Naslov
Specialized metabolites profile of strawberry fruit during flash-freezing.
(Specialized metabolites profile of strawberry fruit during flash-freezing)

Autori
Šić Žlabur, Jana ; Duralija, Boris ; Emanović, Zrinka ; Mikulec, Nataša ; Voća, Sandra

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
9th international strawberry symposium-Growing strawberry from the Equator to the Arctic / Mezzetti, Bruno - Rimini, 2021, 173-173

Skup
IX International Strawberry Symposium

Mjesto i datum
Rimini, Italija, 01.05.2021. - 05.05.2021

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Fragaria × ananassa Duch. ; freezing, bioactive compounds ; storage ; antioxidant capacity

Sažetak
Strawberry fruit species given the extremely high water content (90-92%) are prone to the rapid spoilage and therefore it is difficult to preserve it fruits for the longer time period. One of the effective method to preserve strawberry fruits with significant preservation of nutritional and sensory quality is freezing. Conventional freezing methods imply longer time period (usually 24 h) and temperatures around -18 °C whereby larger ice crystals grow thus damaging cell structures impacting on the degradation of physico-chemical as well bioactive compounds content. Alternative method to conventional freezing is flash-freezing which implies significantly lower freezing temperatures (cryogenic) allowing freezing for just few minutes. The aim of this study was to evaluate the effect of freezing method (conventional, flash-freezing) on the content of predominant specialized metabolites of strawberry fruit. Also, to determine the preservation of nutritional quality of frozen strawberry fruit during storage period of 10, 20 and 30 days. Fresh strawberry fruits cv. ‘Sophia’ were purchased from the family farm producer and prepared for freezing, petiole and fruits with mechanical and visible signs of spoilage were removed. Conventional freezing was conducted at -18 °C for 24 h in classic freezer, while flash freezing at -34° C for 25 min in shock freezer (Tecnomac Sf 1, Italy). Specialized metabolites content was analysed for fresh samples (S1), immediately after defrosting for flash-frozen (Sff0), classical frozen (Sc0) and both for flash and classical frozen after storage period of 10 days (Sff10 and Sc10), 20 days (Sff20 and Sc20) and 30 days (Sff30 and Sc30). According to the obtained results significantly higher values of vitamin C (5 times), total phenolic compounds (2 times), non- flavonoids (1.5 times), flavonoids (50 %), total anthocyanins (3 times) and antioxidant capacity (2.7 %) were determined in strawberry fruits frozen by flash-freezing compared to the conventional method. Also, as expected regardless of the freezing method, content of all analysed specialized metabolites significantly decreased during storage period. It should be emphasized that during storage however nutritional quality of flash-frozen samples were better preserved compared to the samples frozen by conventional method. Based on the stated, it can be concluded that flash-freezing significantly preserved content of all analysed specialized metabolites in strawberry fruit thus can be recommended as effective method for strawberry processing.

Izvorni jezik
Engleski

Znanstvena područja
Poljoprivreda (agronomija), Prehrambena tehnologija

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