namely; sprats, prawns, smoothbelly sardinella, queen fish, cat fish, sail fish, shark, skipjack tuna, Bombay duck and trenched sardinella was analyzed and determined salt reduction methods with minimal protein loss. Four salt reduction methods were tested; Method 1: washed with water at Room Temperature (RT) for five times; Method 2: washed with water for five times at RT and kept in hot water for 5min; Method 3: washed with water for five times at RT and boiled for 5min; Method 4: washed with water for five times at RT and kept in coconut water for 5min. Using Volhard method, sodium chloride was analyzed while protein was determined using Kjeldahl method. All four methods showed significant reduction of salt level in tested dried fish (p < 0.05). Among the tested salt reduction methods, Method 3 showed the highest salt reduction for all types of dried fish except smoothbelly sardinella and cat fish.The highest salt mean value of 28.8% was recorded in queen fish and the lowest mean value of 12.8% was recorded in smoothbelly sardinella. The highest protein loss was recorded in Method 3. To reduce considerable amount of salt, the easiest and fairly effective method is method 1 except for prawns and Shark. Although higher salt reduction showed in method 2 and 3, they are not recommended due to high protein loss, high energy expenditure and reduction of freshness of dried fish. Method 4 can be applied for all dried fish types because it is economical and reduces considerable amount of salt, removes less amount of protein comparatively. The results revealed that all tested dried fish except smoothbelly sardinella contain significantly high amount of salt (p < 0.05) than the standard value specified (12%) by the Sri Lanka Standards Institution (SLSI).Keywords: Dried fish, protein loss, salt-intake, salt reduction, non-communicable diseases

Proximate Analysis of Merang Mushrooms (Volvariella volvacea) Cultivated on Corncob and Rice Bran Media

Merang Mushroom (Volvariella volvaceae) is one of the edible mushrooms. The nutritional content of merang mushrooms makes this mushroom has potential as a medicine and food supplement. Merang mushrooms are known to function as antioxidants, antidiabetic, antiviral, and can lower cholesterol. The purpose of the research is to find out the nutritional content of merang mushrooms that are cultivated in corncob media with the addition of rice bran. The analysis used was proximate analysis to determine moisture, ash, and fiber content using the AOAC method, fat content analysis using the Soxhlet method, protein content analysis using the Kjeldahl method, and carbohydrate Analysis (By difference). The results of the analysis were 2.17% ash content, 85.14% water content, 3.65% crude fiber content, 1.99% fat content, 2.7% crude protein content, and 8.0% carbohydrate content. Based on research, it can be said that mushroom has a good nutritional content that can provide health benefits.

Influence of different concentrations of ammonium phosphate on nitrogen assimilation of red seaweed Kappaphycus striatus

Eucheumatoid farming is among the most popular source of livelihood for coastal dwellers, especially in the southern Philippines. Kappaphycus and Eucheuma are the two major cultured eucheumatoid species. However, seaweed farmers have been experiencing low seaweed production for the past years. The slow growth of Kappaphycus spp. in the farm is linked to extensive farming, causing nutrient depletion in the seawater. Hence, seaweed farmers in the province of Tawi-Tawi, southern Philippines, enrich their seaweeds, Kappaphycus striatus, with a wide range of inorganic nutrient solution concentrations with an average of nearly 9 g L⁻¹. To provide standard concentration (g L⁻¹) of inorganic nutrient solution for soaking before farming the seaweed, this study investigated nitrogen assimilation using the Kjeldahl method. Treatments were the concentrations of commonly used inorganic fertilizer [ammonium phosphate, (NH4)3PO4] dissolved in filtered seawater namely; T1 = 0 g L⁻¹ as control, T2 = 3 g L⁻¹, T3 = 6 g L⁻¹, and T4 = 9 g L⁻¹. Results showed that the total nitrogen (%) of T4 (0.68±0.01) and T3 (0.59±0.07) were significantly higher (p<0.05) than T2 (0.48±0.02) and T1 (0.46±0.02). This suggests that using inorganic nutrients as enrichment to K. striatus at a concentration of 6 or 9 g L⁻¹ is effective for obtaining high nitrogen assimilation. Therefore, considering the cost-effective inorganic nutrient enrichment practice, this study recommends using 6 g L⁻¹ of inorganic nutrient concentration to help seaweed farmers boost production by improving the growth performance of K. striatus, especially when planted in nutrient-depleted farms.

