A dedicated team of horticultural scientists from Edith Cowan University (ECU) in Australia is making significant strides in the effort to use melatonin in efforts to keep fruits and vegetables fresh for longer periods of time.
For the past year, they have been gathering and examining global research to evaluate the potential benefits of applying melatonin, a hormone naturally occurring in living organisms, to fresh produce.
The team’s leader, Professor Zora Singh, disclosed that a staggering 44 percent of fresh horticultural produce is wasted from farm to consumption. This loss is largely attributable to a phenomenon known as ‘chilling injury’.
“You will often see abnormal ripening, sunken spots, pitting, hardening of flesh and browning of peel and pulp in cold-stored fruits, while browning of tissues, translucency and water-soaked lesions in the vegetables, that is what we call chilling injury,” he explained.
Storage conditions play a critical role in the occurrence of chilling injury. Shippers store subtropical fruits and vegetables at average temperatures between 4–8°C. Tropical produce, however, requires a slightly warmer 10–20°C to sidestep this issue.
As the researchers delved into this area, the mounting evidence pointed to melatonin as a promising candidate for mitigating the effects of chilling injury in cold-stored produce.
Shoaib Shah, a PhD student and researcher on Professor Singh’s team, noted that melatonin, also known as a sleep-inducing hormone in living creatures, is beneficial in reducing chilling injury symptoms and membrane leakage. It works by maintaining higher antioxidant levels, thereby keeping horticultural produce fresher.
Shah also emphasized the safety of melatonin application, labeling it a “safe alternative to hazardous chemical treatments, without any adverse effects on consumer health.”
The stakes are high in this melatonin research. Food security continues to be a growing concern around the world, with food losses escalating each year.
Annually, we lose a shocking 13.2 percent of food, equivalent to a $400 billion value, between harvest and the retail market. This, according to a 2019 report by the Food and Agriculture Organization (FAO).
Furthermore, the United Nations Environment Programme (UNEP) revealed in 2020 that 17 percent of food production is wasted at the household, food service, and retail levels. This food loss and waste account for approximately 8-10 percent of global greenhouse gas emissions.
Professor Singh’s work is even more critical when considering the steady decline in fruit production. Various factors link to this decrease. These include diminishing agricultural land, dwindling water supplies, climate change, and soil degradation.
Chilling injury is another culprit. It causes 44 percent of fruits and vegetables to be unfit for human consumption worldwide.
Tropical and sub-tropical fruits, due to their high perishability, are particularly vulnerable. For example, we can store apples for up to nine months, but we can only keep berries refrigerated for seven to 12 days.
Speaking about the resilience of produce, Professor Singh compared grains and other harvested goods to fresh horticultural produce. He pointed out that fruits and vegetables pose more challenges, both in terms of growth and preservation. Singh declared this issue a global crisis, stressing the need for sustainable solutions.
“Fruit and vegetables are not only challenging to grow, preserving them is immensely difficult and this is a crisis affecting nations all over the world, so we need to find the solution to keep producing food from the earth in a sustainable way,” he said.
Professor Singh, along with his research team, is working diligently to counter global food and nutritional security challenges. Their focus is on enhancing production technology and curbing postharvest losses in fresh horticultural produce, from farm to fork. Melatonin may be an unlikely savior.
The pineal gland in the brain primarily produces melatonin, a hormone naturally occurring within the body. Its primary function is to regulate sleep-wake cycles, or circadian rhythms, making it a critical component of the body’s internal clock.
Light exposure closely ties to the production and release of melatonin. When darkness falls, the pineal gland responds by synthesizing melatonin from the amino acid tryptophan. This occurs through a process that also involves the neurotransmitter serotonin.
The elevated levels of melatonin in the bloodstream signal the body that it is time to sleep. Conversely, during daylight hours, the production of melatonin decreases. This change helps to maintain alertness and wakefulness.
Beyond its role in sleep regulation, melatonin serves other functions in the body. It acts as an antioxidant, helping to protect cells from damage by free radicals. Research suggests that melatonin might enhance the immune system, support eye health, and have potential anti-cancer properties.
Melatonin also helps in regulating body temperature, blood pressure, and hormone levels. Its role in sleep regulation is beneficial for various physiological processes such as memory consolidation and tissue repair, which primarily occur during sleep.
Due to its role in promoting sleep, synthetic melatonin is available as an over-the-counter supplement in many countries. It is often used to treat insomnia and other sleep disorders, combat jet lag, and help shift workers adjust to new sleep schedules.
However, while melatonin supplements are generally safe for short-term use, they can cause side effects like headaches, dizziness, and daytime sleepiness. Long-term effects of melatonin supplement use are still being studied.
In addition to humans, many animals produce melatonin, and it plays a crucial role in their seasonal breeding, hibernation, and migration patterns. Plants also produce melatonin, where it functions as an antioxidant and helps to regulate growth.
Ongoing research is investigating melatonin’s potential benefits for various health conditions such as heart disease, Alzheimer’s, and cancer. Studies are also assessing the hormone’s potential effects on mental health disorders like depression and anxiety. However, more clinical trials are needed to fully understand these potential uses and their implications for treatment.
In summary, melatonin is a hormone with significant roles in sleep regulation and other physiological functions. It continues to be the subject of extensive research due to its potential health benefits and use as a treatment for various conditions. As with all substances, it should be used responsibly, and under the guidance of a healthcare professional.