Wheat Grain Storage Research Articles

THE EFFECT OF THE ELECTROMAGNETIC FIELD OF EXTREMELY LOW FREQUENCIES ON THE QUALITY OF WHEAT GRAIN

The paper presents the results of studies of how the electromagnetic field (EMF) of extremely low frequencies (ELF), magnetic induction of the EMF, and the duration of processing and storage affect the quality characteristics of wheat grain of the cultivar Shestopalivka harvested in the Odesa Region in 2018, 2019, and 2020. Treatment of grain with the EMF of the frequencies 20 and 30 Hz and with magnetic induction of 5 and 10 mT for 2–20 min reduces the germination capacity of wheat, as compared with the control, by 1–12%. As an exception, in several experiments, the germination capacity increased. The biggest increase (by 14%) was observed when the duration of treatment was 12 minutes, the frequency 30 Hz, and the magnetic induction 5 mT. Treatment of grain for 6 min with the EMF at the frequencies 10–28 Hz and with magnetic induction showed that at 10, 18–24 Hz, the germination capacity increased by 1–5%, but after 15 days, at the frequency 12–26 Hz, the germination power increased by 1–9%. A month later, with the frequency 18, 20, and 28 Hz, the germination power exceeded the control by only 2–7%, and after 10 months of storage, only the experiment with the frequency of treatment 24 Hz was at the control level. With all other frequencies, there was a significant decrease in grain germination. It has been established that treating grain 15 days prior to sowing at 14–22 Hz increases the germination capacity by 7–9%, and it reaches the values 92–94%. In the grain treated with the EMF at 10–30 Hz and stored for 14 months at the controlled air temperature 9–23°C and the relative humidity 33–82.5%, the protein content on a dry basis did not change compared with the control (16.5%). Storage of grain treated for 6 minutes with an EMF at 10–30 Hz, the magnetic induction being 10 mT, allows increasing the gluten content by 1.07–1.21 times, as compared with the control. The biggest increase in the amount of gluten is achieved at the frequency 16 Hz. Even under unfavourable conditions, at the temperature 23°C and relative air humidity 82.5%, the gluten quality goes up by 27.65 conditional units of the device VDK (1.49 times) and becomes as high as the gluten quality of grain that was preserved under far better conditions, at 9°C and the humidity 33 %. When grain is EMF-treated for 6 min at 10–30 Hz, with the magnetic induction being 10 mT, under different storage conditions, this most often affects the content of stearic and gondoic acids. The biggest changes in them were noted during storage at 9°C and the relative air humidity 82%: gondoic acid increased by 12.5–18.7%, and stearic acid decreased by 15.5–25.0%. Under any other conditions of EMF treatment and storage of wheat grain, changes in fatty acids are within the allowable error.

Изменение биохимических и физико-химических показателей продовольственного зерна пшеницы в процессе длительного лабораторного хранения

The results of changes in the biochemical and physico-chemical quality indicators of food grain of wheat crops in 2015 and 2018 are presented during long-term laboratory storage at elevated (+ 30°C), moderate (+ 20°C), and low (+ 10°C) temperatures at standard humidity for wheat grain (no higher than 14%). We found that food storage of wheat grain impacted at different temperatures for 19 months leads to a natural increase in the acid number of the fat (ANF) at different initial values, which indicates the preservation of lipase activity and the possibility of using this indicator to establish the terms of safe storage and shelf life.

Comparative study on storage behaviour of wheat in different storage bags

A hermetic storage bags is a safe, cost-effective storage method that controls insect infestations in addition to preserving the quality of grains, while allowing for pesticide-free, short-term and long-term qualitative and quantitative seed preservation, without refrigeration, maintaining seed vigor and pest control. Hermetic bags need to be validated for its effectiveness in hermetic storage of food grains under Bihar condition. The present study was undertaken in response to requests by farmers, traders and private seed companies to determine the effectiveness of hermetic bags for storage of wheat grain. Hence, a comparative study on storage behavior of wheat in different storage bags was made to assess the qualitative and quantitative loss and to validate the advantages of hermetic super grain bags over the conventional storage bags used in the region. Fresh and healthy wheat seeds were cleaned and graded. The experiment consisted of seven treatments using four different types of bags – Hermetic grain bags, Polythene bags, Jute bags and Plastic bags by using one chemical fumigant (Aluminium Phosphide) and dried Neem leaves. There was no any treatment in grain stored in hermetic grain bag. For neem treatment, the fresh neem leaves were taken from the tree and dried by sun drying method. The fumigant (Aluminium Phosphide) popularly known as sulphash were used. was taken and following consideration is drawn from the study, The variation in grain moisture content, water activity and germination percent of wheat was least in the hermetic grain bag while maximum in Jute bag. Germination percentage of wheat stored was maximum in super grain bag throughout the storage period than other storage modes/treatments. The variation in colour index was least in super grain bag showing the minimal effect of ambient condition to the stored wheat grain. Wheat can be stored under ambient conditions up to 3 months in hermetic storage bag with minimum qualitative and quantitative loss. There is no requirement of any chemical treatment of grains stored in hermetic super bags as the micro environment developed is sufficient enough to restrict the growth of pests, insects and micro-organism.

