Effects of carvacrol wash and ally isothiocyanate vapor treatment to extend the shelf life of blackberries

Authors: YU, YUANSHAN - Guangdong Academy Of Agricultural Sciences; Jin, Zhonglin; Fan, Xuetong; Gurtler, Joshua

Submitted to: Jacobs Journal of Food and Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/17/2019
Publication Date: 7/29/2019
Citation: Yu, Y., Jin, Z.T., Fan, X., Gurtler, J. 2019. Effects of carvacrol wash and ally isothiocyanate vapor treatment to extend the shelf life of blackberries. Jacobs Journal of Food and Nutrition. 6(4):46-57.

Interpretive Summary: Contaminations with spoilage and pathogenic microorganisms may reduce the shelf life of fresh blackberries and cause a food safety concern. This study investigated the methods to reduce microbial contaminants by means of an essential oil wash, essential oil vapor or by their combination. The results suggest that the combination of essential oil washing and essential oil vapor treatment is not necessary. Essential oil vapor treatment alone appears to be very promising for maintaining the microbiological and nutritional qualities and extending the shelf-life of blackberries.

Technical Abstract: Blackberries are a nutritious fruit with a short shelf-life due to the presence of spoilage microorganisms. There is also a potential for contamination with pathogenic microorganisms as has occurred with other berries. In this study, two essential oils (EOs) were used to treat fresh blackberries for the extension of shelf-life. The application methods of EOs on blackberries included: (1) washing with a carvacrol (COL) solution, (2) treatment with ally isothiocyanate (AIT) vapor, and (3) COL washing followed by AIT vapor treatment. The survival of total bacterial populations, yeast and mold populations, and changes in respiration rate, quality and nutrient contents were determined during a12 d storage study at 10 deg C. The washing treatment reduced microbial loads by 2 log CFU/g initially but did not inhibit their outgrowth during storage, while AIT vapor treatment and the combination of COL wash and AIT vapor treatment both completely inhibited the growth of bacteria and mold and yeast. AIT vapor alone or in combination with COL wash significantly reduced the respiration rate of blackberries, hence, maintaining the quality and nutritional values through 12 d of storage. The results suggest that the combination of COL washing and AIT vapor is not necessary and AIT vapor treatment alone appears to be very promising for extending the shelf-life of blackberries.