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Article

Comparative Effect of GABA and 1-MCP in Maintaining Strawberry Fruit Quality During Cold Storage

by
Mihaela Iasmina Madalina Ilea
,
Huertas María Díaz-Mula
,
Alba García-Molina
,
María Celeste Ruiz-Aracil
,
Christian Fernández-Picazo
and
Fabián Guillén
*
Postharvest Research Group of Fruit and Vegetables, Instituto de Investigación e Innovación Agroalimentario y Agroambiental (CIAGRO-UMH), University Miguel Hernández, Ctra. Beniel km. 3.2, 03312 Orihuela, Spain
*
Author to whom correspondence should be addressed.
Horticulturae 2025, 11(4), 370; https://doi.org/10.3390/horticulturae11040370
Submission received: 28 February 2025 / Revised: 26 March 2025 / Accepted: 28 March 2025 / Published: 30 March 2025
(This article belongs to the Section Postharvest Biology, Quality, Safety, and Technology)
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Abstract

:
Strawberries (Fragaria x ananassa Duch.) are highly perishable fruits with a short postharvest shelf life, requiring effective preservation techniques. This study evaluates the efficacy of γ-aminobutyric acid (GABA) and 1-methylcyclopropene (1-MCP) in maintaining strawberry quality during cold storage. Freshly harvested strawberries were treated with different concentrations of GABA (1–20 mM), and a commercial 1-MCP concentration was suggested for strawberries (250 nL L⁻1) before being stored at 2 °C for up to 12 days. Different quality, physiological, and biochemical parameters were evaluated every 3 days after harvest. Results showed that both GABA and 1-MCP treatments effectively delayed fruit senescence. GABA demonstrated a higher effect on reducing weight loss, around 35.01% and 5.29% for 10 mM GABA and 1-MCP, respectively, compared to control fruit after 12 days at 2 °C. These substances also were effective in preserving firmness, but better maintenance was observed for 10 mM GABA than for 1-MCP (5.11 ± 0.43 and 3.49 ± 0.37 N, respectively) compared with control fruit after 12 days at 2 °C (2.56 ± 0.46 N). On the other hand, lower GABA concentrations (1–5 mM) and 1-MCP were particularly effective in delaying colour evolution and maintaining cell membranes and bioactive compounds such as polyphenols. In conclusion, as a postharvest treatment, GABA potentially offers an alternative or complement to 1-MCP in prolonging strawberry storability. These findings could contribute to developing sustainable strategies to reduce postharvest losses and improve strawberry marketability.

Graphical Abstract

1. Introduction

The strawberries ‘Florida Radiance’ (Fragaria x ananassa Duch.) belongs to the Rosaceae family and the Fragaria genus. Native to Chile and the United States [1,2], strawberries are often called the “Queen of Fruits” and are among the most widely cultivated fruit crops globally. They are highly appreciated by consumers for their delicious taste, delightful aroma, and rich nutritional content [3], as well as for their health-promoting properties, which include a high content of bioactive compounds as polyphenols [4].
Strawberries, characterized as non-climacteric fruits with a very short shelf life, suffer significant postharvest losses of up to 23% before reaching consumers [5]. Due to their high sensitivity to mechanical damage, manual harvesting near the end of ripening is required [2]. During commercial distribution, strawberries are highly susceptible to manipulation and mechanical impact, leading to fruit bruising and skin damage. These injuries increase disease susceptibility, accelerating deterioration and promoting water loss, thus shortening their shelf life.
To maintain quality, it is crucial to apply cold storage or other technologies, with temperature management being the most common method to control senescence. Optimal storage conditions range from 0 to 2 °C with a relative humidity of 90–95% [1,6,7]. However, processing techniques such as individual quick freezing, thermal treatment, and high-pressure processing used to preserve out-of-season strawberries can affect the fruit’s quality, nutritional characteristics, and levels of bioactive compounds due to sensitivity to thermal treatments, enzymatic oxidation, and pectin degradation [8].
Consequently, scientific research focuses on extending postharvest shelf life and developing alternative methods to maintain quality, reduce losses and waste, and ensure consumer satisfaction with fresh products [9].
1-Methylcyclopropene (1-MCP) is a synthetic compound that acts as an ethylene inhibitor, commercially used to slow fruit ripening and extend shelf life during harvest, storage, and transport [10]. It interacts with ethylene receptors, blocking ethylene-dependent responses, and under standard temperature and pressure conditions, it is a gaseous compound with minimal risk to human health, as described by Watkins [11]. Research has also shown that 1-MCP helps preserve the firmness, delaying senescence in non-climacteric fruits such as grapes [12] and tangerines [13]. For strawberries, postharvest commercial application of 1-MCP has been well established [14], delaying ripening parameters and displaying a lower anthocyanin accumulation compared to untreated fruit, preserving fruit firmness and reducing decay [11,15].
γ-aminobutyric acid (GABA) is a four-carbon amino acid that does not participate in protein synthesis and, like several of its structural isomers, is found in both animals and plants. It is an elicitor in physiological and biochemical systems in plants, involved in the stress response in different fruit species such as strawberries, pears, apples, and pistachios [4,16,17,18,19], regulating reactions and supplying additional ATP for cells [20]. The GABA shunt is a metabolic pathway that skips two steps of the tricarboxylic acid (TCA) cycle and is present in both prokaryotes and eukaryotes. This metabolic pathway is stimulated by abiotic and biotic factors, increasing the supply of metabolic substrates to the TCA cycle and the mitochondrial electron transport chain. This process helps maintain cellular energy balance through ATP production while reducing the accumulation of reactive oxygen species [21].
Recently, the effect of GABA on the marketability of strawberry fruit after almost two weeks of storage [4] and during storage at room temperature [22] has been studied. However, its impact during the postharvest storage period remains unclear during cold storage. For these reasons, the main objective of this study was to evaluate the effect of different GABA concentrations on strawberries throughout postharvest storage and compare it with a commercial treatment using 1-MCP.

