The Change of Total Anthocyanins in Blueberries and Their Antioxidant Effect After Drying and Freezing

Abstract

This study examined the effects of freezing, storage, and cabinet drying on the anthocyanin content and antioxidant activity of blueberries (Vaccinium corymbosum L). Fresh samples were stored for two weeks at 5°C while frozen samples were kept for up to three months at −20°C. There were two drying treatments, one including osmotic pretreatment followed by cabinet drying and the other involving only cabinet drying. Total anthocyanins found in fresh blueberries were 7.2 ± 0.5 mg/g dry matter, expressed as cyanidin 3-rutinoside equivalents. In comparison with fresh samples, total anthocyanins in untreated and pretreated dried blueberries were significantly reduced to 4.3 ± 0.1 mg/g solid content, 41% loss, and 3.7 ± 0.2 mg/g solid content, 49% loss, respectively. Osmotic treatment followed by a thermal treatment had a greater effect on anthocyanin loss than the thermal treatment alone. In contrast, the frozen samples did not show any significant decrease in anthocyanin level during three months of storage. Measurement of the antioxidant activity of anthocyanin extracts from blueberries showed there was no significant difference between fresh, dried, and frozen blueberries.

Effect of Pre-Treatments on Quality Attributes of Solar Dehydrated Grape Pomace

“…Anthocyanins leakage might happen due to dewaxing, which was caused by soaking during the pretreatment. This observation is comparable to the study by (Lohachoompol et al, 2004) who found that dewaxing weakened the berry cuticle and allowed the skin to rupture. This permitted some leakage from the exposed edges or undersurface of the torn skin to the pretreated solution that caused anthocyanins loss before the drying process.…”

Stability of Haskap Berry (Lonicera Caerulea L.) Anthocyanins at Different Storage and Processing Conditions

“…juice extraction and subsequently sold as a dried berry product. Despite the varied functions and health benefits of ANCs, they are very labile and undergo significant breakage and structural changes during storage and processing (Ochoa et al, 1999;Lohachoompol et al, 2004;Sadilova et al, 2006). Due to their highly reactive nature, ANCs readily degrade to colorless or brown compounds.…”

Evaluation of the in vivo mutagenic potential of hydroalcoholic extracts of the northern highbush blueberry (Vaccinium corymbosum L. Ericales, Ericaceae) on peripheral blood cells of Swiss mice (Mus musculus Rodentia, Muridae)

“…In related work we have attempted to quantify the total phenolics and anthocyanins in V. corymbosum simple hydroethanolic extract and found that the total concentration of phenolic compounds, expressed as catequin equivalents) 5.66 ± 0.01 mg g -1 , while the anthocyanin content was 0.099 ± 0.05 mg g -1 for cyanidin, 0.063 ± 0.06 mg g -1 for delphinidin and 0.131 ± 0.06 mg g -1 for malvidin (Torri et al, 2007, in press). Despite the proven antioxidant effect of these anthocyanins (Lohachoompol et al, 2004) and the fact that several phenolic compounds have also shown antimutagenic properties (Matkowski and Wolniak, 2005;Ragunathan and Panneerselvam, 2007) the mutagenic potential of some phenolic compounds is well known (Huberman et al, 1976;Snyder and Hedli, 1996). Although further investigations will be necessary, is possible that some phenolic compounds present in V. corymbosum extract could be responsible for the clastogenic or aneugenic effect observed by us with the MN assay.…”

“…In recent decades interest in the anthocyanin content of some Vaccinium species has revived due to the pharmacological properties of anthocyanins, which includes antioxidant activity (Wang et al, 1997;Mazza et al, 2002;Lohachoompol et al, 2004), anti-inflammatory effects (Youdim et al, 2002), cardiovascular protection, antidiabetic properties, improvements to vision and inhibition of carcinogenesis (Cabrita and Andersen, 1999;Camire, 2000;Katsube et al, 2003). The fruits of the economically important northern highbush blueberry (Vaccinium corymbosum L.) are consumed in many countries throughout the world because they contain large amounts of antioxidants thought to be beneficial to health (Prior et al, 1998;Ehlenfeldt and Prior, 2001).…”