- Different preservation techniques used for increasing the shelf life of fruits and vegetables after harvesting: refrigeration and MAP (Athmaselvi et al. - The edible coating could be considered one of the promising technologies that have been used for keeping whole and minimally processed fruit's quality because of their advantages (El-Mogy et al.. - Many researches have been shown the usage of an edible coating based on AV gel for table grapes and nectarine (Martinez-Romero et al. - 2006 and Ahmed et al.2009), which would be one of the most interesting innovative methods in post- harvest treatments and commercial applications.. - AV gel mainly composed of polysaccharides, the mucilage plays as a normal barrier to O2 and moisture, which can increase the rate of food spoilage. - AV gel contains various antibiotic and antifungal components, like quinones and phenolic components (flavonoids) that may be responsible for delaying or inhibition of the growth of microorganisms for food-borne diseases in humans or food spoilage. - The AV gel had an excellent effect as an antifungal against Fusarium oxysporum so, it was more effective for controlling fungal decay in cherry tomatoes (Ortega-Toro et al. - AV gel edible coating showed a reduction in firmness loss, moisture loss, respiratory rate, development in maturity, delay browning index, and microorganism growth (Lin and Zhao 2007).. - Highly valued for its unique flavor and color, several studies reported that physalis fruits are rich in many valuable compounds (Solange et al. - The calyx of Physalis fruit works to prolong the post-harvest life up to 67% when compared to the fruits without calyx and that may be due to the reduction in respiration rate, moisture loss and colour oxidation (Licodiedoff et al. - Edible coating defined as a thin layer of edible materials which can apply and form on the surface of the products, maybe an alternate method to minimize changes in Physalis during storage (Licodiedoff et al. - This study aims to determine the physical characteristics of AV gel film as well as the effect of AV gel as an edible coating or film on minimizing the changes in physicochemical properties of Physalis fruits during cold storage and its role in enhancing the postharvest quality and shelf life of Physalis.. - The other ingredients used to prepare an AV gel film and coating [Corn starch with 12% moisture content], as a thickening agent and glycerol (98%)]. - The AV gel was prepared as described by Elbandy et al. - (2014), then the AV gel was filtered for removing the fibers. - After that, the pH of the AV gel was adjusted by using citric acid solution (4.5g l -1 ) to pH (4) as recommended by Adetnji et al. - Finally, to obtain the volume in 400 ml, the AV gel (with moisture content 98.92 The calyx removing of Physalis peruviana fruits for production of fresh cut fruit makes its shelf life shorter. - AV gel film was effective in controlling the fungal decay. - This study showed that the AV gel could be suitable for producing an edible film and coating with good physical characteristics such as low WVP (0.0037g/m 2 .h.mmHg). - Evaluation of the film characteristics. - Five measurements were done for each film sample and expressed as µm (Abd El Magied et al. - The water solubility % was determined as the average value of 3 measurements as follows (Sadegh et al. - The third treatment: coating of Physalis fruits with AV coating by dipping into the AV gel solution at 25◦C for 1 min.. - The decay was observed and determined visually as recommended by Shehata et al. - The weight loss percentage was calculated by the difference between the initial weight of fruits and the weight of fruits at and 30 d multiplied by 100 (Awad et al. - Fruits firmness was determined using a texture analyzer as described by Licodiedoff et al. - The fruit's color was measured using a colorimeter with a Minolta standard (KONICA MINOLTA, Japan) according to the method described by Ganjloo et al., (2009). - browning index (BI) for the mean of 3 determinations for each treatment according to the method described by Palou et al., (1999).. - Fruit’s pH measured using the digital pH meter (Hanna Instruments, HI 9219) according to Ali et al. - Then 10 ml of the aliquot was taken and titrated with 0.1 N NaOH in present of Phenolphthalein as an indicator in triplicates, from the titer, the Titrable acidity % was calculated (El – Mogy et al. - The maturity index was calculated according to Catarina et al. - The obtained results are in accordance with Ortega-Toro et al. - Also, Pinzon et al. - (2018) was shown that the thickness of starch–chitosan– Aloe vera gel film was increased 59.3 to 174.5 𝜇m with increasing of AV gel concentration 0 to 500 g/l.. - Abugoch et al. - Also, Silva-Weiss et al. - The obtained results were shown that the water solubility (WS) of AV gel was relatively low (20.65. - These can be observed by Sadegh et al. - (2012) who noticed that an increment in the portion of AV gel was followed by a decreasing in the water solubility of Aloe vera gel incorporated into Chitosan films. - A similar effect was also shown when Pinzon et al. - (2018) added AV gel into the chitosan film at 50%. - Even though it is important to know that the most components of the AV gel are polysaccharides, organic acids and amino acids, which have highwater solubility, so they could easily soluble from the edible films. - So, the lower water solubility of AV gel film or how the addition of AV to different types of edible polymers decreasing water solubility still unknown and need more study.. - The water vapor permeability of AV gel film at 30 ° C and 0/100 % relative humidity was recorded as 0.0037 g.m -2 .h.mmHg, which is considered relatively low in comparison with other polysaccharides polymer films. - So, the AV gel addition could be used for reducing WVP with other types of polysaccharide polymer