2. Materials and Methods

2.1. Plant Material and Experimental Design

Strawberries (Fragaria x ananassa Duch.) were harvested in a commercial plot in Huelva, Spain, and at commercial ripeness (>70% of the surface was red, indicating ripening). After harvesting, the strawberries were quickly transported to the laboratory of Miguel Hernández University, where homogeneous fruits (1500 strawberries) were selected based on size, colour, and absence of defects. Following selection, the strawberries were sanitized in 3 min immersion baths containing 10 ppm sodium hypochlorite. They were then organized into 6 lots of 60 strawberries per sampling date, divided into three replicates of 20 strawberries each, with an additional batch of 60 fruits reserved to assess their initial condition upon arrival at the laboratory on day 0. The applied treatments involved freshly prepared immersions of GABA (Sigma-Aldrich, Madrid, Spain) at different concentrations (0 mM (control), 1 mM, 5 mM, 10 mM, and 20 mM) for 10 min containing 0.05 % tween 20 (Sigma-Aldrich, Madrid, Spain). Furthermore, one batch of strawberries underwent treatment with 1-MCP (250 nL L−1) for 24 h. The optimal dosage of 1-MCP for these fruits was determined based on previous studies by Jiang et al. [14]. Applying 1-MCP treatments based on commercial tablets released this compound at the specified dose in 130 L airtight containers. These tablets were provided by Smart FreshSM (AgroFresh Inc., Philadelphia, PA, USA). Following treatment, the strawberries were allowed to air-dry at room temperature for 30 min before being placed in cold storage conditions at 2 °C at a relative humidity of 90% for different periods: 0, 3, 9, and 12 days.

2.2. Postharvest Quality Parameters

Respiration and ethylene concentration were evaluated in triplicate for 10 randomly selected strawberries from each treatment (n = 3). This process involved placing the strawberries in a hermetically sealed container with a capacity of 1 litre for 60 min. Following this duration, 1 mL of gas sample was extracted in duplicates from the septum’s headspace, and the amounts of ethylene and carbon dioxide generated were measured using a Shimadzu GC 2010 gas chromatograph and Shimadzu 14B (Shimadzu Europa GmbH, Duisburg, Germany), respectively. The respiration rate was expressed as mg of CO2 kg−1 h−1, while ethylene production was quantified as nmol kg−1 h−1.
Weight loss was assessed individually for each strawberry by calculating the loss percentage compared to the initial weight (day 0) using a digital balance KERN 440–35N (Balingen, Germany). Also, fruit firmness was evaluated individually for each strawberry using a texture analyzer TX-XT2i (Stable Microsystems, Godalming, UK) equipped with a Magness–Taylor probe (5 mm diameter) capable of measuring texture by inserting the probe into the strawberry pulp. This probe has an insertion length of 5 mm into the fruit pulp at a speed of 1.0 mm s −1. Firmness was quantified as the maximum load pressure in Newtons (N) applied at the highest point of the fruit. Results were reported as mean ± SE (n = 3).
Colour evaluation was performed using the CIELAB system (L*, a*, b*), employing a Minolta CR400 tri-stimulus colourimeter. It was expressed as lightness (CIE L*), colour saturation (CIE C*), and colour tone (CIE hue*). Three colour measurements were taken for each fruit at three equidistant points along the equator.
The total chlorophyll content (TCC) was assayed in duplicate for each replicate (n = 3) within the fresh calyx of strawberries. A homogeneous mixture of the calyces (1 g) was extracted using 20 mL of 99% methanol (MeOH). Following extraction, the samples underwent centrifugation (10,000 rpm, 10 min), and the resulting supernatant was analysed using a spectrophotometer (1900 UV/Vis, Shimadzu, Kyoto, Japan) at wavelengths of 665.2 nm and 652.4 nm. The results were expressed and quantified following the equations provided by Vu et al. [23] as mg 100 g−1 and reported as mean ± SE.
The total polyphenol content (TPC) was determined using the Folin–Ciocalteu method [24], obtaining the supernatant from the mixture of 1 g of sample with 20 mL of phosphate buffer (10,000 rpm, 10 min) obtained per triplicate. We followed the method described by Lezoul et al. [24] to obtain the results of the strawberry samples conducted in triplicate. The absorbance of the samples was measured using a spectrophotometer (1900 UV/Vis, Shimadzu, Kyoto, Japan) at 760 nm. The results were expressed as milligrams of gallic acid equivalent per unit weight of the sample (e.g., 100 g) and reported as mean ± SE (n = 3).
Electrolyte leakage (EL) was evaluated in triplicate using 20 cylinders in each replicate (n = 3), each measuring 3 mm in diameter and 4 mm in thickness. This procedure was conducted for each treatment, following the methodology outlined by Hwang et al. [25], with specific modifications. The discs were independently subjected to three consecutive 3 min immersions in 50 mL of deionized water with constant agitation for one hour. Following this period, the initial values (C1) of electrical conductivity (EC) were measured. Subsequently, the samples were autoclaved at 100 °C for 15 min, and after this process, they were cooled at 20 °C. The final conductivity values (C2) were then determined. The calculation was carried out to express electrolyte leakage as a percentage (EL = (C1/C2) × 100).
The malondialdehyde (MDA) content in strawberry pulp was determined following the method described by Zhang et al. [26]. Exactly 0.2 g of pulp were extracted with 10 mL of 1% trichloroacetic acid (TCA). Subsequently, the sample was centrifuged (10,000 rpm, 10 min), and 0.5 mL of the supernatant was used for the reaction with 1 mL of 20% TCA and 0.5 mL of 1% thiobarbituric acid (TBA). The mixture was placed in a water bath (95 °C, 30 min), followed by cooling, and the MDA value of the strawberry was determined using a spectrophotometer (1900 UV/Vis, Shimadzu, Kyoto, Japan) at wavelengths of 450 nm, 532 nm, and 600 nm. The results were expressed as µmol kg−1.
Other parameters, such as total soluble solids (TSS) and titratable acidity (TA), were assessed in duplicate using filtered juice from the mixture of 50 g of strawberries in each replicate and batch. Total soluble solids were quantified using a digital refractometer (Atago PR-101, Atago Co. Ltd., Tokyo, Japan). At the same time, titratable acidity was measured through automatic titration (mod785 DMP Titrino, Metrohm, Herisau, Switzerland) with 1 mL of juice mixed with 25 mL of deionized water. The results for both parameters were expressed as g 100 g−1 and reported as mean ± SE (n = 3).

2.3. Statistical Analysis

In this study, the results were expressed as mean ± standard error (SE), and the experiment was conducted under a completely randomized design. Analysis of variance (ANOVA) was performed. When the differences shown by the different samples, represented as storage days for each treatment, were significant (p < 0.05), the mean values ± SE were compared using Tukey’s HSD test. In graphs, different lowercase letters express significant differences among the applied treatments. All data analyses were conducted using the SPSS software package, version 22.0 for Windows (IBM Corp.; Armonk, NY, USA).

