Indonesian Journal of Agricultural Research

Evaluating the Shelf Life of Chilled Raw and Pasteurized Goat Milk: An Analysis of Physicochemical and Microbial Content

N. S. Ibrahim — 2024-02-26

Goat milk offers a variety of health benefits. The objective of this study is to evaluate the influence of refrigerated storage on the quality of unprocessed and pasteurized goat milk within a defined timeframe. In addition, also analyzes the chemical and microbiological composition of both raw and pasteurized goat milk during refrigerated storage to assess its longevity. Goat milk samples were obtained from healthy Saanen female goats, aged 3-4 years, with a body condition score (BCS) ranging from 2 to 3. The samples were taken from UniSZA Pasir Akar farm in Besut, Terengganu, Malaysia. The milk samples were processed through pasteurization. Exactly 10 goats were meticulously chosen, with each goat yielding 1 liter of milk. The goats were segregated into two cohorts: one cohort for raw milk (n=5) and the other for pasteurized milk (n=5). Subsequently, the milk samples from both groups were subjected to chilling storage experimentation at the food technology laboratory of Universiti Sultan Zainal Abidin (UniSZA) in Besut. The milk samples (duplicates) were monitored for 42 days to assess their physical characteristics. The pasteurized goat milk samples were evaluated for milk composition (fat, solid non-fat, protein, and lactose) and microbial contents (TPC and EMB) from Week 0 to Week 6. The effect of shelf life, composition values, and bacterial growth were measured weekly, and the data were presented descriptively (SEM±STD) with paired T-Test as the statistical analysis, considering p<0.15 as a significant difference. The findings revealed a downward trajectory in the physical attributes and chemical makeup of both unprocessed and pasteurized goat milk throughout the storage duration, resulting in decreases in fat, solid non-fat, protein, and lactose. The microbiological investigation revealed increased microbial levels in both raw and pasteurized milk after two weeks. Nevertheless, there was a subsequent decrease in the number of microorganisms from week 3 to week 6, indicating a phase of natural bacterial decline caused by limited nutrients and competition among bacteria. The study emphasizes the significance of maintaining sustainability in dairy production and addressing food safety concerns. It is crucial for customers to be informed about the duration of safe consumption of pasteurized milk and the potential threat of bacterial growth during prolonged cold storage

Nitrogen-Fixing Purple Nonsulfur Bacteria Originating from Acid Saline Soils of a Rice-Shrimp Farm

Nguyen Hoang Anh — 2024-03-01

The study was conducted to (i) isolate, select, and identify strains of purple nonsulfur bacteria (PNSB), which can fix nitrogen (N), from soil and water in a rice-shrimp integrated system, (ii) to determine the capacity of the selected potent PNSB strains in producing plant growth promoting substances. The isolation resulted in 57 pure PNSB strains from 36 soil samples and 36 water samples of rice-shrimp paddy fields in Thanh Phu - Ben Tre. Among them, 49 strains survived under pH 5.0 conditions, 24 of which grew well under microaerobic light (ML) and aerobic dark (AD) conditions in a basic isolation medium (BIM) containing NaCl 5‰. Two strains (S01 and S06) with the greatest N fixation were identified by 16S rRNA techniques as Rhodobacter sphaeroides. Their N production was 16.9 mg L^-1 under the ML condition and 32.1 mg L^-1 under the AD condition. Moreover, two R. sphaeroides S01 and S06 strains performed P solubilization at 0.382-2.954 mg L^-1 from Al-P, 3.81-4.28 mg L^-1 from Fe-P, and 3.87-4.74 mg L^-1 from Ca-P, and production of plant growth promoting substances, such as IAA (12.3-15.5 mg L^-1), EPS (1.09-1.58 mg L^-1), siderophores (10.7-53.6%) and ALA (1.68-2.82 mg L^-1) under both the incubating conditions.

Inhibition of Maillard Reaction of Kepok Banana Flour with Citric Acid

Anang Legowo — 2024-03-07

Bananas are a type of climateric fruit that undergoes post-harvest ripening, so bananas are easily damaged and have a short shelf life. Kepok banana flour is one of the food diversification products that can increase add value of kepok bananas. The production of kepok banana flour produces brown flour, so the appearance of flour is less attractive. Research aimed to improve quality of kepok banana flour using citric acid. The experimental design used was a Completely Randomized Design (CRD) with 5 treatments and 4 replications. The treatments given were citric acid concentrations of 0%, 0.2%, 0.4%, 0.6%, and 0.8%(w/v). The results obtained were whiteness index values of 75.07%-78.20%, water content of 3.05%-3.55%, reducing sugar of 0.03%-0.012%, color of 1.76-2.16, aroma of 2.00-2.80, and overalls of 2.68-2.92. Increase in the citric acid concentration may increase the reducing sugar, whiteness index, and water content kepok banana flour. The best treatment in the study was a concentration of 0.8% among others.

