The effect of process conditions on the physical, chemical, volatile organic compounds and rheological properties of apricot sauces produced from Malatya apricots

In the present study, during the processing of apricots to pulp and sauce, change in physical, chemical, volatile organic compounds and rheological properties of the products were investigated. In the first part, mash, heated mash, pulp and skin were obtained from several process steps. Processing of apricot to pulp resulted in statistically important change of pH, dry matter content and brix values (P˂0.05); however, variation of titratable acidity was found as not significant (P˃0.05). Total carotenoid, phenolic contents and antioxidant activity decreased with processing (P˂0.05). Sitric acid was found as the dominant organic acid in all samples. Ascorbic acid content decreased in a ratio of 64.47 %. Totally 38 different volatile organic compounds were detected and processing markedly changed the volatile composition. In the second part of the study, apricot pulp and sauce were produced with processes where different blanching temperatures (85°C-95°C), times (5-10 min) and sieve diameters (1-3 mm) were performed. Prepared pulps and sauces were stored at +4°C for 2 months and the analyses were conducted at 0, 15, 30, 45, and 60. days of storage. Blanching temperature and time, sieve diameter and storage period significantly affected the physical and chemical properties of the pulp and sauce (P˂0.05). Increasing of blanching temperature, blanching time and storage period decreased loss (G") and storage modulus (G') and they increased with rising of sieve diameters. Herschel-Bulkley was found as the most approprite model describing the flow behaviour of the samples with R2 values higher than 0.97. 43 and 49 of volatile organic compounds were detected in pulps and sauces, respectively and the process conditions significantly influenced the volatile composition.