Journal of Agricultural, Food and Environmental Sciences, JAFES

THE EFFECT OF STARTER CULTURES ON WEIGHT LOSS IN DRY-CURED PORK LOIN PRODUCED WITH AND WITHOUT NITRITES

2023-10-19T19:16:01+02:00

Since ancient times, man has used caves and natural shelters as an ideal places for drying meat. Dry cured meat products are products of high nutritional value and a long shelf life. Therefore, they occupy a special place on the consumers' tables. This research aims to determine how added starter cultures affect on weight loss during the production process in dry-cured pork loin produced with and without nitrites. Five groups of dry-cured pork loin were produced in three iterations. I (the first) negative control group (table salt, dextrose), II positive control group (nitrite salt, dextrose); Group III (nitrite salt, dextrose and starter culture), group IV (table salt, Swiss chard powder from the first manufacturer, dextrose and starter cultures) and group V (table salt, Swiss chard powder from the second manufacturer, dextrose and starter cultures). The weight loss during salting ranged from 2.37 (II group) to 2.50 (III group). After smoking, the weight loss ranged from 10.84% (II group) to 11.27% (V group). During ripening, the weight loss ranged from 30.99 (I group) to 31.61 % (III group). The weight loss during the entire production process was the highest in group III (40.83%), while it was the lowest in group I (40.10%). The difference in weight loss observed between groups was statistically significant (p ≤ 0.05). Added starter culture in dry-cured pork loin contributes to a higher weight loss during the production process, which contributes to shortening the production process and more profitable production.

SUSTAINABLE CULTIVATION PRACTICES FOR MITIGATION OF CLIMATE CHANGE ON PEPPER (Capsicum annuum L.) CROP

2023-10-25T14:01:51+02:00

This study investigates the potential of integrating sustainable agricultural practices to mitigate climate change impacts on the cultivation of pepper (Capsicum annuum L.) in the arid regions. Climate-induced challenges such as desertification have further aggravated the issue of pepper cultivation. The experiment was executed in Kochani region in 2021, employing a randomized block design with five different fertilizer treatments including a notable biofertilizer, Trichoderma harzianum. The agronomic parameters such as fruit length, diameter, mass, pericarp thickness, and yield have been analysed. The mixed fertilization treatment (MIX) illustrated a significant enhancement in fruit dimensions and yield, whereas the Trichoderma treatment (TRICH) exhibited a notable reduction in non-marketable fruits. The findings validate that the incorporation of Trichoderma with organic and mineral fertilizers not only bolsters plant growth and yield, but also strengthens climate resilience in pepper cultivation. This increases the understanding of biofertilizer utilization in sustainable agriculture, especially in regions struggling with climate adversities. Furthermore, the study underpins the necessity for advanced knowledge in leveraging live organisms like Trichoderma for increasing agricultural productivity and climate resilience in arid regions.

PHENOTYPIC DIVERSITY OF LOCAL PEPPER (Capsicum annuum L.) VARIETIES INTENDED FOR DEHYDRATION

2023-10-25T14:08:20+02:00

Peppers are one of the most divergent group of vegetables globally. In part of the Balkan region, but mostly in Macedonia there are distinct local varieties, intended for drying as a whole fruit on strings and are used in traditional dishes, processed foods and as condiments. A collection of 21 local pepper (Capsicum annuum L.) varieties intended for drying in traditional manner, was evaluated for 26 plant traits. The Principal Component Analysis yielded 5 principal components with eigenvalue > 1, explaining 81.48 % of the variability. The first two principal components were highly corelated with 8 plant traits (FL – fruit length, FWg – fruit weight (g), PL – pedicel length (cm), PT – pericarp thickness (mm), PW – plant width (cm), LL – leaf length (cm), DFL-days to flowering, DFR – days to fruiting). The cluster analysis, based on those traits was performed and resulted in grouping the accession into three clusters. The first included accessions with highest values for the analysed traits, while the third cluster included accessions with lowest values for days to fruiting and maturity. The initial characterization of the investigated pepper germplasm, based on qualitative and quantitative plant traits, revealed high variability among the accessions.

