https://doi.org/10.52973/rcfcv-e34356
Received: 26/11/2023 Accepted: 21/01/2024 Published: 01/04/2024
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Revista Científica, FCV-LUZ / Vol. XXXIV, rcfcv-e34356
ABSTRACT
This study investigates the impact of freeze–thaw cycles on samples
of Sardinella aurita, focusing on the examination of physicochemical
properties, water–holding capacity, color changes, and histological
alterations in sh meat. The present ndings indicate signicant
variations in the studied parameters, i.e., pH, water activity, lightness
(L*), redness (a*), yellowness (b*), protein solubility (mg·g
-1
), moisture
content (%), thawing loss (%), centrifugation loss (%), cooking loss (%),
underscoring the importance of comprehending the consequences
of freezing–thawing in the shing and food processing industry.
Initially, a statistically signicant decrease in pH levels was observed
(T0: 6.23 ± 0.1, T4: 6.19 ± 0.1), followed by a notable increase after
the fth freeze–thaw cycle (T5: 6.47 ± 0.1), possibly due to chemical
and microbiological composition shifts. Water activity exhibited a
gradual decrease (T0: 0.911 ± 0.009, T4: 0.899 ± 0.01), likely attributed
to water loss during freezing–thawing (P<0.05). Colorimetry results
demonstrated a signicant decrease in brightness (L*) and a slight
increase in yellow hue (b*) throughout the cycles, with values
ranging from 63.51 (T0) to 33.64 (T5) for L* and from 26.74 (T0) to
17.28 (T5) for b*. These variations highlight notable and signicant
changes in the product’s color over the freeze–thaw cycles (P<0.05).
Histological analysis revealed structural changes, including muscle
ber dehydration. These observed changes hold implications for
product quality and consumer perception. It is essential to recognize
that various factors, such as sh size, seasonality, and environmental
conditions inuence these results. Further research is needed to
delve deeper into these aspects. In essence, this study offers valuable
insights for industry professionals, aiding them in making informed
decisions regarding seafood products subjected to freezing–thawing
cycles. This not only ensures product quality and safety but also
helps prevent food fraud and provides consumers with high–quality
products.
Key words: Sardinella aurita; histological changes; freeze–thaw
cycles; water–holding
RESUMEN
Este estudio investiga el impacto de los ciclos de congelación y
descongelación en muestras de Sardinella aurita, centrándose en
el examen de propiedades sicoquímicas, capacidad de retención
de agua, cambios de color y alteraciones histológicas en la carne del
pescado. Los hallazgos actuales indican variaciones signicativas en
estos parámetros [pH, actividad de agua, luminosidad (L*), rojez (a*),
amarillez (b*), solubilidad de proteínas (mg·g
-1
), contenido de humedad
(%), pérdida de descongelación (%), pérdida por centrifugación
(%), pérdida de cocción (%)]. Los resultados revelan alteraciones
significativas en estos parámetros, destacando la importancia
de comprender los efectos de la congelación y descongelación
en la calidad del pescado dentro de la industria pesquera y de
procesamiento de alimentos. Inicialmente, se observó una disminución
estadísticamente signicativa en los niveles de pH (T0: 6.23 ± 0.1, T4:
6.19 ± 0.1), seguida de un aumento notable después del quinto ciclo (T5:
6.47 ± 0.1), posiblemente debido a cambios en la composición química y
microbiológica. La actividad del agua mostró una disminución gradual,
probablemente atribuida a la pérdida de agua durante la congelación y
descongelación (P<0,05). Los resultados de la colorimetría mostraron
una disminución significativa en la luminosidad (L*) y un ligero
aumento en el tono amarillo (b*) a lo largo de los ciclos, con valores
que van desde 63.51 (T0) hasta 33.64 (T5) para L* y desde 26.74 (T0)
hasta 17.28 (T5) para b*. Estas variaciones resaltan cambios notables
y signicativos en el color del producto a lo largo de los ciclos de
congelación y descongelación (P<0,05) Estos cambios observados
tienen implicaciones en la calidad del producto y la percepción del
consumidor. Es importante reconocer que estos resultados están
inuenciados por diversos factores, como el tamaño del pescado, la
estacionalidad y las condiciones ambientales. Se necesita investigación
adicional para profundizar en estos aspectos. En resumen, este estudio
proporciona información valiosa para los profesionales de la industria,
ayudándolos a tomar decisiones informadas sobre productos de mar
sometidos a ciclos de congelación y descongelación. Esto no solo
garantiza la calidad y seguridad del producto, sino que también ayuda
a prevenir el fraude alimentario y proporciona a los consumidores
productos de alta calidad.