The content of basic elements in buckwheat flour as affected by varietal characteristics

- Purpose. Determine the biochemical composition of buckwheat as affected by varietal characteristics. Methods. Humidity was determined by thermogravimetric method, protein content by the Kjeldahl method, carbohydrate content by sugar meter, ash content by burning in a muffle furnace, fat content by low-fat residue, vitamin content by liquid chromatography. Results. The biochemical composition of buckwheat grain varied significantly depending on the variety. Studies have shown that at a moisture content of 11.0–12.6%, the content of fiber, organic acids, ash, mono- and disaccharides and fat was the lowest. Thus, their content over varieties was 0.5–2.5%, 1.7–2.4, 1.5–2.5, 1.6–2.5 and 2.0–3.2%, respectively. Of the 17 varieties of buckwheat, only 4 had a significantly lower protein content (13.2–14.0%) compared to the standard variety ‘Ukrainka’. In other varieties, this figure varied from 16.3 to 18.5% or more, that is by 9–23% compared to the control. Buckwheat had the highest starch content of 57.2–62.0% depending on the variety. It should be noted that no significant difference was found between tall and dwarf varieties. Thus, the protein content in grain obtained from dwarf varieties varied from 16.5 to 17.2% while in tall ones from 13.2 to 18.5%. The content of vitamins in grain also varied depending on the variety from which it was obtained. The content of vitamin K was the lowest, 0.005–0.007 mg/100 g, the content of vitamins B2, B1, B5 and B6 varied from 0.12 to 0.42 mg/100 g of grain. The content of vitamin E and B3 was higher, 3.00–6.56 mg/100 g of grain, depending on the variety. The highest content of B4 was 50.0–54.3 mg/100 g of grain. It should be noted that the share of vitamin K in the total amount was the lowest (0.01%), the share of vitamins B2, B1, B5 and B6 ranged between 0.2 and 0.7%, E and B3 between 6.1 and 10.3%, and vitamin B4 between 80.3 and 85.9%. According to the content of vitamins, the difference between buckwheat varieties has not been found. The level of vitamins provides a determination of the integral rate of the product. It was found that 100 g of buckwheat provides the adult body with vitamin K by 4–7%, B5 – by 6–9, B4 – by 10–11, B2 – by 11–24, B1 – by 11–36, B6 – by 12–23, E – by 27–44, B3 – by 21–44% depending on the variety. Conclusions. As a result of research, it was found that the biochemical composition of grain varies significantly depending on the buckwheat variety. Buckwheat contains the most vitamins E (3.00–6.63 mg/100 g of cereal) and B4 (51.0–54.3 mg/100 g of cereal). It is determined that grain obtained from ‘Orlovskyi’, ‘Podilskyi’, ‘Yana’, ‘Sumchanka’, ‘Anisia’, ‘Krupnozelena’, ‘Skorostyhla 81’ and ‘Kvitnyk’ varieties have a high content of vitamins B2, B1, B6, E and B3 with an integrated rate of 16–44%. In addition, grain of these varieties contains 16.5–17.4% of protein.

