Changes in hop (Humulus lupulus L.) oil content and composition during long-term storage under different conditions

Rutnik, Ksenija (author), Ocvirk, Miha (author), Košir, Iztok Jože (author)

Hop essential oil, in addition to alpha-acids, is one of the most valuable parameters for brewers, since it is responsible for beer aroma. The hop oil content and hop oil chemical composition deliver various aromas to beer. During storage, the hop chemical composition undergoes many physical and chemical changes that impact its quality. The main purpose of our study was to evaluate the changes occurring in hop oil content and its chemical composition during two years of storage under four different conditions (anaerobic, aerobic, cold room (4 °C), and room temperature) in the form of cones and pellets, supplied by local suppliers in Slovenia. Hop oil content and composition were determined by steam distillation and GC-FID. The greatest decrease in hop essential oil content occurred when the hops were stored under aerobic conditions and at room temperature. Monitoring of eight hop oil compounds under various conditions revealed different behaviors of the changes. The best storage conditions were anaerobic at low temperatures. Oxygen resistance was lower for pellets than for hop cones, whereas high temperature was more devastating for hop cones. In addition to the storage conditions, the hop variety and form were important factors regulating the extent of changes in hop oil content and chemical composition.

• Language: English
• Keywords: hops, storage stability, essential oils, hop oil composition
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2022
• Number of pages: 20 str.
• Numbering: Vol. 11, iss. 19, art. 3089
• PID: 20.500.12556/RUL-155484
• UDC: 633.791
• ISSN on article: 2304-8158
• DOI: 10.3390/foods11193089
• COBISS.SI-ID: 128588291
• Publication date in RUL: 04.04.2024

Record is a part of a journal

• Title: Foods
• Shortened title: Foods
• Publisher: MDPI
• ISSN: 2304-8158
• COBISS.SI-ID: 512252472

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: hmelj, skladiščenje, eterična olja, sestava

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: 603-1/2019-15

• Funder: ARRS - Slovenian Research Agency
• Project number: Z4-2655
• Name: Proučevanje vplivov staranja hmelja na lastnosti piva