Vpliv postopkov shranjevanja na vsebnosti izbranih primarnih in sekundarnih metabolitov v plodovih nešplje (Mespilus germanica L.)

Jakljevič, Katja (author), Mikulič Petkovšek, Maja (mentor)

Nešplja (Mespilus germanica L.) ali mušmula spada v družino rožnic (Rosaceae) in izvira iz jugozahodne Azije. Poznamo več sort nešpelj, in sicer 'Domača' ali 'Navadna' nešplja, 'Kraljevska' ali 'Royal', 'Holandska' in 'Nottingham' nešplja. Plodovi so značilne temno rjave barve z veliko muho. Tehnološko zreli plodovi niso užitni, zato jih po obiranju shranimo v temnem in hladnem prostoru, da se umedijo ali pa jih pustimo na drevesu, da so izpostavljeni slani. Plodovi nešplje so bogat vir primarnih in sekundarnih metabolitov, ki imajo koristne in zdravilne učinke na zdravje ljudi. V magistrski nalogi smo preučevali vpliv različnih načinov shranjevanja na vsebnost izbranih primarnih in sekundarnih metabolitov v plodovih nešplje. Ugotovili smo, da plodovi nešplje vsebujejo največ fruktoze (59,2 g/kg sveže mase (FW)) in glukoze (54,4 g/kg FW), med organskimi kislinami pa jabolčne (8,4 g/kg FW) in kinske kisline (8,8 g/kg FW). Izmed fenolov predstavljajo največje vsebnosti predstavljajo fenolne kisline (532,85 mg/kg FW) in flavanoli (375,21 mg/kg FW). Ugotovili smo, da se s shranjevanjem nešpelj zmanjšuje vsebnost vseh primarnih in sekundarnih metabolitov. Umedene nešplje, ki so skladiščene v kleti, imajo značilno najmanjše vsebnosti vseh analiziranih metabolitov. Ugotavljamo, da je zaradi precej velike vsebnosti metabolitov v plodovih nabranih po slani, to najprimernejši način shranjevanja za nešpljo. Takrat so plodovi užitno zreli in hkrati vsebujejo velike vsebnosti fenolnih snovi.

• Language: Slovenian
• Keywords: Mespilus germanica, nešplja, primarni metaboliti, sekundarni metaboliti, sladkorji, organske kisline, fenolne spojine
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [K. Jakljevič]
• Year: 2021
• PID: 20.500.12556/RUL-133460
• UDC: 634.15:631.563:543.6(043.2)
• COBISS.SI-ID: 87236867
• Publication date in RUL: 28.11.2021

Secondary language

• Language: English
• Title: The impact of storage procedures on the content of determined primary and secondary metabolites in medlar fruits (Mespilus germanica L.)

Abstract

Medlar (Mespilus germanica L.) belongs to Rosaceae family and is indigenous to southwest Asia. There are several cultivars of common medlar plant: ‘Domača’ or ‘Navadna’, 'Royal', 'Hollandia' and 'Nottingham'. The fruits are typically dark brown with a big calyx. Technologically ripe fruits are not edible, therefore they need to be stored in a dark and cold place after harvesting in order to undergo bletting. Alternatively, they can be left on a tree to soften and become bletted by frost. The medlar fruits are rich in primary and secondary metabolites, both of which have beneficial and healing health effects. In this master thesis the influence of different ways of storage procedures on the content of selected primary and secondary metabolites in medlar fruits were studied. The major determined sugars in fruits were fructose (59.2 g/kg fresh weight (FW)) and glucose (54.4 g/kg FW), whereas malic acid (8.4 g/kg FW) and quinic acid (8.8 g/kg FW) were major acids in medlar. Among the phenolics phenolic acids (532.85 mg/kg FW) and flavanols (375.21 mg/kg FW) were major groups. It was determined that storage reduces the content of all primary and secondary metabolites. Bletted medlars which were stored in a cellar had the lowest content of all metabolites. It was established that the most appropriate method of storage is harvesting fruit after natural hoarfrost. The fruits are at that time edibly ripe and at the same time possess high contents of metabolites.

• Keywords: Mespilus germanica, medlar, primary metabolites, secundary metabolites, sugars, organic acids, phenols