3. Results and Discussion

3.1. Respiration and Ethylene Production

Strawberries have a short commercial shelf life due to their high metabolic activity, particularly at room temperature, accelerating quality deterioration. During postharvest storage, strawberries exhibit a constant rate of CO2 production maintained until the end of storage, increasing specifically at the end of this study (Figure 1A).
However, 1-MCP, after 12 days of storage and GABA treatments during the complete study, reduced the respiration rate significantly (p < 0.05) compared with the control fruit. Similarly, while traditionally described as producing low to moderate levels of ethylene, this hormone shows a distinct production pattern throughout the fruit’s development. Ethylene production in strawberries is moderately low during the green stage, drops further in the white stage, and rises again during the red ripening phase. This coincides with an increased respiration rate, similar to climacteric fruits at the start of ripening. While strawberries are generally classified as non-climacteric, some research indicates they may display climacteric-like behaviour under specific conditions, such as postharvest colour changes in nearly ripe or fully red stages [27]. In our study, ethylene production was affected by all the chemical treatments, reducing ethylene production specifically with the different GABA concentrations applied (Figure 1B). Comparing the 1-MCP effect with the GABA applications on the different fruit batches, GABA impacts ethylene production significantly (p < 0.05) delaying this parameter during cold storage compared with control and 1-MCP batches. The effect of 1-MCP and GABA treatments reducing ethylene in strawberries could affect different quality parameters, determining strawberry commercial distribution and storage life. For this reason, several authors have not considered strawberries as entirely non-climacteric fruit because, in strawberries, the expression of specific genes related to ripening is controlled by ethylene, affecting the postharvest physiology of this fruit [28,29]. Applying 1-MCP and GABA has distinct effects on respiration rate and ethylene production in plant species. 1-MCP reduces respiration by blocking ethylene receptors, slowing down physiological processes in fruits and vegetables. On the other hand, exogenous GABA increases the GABA pathway activity, stimulating the tricarboxylic acid cycle and maintaining the cell energy status with a shorter pathway. In this regard, ATP production is more efficient and has lower oxygen consumption, thereby reducing respiration rates despite stimulating the TCA cycle [30]. This action supports the different biochemical changes affecting the ripening process. Moreover, in strawberries and other fruits sensitive to Botrytis cinerea infection, the fungus can produce ethylene during its pathogenesis. This fungal-derived ethylene may play a role in accelerating fruit deterioration and further complicates the interplay between ethylene dynamics and the postharvest quality of these fruits during storage [31]. In our study, under the applied storage conditions, we did not observe visible effects on microbial growth in this strawberry cultivar across the experiment. However, surface collapse and bruising developed during storage, creating favourable conditions for microbial incidence.

3.2. Weight Loss and Fruit Softening Evolution

Weight loss and fruit softening are key factors in strawberry quality during postharvest commercialization due to their quick impact on strawberry appearance, texture, consumer acceptance, and shelf life. In our study, both 1-MCP and GABA treatments delayed both parameters compared to the control fruit, although this delay was mainly significant (p < 0.05) for GABA treatments (Figure 2).
1-MCP treatments delayed weight loss significantly (p < 0.05) after 3 days of cold storage compared to control fruit batches. However, the higher GABA concentrations applied (10 and 20 mM) effectively controlled the weight loss during the study (Figure 2A) even after 12 days of storage at 2 °C. A higher weight loss is generally related to lower fruit firmness in fruits and vegetables. In this study, fruit softening was significantly (p < 0.05) delayed by GABA treatments as compared to 1-MCP and control batches (Figure 2B). Despite this, in general, 1-MCP batches did not show differences. However, during the complete study, medium fruit firmness values in 1-MCP batches were consistently higher than in the control group (p > 0.05).
Weight loss and fruit firmness are strongly related. Weight loss, in general, is affected by transpiration and metabolic processes, including respiration. For this reason, the positive effect observed in 1-MCP strawberry batches could be due to a lower metabolism. Additionally, lower weight loss is related to the maintenance of fruit firmness in strawberries [32]. Jiang et al. [14] have previously observed the 1-MCP effect on fruit firmness with a strong impact related to the 1-MCP concentration applied and its effect, reducing ethylene production, even in this fruit classified as non-climacteric, coinciding with our results. Lower ethylene production is related to lower enzymatic breakdown of cell wall components in fruits and vegetables [11]. On the other hand, GABA treatments have successfully reduced weight loss and fruit firmness in many plant species, such as guava, lemon, and avocado fruit [33,34,35]. In strawberries, Zhang et al. [4] did not find any effect on fruit firmness, although, after 12 days of storage, they found a lower weight loss in 10 mM GABA-treated strawberries. However, in our study, all GABA concentrations (1–20 mM) maintained fruit firmness and reduced weight losses, especially the higher ones. The better effect of higher concentrations may be attributed to their stronger ability to slow down respiratory metabolism and reduce ethylene production in the fruit, as has been described previously in this study for 10 mM GABA applications. The different cultivars and conditions applied may explain the different results observed. Supporting our results, several studies have demonstrated that exogenous GABA improves the antioxidant balance, which is critical for maintaining the cell membrane integrity, thus reducing transpiration and fruit softening [4,19]. For this reason, the effect of GABA and 1-MCP on membrane integrity was studied in the following section.

3.3. EL and MDA Content

During postharvest storage, the deterioration of cellular membranes significantly affects fruit firmness and transpiration. The disruption of the lipid composition in membrane cells increases their permeability and leads to uncontrolled ion leakage, which is essential for maintaining cellular and osmotic stability. This process accelerates postharvest quality losses. The highest EL values were generally recorded for control batches during the whole storage period (Figure 3A).
After 3 and 6 days of storage, these values were 7.7% and 5.61%, respectively, higher than those observed for 1-MCP-treated fruit. Regarding GABA treatments, specifically for 10 mM concentration values, they were 16.08% and 17.77% lower than the control fruit after 3 and 6 days of storage. In this regard, all GABA concentrations delayed significantly (p < 0.05) the EL increase during the study compared to control batches. Additionally, the lowest GABA concentration displayed a similar pattern to that observed for 1-MCP-treated fruit. Our results are consistent with Tian et al. [36], who observed that 1-MCP reduced the ethylene effect, reducing ionic leakage in strawberries. Although this is the first time that the GABA effect is described as reducing EL in this fruit, this could be attributed to maintaining antioxidant balance, as has been observed in different fruits, such as strawberries [4], which could delay the membrane lipid peroxidation. For that reason, MDA content was evaluated because it is the main byproduct of lipid peroxidation.
High MDA levels indicate lower membrane integrity. The MDA content in strawberries increased during storage, but all the different chemicals applied delayed the MDA accumulation compared to control batches (Figure 3B). Although the effect was similar for 1-MCP and GABA treatments at day 3 of storage, GABA treatments were more effective than 1-MCP in reducing MDA accumulation after 6 days of cold storage and until the end of the study. The lowest MDA levels were recorded at GABA 5 and 10 mM and were 56.40% and 41.81% lower, respectively, compared with the control fruit after 12 days of storage. Our results align with the 1-MCP effect reported in many other fruit species [37,38]. This reduced MDA accumulation could maintain cell membrane integrity through a lower metabolism, as we have described with some parameters in this study. Regarding GABA applications, similar results were observed by Zhang et al. [4] in strawberries. However, in this study, we observed only a reduced accumulation after 12 days of storage with GABA concentrations lower than 10 mM. In contrast, in the present study, significant (p < 0.05) MDA reductions compared with control batches were evident across all applied GABA concentrations throughout the entire storage period, suggesting reduced oxidative stress in strawberry tissues.

