Poiana Mariana-Atena, Alexa Ersilia, Mateescu Constantin
Banat's University of Agricultural Sciences and Veterinary Medicine, Faculty of Food Processing Technology, Calea Aradului 119, RO 300645, Timisoara, Romania.
Chem Cent J. 2012 Jan 16;6:4. doi: 10.1186/1752-153X-6-4.
Recently, an increased interest in the identification of valuable possibilities for preserving the antioxidant properties of products obtained by thermal processing of fruits rich in bioactive compounds can be noticed. In this regard, an extensive analysis is necessary in terms of thermal processed products behavior in relation to various factors. The purpose of the present study was to assess the effect which processing and storage at 20°C has on the antioxidant properties and color quality of low-sugar bilberry jam with different low-methoxyl pectin (LMP) concentrations.
For all measured parameters, it should be noted that thermal processing induced significant alterations reported to the values registered for fresh fruit. Most important losses due to thermal processing were recorded for total monomeric anthocyanins (TMA) (81-84%), followed by L-ascorbic acid (L-AsAc) content (53-58%), total phenolics (TP) content (42-51%) and FRAP (ferric reducing antioxidant power) values (36-47%). Moreover, depreciation of the investigated compounds occurred during storage at 20°C. Jam storage for 7 months resulted in severe losses in TMA content in the range 58-72% from the value recorded one day after processing. This coincided with marked increases in polymeric color percent of these products after 7 months of storage. Also, bilberry jam storage for 7 months resulted in a decrease in L-AsAc content of 40-53% from the value recorded one day after processing, 41-57% in TP content and 33-46% from the value recorded one day after processing for FRAP values. By decreasing of LMP concentration in the jam recipe from 1 to 0.3% there has been an increase in losses of investigated compounds.
Overall, the results indicated that bilberry jams can also represent a good source of antioxidant compounds, although compared to the fruit, important losses seem to occur. Practical application of this work is that this kind of information will be very useful in optimizing the jam processing technology and storage conditions, in order to improve the quality of these products.
最近，可以注意到人们越来越关注确定通过对富含生物活性化合物的水果进行热加工所获得产品的抗氧化性能的宝贵保留可能性。在这方面，有必要就热加工产品与各种因素相关的行为进行广泛分析。本研究的目的是评估在20°C下加工和储存对不同低甲氧基果胶（LMP）浓度的低糖越橘果酱的抗氧化性能和颜色质量的影响。
对于所有测量参数，应注意热加工导致与新鲜水果记录值相比有显著变化。热加工导致的最重要损失是总单体花青素（TMA）（81 - 84%），其次是L - 抗坏血酸（L - AsAc）含量（53 - 58%）、总酚（TP）含量（42 - 51%）和FRAP（铁还原抗氧化能力）值（36 - 47%）。此外，在20°C储存期间，所研究的化合物发生了降解。果酱储存7个月导致TMA含量从加工后一天记录的值严重损失58 - 72%。这与这些产品在储存7个月后聚合物颜色百分比的显著增加相吻合。同样，越橘果酱储存7个月导致L - AsAc含量从加工后一天记录的值下降40 - 53%，TP含量下降41 - 57%，FRAP值从加工后一天记录的值下降33 - 46%。通过将果酱配方中LMP浓度从1%降至0.3%，所研究化合物的损失有所增加。
总体而言，结果表明越橘果酱虽然与水果相比似乎会发生重要损失，但仍可代表抗氧化化合物的良好来源。这项工作的实际应用是，此类信息对于优化果酱加工技术和储存条件以提高这些产品的质量将非常有用。
