The aim of the graduation thesis was to investigate the chemical composition of chokeberry (Aronia mitschurinii) juice produced from fruits of different maturity stage. We investigated how the fruit maturity and the corresponding chemical composition affects the sensory properties of the juice. Chokeberry fruits variety 'Galacjanka' were harvested in three different periods of maturity and were made to juice. The soluble solids of juice from first to last maturity stage amounted to 19.81 ± 0,1 °Brix, 21.23 ± 0,2 °Brix and 25.37 ± 0,3 °Brix respectively. The antioxidant potential (AOP) of juice was measured with DPPH? method and results were expressed as ascorbic acid (AK) equivalents. Juice AOP from first to last maturity stage were 7673,20 ± 98,7 mg AK / L, 8471,9 ± 30,0 mg AK / L and 9987,58 ± 79,2 mg AK / L. Sensory analysis were carried out with non-trained evaluators, results are expressed with liking degree on a 9-point hedon scale. Evaluators scored as the best juice from fruits from second maturity stage, they descriptevily expressed as 'like slightly'. The juice from first harvest was rated 'dislike slightly', while the third sample was rated with 'neither like nor dislike'. Evaluators also sorted juices according to the intensity of sweetness and astringency. The juice from first harvest was rated as the most astrigent, juice from the second harvest as the least astringent. The perceived sweetness was the lowest in juice from the first harvest and higest in juice from the third harvest. The highest yield of the extracted juice was obtained from the fruits from the second harvest. Results showed that juice from the second harvest had suitable chemical composition and was sensorially evaluated as the best.
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