3.4. Colour Parameter Evolution in Strawberry Fruit During Storage

The different colour parameters for strawberry quality evaluated in this study (CIE L*, CIE C*, and CIE hue*) declined during refrigerated storage (Figure 4). The CIE L* parameter, which represents the brightness of the strawberries, showed a general decreasing trend across all treatments (Figure 4A).
The control group and the higher GABA concentrations applied (10–20 mM) exhibited the most important reductions in CIE L*, indicating a pronounced darkening of the fruit over time. In contrast, strawberries treated with 1-MCP maintained higher CIE L* values, suggesting that this treatment helped preserve brightness. Similarly, GABA treatments at lower concentrations than 10 mM contributed to maintaining fruit brightness, specifically the lowest concentrations applied (1–5 mM). Regarding CIE C* (colour intensity), the control group experienced a significant decrease as storage progressed, indicating a reduction in colour saturation (Figure 4B). This decline was less pronounced in strawberries treated with 1-MCP, effectively preserving colour intensity throughout the storage period and performing similarly to GABA treatments. Among the GABA treatments, the lower concentrations applied (1–5 mM) yielded the highest values, maintaining CIE C* values similar to those observed in 1-MCP-treated strawberries. In contrast, GABA 10 mM resulted in a trend pattern similar to that of the control fruit, indicating that lower concentrations had a weaker effect on preventing the loss of colour intensity. The CIE hue* angle, which reflects changes in colour tone (and lower values are due to changes related to darkening), also declined over time, suggesting that strawberries became redder as they ripened. The control group exhibited the most rapid decline, indicating a more advanced senescence process (Figure 4C). In contrast, 1-MCP-treated strawberries showed a slower reduction in CIE hue*, suggesting a delay in colour evolution. Similarly, GABA at low concentrations (1–5 mM) exhibited a significant (p < 0.05) improvement effect on 1-MCP, maintaining similar values to those at harvest time, potentially extending fruit freshness. These results can be visually verified in Figure 5, where the effectiveness of the different treatments assayed on external appearance was also observed.
The decrease in all the colour parameters has been explained for strawberries as a result of moisture loss, which decreases CIE L* values and the decrease in CIE C* and CIE hue* due to the degradation of different polyphenols, such as anthocyanins, which are present in high concentrations in strawberries [39]. The 1-MCP and GABA treatments in this study have been described as practical tools to reduce weight loss, directly affecting the CIE L* parameter and delaying colour evolution. Our results were supported by different studies which have elucidated that the 1-MCP application and the increase in GABA content delay bioactive compounds degradations involved in fruit-colour-reducing metabolism and senescence in climacteric or non-climacteric fruit and vegetables [11,40]. The 1-MCP has been described as having a multifactorial effect, reducing ethylene production and delaying cell wall degradation. Both effects can preserve the strawberry colour, delaying chlorophyll degradation through a lower ethylene exposition and polyphenol degradation through better tissue integrity and reduced ROS content [14]. Additionally, GABA effectiveness in maintaining strawberry colour could be due to the lower metabolism, as a lower respiration and ethylene production, as was described in this study, combined with maintenance of bioactive compounds such as chlorophylls and polyphenols, as has been studied in the following section. This GABA potential has been evaluated in different fruit species, supporting our results [41]. However, previously, other authors did not find changes related to colour in strawberries after similar GABA applications [4]. These differences between studies could be related to the fact that, while our study analysed the evolution of parameters over time, previous findings only evaluated colour at the end of the commercial period.

3.5. Effect of 1-MCP and GABA on TCC in Strawberry Calyces and TPC in the Pulp Tissues

As expected, the TCC in strawberry calyces progressively decreased during cold storage due to the natural degradation of photosynthetic pigments during postharvest senescence (Figure 6A).
However, significant differences were observed, depending on the treatment applied. In particular, strawberries treated with 1-MCP exhibited a slower reduction in chlorophyll levels in their calyces compared to the control group, suggesting that this compound delayed chlorophyll degradation. This pattern could be related to the lower ethylene production observed previously in our study after 9 days of 1-MCP application and coincident with the results obtained in other non-climacteric fruits and vegetables [11,37]. On the other hand, treatments with GABA demonstrated greater efficacy in preserving chlorophyll content in the calyces, especially at lower concentrations (1–10 mM). The application of GABA at 5 and 10 mM significantly (p < 0.05) slowed down chlorophyll loss compared to the control and 1-MCP-treated fruits. This effect could be attributed to the effective role of GABA in reducing physiological parameters, such as ethylene production. Additionally, other authors have observed an increased resilience of chloroplasts through an enhanced antioxidant balance, reducing ROS and thus maintaining the structural integrity of different tissues, such as thylakoids [42]. This improved antioxidant status has been recently described in GABA-treated strawberries [4]. In the present study, the lower MDA levels in GABA and 1-MCP-treated fruits can be associated with a higher antioxidant status.
Other antioxidant compounds associated with a balanced antioxidant system are polyphenols. The TPC in strawberries followed a dynamic pattern during cold storage, initially increasing and reaching its peak on day 9, followed by a subsequent decline until the end of the storage period (Figure 6B). This trend, characterized by an initial accumulation of polyphenols followed by degradation, has been previously documented in strawberries. Polyphenols such as anthocyanins are synthesized during postharvest through the flavonoid and anthocyanin pathways [43]. When comparing the different treatments, 1-MCP-treated strawberries exhibited a delay in polyphenol degradation compared to the control group, suggesting that this compound may act as a modulator of enzymatic reactions involved in polyphenol breakdown. This effect has also been observed in pears during storage, increasing polyphenol content [44]. However, after 9 days of storage, the polyphenol levels in 1-MCP-treated batches declined more sharply, potentially linked to the observed lower ethylene production at this time point (Figure 1B). Supporting these findings, the effect of 1-MCP reducing the PAL enzyme and thus reducing anthocyanin accumulation was described by Villarreal et al. [29]. GABA-treated strawberries displayed the highest polyphenol accumulation, with the lowest GABA concentrations (1–5 mM) maintaining significantly (p < 0.05) higher polyphenol levels than both control and 1-MCP-treated fruits. The role of 1-MCP in delaying polyphenol degradation is attributed to its ability to reduce ethylene production, which slows down enzymatic pathways associated with polyphenol breakdown. However, by day 9, the ethylene production in 1-MCP-treated fruits reached particularly low levels, potentially limiting polyphenol biosynthesis while still allowing degradation. The superior effect of GABA treatments, particularly at low concentrations, could be because GABA mitigates oxidative stress and modulates metabolic pathways involved in polyphenol synthesis [45]. This mechanism might explain why GABA-treated strawberries exhibited higher polyphenol retention throughout storage, especially at 1–5 mM.

