Traditional pear cultivars are increasingly in demand by consumers because of their excellent taste, the possibility of use in sustainable food production systems, convenience as raw materials for obtaining products of high nutritional quality, and perceived health benefits. In this study, individual sugars, organic acids, and polyphenols in the fruits of nine traditional and one commercial pear cultivar during two growing seasons were determined by HPLC. A significant influence of cultivars, growing years, and their interaction on the content of analyzed primary and secondary metabolites was determined. The commercial pear cultivar ‘Président Drouard’ and traditional cultivars ‘Dolokrahan’, ‘Budaljača’, and ‘Krakača’ had a lower content of all analyzed sugars. Overall, traditional pear cultivars had higher total polyphenols in the peel and pulp than ‘Président Drouard’, with the exception ‘Takiša’ and ‘Ahmetova’. High polyphenol content detected in ‘Budaljača’, ‘Dolokrahan’, and ‘Krakača’ shows the utilization value of traditional pear germplasm. The obtained data can serve as practical supporting data for the use of traditional pears in the neutraceutical, pharmaceutical, and food industries.

The self-rooted plum genotype ‘Mrkosljiva’ was first selected as it was devoid of Sharka leaf symptoms during the 5‑year study (2009–2014), which was subsequently confirmed by negative ELISA test results. Hence, the aim of the study was to investigate the biochemical variability of the autochthonous ‘Mrkosljiva’ plum genotype, based on its sugar, acid and phenolic compounds content during 3 years. In 2010 and 2011, the plums tasted sweet with favourable sugar:acid ratios of 55:1 to 65:1. These plum fruits were collected at the full ripeness stage from an extensive orchard located in northeastern Bosnia and Herzegovina (45 °N). Analysis by HPLC identified the following polyphenolic compounds—chlorogenic acid, cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside, neochlorogenic acid, quercetin-3-O-galactoside and quercetin-3-O-rutinoside—in all 3 years that were evaluated (2009–2011), but in different amounts, depending on the environmental conditions of each year. In 2009, the plums were healthier with a threefold greater phenol content than during the other 2 years of growth. In 2009, protocatechuic acid was detected, whereas catechin, procyanidin B1, procyanidin B2 and quercetin-3‑O-rhamnoside were not detected. The combination of high phenol and sugar content in ‘Mrkosljiva’ provides healthy and tasty plums suitable primarily for processing, and to a lesser extent, due to their size, for fresh fruit marketing.

Three commercial apple cultivars ('Jonagold', 'Granny Smith' and 'Idared') and the local apple cultivar ('Prijedorska Zelenika') from Bosnia and Herzegovina were analysed by HPLC-MS for the content of phenolic compounds in peel and pulp as well content of individual sugars and organic acids. Catechin, (-)-epicatechin, chlorogenic acid, caffeic acid, quercetin 3-O-xyloside, quercetin 3-O-arabinoside, quercetin 3-O-rhamnoside, quercetin 3-O-rutinoside, quercetin 3-O-galactoside and quercetin 3-O-glucoside were identified in apple peel and (-)-epicatechin, chlorogenic acid and caffeic acid in apple pulp at all observed cultivars. The total sugars content of analysed apple cultivars ranged between 91.61 and 105.45 g kg-1 FM, while the total organic acids content was from 5.70 to 15.05 g kg-1 FM. The levels of total organic acids and sugars, glucoce/fructose ratio and sugar/acid ratio were affected by cultivars. The mean content of total phenolic compounds was between 427.92 and 1457.95 mg kg-1 FM in peel and from 113.58 to 439.83 mg kg-1 FM in pulp and depending upon the cultivars. The presented data clearly demonstrated that traditional apple cultivar ('Prijedorska Zelenika') had significantly higher individual phenolic compounds in pulp in comparison to the commercial cultivars, i.e., 'Idared', 'Jonagold' and 'Granny Smith' and with respect of that 'Prijedorska Zelenika' is recommended as raw material for cloudy juice processing.

The main purpose of this study was to evaluate the effect of calcium fertilizer treatments on fruit quality and distribution of calcium in apple fruit (Malus domestica Borkh. cv. Idared). Four treatments were tested: application of calcium nitrate through the fertigation system, foliar application of calcium nitrate, application of calcium oxide through soil, and control treatment (without calcium fertilizer). In the experiment, freshly picked apples harvested in Gorazde region (eastern Bosnia) in September 2018 were analyzed. The highest impact to increase calcium content in apple had a treatment where calcium nitrate was added through the fertigation system. It was the result of the balance between calcium and nitrogen in the applied solution as well as the fertigation capacity to timely deliver nutrition to the main rooting zone. Calcium distribution was not uniform within the fruit: the highest content was found in the apple core, decreasing in the apple flesh, and rising again in the apple skin, regardless of fertilizer treatment. There was no difference among calcium fertilizer treatments in total soluble solids and titratable acidity of apple, indicating that these treatments were insufficient in order to improve the examined parameters of fruit quality.