Effects of different treatments on the volatile compounds, heavy metals, minerals, amino acids and bioactive compounds of the edible brown alga Spatoglossum asperum
摘要
Seaweeds have gained increasing attention in recent years as a potential food source due to their diverse nutritional composition and health benefits. The potential use of seaweed for human consumption is accompanied by several challenges, primarily due to their strong fishy odor and bioaccumulation of heavy metals, which are the main factors limiting their acceptability. Additionally, issues such as limited availability, high price, and the lack of large-scale commercial cultivation further hinder widespread adoption. This study focused on the use of novel non thermal treatments—cold plasma activated water (PAW) with an activation time of 15 min, ultraviolet radiation (UV) for 30 min and thermal treatments—microwave (MW) blanching at 600 W for 120 s, to address the existing challenges. These technologies offer versatile applications in food processing, including microbial inactivation, heavy metal reduction, and preservation of the nutritional and sensory quality of food, while also promoting sustainability through reduced processing time and energy consumption. All of the treatments (PAW, UV and MW) were effective in decreasing the fishy smell and heavy metal content in the edible brown seaweed Spatoglossum asperum. Aldehydes (hexanal and (E)-2-octenal) were identified as the main compounds responsible for the fishy odor by GC‒MS/MS. However, the use of microwave blanching at 600W for 120 s resulted in better odour removal (hexanal by 58% and (E)-2-octenal by 26%) and a reduction in the total heavy metal content by 33% (from 141 µg kg−1 in the control to 95 µg kg−1 in the treated samples). The microwave treatments also significantly (p < 0.05) impacted nutritional composition and bioactive compounds. These microwave treatments could facilitate the use of seaweed as a primary component in food without significantly compromising its nutritional value, palatability or odor. Additionally, the technique offers potential sustainability benefits, such as faster processing time, reduced water and energy consumption making it a more cost-effective and environmentally friendly processing method.