Impact of light quality on leafy green vegetables

Fruits and vegetables are a vital part of the human diet, and their consumption is on the rise because they are considered as a healthy intake. However, ingredients of fruits and vegetables are vulnerable in postharvest handling like moisture loss, wrong handling, physical damage, and microbial c...

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Detalles Bibliográficos
Autor principal: Abdul Aziz, Muhammad
Formato: Second cycle, A2E
Lenguaje:sueco
Inglés
Publicado: 2022
Materias:
Acceso en línea:https://stud.epsilon.slu.se/17607/
Descripción
Sumario:Fruits and vegetables are a vital part of the human diet, and their consumption is on the rise because they are considered as a healthy intake. However, ingredients of fruits and vegetables are vulnerable in postharvest handling like moisture loss, wrong handling, physical damage, and microbial contamination. Postharvest moisture loss in fruits and vegetables affects weight, texture, appearance, acridness, vitamins, sugar and phenolic. Outbreaks of food borne related illnesses have been increasing during the last two decades. Many of the diseases have been associated with leafy green vegetables contaminated with human pathogens such as shiga toxin producing Escherichia coli O157:H7. To eradicate the pathogens from the surfaces of vegetables and fruits in postharvest handling, chlorine-based sanitizers treatments are widely used. But there are some complications of using chlorine-based sanitizers for example, producing harmful compounds like chloroform and its residual toxicity supposed to have negative repercussions on human health. Therefore, researchers are looking for alternative safe and less expensive methods for sanitization, one of which is the use of blue light. In the field of microbiology recent studies showed the potential of influencing the behavior of E. coli O157:H7 by using a certain wavelength of light within the visible spectrum can help to kill the bacterial pathogens with a positive effect on maintaining quality. The main purpose of this study is to investigate the effect of blue light dose on spinach baby leaves in terms of freshness and weight retention during shelf life. To conduct this study, spinach leaves were exposed to blue light with a wavelength of approximately 460 nm for 0, 2, 4, 6 and 8 hours intervals. The weight and leaf firmness were measured after each time interval. In the control samples, the same methodology was applied on spinach leaves without being exposed to blue light dose. The results have shown no significant effect on spinach leaves weight and hardness under blue light dose exposure. However, a significant loss in weight was observed when spinach leaves were not exposed to blue light. This study has shown that there is a possibility of using blue light as a disinfectant, but more research is needed to optimize the dose and exposure duration of blue light so that the product itself is not damaged in terms of quality and freshness taking into account various factors such as growing conditions, logistics and storage climate conditions etc. The combined effect of blue light with other light spectrums such as green and red could be a future action point.