3.6. Effect of 1-MCP and GABA on TSS and TA

TSS and TA continuously decreased during cold storage, with significant differences observed depending on the applied treatment (Figure 7).
Fruits treated with 1-MCP showed a slower reduction in TSS and TA values compared to the control group, mainly after 6 days of cold storage. While 1-MCP effectively delayed TSS and acidity loss during the initial period of storage, higher GABA concentrations (10–20 mM) did not exhibit any significant effect (p > 0.05) compared to the control batches after this period. GABA treatments displayed a variable effect depending on the concentration applied. In particular, lower GABA concentrations (1–5 mM) were more effective in delaying the reduction in TSS and TA, with GABA 5 mM being the most effective treatment compared to the rest of the applied treatments. In contrast, higher GABA concentrations (10–20 mM) only showed significant differences (p < 0.05) at the end of the study compared to the control, suggesting that high doses may not be as effective in maintaining these parameters.
The decrease in TSS and TA in strawberries is associated with the catabolism of soluble sugars and organic acids as respiration substrates [46]. The effect of 1-MCP in slowing TSS and TA loss could be related to the lower ethylene production observed after 1-MCP applications, as ethylene is known to accelerate ripening processes. A similar effect in strawberries was observed in this study and in other strawberry cultivars [46] and other non-climacteric fruits such as pineapple and zucchini [37,47]. Regarding GABA treatments, the observed effect on TSS and TA retention at lower concentrations (1–5 mM) could be associated with the reduced respiration and ethylene production observed after 1-MCP and GABA treatments, delaying senescence compared to control fruits. This effect has been attributed to the role of GABA in regulating energy metabolism and reducing oxidative stress, which helps maintain energetic substrates such as soluble sugars and organic acids [20]. Similar findings have been reported in previous studies on GABA-treated strawberries, where specific doses (5–15 mM) maintained higher TSS and acidity levels [4]. However, in the present study, higher GABA concentrations (10–20 mM) did not significantly improve TSS or acidity retention, suggesting that the effectiveness of GABA depends on its applied concentration and that excessive doses might not contribute to maintaining these parameters. Differences between studies could be attributed to different experimental conditions or the strawberry cultivar used.

4. Conclusions

The present study demonstrates the effectiveness of GABA and 1-MCP in maintaining strawberry fruit quality attributes during cold storage. 1-MCP effectively delayed the loss of important quality parameters, including soluble solids and acidity, particularly during the initial storage period. All applied GABA concentrations contributed to delaying senescence. The higher GABA concentrations assayed effectively reduced respiration rates, minimized weight loss, and preserved fruit firmness. In contrast, lower GABA concentrations achieved the best results regarding fruit colour and general appearance, probably due to the higher cell membrane protection observed in this study. At the single concentration assayed in this study, 1-MCP was less effective than specific GABA concentrations. Notably, GABA demonstrated an effectiveness comparable to 1-MCP, with some concentrations with an improved impact on postharvest preservation. This effect may be attributed to a delayed metabolism and an improved antioxidant system. In this regard, GABA and 1-MCP also affected bioactive compounds in fruit and calyces, reducing oxidative stress and contributing to reduced fruit senescence. Additionally, although 1-MCP provided a significant protective effect, the results indicate that the lower GABA concentrations (1–5 mM) were more effective in extending visual quality during cold storage. These findings highlight the potential of GABA as a promising postharvest treatment, particularly at optimized lower concentrations, offering an alternative or complementary strategy to 1-MCP for prolonging the freshness of strawberries.

Author Contributions

Conceptualization, H.M.D.-M. and F.G.; methodology, H.M.D.-M. and F.G.; software, M.C.R.-A. and H.M.D.-M.; validation, H.M.D.-M. and F.G.; formal analysis, M.I.M.I., H.M.D.-M., M.C.R.-A., C.F.-P. and F.G.; investigation, M.I.M.I., H.M.D.-M., A.G.-M., M.C.R.-A., C.F.-P. and F.G. resources, F.G.; data curation, M.I.M.I., H.M.D.-M. and F.G; writing—original draft preparation, M.I.M.I.; writing—review and editing, H.M.D.-M. and F.G; visualization, M.I.M.I., H.M.D.-M. and F.G. supervision, F.G. and H.M.D.-M.; funding acquisition F.G. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the Spanish Ministry of Science, Innovation and Universities and the European Commission with FEDER funds, project RTI2018-09966-B-100.

