# Different Temperature Storage Conditions and Packaging Types Affects Colour Parameters, Amino Acid Composition, Microbial Contamination, and Key Bioactive Molecules of Moringa oleifera Lam. Powder

## TL;DR

This study shows that storing Moringa oleifera leaf powder at cooler temperatures and in the dark preserves its color, nutrients, and bioactive compounds better than higher temperatures and light exposure.

## Contribution

The study identifies optimal storage conditions (4°C in dark) for preserving Moringa oleifera's bioactive compounds and minimizing microbial growth.

## Key findings

- Lower temperatures (4°C) preserved higher levels of quercetin-3-rutinoside, rutin, and chlorogenic acid compared to higher temperatures.
- Light exposure and higher temperatures increased microbial contamination and accelerated degradation of phytochemicals.
- Color changes were most pronounced at higher temperatures, especially under light exposure.

## Abstract

Moringa oleifera, renowned for its medicinal potency, was investigated to discern the impact of varying storage temperatures (4 °C, 25 °C, 40 °C) and light conditions (dark and light) on the quality attributes of its leaf powder during a 12-month storage period. The study encompassed comprehensive analyses of phytochemical levels, nutritional properties, microbial contamination, and colour changes in response to these diverse storage environments. The lightness L* colour value changed significantly (40 to 60) from baseline tests when stored at 40 °C in transparent packaging. Results highlighted distinct variations in phytochemical composition and nutritional content based on the interplay between temperature and light conditions. Lower temperatures, particularly 4 °C, in both dark and light environments, demonstrated superior preservation of bioactive compounds, with mean values for quercetin-3-rutinoside of 3.34 µg/g and 3.19 µg/g, respectively; both are significantly higher compared to other treatments (p < 0.05). This trend was also observed for rutin, chlorogenic acid, and quercetin. Conversely, higher temperatures (25 °C, 40 °C) coupled with light exposure hastened degradation, notably impacting phytochemical stability. Microbial proliferation was evident in elevated temperatures, indicating potential safety risks. Further observations unveiled significant colour changes within the leaf powder, notably influenced by storage temperatures and light exposure. Lower temperatures exhibited diminished colour alterations compared to higher temperatures, underscoring their impact on product quality. This study underscores the critical role of controlled storage conditions, especially cooler temperatures and reduced light exposure, in maintaining the potency and quality of M. oleifera leaf powder. Recommendations advocate for stringent temperature control (preferably 4 °C) and light shielding during storage to uphold phytochemical stability and mitigate microbial proliferation. While this study provides valuable insights into temperature-mediated alterations, future research avenues should delve deeper into elucidating the underlying mechanisms of colour changes and long-term temperature effects on phytochemical and nutritional integrity.