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  • Author or Editor: John W. Finley x
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Juice production is a multibillion dollar industry and an economical way to use fruit past seasonal harvests. To evaluate how production steps influence not-from-concentrate (NFC) blueberry (Vaccinium sp.) juice recovery, bench top and pilot scale experiments were performed. In bench-top, southern highbush (SHB) blueberry (Vaccinium darrowii × Vaccinium corymbosum) and rabbiteye blueberry (RAB) (Vaccinium ashei) were pressed at varying temperatures. Press treatments included ambient temperature, frozen then thawed, and frozen then heated berries. In addition, two commercial pectinase enzymes were evaluated. Three batches were pressed and average juice recovery was calculated. The highest average free juice recovery (68.8% ± 1.1%) was attained by heating frozen berries and treating with enzyme. Comparing berry species pressed, SHB blueberries produced significantly more juice than RABs. There were no significant differences between enzymes used between berry species. Using this preliminary data, the optimum juice recovery method was then transferred to pilot scale processing. RABs were heated and treated with enzyme then pressed. Free juice recovery from the pilot scale was 74.0% ± 1.0%. Total juice recovery was calculated to be 87% ± 0.6%. With this information, further refinement of juice processes could increase juice production output for small-scale producers and expand local outlets for growers to market their crops as well as create new opportunities for growth in the fresh juice market segment.

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Broccoli(Brassica oleracea L. Italica Group) can contain high levels of selenium (Se) in the form of selenium methyl selenocystine. This is a relatively unique Se compound that is found in certain plant species that accumulate this element. Several recent studies have shown that high Se broccoli can inhibit the development of certain cancers (e.g., colon and mammary) in rodents and this has led to increasing interest in broccoli as a vegetable that confers chemoprotective effects. The objective of this research was to determine the relative importance of genotype vs. environment in the expression of Se concentration in broccoli heads. A set of 15 broccoli inbreds and a set of 20 hybrids were evaluated in three different environments. Mature heads were harvested from plots, heads were dried and ground, and Se concentration was determined on a dry weight basis. Overall, Se levels measured in this study were low to moderate, typically ranging from about 20 to more than 100 ng/gdw of Se per head. For both inbreds and hybrids, the effect of environment on Se head concentration was highly significant and more than 10 times greater than the effect of genotype. When analyzed across all three environments, the genotypic effect on Se concentration was significant for hybrids only. However, when assessed for individual environments, the genotypic effect was significant in just one of three of the test environments with both inbreds and hybrids. Results indicate that genetic modification of broccoli to increase selenium concentration of heads will likely be difficult to achieve.

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