BACILLUS SPP. – A POTENT BIOLOGICAL CONTROL AGENTS AGAINST DOWNY MILDEW OF GRAPEVINE

2024-02-20T10:18:51+01:00

Plasmopara viticola, the causal agent of downy mildew of grapevine, is one of the most devastating and economically most important grapevine pathogens worldwide. In the Republic of North Macedonia, control of downy mildew in grapevine is mainly achieved by application of synthetic fungicides. However, the long-term and continuous use of synthetic fungicides leads to appearance of resistant strains of the pathogen, residues and environmental pollution. Alternatives to chemical control such as the use of biological control agents or resistant cultivars, currently play a small role in controlling this disease. A promising alternative strategy that could replace or be combined with fungicides are biofungicides. The main goal of the experiment was to observe the possibility for biological control of grape downy mildew by the use of two novel biofungicides, Sonata (a.m. Bacillus pumilus QST 2808) and Serenade Aso (a.m. Bacillus subtilis QST 713). Experiment was conducted during the 2019 in two vineyard regions in the Republic of North Macedonia (Demir Kapija and Negotino), on three grape varieties (Merlot, Riesling and Vranec). Both tested biofungicides showed almost equal efficacy, with more than 94% reduction of disease severity index on leaves in Vranec and Riesling varieties and with more than 97% reduction of disease severity index on leaves in Merlot variety. On bunches, both biofungicides achieved 100% reduction of disease incidence and severity index in all three varieties. The results showed that Bacillus pumilus and Bacillus subtilis are potent biological agents and have a prospective use for control of downy mildew in grapevine.

DETERMINATION OF CD, PB, AS, ZN, CU IN VEGETABLES AND VEGETABLE PRODUCTS AND HERBS

2023-12-21T12:45:16+01:00

In order to control the hygienic and health conformity of vegetable food products from the consumer basket for the preparation of a full-day military meal, among other analyses, the maximum allowable quantities of the elements Cd, Pb, As, Zn, Cu are monitored. With the AAS technique, three samples each of twenty fresh vegetables, vegetable products and herbs were analyzed and the quantity of the elements of interest was examined. The results of the examination of three samples of: fresh beans, carrots, potatoes, onions, cabbage, spinach; canned vegetables: peas, green beans, peppers (glass and tin packaging), beets (glass and tin packaging), cucumbers (glass and tin packaging), tomato paste, mushrooms; herbs: ground paprika, black pepper, parsley and mixed seasoning are presented. The samples are from different producers from the Macedonian area. Using the method of comparative analysis, it was concluded that the obtained results are in accordance with the norms of the rulebook and those of the literature.

ON CV-AAS DETERMINATION AND SPECIATION OF MERCURY IN WINE

2024-01-14T18:17:27+01:00

The possibilities of cold vapor - atomic absorption spectrometry (CV-AAS) for the determination and speciation of mercury in wine samples are critically discussed in the present study. In the first step, the direct determination of Hg using SnCl₂and NaBH₄ as reducing agents is attempted. The influence of the type of reducing agent and its concentration, as well as the concentration of HCl on the absorbance signal of the different Hg species (Hg²⁺ and CH₃Hg¹⁺) is investigated. The results show that direct determination of both Hg species is possible: inorganic Hg can be selectively determined by using 0.04% NaBH₄and 1 mol/l HCl directly in an untreated wine sample; both Hg species are determined simultaneously by using 0.9% NaBH₄and 1 mol/l HCl again directly in an untreated wine sample. The recoveries obtained by using HCl at a concentration below 1 mol/l are lower than 85% which can be considered as evidence that the mercury in the wine sample is bound in some complex compounds. In the second step, a separation and preconcentration method for Hg determination in wine is proposed. Two sorbents were compared for the separation and preconcentration of Hg: Chelex 100 and Dowex 50W. The quantitative sorption of both Hg species was achieved by using Chelex 100 at pH 4. Quantitative elution of the Hg retained on the resin is possible with 2 mol/l HNO₃. The influence of interfering factors Fe and Cu on the absorption signal is investigated, and the optimal wine amount and dilution are suggested. The limits of determination of the analytical procedure consist of Hg pre-concentration on Chelex 100 followed by CV-AAS measurement of eluted Hg, which allows the determination of total Hg in all types of wine samples with their natural contents.

QSAR MODELING OF pKа VALUES OF SULFONYLUREA HERBICIDES

2024-01-14T18:35:48+01:00

Sulfonylureas are herbicides primarily used for control of weeds in early growth stages of cultivations. Structurally sulfonylureas contain a sulfonyl group with sulphur atom bonded to nitrogen atom of an ureylene group. According side chains there are pyrimidinyl-sulfonylureas and the triazinyl-sulfonylureas. Swiss ADME descriptors have been used to develop QSAR models for predicting the pKa values of selected 27 sulfonlyurea herbicides: 17 pyrimidinyl- and 10 triazinyl-sulfonylurea herbicides. Variable selection methods including stepwise, forward, and best model were employed. Two different approaches were performed to develop a predictive QSAR model: a set with all selected herbicides and a divided set according structure (pyrimidinyl/ triazinyl). QSAR models were analyzed using following statistical parameters: coefficient of correlation, adjusted coefficient of correlation, mean squared error, root mean square error, and Fischer test. Models with four descriptors in both sets of herbicides were statistically better, based on the values of these parameters.

