https://scientific-jl.com/luch/
Часть-41_ Том-21_ Март-2025
461
THE EFFECT OF MOISTURE ON THE STORAGE OF FLOUR AND
GROATS
senior lecturer O.N. NORBOYEV
QARSHI STATE TECHNICAL UNIVERSITY
Department of “Automation and
control of technological processes”
Anonotatsiya : Ushbu maqolada un va yorma mahsulotlarining saqlashda
namlikning ta’siri o‘rganiladi. Namlik darajasi mahsulotlarning fizik
xususiyatlarini, shu jumladan sochiluvchanlik, g‘ovaklik va sorbsion xossalarini
o‘zgartiradi. Maqolada namlikning oksidlanish va achchiqlanish jarayonlariga
ta’siri, shuningdek mikroorganizmlar rivojlanishi va ularning mahsulot sifatiga
ta’siri ham tahlil qilingan. Yuqori namlikda mikroorganizmlar tez rivojlanib,
mahsulot sifatini yomonlashtiradi, shuning uchun saqlashda namlikni nazorat
qilish muhimdir. Maqolada un va yorma mahsulotlarining issiq-fizik xossalari ham
ko‘rib chiqilib, namlikni nazorat qilishning saqlashdagi ahamiyati ta’kidlangan.
Аннотация: В данной статье изучается влияние влажности на
хранение муки и круп. Уровень влажности изменяет физические свойства
продуктов,
включая
сыпучесть,
пористость
и
сорбционные
характеристики. Также анализируется влияние влажности на процессы
окисления и прогоркания, а также развитие микроорганизмов и их влияние
на качество продукции. При высокой влажности микроорганизмы быстро
развиваются, ухудшая качество продуктов, поэтому контроль влажности
при хранении имеет важное значение. В статье также рассматриваются
теплофизические свойства муки и круп, подчеркивается важность
контроля влажности в процессе хранения.
https://scientific-jl.com/luch/
Часть-41_ Том-21_ Март-2025
462
Annotation: This article examines the impact of humidity on the storage of
flour and cereal products. The humidity level affects the physical properties of the
products, including flowability, porosity, and sorption characteristics. The article
also analyzes the effect of humidity on oxidation and rancidity processes, as well
as the development of microorganisms and their impact on product quality. At high
humidity, microorganisms develop rapidly, deteriorating the product quality,
making humidity control crucial during storage. The article also discusses the
thermophysical properties of flour and cereals, emphasizing the importance of
humidity control in storage.
Key words:
Humidity, flour storage, cereal storage, flowability, porosity,
sorption properties, oxidation, rancidity, microorganisms, product quality,
humidity control, thermophysical properties, moisture saturation, condensation,
gas exchange, insect pests, autolysis, fat hydrolysis, enzymes, proteins, gluten, ash,
vitamins, flour grade, wheat flour, rye flour, cereal products, temperature
fluctuations, ventilation, product spoilage, self-heating, mold, flour rancidity,
humidity regulation.
The role of moisture in the storage of flour and groat products is of great
importance. The processes related to the moisture content of flour, unlike other
factors, stop and even slow down the rancidity of flour. Moisture primarily prevents
the oxidation of flour by limiting the interaction between air and flour. However,
high moisture content promotes the growth of microorganisms, which deteriorates
the quality of the products. The rancidity process of flour is directly dependent on
the moisture content. According to N.N. Sosodova's data, wheat flours with a yield
of 78% begin to deteriorate after four months of storage at moisture levels of 12%,
13%, and 14%, and this process is fully completed by the sixth month. However,
flours with 15-16% moisture did not show rancidity. This explains how moisture
helps prevent oxidation of flour and slows down microbiological processes.
https://scientific-jl.com/luch/
Часть-41_ Том-21_ Март-2025
463
Moisture limits the absorption of air by the flour, which helps prevent oxidation.
However, high moisture content creates ideal conditions for microorganisms to
thrive. Therefore, controlling moisture during the storage of flour is crucial. In
places where flour is stored, sunlight can accelerate the rancidity process, but this
factor does not significantly affect the quality of the flour since it is typically stored
in closed environments. Microorganisms are always present in flour, and under
certain conditions, especially with high moisture, they find a good substrate for
development. Cleaning processes help reduce the number of microorganisms, but
if washing or drying procedures are not done on time, the microbial count may
increase. It is essential to take necessary measures to limit microbiological
processes during storage. Mold growth, souring, or self-heating can occur due to
microbial activity, so it is necessary to prevent such activities during storage.
The flowability of flour and groats also changes under the influence of
moisture. The flowability of flour is lower than that of grains because it consists of
finer particles. As moisture increases, the flowability decreases. At moisture levels
of 16% or higher, flowability significantly decreases. The flowability of groat
products varies depending on the type of grain used. For example, rice groats have
higher flowability compared to rice grains, and barley groats have higher
flowability compared to barley grains.