Data Availability Statement

Data are contained within the article. Further inquiries can be directed at the corresponding author.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Azam, M.; Ejaz, S.; Naveed Ur Rehman, R.; Khan, M.; Qadri, R. Postharvest Quality Management of Strawberries. In Strawberry—Pre- and Post-Harvest Management Techniques for Higher Fruit Quality; Asao, T., Asaduzzaman, M., Eds.; IntechOpen: London, UK, 2019; p. 22. [Google Scholar]
  2. Branzanti, E.C. Strawberry; Mundi-Prensa: Madrid, Spain, 1989. [Google Scholar]
  3. Wang, L.; Luo, Z.; Yang, M.; Liang, Z.; Qi, M.; Dong, Y.; Xu, Y.; Lin, X.; Li, L. The Action of RED Light: Specific Elevation of Pelargonidin-Based Anthocyanin through ABA-Related Pathway in Strawberry. Postharvest Biol. Technol. 2022, 186, 111835. [Google Scholar] [CrossRef]
  4. Zhang, Y.; Lin, B.; Tang, G.; Chen, Y.; Deng, M.; Lin, Y.; Li, M.; He, W.; Wang, Y.; Zhang, Y.; et al. Application of γ-Aminobutyric Acid Improves the Postharvest Marketability of Strawberry by Maintaining Fruit Quality and Enhancing Antioxidant System. Food Chem. X 2024, 21, 101252. [Google Scholar] [CrossRef] [PubMed]
  5. Kader, A.; Rolle, R. Value of Horticultural Perishable and Their Post-Harvest Losses. In The Role of Post-Harvest Managements in Assuring the Quality and Safety of Horticultural Produce; Food and Agriculture Organization of the United Nations: Rome, Italy, 2004; Available online: https://www.fao.org/3/y5431e/y5431e00.htm (accessed on 1 December 2024).
  6. González, M.D.C.M. Effect of Edible Coatings with Chitosan Nanoparticles and/or Propolis on the Quality and Antioxidant Capacity of Strawberries Fragaria x ananassa. Master’s Thesis, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico, 2019. Available online: http://riaa.uaem.mx/handle/20.500.12055/993 (accessed on 1 December 2024).
  7. Ruiz, M.; Ávila, J.; Ruales, J. Design of a Bioactive Edible Coating for Application on Strawberries (Fragaria vesca) as a Post-Harvest Process. Iberoam. J. Postharvest Technol. 2016, 17, 276–287. [Google Scholar]
  8. Salazar-Orbea, G.L.; García-Villalba, R.; Bernal, M.J.; Hernández, A.; Tomás-Barberán, F.A.; Sánchez-Siles, L.M. Stability of Phenolic Compounds in Apple and Strawberry: Effect of Different Processing Techniques in Industrial Set Up. Food Chem. 2023, 401, 134099. [Google Scholar] [CrossRef]
  9. Taban, A.; Haghighi, T.M.; Mousavi, S.S.; Sadeghi, H. Are Edible Coatings (with or without Essential Oil/Extract) Game Changers for Maintaining the Postharvest Quality of Strawberries? A Meta-Analysis. Postharvest Biol. Technol. 2024, 216, 113082. [Google Scholar] [CrossRef]
  10. Watkins, C.B. Ethylene Synthesis, Mode of Action, Consequences and Control. In Fruit Quality and Its Biological Basis; Knee, M., Ed.; Sheffield Academic Press: Boca Raton, FL, USA, 2002; pp. 180–224. [Google Scholar]
  11. Watkins, C.B. The Use of 1-Methylcyclopropene (1-MCP) on Fruits and Vegetables. Biotechnol. Adv. 2006, 24, 389–409. [Google Scholar] [CrossRef]
  12. Liu, R.; Ji, N.; Zhang, N.; Wang, R.; Li, Y.; Lei, J.; Zhou, R. Postharvest Quality Exploration of “Crystal” Grapes in Karst Mountainous Area: Regulatory Effect of High Concentration 1-MCP Fumigation. Agronomy 2023, 13, 2450. [Google Scholar] [CrossRef]
  13. Qin, Z.; Pan, J.; Li, J.; Sun, J.; Khoo, H.E.; Dong, X. Effects of 1-Methylcyclopropene and Abscisic Acid Treatments on Texture Properties and Microstructures of Postharvest Tangerine (Citrus reticulata cv. Orah). J. Food Process. Preserv. 2022, 46, e16633. [Google Scholar] [CrossRef]
  14. Jiang, Y.; Joyce, D.C.; Terry, L.A. 1-Methylcyclopropene treatment affects strawberry fruit decay. Postharvest Biol. Technol. 2001, 23, 227–232. [Google Scholar] [CrossRef]
  15. Langer, S.E.; Marina, M.; Francese, P.; Civello, P.M.; Martínez, G.A.; Villarreal, N.M. New Insights into the Cell Wall Preservation by 1-Methylcyclopropene Treatment in Harvest-Ripe Strawberry Fruit. Sci. Hortic. 2022, 299, 111032. [Google Scholar] [CrossRef]
  16. Rabiei, V.; Kakavand, F.; Zaare-Nahandi, F.; Razavi, F.; Aghdam, M.S. Nitric Oxide and γ-Aminobutyric Acid Treatments Delay Senescence of Cornelian Cherry Fruits During Postharvest Cold Storage by Enhancing Antioxidant System Activity. Sci. Hortic. 2019, 243, 268–273. [Google Scholar] [CrossRef]
  17. Li, J.; Zhou, X.; Wei, B.; Cheng, S.; Zhou, Q.; Ji, S. GABA Application Improves the Mitochondrial Antioxidant System and Reduces Peel Browning in ‘Nanguo’ Pears After Removal from Cold Storage. Food Chem. 2019, 297, 124903. [Google Scholar] [CrossRef]
  18. Cheng, P.; Yue, Q.; Zhang, Y.; Zhao, S.; Khan, A.; Yang, X.; He, J.; Wang, S.; Shen, W.; Qian, Q.; et al. Application of γ-Aminobutyric Acid (GABA) Improves Fruit Quality and Rootstock Drought Tolerance in Apple. J. Plant Physiol. 2023, 280, 153890. [Google Scholar] [CrossRef] [PubMed]
  19. Saeedi, M.; Mirdehghan, S.H.; Nazoori, F.; Esmaeilizadeh, M.; Saba, M.K. Impact of Calcium and γ-Aminobutyric Acid (GABA) on Qualitative Attributes and Shelf-Life Characteristics of Fresh In-Hull Pistachio During Cold Storage. Postharvest Biol. Technol. 2022, 187, 111863. [Google Scholar] [CrossRef]
  20. Soleimani Aghdam, M.; Jannatizadeh, A.; Luo, Z.; Paliyath, G. Ensuring Sufficient Intracellular ATP Supply and Friendly Extracellular ATP Signaling Attenuates Stresses, Delays Senescence, and Maintains Quality in Horticultural Crops During Postharvest Life. Trends Food Sci. Technol. 2018, 76, 67–81. [Google Scholar] [CrossRef]
  21. Soleimani Aghdam, M.; Naderi, R.; Jannatizadeh, A.; Babalar, M.; Sarcheshmeh, M.A.A.; Faradonbe, M.Z. Impact of Exogenous GABA Treatments on Endogenous GABA Metabolism in Anthurium Cut Flowers in Response to Postharvest Chilling Temperature. Plant Physiol. Biochem. 2016, 106, 11–15. [Google Scholar] [CrossRef]
  22. Zheng, Y.; Han, X.; Zhang, Y.; Qiu, W.; Tao, T.; Xu, Y.; Li, M.; Xie, X.; Sun, P.; Zheng, G.; et al. Preharvest and Postharvest γ-Aminobutyric Acid Treatment Enhance Quality and Shelf Life in Strawberry (Fragaria × ananassa) Fruits. J. Plant Growth Regul. 2025; in press. [Google Scholar] [CrossRef]
  23. Vu, H.T.; Scarlett, C.J.; Vuong, Q.V. Changes of Phytochemicals and Antioxidant Capacity of Banana Peel During the Ripening Process; With and Without Ethylene Treatment. Sci. Hortic. 2019, 253, 255–262. [Google Scholar] [CrossRef]
  24. Lezoul, N.E.H.; Belkadi, M.; Habibi, F.; Guillén, F. Extraction Processes with Several Solvents on Total Bioactive Compounds in Different Organs of Three Medicinal Plants. Molecules 2020, 25, 4672. [Google Scholar] [CrossRef]
  25. Hwang, Y.S.; Min, J.H.; Kim, D.Y.; Kim, J.G.; Huber, D.J. Potential Mechanisms Associated with Strawberry Fruit Firmness Increases Mediated by Elevated pCO2. Hortic. Environ. Biotechnol. 2012, 53, 41–48. [Google Scholar] [CrossRef]
  26. Zhang, M.; Liu, W.; Li, C.; Shao, T.; Jiang, X.; Zhao, H.; Ai, W. Postharvest Hot Water Dipping and Hot Water Forced Convection Treatments Alleviate Chilling Injury for Zucchini Fruit During Cold Storage. Sci. Hortic. 2019, 249, 219–227. [Google Scholar] [CrossRef]
  27. Villarreal, N.M.; Marina, M.; Nardi, C.F.; Civello, P.M.; Martínez, G.A. Novel Insights of Ethylene Role in Strawberry Cell Wall Metabolism. Plant Sci. 2016, 252, 1–11. [Google Scholar] [CrossRef] [PubMed]
  28. Merchante, C.; Vallarino, J.G.; Aragüez, I.; Villarreal, N.; Ariza, M.T.; Martínez, G.A.; Medina-Escobar, N.; Civello, M.P.; Fernie, A.R.; Botella, M.A.; et al. Ethylene is involved in strawberry fruit ripening in an organ-specific manner. J. Exp. Bot. 2013, 64, 4421–4439. [Google Scholar] [CrossRef] [PubMed]
  29. Villarreal, N.M.; Bustamante, C.A.; Civello, P.M.; Martínez, G.A. Effect of Ethylene and 1-MCP Treatments on Strawberry Fruit Ripening. J. Sci. Food Agric. 2010, 90, 683–689. [Google Scholar] [CrossRef] [PubMed]
  30. Ansari, M.I.; Jalil, S.U.; Ansari, S.A.; Hasanuzzaman, M. GABA Shunt: A Key-Player in Mitigation of ROS During Stress. Plant Growth Regul. 2021, 94, 131–149. [Google Scholar] [CrossRef]
  31. Qadir, A.; Hewett, E.W.; Long, P.G. Ethylene Production by Botrytis cinerea. Postharvest Biol. Technol. 1997, 11, 85–91. [Google Scholar] [CrossRef]
