Volatile compounds and odour characteristics during long-term storage of kombu seaweed (Laminaria ochroleuca) preserved by high pressure processing, freezing and salting

Publication date: January 2020Source: LWT, Volume 118Author(s): Olga López-Pérez, Ana del Olmo, Antonia Picon, Manuel NuñezAbstractKombu seaweed (Laminaria ochroleuca) was preserved by refrigeration at 5 °C (control), by high pressure processing (HPP) at 400 or 600 MPa for 5 min followed by refrigeration at 5 °C, or by freezing at −24 °C. Those treatments were applied to both unsalted and salted kombu samples, which were stored for 180 days. One hundred three compounds belonging to 16 chemical groups were identified in the volatile fraction of kombu. Groups including the highest number of volatile compounds were alcohols (24), aldehydes (13), ketones (10), alkanes (9), haloalkanes (9), alkenes (8) and acids (7). HPP lowered the levels of acids, aldehydes, ketones, lactones + ionones, pyranones and terpenes + terpenoids, and increased alkenes and furans. Freezing lowered the levels of alkanes, aromatic hydrocarbons, pyranones and terpenes + terpenoids, and increased aldehydes, haloalkanes and thiazoles. Salting lowered the levels of pyranones, and increased acids, alcohols, aldehydes, alkanes, aromatic hydrocarbons, furans, haloalkanes, lactones + ionones and thiazoles. Control kombu odour acceptance fell below rejection level on day 60 while HPP-treated kombu showed the highest odour acceptance until day 180. Frozen kombu exhibited abnormal odours whereas salted kombu maintained acceptable odour characteristics. Principal component analysis associated the...
Source: LWT Food Science and Technology - Category: Food Science Source Type: research