The porosity of flour and groat products also changes with moisture. Due to
the very fine particles of flour, its porosity consists of small, crack-like voids. This
reduces gas exchange and slows down the activity of harmful insects. As moisture
increases, this porosity is affected, which contributes to the development of
microbiological processes. Therefore, it is essential to consider their physical
properties and control moisture when storing flour and groats.
Flour and groat products can absorb or release moisture, gases, and odors from
the environment. However, the sorption properties of flour and groats are lower
https://scientific-jl.com/luch/
Часть-41_ Том-21_ Март-2025
464
compared to grains, primarily due to their smaller porous structure. Flour and groat
products should be cooled before storage, as excess moisture negatively affects
their quality. Temperature fluctuations can lead to the formation of condensation
moisture, which accelerates microbiological processes.
The thermal-physical properties of flour and groat products also interact with
moisture. Like grains, flour, groats, and bran have low thermal conductivity. This
reduces the combined effect of heat and moisture. The retention of moisture and a
drop in temperature can lead to the formation of condensation moisture, which
accelerates microbiological processes. Therefore, storage areas for flour and groat
products should be well-ventilated, and cooling processes should be taken into
account.
The chemical composition, nutritional value, and technological quality of
flour primarily depend on the type of grain, its variety, grinding method, and flour
yield (percentage of grain mass). Currently, the flour industry produces premium,
first-grade, second-grade, and bran flours from wheat. The chemical composition
of premium wheat flour is as follows (%): water – 14, carbohydrates – 73.6,
proteins – 10.8, fiber – 0.2, fats – 0.9, ash – 0.5. For first-grade flour, these values
are 14, 72.9, 11.0, 0.3, 1.1, and 0.7, respectively, while bran flour has 14, 69.6,
11.8, 1.6, 1.5, and 1.5. Bran and second-grade flours contain vitamins V1, V2, RR,
and E, whereas premium and first-grade flours have little to no such vitamins. Flour
contains various enzymes (proteinases, amylases, catalase, lipase, etc.) that
influence the bread-making process and its quality. Rye flours are typically
produced in one grade, as well as 96% one-grade wheat-rye flours (70% wheat,
30% rye) and 95% one-grade rye-wheat flours (60% rye, 40% wheat). Based on
the flour’s yield and grade, the color, powderiness, ash content, gluten quantity,
and quality are standardized. High-quality flour has a distinctive smell and a sweet
taste.
https://scientific-jl.com/luch/
Часть-41_ Том-21_ Март-2025
465
During the storage of flour, its quality may change. In the initial stage, i.e.,
within the first month, flour stored at a high temperature (20-30°C) undergoes a
"ripening" process where the fats undergo hydrolysis and oxidation, which
improves its quality. However, prolonged storage leads to a deterioration in its
quality. The moisture content of flour should not exceed 15%. If moisture
increases, the flour will become rancid, moldy, and self-heat. If moisture is too low
(9-13%), the flour will deteriorate rapidly. Due to its ability to absorb moisture and
odors, flour should be stored in a dry, cool place away from odorous products. For
high-quality flour, the gluten content should be from the first or second group, and
this content should be at least 20-30%.
Conclusion:
The effect of moisture on the storage quality of flour and groat products is
significant. The moisture level alters the physical and chemical properties of the
products, including flowability, porosity, and sorption characteristics. Moisture
controls the oxidation of flour and the development of microbiological processes,
while high moisture promotes the growth of microorganisms, leading to a decline
in product quality. It is essential to maintain balanced moisture levels during
storage, as high moisture can promote microbial growth, while low moisture can
cause rapid deterioration of flour. Therefore, it is crucial to control moisture levels
and storage conditions when storing flour and groat products. Temperature,
moisture, microbiological processes, and the chemical composition of the product
should all be considered, as these factors directly influence the quality of flour and
groat products.
Literature
1.
Uljayev, E., Ubaydullaev, U. M., Narzullayev, S. N., & Norboyev,
O. N. (2021). Application of expert systems for measuring the humidity of bulk
https://scientific-jl.com/luch/
Часть-41_ Том-21_ Март-2025
466
materials.
International Journal of Mechatronics and Applied Mechanics
, (9),
131-137.
2.
Ulzhaev, E., Narzullaev, S. N., & Norboev, O. N. (2021, January).
Substantiation of application of artificial neural networks for creation of humidity
measuring devices. In
Euro-Asia Conferences
(Vol. 1, No. 1, pp. 86-91).
3.
Norboev, O. N., Farxodov, S. U., Eshonqulov, M. N., & Ibragimov,
B. S. (2021). Mathematical model of a high-frequency moisture mete forcotton
seeds based on substitution schemes.
Web of Scientist: International Scientific
Research Journal
,
2
(05), 674-686.
4.
Ulzhaev, E., Narzullaev, S. N., Norboev, O. N., & Abdikhalilov, O.
U. (2021, March). MOISTURE METER FOR POWDER BULK MATERIALS.
In
Euro-Asia Conferences
(Vol. 3, No. 1, pp. 115-117).
5.
Narzullayev, S. (2022). NECESSITY OF GRADUATION AND
CALIBRATION OF MOISTURE METERS.
Open Access Repository
,
8
(2), 5-8.