The Effect of the Amount of Stevia Leaf Powder (Stevia rebaudiana) and Drying Time on the Quality of Snake Fruit Padang Sidempuan Dried Candied

Riska Putri Armaya — 2024-03-10

This study aimed to determine the Effect of using stevia leaves as a natural sweetener on dried sweets of Padang Sidempuan's snake fruit. The method used in this study was the factorial Complete Randomized Design (CRD) method with two factors, namely the amount of stevia leaf powder (0,20%: 0,25%; 0,30%; 0,35%) and drying time (4, 6, 8 and 10 hours). The tests carried out were moisture content, ash content, total sugar, total dissolved solids, total microbes, acidity (pH), and organoleptic tests of colour, flavour, taste, and texture. This study's results showed a highly significant effect exerted by the amount of stevia leaf powder on moisture content, ash content, total dissolved solids, total sugar, total microbes, acidity (pH), and an organoleptic test of colour, flavour, and taste. Drying time significantly affected moisture content, ash content, total sugar, total microbes, total dissolved solids, and texture organoleptic test. The interaction between the amount of stevia leaf powder and the drying time had a highly significant effect on moisture content and a significantly different effect on total microbes and organoleptic colour. The amount of stevia leaf powder is 0,35%, and the drying time of 8 hours results in the best treatment on dried sweets of Padang Sidempuan's snake fruit.

Comparison of Carcass Percentage Among Four Duck Breeds under Traditional Rearing Conditions

Harapin Hafid — 2024-03-12

The research aims to determine the extent of differences in the carcass composition of four types of ducks using semi-intensive cultivation. A total of 16 ducks aged 3 months were used as experimental units. A completely randomized design with 4 treatments and 4 replications was the research design. The results showed that ducks of the same age, namely: Alabio ducks, Peking ducks, Mojosari ducks, and Manila ducks, showed very significant differences (P<0.01) in the variables of slaughter weight, carcass percentage, thigh and back percentage. However, there was no significant difference (P>0.05) in the percentage of chest, wings, and neck. It was concluded that the live weight, carcass percentage, and carcass parts of Manila ducks were higher than those of Alabio, Peking, and Mojosari ducks. Meanwhile, Alabio ducks are taller than Peking ducks and Mojosari ducks.

Assessment of the Farmer Field Schools Activities as Strategy to Enhance Capacity Building of Smallholder Rural Cocoa Farmers in Kwara State, Nigeria

K. Fatai — 2024-03-18

The study assessed the Farmer Field Schools (FFS) activities as a strategy to enhance capacity building of rural smallholder cocoa farmers in Kwara State, Nigeria. A descriptive survey to enhance the capacity to conduct the research. A purposive sampling procedure was used to select 160 smallholder rural cocoa farmers who participated in the FFS activities in Kwara State. A structured interview schedule was used to collect the data from the respondents. Data were gathered on the socio-economic characteristics of smallholder cocoa farmers and the skills provided by FFS to smallholder cocoa farmers. Data was analyzed using mean, frequency counts, percentages, and chi-square at 0.05 level of significance. The result revealed that 91.3% were male, while 8.7% were female. The result showed that all the skills needed were provided by FFS. The results showed that FFS activities had a significant relationship with the FFS skills provided and the training needs of the rural smallholder cocoa farmers with a p-value of 0.001 being < 0.05. The findings concluded that farmer field school activities had a positive relationship between the skills provided and the training needs of cocoa farmers and this is because the skills provided by FFS are in line with the training needs of cocoa farmers. The study recommends that the Kwara State Ministry of Agriculture through the FFS should continue to serve as a training base that involves more farmers in the program and encourage extension service delivery to encourage capacity building and increase productivity.

Correlation of Antioxidant Properties Between Immature and Mature Okra (Abelmoschus Esculentus) Fruits

Miza Badriah Nazri — 2024-03-18

This study aimed to assess and compare the antioxidant activity and content (total flavonoid levels and total phenolic) of mature and immature okra. The antioxidant activity of okra fruits was assayed using four methods, namely: Aluminium Chloride Colorimetric assay, Folin-Ciocalteu assay, 1, 1-diphenyl-2-picrylhydrazyl (DPPH), and Reducing Antioxidant Power assay (FRAP) assays. The immature, mature, and very mature okra samples (less than 8 days, 10-15 days, and more than 20 days, respectively) were extracted using two different solvents (65% ethanol and water). The sample that was extracted with mature ethanol had the highest Total Phenolic Content (TPC) at 21.564 ± 1.635 mg GAE/g, while the sample that was extracted with extremely mature ethanol had the highest TFC at 54.391 ± 8.224 mg QE/g. The mature 65% ethanolic extracted sample showed the lowest IC₅₀ value of DPPH scavenging activity (0.920± 0.096 mg/ml), and the mature ethanol extracted sample had the highest FRAP value (232.018± 5.337 μmol Fe2+/g). These studies showed that ethanolic extracts of mature Abelmoschus esculentus had higher antioxidant content and activity than okra water extracts. Based on the DPPH Radical Scavenging Assay revealed favourable associations between TPC (r = 0.860), TFC (r = 0.742), and antioxidant activity as evaluated by FRAP, demonstrating that both phenolics and flavonoids contributed to the extract’s antioxidant properties. Both TPC and TFC showed negative correlations with IC₅₀ values (r = -0.766, r = -0.650, respectively). In conclusion, the mature okra fruits extracted with 65% ethanol give higher antioxidant content than the water extracts of okra fruits and potentially be used as a source of antioxidants rather than be discarded.