The MOLECULAR CHARACTERIZATION AND GENETIC VARIABILITY IN BREAD, DURUM AND DICOCCUM WHEAT GENOTYPES BASED ON MICROSATELLITE MARKERS

2024-01-14T18:39:56+01:00

Tetraploid wheat species Triticum durum Desf. and Triticum dicoccum Schrank ex Schubler could be unique sources of favorable genes for economically important characteristics like resistance to biotic and abiotic stresses as well as quality characteristics. Molecular characterization and determination of genetic relationship among varieties and hybrid lines of bread, durum and emmer wheat is fundamental for selection of genotypes with desirable traits resilient under climatic fluctuations and development of successful crop improvement programmes. In this study, ten simple sequence repeat (SSR) markers were used to characterize 50 bread, durum, dicoccum wheat genotypes from North Macedonia. In total, 48 alleles were detected with an average of 4.8 alleles per locus. The highest number of alleles per locus was detected in genome D with 5.5, compared to 4.75 and 4.5 for genomes B and A, respectively. The mean PIC values for all 10 microsatellite markers was 0.66 with values ranging from 0.59 for marker Wmc264 to 0.85 for marker Wmc89 that are important for breeding programs. The average genetic diversity based on SSR markers was 0.51 with a range of 0.20 - 0.72. A dendrogram was constructed to determine the genetic relationship and cluster analyses separated tetraploid wheat from hexaploid wheat genotypes. The data could serve as a basis for wheat taxonomy,wheat improvement programmes and further association mapping for important agronomic traits.

CHARACTERIZATION OF CLOVE OIL WITH A FT-IR ATR SPECTROSCOPIC METHOD

2024-01-14T18:42:13+01:00

Clove oil possesses excellent antioxidant and antimicrobial properties, while the main components of clove oil are eugenol, acetyleugenol and caryophyllene. Two types (ground and buds) of clove were used in the analysis. The clove essential oil was obtained using a steam distillation and an ultrasonic assisted extraction method. The separation of eugenol from other components was achieved with benzoyl chloride reaction. The analysis of clove oil was with a FT-IR ATR spectroscopic method along with the use of a TLC method using mobile phases, toluene:ethyl acetate (9.3:0.7 v/v), phase A and chloroform:hexane (1:2 v/v), phase B. The UV-Vis spectrum of eugenol was with maximum at 280 nm. The obtained yield was found to be 8.79% and 12.41% for ground clove and 1.36% and 6.75% for clove buds using ultrasonic assisted extraction method, respectively. The characteristic band for the ester group C-O of eugenol acetate was observed at 1765 cm^-1. The R_f value for eugenol was 0.66 with phase A, and 0.46 using phase B. The methods were easy to be handled, rapid and can be used in the routine analysis.

SPECTROPHОTОMETRIC METHOD FOR DETERMINATION OF TOTAL POLYHENOLIC CONTENT IN SWEET CORN

2024-02-20T19:11:36+01:00

Polyphenolic compounds also known as polyhydroxyphenols, are a group of secondary plant metabolites that can be found as simple molecules but also as highly polymerized compounds such as tannins. Many food types are considered as a great source of polyphenolic compounds, such as fruit, herbs, vegetables, grains and so on. Therefore, the goal of the present study was the determination of total polyphenolic content (TPC) in two sweet corn cultivars Messenger F1 and Sentinel F1 using UV – Vis spectroscopy. TPC in sweet corn are evaluated by Folin – Ciocâlteu method in relation with gallic acid as a reference standard. The obtained results reveled that the TPC in the hybrid Messenger F1 is

GENETIC ANALYSIS OF GROWTH AND FRUIT BEARING TRAITS OF ‘OBLAČINSKA’ SOUR CHERRY CLONES

2024-02-20T10:13:27+01:00

During the three-year period of investigation, the trunk circumference, yield per tree, and yield efficiency in 13 ‘Oblačinska’ sour cherry clones were studied. Significant differences among the studied clones and years of testing were determined for all investigated traits, while interaction clone × year showed no significant differences. The lowest trunk circumference and yield per tree were found in the clone 13 (23.2 cm; 7.6 kg), and yield efficiency in clone 3 (0.09 kg/cm²). Clone 3 had the highest trunk circumference (53.9 cm), clone 6 had the highest yield per tree (23.3 kg), and clone 10 had the highest yield efficiency (0.18 kg/cm²). The lowest coefficients of genetic and phenotypic variation were determined for the yield efficiency (16.69%; 20.46%), and the highest for the yield per tree (33.28%; 34.89%). The coefficient of heritability ranged from 66.20% for the yield efficiency up to 98.37% for the trunk circumference.