Recent developments in colorimetric and optical indicators stimulated by volatile base nitrogen to monitor seafood freshness

• Published in: Food packaging and shelf life 2021-06, Vol.28, p.100634, Article 100634
• Main Authors: Ma, Qianyun, Lu, Xiaomin, Wang, Wenxiu, Hubbe, Martin A., Liu, Yaqiong, Mu, Jianlou, Wang, Jie, Sun, Jianfeng, Rojas, Orlando J.
• Format: Article
• Language: English
• Subjects: Colorimetric sensor; Freshness; Nano technology; Seafood; Volatile base nitrogen
• ISSN: 2214-2894; 2214-2894
• DOI: 10.1016/j.fpsl.2021.100634

[Display omitted] •Recent optically colorimetric indicators detecting seafood freshness were reviewed.•Innovations in macromolecular and forms of freshness indicators were enriched.•Nano technology was effective in improving efficacy of indicators.•Current challenges and developments of freshness indicators were also put forward. Seafood spoilage could cause food waste and also serious foodborne disease because of the specific organisms and their metabolites. Therefore, it is important to monitor their freshness in the supply chain. In most cases, their spoilage has been determined by the content of volatile base nitrogen, adenosine triphosphate or the total viable count. However, these destructive detection methods are tedious and time consuming. Hence, it is highly desirable to develop easily operated and non-destructive sensing technologies for real-time detection. A lot of freshness indicators have emerged up to now. Colorimetric indicators are particularly beneficial to accompany use-by dates in food packaging as real-time indicators because they produce visible color changes to the naked eye, which can be easily understood by consumers and non-specialists. Numerous studies have considered the colorimetric indicators to monitor seafood freshness in recent years. This paper mainly focused on colorimetric indicators stimulated by volatile base nitrogen. The most traditional materials used in these indicators are also discussed. The challenges and opportunities in the systems are introduced in this context as well based on the published literature.