Effect of alcoholic fermentation on the quality of grape brandies

Abstract

Grape brandy is a product obtained by fermentation and distillation of crushed grapes of cultivated grapevine Vitis vinifera. Grape brandy quality depends on many factors such as: grapevine varieties, climate, soil, time and method of distillation, storage methods and other distillates. The grapevine variety 'Neoplanta' grown in the experimental field of the PD 'Center for Viticulture and Enology' in Niš was used in the experiment. Tests were performed in the laboratory of the Centre. Healthy grapes of harvest maturity were squashed by a stalk-removing electric crusher. Fermentation was performed in plastic containers in the presence of the indigenous microflora of wine yeasts. This paper presents the influence of pH and inorganic nitrogen added to the fermentation medium on the content of volatile components and concentrations of higher alcohols.

Lozovača ili lozova rakija predstavlja proizvod koji se dobija fermentacijom i destilacijom celog kljuka grožđa plemenite vinove loze Vitis vinifera. Kvalitet rakije lozovače zavisi od velikog broja faktora: sorte vinove loze, klime, zemljišta, vremena i načina destilacije, načina čuvanja destilata i dr. Za realizaciju ovog eksperimenta korišćeno je grožđe sorte vinove loze 'Neoplanta' koja se gaji na oglednom imanju PD 'Centar za vinogradarstvo i vinarstvo' u Nišu. Ispitivanja su izvedena u laboratorijskim uslovima Centra. Zdravo i tehnološki zrelo grožđe je izmuljano električnom muljačom koja odvaja peteljke. Fermentacija celokupnog kljuka grožđa je izvršena u plastičnim vrionim posudama u prisustvu autohtone mikroflore vinskih kvasaca. U radu je prikazan uticaj pH vrednosti i neorganskog azota dodatog u fermentacionu smešu na sadržaj isparljivih komponenti i koncentraciju viših alkohola.