Connor Ann Marie, Luby James J, Hancock James F, Berkheimer Steven, Hanson Eric J
Department of Horticultural Science, University of Minnesota, 1970 Folwell Avenue, St. Paul, Minnesota 55108, USA.
J Agric Food Chem. 2002 Feb 13;50(4):893-8. doi: 10.1021/jf011212y.
Antioxidant activity, total phenolic content, anthocyanin content, and six other fruit characters including titratable acid concentration, soluble solids, firmness, and percentage of bruised berries were determined for nine blueberry (Vaccinium L. sp.) cultivars at harvest and at various postharvest intervals after storage at 5 degrees C. Berries from MSU-58, Brigitta, and Legacy stored successfully for 7 weeks, Bluegold stored for 3-5 weeks, Bluecrop, Elliott, and Nelson stored for 3 weeks, and Jersey and Little Giant stored for fewer than 3 weeks. During the time they retained marketable quality, one cultivar (MSU-58) demonstrated a 29% increase in antioxidant activity. None of the cultivars showed a significant decrease from the harvest antioxidant activity value during storage. Antioxidant activity, total phenolic content, and anthocyanin content were strongly correlated with each other (r = 0.87-0.99, P < 0.01). All three parameters were moderately correlated with soluble solids (r = 0.47, P < or =0.05; r = 0.44, P < or = 0.05; and r = 0.64, P < or = 0.01, respectively), and antioxidant activity and total phenolic content were both moderately correlated with pH (r = 0.53 and 0.49, respectively; P < or = 0.05). However, antioxidant activity, total phenolic content, and anthocyanin content showed no correlation with firmness, percent severely bruised berries, or weight loss. Antioxidant activity and total phenolic content at harvest both correlated with titratable acidity at harvest (r = 0.68, P < or = 0.05 and r = 0.70, P < or = 0.05, respectively) on a cultivar mean basis. Berries from Elliott were also harvested from plants at two levels of bush ripeness (30-50% and 60-80% ripe berries on plants) and separated into three fruit maturity classes on the basis of percent blue color. The level of bush ripeness had no significant effect on antioxidant activity, total phenolic content, or anthocyanin content; however, fruit maturity had a significant effect on antioxidant activity, total phenolic content, and anthocyanin content, and bush ripeness x fruit maturity interactions were significant for these three traits. Berries with 50-75% blue coloration harvested from bushes with 60-80% mature fruit showed a significant increase in antioxidant activity, total phenolic content, and anthocyanin content during the first 3 weeks in storage. Our results demonstrate that increases in antioxidant activity, total phenolic content, and anthocyanin content may occur in the blueberry during cold storage and are cultivar-dependent. The increases that occur in immature fruit, such as in Elliott, may be advantageous for producers who wish to delay marketing of the fruit.
测定了9个蓝莓（越橘属）品种在收获时以及在5℃储存后的不同采后期的抗氧化活性、总酚含量、花青素含量，以及其他6个果实特性，包括可滴定酸浓度、可溶性固形物、硬度和碰伤浆果的百分比。来自MSU - 58、布里吉塔和遗产品种的浆果成功储存了7周，蓝金品种储存了3 - 5周，蓝丰、埃利奥特和尼尔森品种储存了3周，而泽西和小巨人品种储存时间少于3周。在保持适销品质的期间，一个品种（MSU - 58）的抗氧化活性提高了29%。在储存期间，没有一个品种的抗氧化活性值比收获时显著降低。抗氧化活性、总酚含量和花青素含量之间高度相关（r = 0.87 - 0.99，P < 0.01）。所有这三个参数与可溶性固形物呈中度相关（分别为r = 0.47，P ≤ 0.05；r = 0.44，P ≤ 0.05；r = 0.64，P ≤ 0.01），抗氧化活性和总酚含量与pH值均呈中度相关（分别为r = 0.53和0.49；P ≤ 0.05）。然而，抗氧化活性、总酚含量和花青素含量与硬度、严重碰伤浆果百分比或重量损失均无相关性。在品种平均值基础上，收获时的抗氧化活性和总酚含量均与收获时的可滴定酸度相关（分别为r = 0.68，P ≤ 0.05和r = 0.70，P ≤ 0.05）。埃利奥特品种的浆果还从处于两个灌木成熟度水平（植株上30 - 50%和60 - 80%成熟浆果）的植株上收获，并根据蓝色百分比分为三个果实成熟等级。灌木成熟度水平对抗氧化活性、总酚含量或花青素含量没有显著影响；然而，果实成熟度对抗氧化活性、总酚含量和花青素含量有显著影响，并且灌木成熟度×果实成熟度的相互作用对这三个性状有显著影响。从60 - 80%成熟果实的灌木上收获的蓝色占50 - 75%的浆果在储存的前3周内抗氧化活性、总酚含量和花青素含量显著增加。我们的结果表明，蓝莓在冷藏期间抗氧化活性、总酚含量和花青素含量可能会增加，并且这取决于品种。未成熟果实（如埃利奥特品种）中出现的增加可能对希望延迟果实上市的生产者有利。