  32. Farida, F.; Hamdani, J.S.; Mubarok, S.; Akutsu, M.; Noviyanti, K.; Nur Rahmat, B.P. Variability of Strawberry Fruit Quality and Shelf Life with Different Edible Coatings. Horticulturae 2023, 9, 741. [Google Scholar] [CrossRef]
  33. Badiche-El Hilali, F.; Valverde, J.M.; Díaz-Mula, H.; Serrano, M.; Valero, D.; Castillo, S. Potential Preharvest Application of γ-Aminobutyric Acid (GABA) on Improving Quality of ‘Verna’ Lemon at Harvest and During Storage. Agriculture 2023, 13, 1397. [Google Scholar] [CrossRef]
  34. Chen, H.; Wang, H.; Jiang, X.; Chen, C.; Cheng, Y. Effects of γ-Aminobutyric Acid Treatment on the Quality Properties and Chilling Tolerance of Guava Fruit During Cold Storage. Food Ferment. Ind. 2021, 47, 130–136. [Google Scholar] [CrossRef]
  35. Ruiz-Aracil, M.C.; Valverde, J.M.; Ilea, M.I.M.; Valero, D.; Castillo, S.; Guillén, F. Innovative Postharvest Management for Hass Avocado at the Preclimacteric Stage: A Combined Technology with GABA and 1-MCP. Foods 2024, 13, 2485. [Google Scholar] [CrossRef]
  36. Tian, M.S.; Prakash, S.; Elgar, H.J.; Young, H.; Burmeister, D.M.; Ross, G.S. Responses of Strawberry Fruit to 1–MCP and Ethylene. Plant Growth Regul. 2000, 32, 83–90. [Google Scholar] [CrossRef]
  37. Medina-Santamarina, J.; Serrano, M.; Ruiz-Aracil, M.C.; Ilea, M.I.M.; Martínez-Romero, D.; Guillén, F. A Synergistic Effect Based on the Combination of Melatonin with 1-Methylcyclopropene as a New Strategy to Increase Chilling Tolerance and General Quality in Zucchini Fruit. Foods 2022, 11, 2784. [Google Scholar] [CrossRef] [PubMed]
  38. Nie, X.; Zhao, Y.; Li, Y.; Lv, H. 1-Methylcyclopropylene and Heat Treatment Alleviate Chilling Injury in Purple Sweet Potato by Regulating ROS Homeostasis. Sci. Hortic. 2024, 324, 112606. [Google Scholar] [CrossRef]
  39. Martínez-González, M.d.C.; Bautista-Baños, S.; Correa-Pacheco, Z.N.; Corona-Rangel, M.L.; Ventura-Aguilar, R.I.; Del Río-García, J.C.; Ramos-García, M.d.L. Effect of Nanostructured Chitosan/Propolis Coatings on the Quality and Antioxidant Capacity of Strawberries During Storage. Coatings 2020, 10, 90. [Google Scholar] [CrossRef]
  40. Soleimani Aghdam, M.; Fard, J.R. Melatonin Treatment Attenuates Postharvest Decay and Maintains Nutritional Quality of Strawberry Fruits (Fragaria × ananassa cv. Selva) by Enhancing GABA Shunt Activity. Food Chem. 2017, 221, 1650–1657. [Google Scholar] [CrossRef] [PubMed]
  41. Nazoori, F.; ZamaniBahramabadi, E.; Mirdehghan, S.H.; Rafie, A. Extending the shelf life of pomegranate (Punica granatum L.) by GABA coating application. J. Food Meas. Charact. 2020, 14, 2760–2772. [Google Scholar] [CrossRef]
  42. Babarabie, M.; Zarei, H.; Eskandari, A. The impact of pre-harvest treatment with gamma-aminobutyric acid (GABA) and salicylic acid on vase life and post-harvest traits of tuberose cut flowers. Acta Sci. Pol. Hortorum Cultus 2019, 18, 83–92. [Google Scholar] [CrossRef]
  43. Nguyen, V.T.B.; Nguyen, D.H.H.; Nguyen, H.V.H. Combination effects of calcium chloride and nano-chitosan on the postharvest quality of strawberry (Fragaria x ananassa Duch.). Postharvest Biol. Technol. 2020, 162, 111103. [Google Scholar] [CrossRef]
  44. Yu, W.; Zhang, X.; Yan, W.; Sun, X.; Wang, Y.; Jia, X. Effects of 1-methylcyclopropene on skin greasiness and quality of ‘Yuluxiang’ pear during storage at 20 °C. J. Integr. Agric. 2024, 23, 2476–2490. [Google Scholar] [CrossRef]
  45. Aghdam, M.S.; Flaherty, E.J.; Shelp, B.J. γ-Aminobutyrate improves the postharvest marketability of horticultural commodities: Advances and prospects. Front. Plant Sci. 2022, 13, 884572. [Google Scholar] [CrossRef]
  46. Yang, X.; Yan, R.; Chen, Q.; Fu, M. Analysis of flavor and taste attributes differences treated by chemical preservatives: A case study in strawberry fruits treated by 1-methylcyclopropene and chlorine dioxide. J. Food Sci. Technol. 2020, 57, 4371–4382. [Google Scholar] [CrossRef] [PubMed]
  47. Selvarajah, S.; Bauchot, A.D.; John, P. Internal browning in cold-stored pineapples is suppressed by a postharvest application of 1-methylcyclopropene. Postharvest Biol. Technol. 2001, 23, 167–170. [Google Scholar] [CrossRef]
Horticulturae 11 00370 g001
Figure 1. Respiration rate (mg CO2 kg−1 h−1) (A) and ethylene production (nmol kg−1 h−1) (B), in control fruit or treated with 1-MCP and GABA at different concentrations and stored at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
Figure 1. Respiration rate (mg CO2 kg−1 h−1) (A) and ethylene production (nmol kg−1 h−1) (B), in control fruit or treated with 1-MCP and GABA at different concentrations and stored at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
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Figure 2. Weight loss (%) (A) and fruit firmness (N) (B), in control fruit and treated with 1-MCP or different GABA concentrations during postharvest storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
Figure 2. Weight loss (%) (A) and fruit firmness (N) (B), in control fruit and treated with 1-MCP or different GABA concentrations during postharvest storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
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Figure 3. Electrolyte leakage (%) (A) and malondialdehyde (MDA) content (μmol kg−1) (B), in control fruit and treated with 1-MCP or GABA at different concentrations during postharvest storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
Figure 3. Electrolyte leakage (%) (A) and malondialdehyde (MDA) content (μmol kg−1) (B), in control fruit and treated with 1-MCP or GABA at different concentrations during postharvest storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
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Figure 4. External colour parameter evolution CIE L* (A), CIE C* (B) and CIE hue* (C) evaluated in control fruit and treated with 1-MCP or GABA at different concentrations during storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3). This figure also displays 6 random strawberry fruits after 9 days of storage from each treatment.
Figure 4. External colour parameter evolution CIE L* (A), CIE C* (B) and CIE hue* (C) evaluated in control fruit and treated with 1-MCP or GABA at different concentrations during storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3). This figure also displays 6 random strawberry fruits after 9 days of storage from each treatment.
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Figure 5. Visual aspect of strawberries treated with distilled water (control), 1-MCP at 250 nL L−1 and GABA at different concentrations (1–20 mM), after 9 days of storage at 5 °C.
Figure 5. Visual aspect of strawberries treated with distilled water (control), 1-MCP at 250 nL L−1 and GABA at different concentrations (1–20 mM), after 9 days of storage at 5 °C.
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Figure 6. Total chlorophyll content (TCC, mg 100 g−1) in strawberry calyces (A) and total polyphenol content (TPC, mg GAE 100 g−1) in strawberry fruit (B), in control batches and treated with 1-MCP or GABA at different concentrations during postharvest storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
Figure 6. Total chlorophyll content (TCC, mg 100 g−1) in strawberry calyces (A) and total polyphenol content (TPC, mg GAE 100 g−1) in strawberry fruit (B), in control batches and treated with 1-MCP or GABA at different concentrations during postharvest storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
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Figure 7. Total soluble solids (TSS, g 100 g−1) (A) and total acidity (TA, g 100 g−1) (B) in control fruit and treated with 1-MCP or GABA at different concentrations during storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
Figure 7. Total soluble solids (TSS, g 100 g−1) (A) and total acidity (TA, g 100 g−1) (B) in control fruit and treated with 1-MCP or GABA at different concentrations during storage at 2 °C. Different lowercase letters indicate significant differences (p < 0.05) among treatments for each sampling date. Data are the mean ± SE (n = 3).
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MDPI and ACS Style