Palabras clave: Sardinella aurita; cambios histológicos; ciclos de
congelación y descongelación; retención de agua
Effect of freeze–thaw cycles on the physicochemical, water–holding
properties, and histology of Sardinella aurita
Efecto de los ciclos de congelación y descongelación en las propiedades sicoquímicas,
capacidad de retención de agua y la histología de Sardinella aurita
Mounia Megaache , Omar Bennoune*
University of Batna 1, Institute of Veterinary and Agricultural Sciences, Department of Veterinary Sciences, Laboratory of Health, Animal Production and
Environment. Batna, Algeria.
*
Corresponding author: omar.bennoune@univ–batna.dz
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INTRODUCTION
Consumer interests related to food safety and quality are paramount
when selecting sh for purchase, and this holds true on a global scale
[1, 2]. Consumers are increasingly vigilant when choosing sh, driven
by concerns that the sh they buy may have undergone alterations.
These alterations may involve opting for thawed sh rather than
fresh ones [2, 3]. After death, sh undergo signicant chemical and
bacterial changes that render them more suitable for consumption,
as highlighted in a study [4]. Furthermore, assessing the quality of
frozen sh takes into account the condition of the sh before the
freezing process [5, 6]. Certain sh species have a limited shelf
life due to their low protein, fat, and moisture levels, as well as the
presence of microorganisms [4, 7]. The shelf life of such sh has
been extended through the development of methods for freezing
perishable raw materials, enabling long–term storage. Freezing is
one of the most common processes employed in the food industry
today to preserve the quality of meat and other food products over
time [8]. It leads to the deceleration of many biochemical reactions,
resulting in alterations in food quality. Additionally, freezing reduces
water activity, a critical aspect of the freezing process that inhibits
microbial growth [9]. It also induces changes in muscle structure,
impacting the overall sensory quality of shery products [10, 11].
In 2018, It was reported that ice crystals formed in muscles during
freezing cause irreversible structural damage to muscle bers and
myobrils [12]. This damage is attributed to changes in muscle
morphology and size due to the formation of ice crystals, which
occur at varying rates depending on the freezing speed of the meat
[13]. Freezing meat can impair its quality by denaturing proteins and
aggregating them into larger masses. Both [14] and [15] found that this
deterioration in quality persists even after thawing. This persistence
is attributed to the formation of ice crystals during the freezing
process, which can damage the structure of proteins, leading to
their denaturation. Protein denaturation, in turn, alters their functional
properties, affecting their ability to bind water, solubility, and three–
dimensional structure. Notably, the inuence of protein denaturation
on the texture, avor, and juiciness of meat persists even after the
sh has been thawed. When assessing sh meat quality, it is essential
to consider its fat content. When discussing the fat content of food,
reference is made to the quantity of healthy fats it contains, a factor
proven to benet human health [16]. Fish meat loses quality when it
oxidizes or is frozen and stored for extended periods [17]. The rate
of meat spoilage is contingent on the release of fatty acids without
interference from lipases responsible for breaking down sh proteins.
[17] and [3] corroborated this fact. Moreover, the water content of
meat affects its taste and texture after defrosting or refreezing.
Freezing sh muscles alters their structure and composition, as
indicated by histological analysis and chemical assessments.
By collecting data related to these aspects, the current study aims
to demonstrate the effect of freezing on the muscles of Sardinella
(Sardinella aurita). This introduction provides an overview of the
primary factors that have led to the undertaking of this study on
the impact of freezing on the quality of sh products in Algeria. It
underscores the growing importance of food safety and product
quality for consumers, as well as the challenges associated with
preserving the freshness of sh products in a context where freezing
has become commonplace.
MATERIALS AND METHODS
Sampling
Histological evaluation was carried out on a total of 30 fresh samples
of Sardinella aurita, obtained from El–Kala shing port, Algeria,
with a weight of about 111.25 g and a length of 25 cm and brought
refrigerated to the Laboratory of Histology and Histopathology of the
University of Batna 1 within 12 hours of being caught. All samples were
individually wrapped in polyethylene bags and randomly divided into 6
groups; the rst group with zero freeze–thaw cycle (T0 (fresh), while
the samples of the other ve groups were subjected to freezing at
-20°C for different days (d) (4 d, 7 d, 11 d, 15 d, and 20 d) separated by
thawing at 4°C for 12 hours to obtain samples with different freeze–
thaw cycles, i.e., T1 (one freeze–thaw cycle), T2 (two freeze–thaw
cycles), T3 (three freeze–thaw cycles), T4 (four freeze–thaw cycles),
T5 (ve freeze–thaw cycles). The microstructure of meat tissues was
observed after thawing.
