Department of Biological Systems Engineering, Washington State University, Pullman, WA 99164-6120, USA.
J Sci Food Agric. 2010 Apr 15;90(5):769-78. doi: 10.1002/jsfa.3882.
Consumer demand for organic foods is increasing despite a lack of conclusive evidence of nutritional superiority of organically grown produce. The objective of this investigation was to evaluate the effects of thermal treatments on phytochemicals in conventionally and organically grown berries. Two cultivars of conventionally and organically grown red raspberries and blueberries were analysed for total anthocyanins, total and specific phenolic compounds and total antioxidant activity. Fresh berries were thermally processed into cans and juice/puree with and without blanching, and the changes in phytochemicals were monitored.
Total anthocyanin and phenolic contents of berries were not influenced by the agricultural production system. Total antioxidant activity of berries was also not influenced by the production system, but antioxidant activity varied significantly between cultivars. After canning, total anthocyanins decreased by up to 44%, while phenolic contents and antioxidant activity of both berries generally increased by up to 50 and 53% respectively. The level of changes in phytochemicals during berry puree/juice processing was influenced by blanching and type of berries.
Phenolic contents and antioxidant activities of berries increased while total anthocyanins decreased during canning. Blanching prior to puree/juice processing improved the retention of phytochemicals in blueberries.
尽管没有确凿的证据表明有机种植的农产品在营养上具有优势，但消费者对有机食品的需求仍在不断增加。本研究的目的是评估热处理对传统和有机种植浆果中植物化学物质的影响。对两种传统和有机种植的红树莓和蓝莓品种的总花青素、总酚和特定酚类化合物以及总抗氧化活性进行了分析。新鲜浆果经过热加工成罐头和果汁/果泥，有和没有烫漂，并监测植物化学物质的变化。
浆果的总花青素和酚类含量不受农业生产系统的影响。浆果的总抗氧化活性也不受生产系统的影响，但不同品种之间的抗氧化活性差异显著。罐装后，总花青素含量下降了多达 44%，而酚类含量和两种浆果的抗氧化活性分别增加了多达 50%和 53%。在浆果泥/汁加工过程中，植物化学物质的变化水平受到烫漂和浆果类型的影响。
在罐装过程中，浆果的总花青素含量下降，而酚类含量和抗氧化活性增加。在进行果汁/果泥加工之前进行烫漂可以提高蓝莓中植物化学物质的保留率。