Black Soldier Fly Larvae (Hermetia illucens) as a Waste Reduction Agent and an Alternative Livestock Feed

Black Soldier Fly or Hermetia illucens is an insect that is currently being studied for its characteristics and nutrient content. Black Soldier Fly comes from America which spreads to subtropical and tropical regions. BSF larvae could be develop, grow, in a various organic waste media, because their high tolerance in a pH fluctuation. Some of factors that determine the success of animal feed are the quality and nutrient content itself. The livestock industry is the largest component in the business of providing animal feed reach of 50-70%. The important component in animal feed is protein. Protein content plays an important role in body metabolism, tissue formation, and growth rate. This research aimed to detect nutrient content of BSF larvae with use of various organic waste as their growth media. Analysis of nutrient content (proximate) in larvae includes protein (Kjeldahl method), lipid (Soxhlet method), carbohydrate, and water content. The proximate analysis obtained showed the differences in each type of waste media with the average values of protein, carbohydrates, and fats, respectively, 42.63%, 21.47%, 21.38%. Protein content is the highest element in BSF larvae in all types of growing media.

Bromatological characterization of fruit waste

In Colombia, a high amount of fruit waste is currently generated. These causes a negative environmental impact due to its high organic load. However, this type of waste has compounds in its structure that can be used in order to reduce the environmental impact and to obtain added value. The main of this study was to characterize bromatologically sixteen residues of fruit processing in Colombia, in order to propose a possible use in the food industry. The bromatological characterization of the waste was carried out by means of the quantification of dry matter (ASTM E1756-08), ash (ASTM E1755-01), proteins (Kjeldahl method), crude fats (AOAC Official Method), total dietary fiber (AOAC 993.21) and carbohydrates. It was found that grape and soursop seeds, lulo peel and tree tomato stem presents the highest total dietary fiber with content percentages above 50 %. Also, tree tomato, soursop, tangerine and orange seeds are an important source of protein and crude fats, with values highest than 12 and 27 %, respectively. It was also found that pineapple, mango, soursop and grape peel have a carbohydrate content greater than 50%. As a conclusion, the results of this study demonstrate that fruit waste have a potential use in the food industry, due to their protein, crude fat, total dietary fiber and carbohydrates content.

Physicochemical Parameters of Yak Meat during Massaging and Salt Pickling.

Yak meat can facilitate the development of new branches of animal husbandry and the meat industry. To improve the functional and technological properties of raw meat materials and improve the quality of premade products, a promising direction is the creation of new technological solutions based on the targeted use of natural food additives in the process of salt pickling. To study the physicochemical parameters of yak meat (longissimus dorsi muscles) in the process of salt pickling and continuous massaging in a cyclic mode. The pH, moisture, fat, protein, and sodium chloride content was taken as the basis for the study of physicochemical parameters. To determine the effect of massage, various methods were implemented, such as analysis, observation, accelerated method, etc. The protein content was determined by the Kjeldahl method on a Kjel-Foss-16200 device. The study found that in fibers containing a large amount of glycine, the salting takes place faster. This process occurs due to the high permeability of the membranes. It has been determined that the longer the muscles, the faster the distribution process is. It was found that when massaging for up to 60 min, an increase in muscle fibers occurs along with the homogenisation of the protein mass. If the process is continued for up to 120 min, then the membrane begins to collapse in the meat, and the sarcolemma ruptures. Based on the study, it was found that the most optimal massaging time is 90 min, which helps to reduce the production cycle. Yak meat can facilitate the development of new branches of the meat industry. Highly efficient meat processing technologies are the main factor contributing to the increase in the competitiveness of meat products. The use of protein-vegetable compositions in brines makes it possible to improve organoleptic characteristics.

An integrated laboratory experiment for the determination of main components in different food samples.