Tri5 gene expression analysis during postharvest storage of wheat grain from field plots treated with a triazole and a strobilurin fungicide

Fusarium head blight (FHB) and the associated mycotoxin deoxynivalenol (DON) negatively impact the wheat industry worldwide. In North America, FHB is mainly caused by Fusarium graminearum sensu stricto. The purpose of this study was to evaluate, under storage conditions, the expression of the DON biosynthetic gene trichodiene synthase (Tri5) of F. graminearum in grain of hard red winter wheat cultivars ‘Overley’ (FHB-susceptible) and ‘Overland’ (moderately resistant to FHB) from field plots treated or untreated with the triazole fungicide Prosaro and the strobilurin fungicide Headline. Infected grain was stored and periodically sampled to determine gene expression by qRT-PCR analysis. The F. graminearum housekeeping gene GAPDH was consistently detected, indicative of metabolically active fungi, and Tri5 detection was significantly higher in ‘Overley’ compared with ‘Overland’. Tri5 gene expression and DON concentrations showed little to no correlation; consequently, Tri5 expression levels did not accurately predict DON concentrations. The strobilurin did not significantly reduce Tri5 gene expression compared with untreated wheat. In the triazole treatment, a significant reduction in the relative expression of Tri5 was detected after 120 days, as well as a downregulation of Tri5 from 60 to 120 days of storage in ‘Overley’. In grain from strobilurin-treated plots of both cultivars, the expression of Tri5 increased from 0 to 30 days after tempering. Genetic expression of Tri5 that is necessary for the production of DON can increase during storage of high-moisture grain. Fusarium fungi can persist in wheat kernels for several months postharvest and may actively produce toxin during this period.

Management of air flows inside steel silo during grain storage

A study was conducted concerning effects of temperature and relative air humidity during long-term storage of wheat grain in a steel silo. The study was aimed at identifying the possibility of condensed moisture appearing under the silo roof. The probable periods of condensate in the space under the silo roof depending on the temperature difference inside and outside the silo have been determined. Some ways to prevent the condensate formation are proposed in the paper.

Methodology for assessing the grain mass thermal effusivity in a metal silo under the influence of active ventilation

The purpose of studying the thermal effusivity of the grain mass in a metal silo is to obtain a dynamic mathematical model of the processes of layered changes in the temperature of the grain mass under the influence of an external factor. Such an external factor is the supply of cooling air through the air distribution grid of the bottom of the silo with the active ventilation of grain in a metal silo. The created mathematical and parametric models allow simulating the moisture transfer process using active air ventilation systems inside metal silos during storage of wheat grain. There have been developed some ways to improve the conditions for ensuring the quality preservation of grain during its long-term storage in a metal silo. It is necessary to load such a silo with grain completely, preferably up to the top, leaving free supergrannial space as small as possible. Another solution is thermal insulation of the surfaces of the silo. The task of ensuring the safety of wheat food grain can be accomplished not only on the basis of existing regulatory rules, but also by taking into account the results of new research. The main method of storage in metal containers, according to the instructions and safety regulations is the storage of grain in a dry and purified state. It is known that not only humidity and purity, but also the temperature of the grain put into storage affect the storage period.

Determination of Major Factors Associated with Fungal Contamination of Wheat Under Storage Conditions

Storage fungi are among the major factors causing post-harvest deterioration of crop produce worldwide. However, their association to the major factors that contribute to fungal contamination under storage conditions remains under studied in many parts of Sub-Saharan Africa including Ethiopia. Therefore, the current work was carried out with the objectives to identify major factors that contribute to fungal contamination of wheat grains under storage conditions. For this purpose mycological analysis was carried out using 180 wheat grain samples collected from three major wheat growing zones (Arsi, West Arsi and Bale) of South East Ethiopia. Results of the mycological analysis revealed the contamination of wheat grains by fungal species at different locations and storage time with different frequencies. Fungal contamination of samples indicated that highest incidence was observed at West Arsi (96.98%) followed by Bale (91.76%) and Arsi (86.43%). Fungal contamination also varied with storage period with the highest incidence of (98.62%) followed by (89.78%) and (86.77%) was observed after six months, upon harvest and three months of storage, respectively. The highest fungal incidence (98.62%) was recorded after six months storage of wheat grain. Fungal incidence was highly associated with two of the independent variables, namely, temperature and relative humidity of storage in a logistic regression model. However, there is no significant association (p<0.05) with grain moisture content and storage type of wheat grains under storage conditions.

