Food Technology
Hoda Ghorbanzadeh; Jafar Milani; Ali Motamedzadegan
Abstract
IntroductionWith the growth of the population and more demand for obtaining food and supplying the required food, the interest in the cultivation and consumption of edible mushrooms has increased. Since 1990, the world has focused on the mushroom production industry. In recent years, mushrooms have become ...
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IntroductionWith the growth of the population and more demand for obtaining food and supplying the required food, the interest in the cultivation and consumption of edible mushrooms has increased. Since 1990, the world has focused on the mushroom production industry. In recent years, mushrooms have become one of the most important food and medicinal sources. One of the largest species of edible mushroom is button mushroom (Agaricus bisporus), which has high nutritional and medicinal value. Button mushroom has high nutritional value due to the presence of things such as fiber, carbohydrates, protein, amino acids, minerals, vitamins, etc., and it also has antioxidant, anti-cancer, and anti-diabetic properties. This food has shown good health properties for humans. The quality of button mushrooms is determined by their color, texture, and taste. Color is the first characteristic that is perceived by consumers. Browning is one of the main reasons for the loss of mushroom quality, which reduces the commercial value of mushrooms. One of the most used methods today is the use of edible coatings for perishable foods, these coatings almost prevent the penetration of oxygen, depending on the type of coating used, and reduce the loss of moisture during storage. Chitosan has functional characteristics such as antimicrobial and antioxidant properties, and as an edible film, it can be considered a very good carrier to be combined with antioxidant and antimicrobial agents.Materials and methodsTo make chitosan solutions, first, each type of chitosan (70% deacetylated, 80% deacetylated, 90% deacetylated, and 100% deacetylated) was weighed in amounts of 0.5g, 1g, and 2g. then it was dissolved in 100 ml of 0.5% acetic acid solution and stirred for 12 hours at a speed of 1000 rpm at room temperature to dissolve uniformly. After 12 hours, each sample It was centrifuged for 15 minutes at 6000 rpm at 25 °C to separate the undissolved material. Mushrooms were prepared freshly harvested, washed with water, and then excess moisture was removed. After sorting and screening in terms of size and approximate weight, the mushrooms were added to 0.5%, 1%, and 2% chitosan solutions without being sliced and were immersed in the solution for one minute. The control sample was immersed in 0.5% acetic acid solution for one minute. After that, the mushrooms were air-dried at room temperature for one hour, and at the end, their excess moisture was removed with a tissue. The mushrooms were placed in 18*14 size polyethylene zip-top bags and stored in a refrigerator at 4°C. The effects of chitosan coating on weight loss, mushroom color and browning index, enzyme activity, texture, and total phenolic compounds were studied.Results and discussionThe results indicated that in maintaining the amount of total phenol, controlling the peroxidase enzyme activity, the degree of firmness of the mushroom during storage and the amount of gumminess, the best treatment was chitosan with a deacetylation degree of 70%, while in controlling the weight loss, the activity of poly Phenol oxidase and sensory test, chitosan treatment with 100% and 90% deacetylation degree had better results, and in terms of browning index and texture, chitosan treatment with 80% deacetylation degree showed better performance. This study showed that the use of chitosan coating can be effective in maintaining the characteristics of edible mushrooms.ConclusionsThe spoilage of edible mushrooms happens in a short time, and the storage of mushrooms has become one of the most important things in mushroom production. Coating edible mushrooms is one of the suitable methods to increase the shelf life of edible mushrooms. In this research, chitosan with four degrees of deacetylation and three different concentrations was used as a coating for edible mushrooms. The results indicated that coating the mushroom with chitosan could delay the occurrence of spoilage and change its color or texture.
Mahyar Rad; Hamed Ghafori; Zohreh Gholami
Abstract
Introduction: Edible mushrooms are among the most perishable products that begin to lose quality immediately after harvest, and the short shelf-life of these products will cause problems when it comes to the marketing and distribution of these products in a fresh form. Edible coatings are a good tool ...
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Introduction: Edible mushrooms are among the most perishable products that begin to lose quality immediately after harvest, and the short shelf-life of these products will cause problems when it comes to the marketing and distribution of these products in a fresh form. Edible coatings are a good tool for prolonging the useful life of foods and increasing their quality without contaminating the environment. Materials and Methods: In this study, the possibility of increasing the shelf-life of a button mushroom using blanching followed by coating with carboxymethyl cellulose and sodium metabisulfite was studied. Independent variables included concentrations of carboxymethyl cellulose and sodium metabisulfite (0-2%) and storage time up to 16 days at 4 ° C. This experiment was designed on the basis of three-level factors consisting of 6 central points after 0, 4, 8 and 16 days of storage at 4°C. Factors determined on a button mushrooms included pH measurements, weight loss percentage, soluble solids, texture, color, browning level, total microorganisms count as well as mold and yeast count. Results & Discussion: The results of this study indicated that the sample coated with 2% carboxymethyl cellulose and 2% sodium metabisulfite resulted in an increase in pH level as well as soluble solids. In addition, the slightest color change, weight loss and reduction in tissue stiffness were observed in this sample. The sample coated with 2% carboxymethyl cellulose with 2% sodium metabisulfite had also the lowest total microorganisms count and the count of mold and yeast stored at 4 ° C after 16 days. Based on the results of this study, carboxymethyl cellulose and sodium metabisulfite coatings can be used as an appropriate coating agents for the preservation of organoleptic, chemical, microbial properties and shelf-life of button mushrooms.