Physicochemical properties
• pH measurement
The pH values were measured according to the technique described
by Li et al. [18] and the samples were prepared by mixing 10 g of sh
with 90 mL distilled water. The pH values were measured using an
inoLab® digital pH meter (Xylem Analytics, WTW, Weilheim, Germany).
• Water activity (Aw)
Water activity (Aw) was measured with a Hygroscope Rotronic
model BT–RS1.
• Color
A colorimeter (Konica Minolta CR–10, Japan) was used to evaluate the
color changes due to freeze–thaw cycles. To ensure a comprehensive
representation, as reported by Ali et al. [19], measurements included
brightness (L*), redness (a*), and yellowness (b*) and they were
recorded at three distinct locations on the surface of each of the
six sh samples.
• Protein solubility
One gram of fish sample underwent homogenization using a
Wiggins D–500 homogenizer (Straubenhardt, Germany) and treated
as described by Choi et al. [20]. The homogenized sample was then
mixed with 20 mL of ice–cold KI/potassium phosphate and left at a
temperature of 4°C overnight. Afterward, the mixture underwent
centrifugation (B. Braun Sigma 2K15 Centrifuge, Germany) (2,000G) at
4°C for 20 min. Following this, a combination of 2 mL of the supernatant
and 8 mL of a biuret solution was prepared and added. The absorbance
of this solution was subsequently measured at a wavelength of 540
nm with a spectrophotometer (Shimadzu UV 120–01, Japan).
Water holding capacity
• Moisture content (%)
The water content of various commodities was largely assessed
through oven drying method, and represent the difference between
the initial weight of samples (10 g) and their subsequent weight after
oven drying at 37°C for 3 d as reported by Avinee et al. [21].
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To assess how well samples, retain water, we measured thawing
loss, centrifugation loss, and cooking loss, with some minor changes
to the methods reported by Zhu et al. [22]. Specically, we modied
the assessment of centrifugation loss by using 2 g samples instead
of the 10 g mentioned by Zhu et al. [22]. Additionally, in the evaluation
of cooking loss, we standardized the sample weight to 5 g.
• Thawing loss (%)
After the meat had thawed, the liquid in the package was poured
out, and the samples of meat were wiped down with paper towels and
weighed again. The freezing loss was measured as a percentage of the
difference between the amount of weight lost before and after freezing.
• Centrifugation loss (%)
Two grams of sh samples, enclosed in lter paper, were loaded
into a centrifuge tube and subjected to centrifugation at 210 G at 4°C
for 10 min. The weight difference between the samples before and
after centrifugation was used to calculate the centrifugation loss.
• Cooking loss (%)
To gure out how much food was lost during cooking, 5 g of samples
were measured, wrapped in heat–resistant foil paper, and put in a
water bath at 80°C for 30 min. The internal temperature was not
measured, but based on an earlier study [23], it was estimated that
it would take 30 min to reach the best internal temperature of 75 to
80°C. Samples are left out to dry and then weighed.
Histological and morphometric analysis
After preliminary microscopic examination of hematoxylin and eosin
(H&E) stained sections, ve hot spot areas of the samples were selected
at low power magnication and measurements were made at 100X
using a free software, ImageJ (version 1.52a). These measurements
included average area of vacuoles, average area of myobers containing
vacuoles, and the ratio of total vacuole area to cell area were calculated
to perform quantitative analysis of vacuoles with freeze–thaw cycles.
Statistical analysis
Statistical analysis was performed on the observed values by the
application of variance (ANOVA) using SPSS software version 26 (IBM
SPSS Statistics v26). Comparison of means was performed using the
Tukey method. The difference is considered statistically signicant
when P<0.05 and considered nonsignicant when P>0.05.
RESULTS AND DISCUSSION
Physicochemical properties
The freezing–thawing cycles appear to have an effect (P<0.05) on
the pH of Sardinella aurita samples (TABLE I). After several cycles,
the pH showed a downward trend, followed by a signicant increase
in the fifth cycle. This may indicate changes in the chemical or
microbiological composition of the sh due to the repeated freezing–
thawing process.