An integrated laboratory experiment was designed for introducing biochemistry students to basic static biochemistry to deepen their understanding on the properties and analysis of biomolecules such as total carbohydrates, lipid, protein, and protein-constituent amino acids. Food represents a very important source of biomolecules of technological and functional interest; therefore, 15 types of food samples were selected to demonstrate the analysis of basic composition of these biomolecules. In this experiment, students learnt testing the total carbohydrates of all the food samples using 3,5-dinitrosalicylic acid (DNS) method, while performing acid hydrolysis. Then, lipid extraction was done using Soxhlet extraction method in order to determine the crude lipid concentration in different samples. After this, the students learnt testing crude protein content of these samples by using Kjeldahl method, and amino acid analysis was performed using HPLC. From the experiments, students grasped the concept and advantages of these methods and deepened their understanding on compositional analysis of different food samples. This laboratory exercise can be included into any college-level biochemistry courses and gives hands-on experience to the students for conducting scientific research in the field of life sciences, food science, and other bio-related fields.

One-Dimensional Convolutional Neural Networks for Hyperspectral Analysis of Nitrogen in Plant Leaves

Accurately determining the nutritional status of plants can prevent many diseases caused by fertilizer disorders. Leaf analysis is one of the most used methods for this purpose. However, in order to get a more accurate result, disorders must be identified before symptoms appear. Therefore, this study aims to identify leaves with excessive nitrogen using one-dimensional convolutional neural networks (1D-CNN) on a dataset of spectral data using the Keras library. Seeds of cucumber were planted in several pots and, after growing the plants, they were divided into different classes of control (without excess nitrogen), N30% (excess application of nitrogen fertilizer by 30%), N60% (60% overdose), and N90% (90% overdose). Hyperspectral data of the samples in the 400–1100 nm range were captured using a hyperspectral camera. The actual amount of nitrogen for each leaf was measured using the Kjeldahl method. Since there were statistically significant differences between the classes, an individual prediction model was designed for each class based on the 1D-CNN algorithm. The main innovation of the present research resides in the application of separate prediction models for each class, and the design of the proposed 1D-CNN regression model. The results showed that the coefficient of determination and the mean squared error for the classes N30%, N60% and N90% were 0.962, 0.0005; 0.968, 0.0003; and 0.967, 0.0007, respectively. Therefore, the proposed method can be effectively used to detect over-application of nitrogen fertilizers in plants.

The balance of nitrogen forms and number of microorganisms of the nitrogen cycle in vermicomposts based on leaf litter and cow manure

The processes of nitrogen transformation in the vermiculture system by Eisenia fetida using cow manure and leaf litter (poplar with small birch addition) have been investigated. Vermicomposting was carried out for five months in half-cubic meter wooden containers. The Kjeldahl method and potentiometry determined the total nitrogen, NH4 + and NO3- content in vermicompost. The total nitrogen content in cow manure was 1.83%, in leaf litter - 0.73%. The nitrate and ammonium content in non-composted leaf litter was 351 and 7.3 mEq/kg of dry matter, respectively. The nitrate and ammonium content in non-composted cow manure was 18.2 and 22 mEq/kg, respectively. Both investigated substrates of vermicomposting did not influence total nitrogen content. In cow manure-based vermicomposting system, the ammonium amount decreased by 5.3 times, while the concentration of nitrates increased by 6.5 times. In the leaf litter-based vermicomposting system, the ammonium amount increased by 2.9 times, and the amount of the nitrate increased by 1.6 times. The Azotobacter bacteria actual activity in both vermicomposts was close to 100%. The sum of nitrogen cycle microorganisms in manure vermicompost was 2.4 times higher than in leaf litter vermicompost.

Feed Parameters Influencing the Breeding of Mealworms (Tenebrio molitor)