Retention of deoxynivalenol and its derivatives during storage of wheat grain and flour

Fate of deoxynivalenol (DON) and its derivatives—deoxynivalenol-3-glucoside (D3G), 15-acetyldeoxynivalenol (15-AcDON) and 3-acetyldeoxynivalenol (3-AcDON) during six-month storage of wheat grain and flour was investigated. Wheat grain and flour polluted by DON, D3G, 15-AcDON and 3-AcDON were packaged in polyethylene bags, kraft paper bags and cloth bags, and stored at room temperature and 4–6 °C, and mycotoxin levels were analyzed by UPLC-MS/MS after storing for 30, 90 and 180 days. Levels of DON, 15-AcDON and 3-AcDON in wheat grain showed a generally decrease during the storage duration, and DON concentrations averagely decreased by 40–50%. An obviously increase of DON (more than 70%) and decrease of 15-AcDON and 3-AcDON were observed after storage in wheat flour. There were no significant differences of D3G levels in most of wheat grain and wheat flour samples after storage, but some increased dramatically with retention level up to 240%. The results suggested conversion of DON and its derivatives may occur during wheat grain and flour storage.

Genetic control of lutein esterification in wheat (Triticum aestivum L.) grain

Lutein is a naturally occurring plant carotenoid compound that is also an important micro-nutrient for humans. While the biosynthesis of lutein in bread wheat (Triticum aestivum L.) is well understood, in contrast, there is little information on the mechanism or the genetic control involved in conversion of lutein to lutein esters during storage of wheat grain. The purpose of this research was to investigate the genetic control of lutein ester formation in wheat.Lutein esterification varied between accessions of bread wheat, some related species and even grain tissues. A single locus controlling lutein esterification (designated Lute) was mapped on the short arm of chromosome 7D using a mapping population derived from zero-ester and high-ester parents. A GDSL-like lipase gene was identified in a syntenic region of the rice genome and wheat sequences with similarity to that gene were genetically mapped at the same position as Lute.Since lutein esters seem to be more stable than free lutein, improved understanding of the genetics and biochemistry of lutein esterification could be useful for optimising the retention of lutein during the storage, handling and processing of wheat and other products that contain this important micronutrient.

Mold-inhibitory activity of different yeast species during airtight storage of wheat grain

The yeast Pichia anomala J121 inhibits spoilage by Penicillium roqueforti in laboratory and pilot studies with high-moisture wheat in malfunctioning airtight storage. We tested the biocontrol ability of an additional 57 yeast species in a grain mini silo system. Most yeast species grew to CFU levels comparable to that of P. anomala J121 after 14 days of incubation (>10(6) CFU g(-1)). Of the 58 species, 38 (63 strains) had no mold-inhibitory effects (Pen. roqueforti levels >10(5) CFU g(-1)). Among these were 11 species (18 strains) that did not grow on the wheat grain. Several of the non-inhibiting yeast species have previously been reported as biocontrol agents in other postharvest environments. Weak inhibitory activity, reducing Pen. roqueforti levels to between 10(4) and 10(5) CFU g(-1), was observed with 11 species (12 strains). Candida silvicola and Pichia guillermondii reduced Pen. roqueforti to <10(4) CFU g(-1). Candida fennica, Candida pelliculosa, Candida silvicultrix, P. anomala (29 strains), Pichia burtonii, Pichia farinosa and Pichia membranifaciens strongly inhibited Pen. roqueforti (<10(3) CFU g(-1)) in the mini silos, but none had higher biocontrol activity than P. anomala strain J121. This report is the first of biocontrol activity of C. fennica and C. silvicultrix. The ability of 27 yeast species to grow to high CFU values without inhibiting mold growth suggests that nutrient competition may not be the main mode of action of P. anomala J121.

The influence of α‐amylase supplementation, γ‐irradiation (60Co) as well as long time of storage of wheat grain on flour technological properties

AbstractThe varieties of winter wheat, Aria and Beta, were studied. The Aria variety was stored for the period of four years. The part of wheat grain from Beta variety was irradiated with γ rays (60Co). In extracts from wheat kernels and flour protein content, total α‐ and β‐amylolytic activity as well as α‐amylolytic activity were determined. α‐amylases of native and fungal origin were added to the flour obtained from samples of stored wheat kernels (Aria), irradiated and non‐irradiated (Beta). Consequently native α‐amylase activity of flour increased by 25 % and 50% respectively. Extensive technological estimation of grain and flour with amylase supplements was carried out. The study included: sedimentation analysis, falling number test, milling experiment, farinogram and extensogram analyses, measurement of the degree of damaged starch and flour colour, as well as baking experiment. The obtained experimental loaves of bread were tested for their ability to remain fresh. It was found out that the stored grain flour was characterized by the highest α ‐amylolytic activity and the lowest falling number value, whereas the irradiated grain flour showed the highest degree of starch damage and water absorption. When α‐amylase supplementation to doughs wasn't accompanied either by irradiation or storage of grain, it definitely changed their physical properties for the worse. The negative influence of native α‐amylases appeared to be less significant than that of fungal α‐amylases. The positive influence of α‐amylase supplementations, especially of those increasing by 25 % the native α‐amylolytic activity of flour on volume, and freshness of loaves of bread was observed.