Food Biotechnology
Dina Shahrampour; Morteza Khomeiri; Seyed Mohammad Ali Razavi; Mahboobeh Kashiri
Abstract
Introduction: Due to the low variety of probiotic food products, it is important to provide appropriate solutions for new products. Trapping probiotic bacteria in the polymers structure of edible films and coatings is a new approach that has been proposed to increase the survival of these microorganisms ...
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Introduction: Due to the low variety of probiotic food products, it is important to provide appropriate solutions for new products. Trapping probiotic bacteria in the polymers structure of edible films and coatings is a new approach that has been proposed to increase the survival of these microorganisms and to develop new probiotic products in the food industry.Materials and Methods: In this study, an alginate-based probiotic bioactive film containing L. plantarum was fabricated. The effect of bacterial addition on physical, mechanical and prevention properties of alginate film was evaluated. In addition, the effect of two temperatures 4 ° C and 25 ° C on the survival of embedded probiotic bacterium in the film structure during one month of storage was investigated by microbial count assay on MRS agar medium. Then, the model food was covered with probiotic film and the survival of probiotic bacterium during food storage was determined.Results and Discussion: The results showed that the population decline of probiotic bacterium after drying of alginate film solution was about 4.61%. Addition of probiotic bacterium to the alginate film increased the thickness, turbidity, and tensile strength of the film, While on solubility, water activity, Elongation(%) and microstructure of alginate film had no significant effect. In addition, the probiotic film containing bacteria had less luminosity, moisture content and water vapor permeability (WVP) than the control film. The survival percentage of L. plantarum in alginate film after one month of storage at 4 ° C was higher than 25 ° C and 96.84 and 47.29%, respectively. Also, the population of embedded bacteria in the film structure on the food model (sausage) surface after three weeks storage in refrigeration was in desired level of probiotic products (> 106 cfu / gr).Conclusion: Therefore, alginate film is recommended as a suitable carrier for probiotic microorganisms to produce new functional products.
Roya Rezaei; Hadi Koohsari
Abstract
Probiotics are living microorganisms that provide beneficial effects when they are eaten with food. The probiotic dairy products raise the risks associated with increased cholesterol and lactose intolerance. In this research, fruit and vegetable juices of apple, banana, carrot and tomato were used as ...
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Probiotics are living microorganisms that provide beneficial effects when they are eaten with food. The probiotic dairy products raise the risks associated with increased cholesterol and lactose intolerance. In this research, fruit and vegetable juices of apple, banana, carrot and tomato were used as substrates for producing probiotic beverages and the viability of two LABs of L. acidophilus and L. plantarum in these products was investigated. Fruit and vegetable juices were inoculated with bacterial suspensions to obtain a concentration of 105 CFU/ml for each LAB. Samples were incubated at 37°C for 72 hours and at 24-hour intervals, pH levels and viable cell count in products were determined based on CFU/ml. Fermented products were transferred to the refrigerator and the viability of LABs was determined at 4°C for 4 weeks. The results show that, in all products, the pH decreased over time, so that there was a significant difference between the two examined bacteria during the experiment (P<0.05). Both LABs were able to grow well in products and to ferment the fruit and vegetable juices properly implying that all the beverages were able to provide suitable conditions for the growth of two strains of LABs. L. plantarum showed a higher viability in cold storage at 4°C. In general, considering the high growth rate of these bacteria in the products and pH reduction and their viability during cold storage at 4°C, fruit and vegetable juices of apple, banana, carrot and tomato can be a good substrate for producing non-dairy probiotic beverages.
