Polak Natalia, Kalisz Stanisław, Hać-Szymańczuk Elżbieta, Kruszewski Bartosz
Department of Food Technology and Assessment, Institute of Food Sciences, Warsaw University of Life Sciences-SGGW, 02-776 Warsaw, Poland.
Department of Biotechnology and Food Microbiology, Institute of Food Sciences, Warsaw University of Life Sciences-SGGW, 02-776 Warsaw, Poland.
Foods. 2024 Dec 8;13(23):3963. doi: 10.3390/foods13233963.
Berries are a valuable source of numerous bioactive compounds, and they have an interesting organoleptic profile. Unfortunately, their low storage life determines the need for their preservation. Among the various methods used in this regard, it was decided to use the High Temperature Short Time (HTST) (90 °C/15 s) and Ultra-High Temperature (UHT) (130 °C/5 s) methods to preserve the produced fruit nectar blends (strawberry-blackcurrant and strawberry-chokeberry). For comparison, the nectars were also preserved using conventional pasteurization (90 °C/10 min). Physicochemical, chromatographic, and microbiological determinations were carried out in the tested nectars before and immediately after processing, as well as after 1, 2, 3, 4, and 6 months of refrigerated storage. All methods allowed for the significant inactivation of selected microbial groups. Non-significant changes were observed as a result of HTST and UHT processing in the context of pH, TSS, and titratable acidity. Varied major changes occurred in the content of bioactive components (TPC-decrease or increase by 2-4%, TAC-decrease by 3-20%, vitamin C-decrease by 15-78%), antioxidant activity (decrease or increase by 3-9%), and nephelometric turbidity (decrease or increase by 11-65%). Both nectars showed better quality and nutritional value after the HTST and UHT processes compared to treatment with classic pasteurization. Storage affected the degradation of bioactive compounds, reduced antioxidant activity, increased turbidity, and caused the brightening of samples together with reducing redness and yellowness. Considering the results obtained, it is reasonable to recommend the use of the HTST and UHT methods in industrial conditions for the preservation of liquid fruit and vegetable products such as juices, nectars, and beverages.
浆果是多种生物活性化合物的宝贵来源，且具有有趣的感官特性。不幸的是，它们的储存期较短，因此需要进行保存。在这方面所使用的各种方法中，决定采用高温瞬时（HTST）（90℃/15秒）和超高温（UHT）（130℃/5秒）方法来保存所生产的水果花蜜混合物（草莓 - 黑加仑和草莓 - 醋栗）。作为对比，花蜜也采用传统巴氏杀菌法（90℃/10分钟）进行保存。在加工前、加工后即刻以及冷藏储存1、2、3、4和6个月后，对测试的花蜜进行了物理化学、色谱和微生物学测定。所有方法都能使选定的微生物群体显著失活。在pH值、总可溶性固形物（TSS）和可滴定酸度方面，HTST和UHT处理后未观察到显著变化。生物活性成分的含量（总酚含量 - 降低或增加2 - 4%，总花青素含量 - 降低3 - 20%，维生素C - 降低15 - 78%）、抗氧化活性（降低或增加3 - 9%）和比浊法浊度（降低或增加11 - 65%）发生了不同程度的主要变化。与传统巴氏杀菌处理相比，HTST和UHT处理后的两种花蜜均表现出更好的品质和营养价值。储存会影响生物活性化合物的降解、降低抗氧化活性、增加浊度，并导致样品变亮同时降低红色度和黄色度。考虑到所获得的结果，推荐在工业条件下使用HTST和UHT方法来保存液体水果和蔬菜产品，如果汁、花蜜和饮料是合理的。