With the growing public interest in edible insects, breeders are forced to increase the volume of production and shorten the life cycle of farmed insects. The exact composition of the feed is the know-how of each manufacturer. The aim of this work was to determine the general impact of individual conventional types of feed (bran, whey, raw ware potatoes) on the life cycle rate of Tenebrio molitor (TM), larval mortality and the content of fats, fatty acids and nitrogenous substances in larvae and their excrements. For the reasons of sustainability of the state of nature and waste disposal, polystyrene foam was added to the experiment as feed. The experiment was performed in two phases—rearing for 21 weeks and 5 weeks. The nitrogen content was determined using the Kjeldahl method (ISO 1871: 2009), the fat content by the Soxhlet method and the fatty acid profile using a gas chromatograph with a flame ionization detector (FID). The results of the work show that the basis of the TM feed is wheat bran, not only due to the observed low larval mortality (45% over 21 weeks) and their optimal nutritional value (nitrogenous substances 53.6% DM, fat 37.1% DM, the highest total fatty acid content) but also due to the higher speed of TM development. Lower larval mortality during rearing was found when feeding dried whey and raw ware potatoes, but the development cycle rate was low. This confirmed that the bran as a feed allowed a fast life cycle with good larval nutritional parameters. From a nutritional and reproductive point of view, TM appeared to be a suitable alternative to animal production. Polystyrene as a feed, tested for biodegradation by TM larvae, caused the highest larval mortality (75% in 21 weeks). However, the content of nitrogenous substances in the larvae increased to 69.77%, in the excrement, it even increased to 82.68%, and there was no cannibalism among the larvae. The work thus demonstrated the possibility of biodegradation of polystyrene using TM larvae with an increase in nitrogenous substances in both larvae and excrement.

Bazı lokal selülozik atıklar üzerinde kültürü yapılan Pleurotus ostreatus (Jacq.) P. Kumm.’un besin içeriği

In this study, the effects of different cellulosic wastes on the nutritional values of Pleurotus ostreatus (Jacq.) P. Kumm. were investigated. Dry matter, moisture, protein, fat and ash contents of P. ostreatus were analyzed according to AOAC methods. Crude protein and fat contents were determined by the Kjeldahl method and Soxhlet extraction, using ether as a solvent, respectively. Chemical composition of P. ostreatus such as dry matter, moisture, crude protein, fat and organic matter were 93.5-93.7%, 6.3-6.5%, 25.2-33.5%, 1.7-2.5%, 5.3-9.7% and 84.0-88.2% of dry weight, respectvely. There were no significant differences in dry matter and moisture content of P. ostreatus grown on various local residues (p&gt;0.05), but changeable in other nutrient composition (p

Portuguese Kelps: Feedstock Assessment for the Food Industry

Seaweeds have been incorporated in the daily diet of several human cultures since ancient times, due to their nutritional characteristics and healthy properties. The brown seaweeds Undaria pinnatifida, Saccharina latissima, Sacchoriza polyschides, and Laminaria ochroleuca were collected in the Viana do Castelo (Portugal) bay to assess their proximate composition analysis. As a result, the algal biomass was dried, and its moisture and ash content were determined. The dried biomass was then analyzed for total nitrogen/total protein (using the Kjeldahl method), total fiber content (through fiber analyzer digestion), total lipids (in a Soxhlet apparatus), and fatty acid characterization (by gas chromatography-mass spectrometry). Apart from phosphorus, which was analyzed by spectrophotometry, the ashes were employed for mineral and trace element characterization via dry mineralization and quantified using flame atomic absorption spectrometry. Moreover, the total phenolic content was assessed spectrophotometrically by the Folin-Ciocalteu method in the algal aqueous extracts. Analyses showed that their protein concentrations ranged from 12 to 24% dry weight (DW), while lipid concentrations varied between 0.51% and 1.52% DW. Regarding the carbohydrate concentration in these seaweeds, a concentration between 48% and 60% DW was observed. The S. polyschides had the highest overall total phenolic content (6.19 × 10−3 g GAE/100 g of dried algae), while L. ochroleuca had the lowest amount (3.72 × 10−3 g GAE/100 g of dried algae). U. pinnatifida had the highest total fatty acid content (35.13 mg/g DW), whereas S. latissima presented the lowest value (22.59 mg/g DW). Significant concentrations of highly unsaturated fatty acids (HUFA) were observed in both seaweeds, with U. pinnatifida having the highest value (10.20 mg/g DW) and S. latissima the lowest content (4.81 mg/g DW). It is also highlighted that these seaweeds have a nutritional relevance as a source of essential nutrients, including nitrogen, potassium, sodium, calcium, magnesium, and iron.