The elevation in volatile basic components is what causes the pH
to increase during storage. The latter acknowledges earlier research
presented [18, 24]. The development of ice crystals at -20°C may give
rise to the release of intracellular components, resulting in the highest
pH value observed in sample T5. Similar ndings have been reported
by other authors [24, 25, 26]. pH values of sh can be inuenced by
various factors, including species, size, season, water composition,
during location, stress levels during shing, and muscle type [18].
The water activity values indicate a gradual decrease in water
availability in sardinella samples over the freezing–thawing cycles (T0:
0.911 ± 0.009, T4: 0.899 ± 0.01), with some minor variations (TABLE I).
This reduction may be attributed to water loss during the freezing–
thawing process. Monitoring water activity is important as it can
impact the microbiological stability and texture of food products.
The variations in water activity are related to uid migration and ice
crystallization [27]. Signicant differences (P<0.001) in water activity
were observed in the abdominal and dorsal muscles of carp after
freezing [1]. This study highlights a decrease in water activity after
the rst freezing, followed by an increase after the second freezing,
TABLE I
Changes in physiochemical and water–holding properties of Sardinella aurita subjected to multiple freeze–thaw cycles
Traits T0 T1 T2 T3 T4 T5
Physicochemical properties
pH 6.23 ± 0.10
a
6.17 ± 0.08
a
6.20 ± 0.10
a
6.15 ± 0.10
a
6.19 ± 0.10
a
6.47 ± 0.10
b
Water activity 0.911 ± 0.009
a
0.909 ± 0.005
a
0.903 ± 0.010
a
0.900 ± 0.010
a
0.899 ± 0.010
a
0.920 ± 0.010
a
L* value (lightness) 63.51 ± 11.01
c
58.77 ± 11.18
bc
45.61 ± 16.49
abc
42.48 ± 38.53
abc
38.53 ± 15.50
ab
33.64 ± 15.63
c
a* value (redness) -9.27 ± 2.82
a
-8.17 ± 2.82
ab
-7.90 ± 2.70
ab
-6.80 ± 2.37
abc
-5.80 ± 2.76
bc
-5.05 ± 2.56
c
b* value (yellowness) 26.74 ± 3.06
c
25.48 ± 3.06
bc
21.36 ± 5.51
abc
20.00 ± 5.48
abc
18.94 ± 5.76
ab
17.28 ± 5.87
a
Protein solubility (mg/g) 15.99 ± 1.28
a
14.58 ± 0.43
ab
13.64 ± 0.84
b
12.7 ± 1.25
bc
11.23 ± 1.25
c
8.88 ± 0.80
d
Water–holding properties
Moisture content (%) 78.68 ± 1.23
b
78.10 ± 1.97
b
76.90 ± 1.97
b
74.70 ± 0.60
a
74.08 ± 1.28
a
73.18 ± 1.34
a
Thawing loss (%) 0.78 ± 0.27
a
1.35 ± 0.49
bc
1.54 ± 0.69
bc
2.12 ± 0.67
cd
3.28 ± 1.04
d
Centrifugation loss (%) 8.64 ± 0.70
a
10.20 ± 3.09
a
15.84 ± 1.87
b
17.98 ± 1.59
bc
19.68 ± 1.77
bc
20.00 ± 1.58
c
Cooking loss (%) 13.72 ± 2.30
a
15.28 ± 0.40
ab
19.00 ± 20.4
bc
20.40 ± 1.70
c
21.20 ± 1.30
c
22.22 ± 1.69
c
Note: T0: fresh meat; T1: one freeze–thaw cycle; T2: two freeze–thaw cycles; T3: three freeze–thaw cycles, T4: four freeze–thaw cycles, T5: ve freeze–
thaw cycles. Data are given as mean values ± standard deviation (n = 5). Means within a row with dierent superscripts dier signicantly (
P<0.05)
FIGURE 1. Muscle histology of Sardinella aurita subjected to dierent freeze–thaw
cycles. (H&E, 100×). a: T0(fresh meat); b: T1(one freeze–thaw cycle); c: T2(two freeze–
thaw cycles); d: T3(three freeze–thaw cycles); e: T4(four freeze–thaw cycles); f:
T5(ve freeze–thaw cycles). 1. perimysium internum; 2. skeletal muscle bers with
normal histostructure; 3. shrunken skeletal muscle bers; 4. completely destructed
skeletal muscle bers; 5. skeletal muscle bers with broken central and retained
peripheral part; 6. interstitial protein material; 7. vacuoles; 8. Endomysium
Effect of freeze-thaw cycles on Sardinella aurita / Megaache and Bennoune _______________________________________________________
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regardless of the muscle type (dorsal or ventral). In contrast, our own
results demonstrate a decrease in water activity over the rst four
cycles of freezing–thawing, followed by an increase in the fth cycle.