film as shown in the study of Sadegh et al. - (2012) who found that AV gel incorporation had the potential role in enhancing the chitosan film barrier property to water vapor. - Ortega-Toro et al.. - (2018) reported that, the addition of AV gel significantly decreases the water vapor permeability values of the banana starch–chitosan films 2.85 g Pa −1 s −1 m −1 in films without AV gel to 1.99 g Pa −1 s −1 m −1 . - Also, he explained that, with the interaction between the AV gel components and starch-chitosan molecules, reducing the availability of the hydrophilic groups in all of starch and chitosan to interact with water and reducing the film's WVP.. - These results are in accordance with Licodiedoff et al. - This result is similar to the result of Tripathi et al. - (2004), who reported that AV gel was successful in reducing microorganism proliferation in table grape, the effect is higher for yeast and molds than for mesophillic aerobics. - Moreover, Brishti et al. - (2014) reported that decay percentage reached 27% of papaya fruits coated with AV gel compared with the control which reached to 100% at the end of storage. - Also, Ortega-Toro et al. - (2017) showed that, the starch-based film containing AV gel (1:1 w/w) was more effective for controlling fungal decay in cherry tomatoes because he found that, the AV gel has a good effect as antifungal especially for Fusarium oxysporum. - That was explained by Cock, (2008) who identified 26 bioactive phytochemical compounds in AV gel such as anthraquinones, dihydroxyanthraquinones, saponins, acemannan.. - A similar effect was reported by Mohebbi et al. - Morillon et al. - of physalis fruits (Table 1). - A similar effect was observed by Bolzan et al. - Also, Mohebbi et al. - The coating may also inhibit the activities of pectin-degrading enzymes closely related to decrease in texture by reducing the metabolic processes rate during senescence, which also participated in the maintenance of fruit hardness (Gwanpua et al. - Usage of AV gel blend coating or film enhance the protection of physalis fruits which could lower the change of TSS% which recorded 12.10%. - The obtained results are in accordance with Sharmin et al. - (2015), who found that, the lowest TSS% 7.610% was found in papaya coated with AV gel (1.5. - This may be due to the effect of AV gel coating on the lowering the activity of α-galactosidase, polygalacturonase and pectin methylesterase (Nunan et al.. - 0.05).The AV gel (film or coating) could delay the increase in BI during storage which reached to 126.11 and 131.03, respectively compared with the control which reached to 207.72 at the end of storage. - These results are in accordance with Supapvanich et al. - (2016) who reported that, the ability of fresh AV gel for maintaining L * and delaying the increase in browning index of apple slices after storage for 6 days at 4°C.. - According to previous articles , AV gel edible coating was shown a reduction in firmness loss, moisture loss, respiratory rate, development in maturity, delay browning index, and microorganism growth in fruits such as table grapes (Martinez-Romero et al. - 2006) and nectarines (Ahmed et al. - 2009) also, they suggested that the AV gel coating or film created a modified atmosphere around the fruits which reduced the production rate of ethylene, which, delay ripening, degradation of chlorophyll, accumulation of anthocyanin and synthesis of carotenoid and that lower fruits color surface changes.. - Also, Sharmin et al. - (2015), reported that papaya fruits coated AV gel (0.5%) recorded the minimum change of titrable acidity (0.39. - This retention of TA content by coated papaya was due to the protective effect of AV coating as a barrier to O 2 from the surrounding atmosphere and reduction of respiration (Srinu et al. - Andrea et al. - The obtained results in accordance with Athmaselvi et al.. - (2013) showed that the pH value of uncoated tomato after 20 days of storage was 4.15, whereas for tomato fruits coated with AV gel was 4.07. - The respiration process of fruits corresponds to the oxidation reactions of organic acids and carbohydrates which are converted to water and CO 2 , and producing chemical energy during storage Athmaselvi et al. - Maturity index showed significant change during cold storage between control and other treatments meanwhile, no differences were observed between film and coating of AV gel (Fig 4). - These results are in according with Catarina et al. - The results showed the ability of AV gel coat or film for significantly decreasing the metabolism activity of fruit during the storage at 5°C without significant changes of the fruit organoleptic quality.. - The coated fruits, as well as the fruits packed into the AV gel film, were superior compare to the control sample for color, taste, texture and overall acceptability up to 12 days of storage period that affected by the surrounded environmental conditions.. - These results in accordance with Martinez-Romero et al. - (2006) who reported that the cherry tomato coated with AV gel and stored for 16 days at 1°C had a good appearance and acceptable flavor than the control which, showed several symptoms of dehydration and color oxidation.. - The results of this study showed that the AV gel solution is suitable for producing an edible film and coating with good physical characteristics. - https://doi.org/10.1016/j.foodhyd . - J., Singh, Z., and Khan, A.S. - https://doi.org/10.1111/j x. - https://doi.org . - https://doi.org/10.3390/foods10051103. - https://doi.org/10.1021/jf050962v. - https://doi.org/10.5580/15bc. - https://doi.org/10.1016/j.postharvbio . - and et al., (2014). - https://doi.org/10.17660/actahortic . - https://doi.org/10.1111/j tb09857.x. - https://doi.org/10.1016/j.carbpol . - Journal of the Bangladesh Agricultural University
Xem thử không khả dụng, vui lòng xem tại trang nguồn hoặc xem
Tóm tắt