Ilea, M.I.M.; Díaz-Mula, H.M.; García-Molina, A.; Ruiz-Aracil, M.C.; Fernández-Picazo, C.; Guillén, F. Comparative Effect of GABA and 1-MCP in Maintaining Strawberry Fruit Quality During Cold Storage. Horticulturae 2025, 11, 370. https://doi.org/10.3390/horticulturae11040370

AMA Style

Ilea MIM, Díaz-Mula HM, García-Molina A, Ruiz-Aracil MC, Fernández-Picazo C, Guillén F. Comparative Effect of GABA and 1-MCP in Maintaining Strawberry Fruit Quality During Cold Storage. Horticulturae. 2025; 11(4):370. https://doi.org/10.3390/horticulturae11040370

Chicago/Turabian Style

Ilea, Mihaela Iasmina Madalina, Huertas María Díaz-Mula, Alba García-Molina, María Celeste Ruiz-Aracil, Christian Fernández-Picazo, and Fabián Guillén. 2025. "Comparative Effect of GABA and 1-MCP in Maintaining Strawberry Fruit Quality During Cold Storage" Horticulturae 11, no. 4: 370. https://doi.org/10.3390/horticulturae11040370

APA Style

Ilea, M. I. M., Díaz-Mula, H. M., García-Molina, A., Ruiz-Aracil, M. C., Fernández-Picazo, C., & Guillén, F. (2025). Comparative Effect of GABA and 1-MCP in Maintaining Strawberry Fruit Quality During Cold Storage. Horticulturae, 11(4), 370. https://doi.org/10.3390/horticulturae11040370

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