These variations could be attributed to specicities related to the
types of sh studied and experimental conditions.
The colorimetry results reveal that sardinella samples subjected to
freezing–thawing cycles undergo signicant color changes (TABLE I).
Brightness progressively decreases, indicating a darkening of the
samples. The values of the (a*) component (redness) show signicant
variations, indicating a gradual increase from T0 to T5, while the yellow
hue (b*) slightly increases. Uncertainty varies among samples, which
may reect measurement variability. These color changes can have
signicant implications for the quality and perception of the nal product.
Proteins in sardinellas exhibit a gradual decrease in solubility
following freezing–thaw cycles (TABLE I). This reduction in solubility
is likely due to the effect of freezing and thawing on the protein’s
structure. The decrease in protein solubility may potentially affect
the texture and quality of the nal product. In a study conducted by
Careche and his team [28] signicant drops in the solubility of soluble
proteins were observed in cod llets at both -20°C and -30°C, with a
more pronounced decrease at -20°C.
Water–holding capacity
The results show variability in the moisture content of sardinella
samples subjected to freezing–thawing cycles. Initially, at T0
(fresh sh), the average moisture content was 78.68%, indicating a
substantial presence of water in the samples. However, after the rst
two cycles (T1 and T2), while the moisture content remained relatively
high, a slight non–signicant reduction was observed compared to T0.
The signicant variation occurred from the third cycle (T3) onwards,
where the moisture content started to decrease signicantly, reaching
74.7% at T3 and 74.08% at T4. This downward trend continued with the
fth cycle (T5), where the moisture content reached 73.18%. (TABLE I).
These variations may be inuenced by freezing, thawing, and storage
processes, as well as other environmental factors. According to other
studies [29], the inability of muscle bers to absorb water during
thawing is the reason for the loss of water content after freezing. The
melting of ice crystals positioned between muscle bers is thought
to be the source of this water. The effect of freeze–thaw cycles on
Sardinella aurita water content is substantial (P<0.05).
The thawing loss, measured in percentage, progressively increases
as the samples undergo more freezing–thawing cycles (TABLE I). At
T1, the thawing loss is 0.78% with an uncertainty of ± 0.27%. This
loss increases at T2, T3, T4, and reaches 3.28% at T5. This trend
indicates that the samples lose water during the thawing process.
The centrifugation loss, also measured in percentage, signicantly
increases as the samples undergo freezing–thawing cycles (TABLEI).
At T0, the centrifugation loss is 8.64% with an uncertainty of ± 0.7%.
This loss increases at T1, T2, T3, T4, reaching 20% at T5. This trend
indicates that the samples have progressively more diculty retaining
water during the process.
The cooking loss, also measured in percentage, significantly
increases with freezing–thawing cycles (TABLE I). At T0, the cooking
loss is 13.72% with an uncertainty of ± 2.3%. This loss increases at
T1, T2, T3, T4, reaching 22.22% at T5. This trend indicates that the
samples lose a signicant amount of water during cooking, which
can affect the quality of the product.
Histological analysis
Central and peripheral muscle bers remained unchanged. No
muscle bundles or muscle bers appeared partially or completely
fragmented (FIG. 1a). Instead, cross–sliced muscle bers appeared
polygonal in shape. Lyu et al. [30] found that sh muscle bers in
bundles have a polygonal shape and appear uniform when non–frozen.