Coagulation of turbid wastewater with an active component extracted from Moringa oleifera seeds

ABSTRACT The oil and carbohydrates contained in the Moringa oleifera seeds (MO) are two parameters that inhibit its coagulant potential. Oil extraction and protein purification are therefore necessary to improve its performance. The extraction process to recover the maximum oil yield was carried out using the solvent chloroform: ethanol C: E in a ratio (3:1). At a temperature of 100°C, the yield was higher than 44%. Purification was carried out by salting-in the protein with 1 M NaCl combined with ethanol precipitation and heat treatment. Analysis of the protein powder by the Kjeldahl method revealed 92% pure protein and 14% nitrogen; energy dispersive X-ray (EDX) analysis revealed high percentages of carbon (45%) and oxygen (39%). Scanning electron microscopy (SEM) showed a porous surface, and X-ray diffraction identified a crystalline phase of protein. The isoelectric point of Moringa oleifera protein (MOP) is in the range of pH 6.5–7.5 and its zeta potential varies between −19 mv and + 25.49 mV. It indicates a lower level of dispersion stability, implying a high capacity for protein agglomeration and flocculation. By reducing the zeta potential of water from −16 mv to −1.18 mv after treatment without modifying its pH, the Moringa protein has proven its ability to destabilise organic colloids. Moringa protein as a coagulat aid is effective for high turbidity wastewater with removal up to 86.78% and DOC removal up to 56.52%. The study reveals that coagulation with Moringa protein is a cost-effective alternative since it reduces the quantity of coagulant and time required for wastewater treatment.

The effect of planting season on physical and chemical characteristics of local rice varieties

The season is the time interval with the most frequent weather. The rainy season is the time when it rains a lot, while the dry season is the time when it rains a little. Planting season is one of the factors that affect the quality of the grain, which directly determines the quality of rice. This study aims to determine the effect of the growing season on the physical-chemical characteristics of rice. The sample observed was the Bujang Marantau rice (local variety) which was taken from two seasons (dry season and rainy season) in the same location, which is Nagari Singkarak, X Koto Singkarak District, Solok Regency, West Sumatra Province. The physical characteristics examined were head rice, broken rice, and groats. Chemical characteristics analyzed were amylose content determined by the IRRI method (1971). Meanwhile, water content and ash content were analyzed by the gravimetric method. In addition, fat content was determined by the Soxhlet method with Weibull modification. Furthermore, protein content was determined by the Kjeldahl method. The results showed that the growing season did not affect the ash content, fat content, and carbohydrates of the Bujang Marantau rice, but affected the water, protein, and amylose content. Based on the quality requirements (SNI 6128:2015), Bujang Marantau rice is included in the medium quality class 1.

Environmental assessment of soil quality indices using near infrared reflectance spectroscopy

The main purpose of this preset study is to assess soil quality indices in form of potassium (K) and phosphorus (P) contents using a non-invasive and environmental friendly approach namely near infrared reflectance spectroscopy. Soil samples were obtained from Aceh Besar district in rice field land-use. Near infrared spectral data of soil samples were acquired and recorded as absorbance in wavelength range from 1000 to 2500 nm. On the other hand, actual P and K were measured using standard laboratory procedures by means of Kjeldahl methods. Spectral data were corrected and pre-treated using mean centering approach and applied to all dataset. Prediction models were developed using principal component regression and validated using leverage cross validation. The results showed that both soil quality indices can be predicted with maximum correlation coefficient (r) of 0.98 and ratio prediction to deviation (RPD) index of 3.47 for P, and r of 0.91, RPD of 2.68 for K respectively. It may conclude that environmental assessment, particularly for soil quality determination can be conducted rapidly and non-invasively using near infrared spectroscopy approach.