Strateva [1] noted that the carp muscle bers lack torn bits when
positioned uniformly. Dehydrated muscle fibers were observed
with reduced morphological changes. Discarded muscle bers with
complete disruption of shape were also observed. Contracted muscle
bers were observed to be more abundant than bers that maintained
their integrity or completely disrupted in shape (FIG. 1b) When ice
crystals form in the outside space, new osmotic pressure variations
arise. Dehydration of muscle bers can be seen via visual observation
of reduced muscle volume. Strateva [1] determined that muscle bers
diminish in size due to osmotic processes and ice in the extracellular
spaces. As a result of both of these impacts, a perpetual stream of
water moves from the most internal region of muscle bers to the
outermost perimeters. Interstitial protein material in the form of a
distinct basophilic granular substance is evident between muscle
bers (FIGS. 1c, 1d, 1e, 1f). A similar substance has been found in Carp
and Merluccius sh [1, 31]. This protein–based substance is found in
the intercellular space of these sh. Deformed muscle tissue merged
into one gure as it was severely dehydrated and degenerated. This
appeared to be the result of losing the ability to contact, which caused
FIGURE 2. Mean area of ice crystals to dierent freeze–thaw cycles. T1: one
freeze–thaw cycle; T2: two freeze–thaw cycles; T3: three freeze–thaw cycles,
T4: four freeze–thaw cycles, T5: ve freeze–thaw cycles. Dierent letters show
a statistically signicant dierence (P<0.05)
FIGURE 3. Ratio of the ice crystal surface to the cell surface. T1: one freeze–thaw
cycle; T2: two freeze–thaw cycles; T3: three freeze–thaw cycles, T4: four freeze–
thaw cycles, T5: ve freeze–thaw cycles. Dierent letters show a statistically
signicant dierence (P<0.05)
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by a larger increase in cell area with subsequent cycles. Furthermore,
all samples demonstrated the same trend. When ice is stored frozen,
its volume and size recrystallize. This process was well explained by
Jiang et al. [32], during subsequent storage, small ice crystals will
melt and grow into larger ones. This causes light melting of large
crystals that can then grow again [33]. Ice damage to muscle bers
causes increased extracellular migration of water and thawing losses.
Jiang et al. [32] stated that this led to increased protein denaturation
when ice crystals form. Also, increased solute in the remaining water
leads to further protein destruction, according to Kaale et al. [34].
the tissue to appear stiff (FIG. 1c). The size of cracks in the frozen
material made it unlikely that crack patterns lined up with muscle
bers and bunched muscles. Kiani and Sun [9] found that large frozen
crystals produced larger cracks. Additionally, the protein and vacuoles
between the muscle bers blurred their edges and contours. Freezing
and thawing processes reduced signicantly the amount of skeletal
muscle tissue. Furthermore, the size and number of open spaces
increased dramatically lling more areas (FIG. 1d, 1e, 1f)
Histomorphometric analysis
Quantitative analysis of ice crystal sizes (FIG. 2) and volumes was
performed by calculating the ratio of the size or volume of a sh’s
ice crystals to the sh’s cell surface area (FIG. 3). However, this was
dicult for one part of the analysis; since some sh were thawed and
some bers were disrupted (T4 and T5). Calculating sh cell surface
areas showed to be much easier than calculating ice crystal surface
areas. Although there was signicant difference (P<0.05) between rst
(603,63 μm
2
) and fth cycles (3954,18 μm
2
), the trend remained the
same a signicant increase in cell area with the rst cycle followed
CONCLUSIONS
To summarize, this extensive investigation into the impact of
freeze–thaw cycles on Sardinella aurita samples has uncovered
noteworthy alterations in physicochemical characteristics, water
retention, color, and histological structure of the sh. These ndings
emphasize the signicance of comprehending how freezing–thawing
affects sh quality, especially within the context of the shing and
food processing industry, with a view to thwarting food fraud. pH
measurements indicate changes in pH after multiple cycles. Initially, a
downward trend was observed, followed by a signicant increase in the
fth cycle. Additionally, water activity values show a gradual decrease
in water availability in sardine samples over the freezing–thawing
cycles, with some minor variations. Furthermore, there is a color
changes, that are not noticeable to most consumers. Additionally,
histological changes such as muscle ber desiccation can exert an
inuence on the sh’s texture. It is important to acknowledge that
these results may be inuenced by various factors, such as the size
of the sh, seasonal uctuations, and environmental conditions. As
a result, further investigations could explore these aspects to gain
a more profound understanding of the underlying mechanisms. In
essence, this study offers valuable insights for professionals in the
shing and food processing sector, enabling them to make informed
decisions regarding the management of seafood products subjected
to freezing–thawing cycles. Such measures not only assure product
quality and food safety but also serve as a deterrent against food
fraud for the benet of consumers.
Conict of interests
The authors declared no potential conflicts of interest with
respect to the research, authorship, and/or publication of this article.
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