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Sweet corn is frequently consumed in the US and contains carbohydrates as major macronutrients. This study examined the effects of blanching, freezing, and canning on carbohydrates in sweet corn. Fresh bi-color sweet corn was picked in the field and processed immediately into frozen and canned samples. Simple sugars, starch, and dietary fiber (DF) (including total DF (TDF), insoluble DF (IDF) and two fractions of soluble DF (SDF)) were measured according to the AOAC methods. Additional glycomic analysis including oligosaccharides, monosaccharide composition of total polysaccharides (MCTP) and glycosidic linkage of total polysaccharides (GLTP) were analyzed using UHPLC-MS. Sucrose is the major simple sugar, and IDF is the main contributor to TDF. Sucrose and total simple sugar concentrations were not altered after blanching or freezing but were significantly reduced in canned samples. Kestose was the only oligosaccharide identified in sweet corn and decreased in all heat-treated or frozen samples. Starch content decreased in frozen samples but increased in canned samples. While two SDF fractions did not differ across all samples, blanching, freezing and canning resulted in increases in TDF and IDF. Six monosaccharides were identified as major building blocks of the total polysaccharides from MCTP analysis. Glucose and total monosaccharide concentrations increased in two canned samples. GLTP was also profoundly altered by different food processing methods. This study provided insights into the changes in the content and quality of carbohydrates in sweet corn after food processing. The data are important for accurate assessment of the carbohydrate intake from different sweet corn products.

Soybeans have diverse uses in foods and are known for their health-beneficial properties. Research has shown that consumption of soybeans or their components may help to prevent or alleviate chronic illnesses including heart disease, some cancers, and osteoporosis. Foods made from soybeans can develop flavors or odors that are unfavorable, in part because of lipid oxidation. Approaches to prevent lipid oxidation include modification of soybean traits such as fatty acid composition or lipoxygenase enzyme levels. Soybeans with modified α–linolenic acid (18:3n3) and soybeans with reduced lipoxygenase were analyzed to determine if there was an unintentional effect of modification on health-beneficial components. The effects of genotype and growing environment on nutraceutical components were analyzed for the modified 18:3n3 soybeans. Additionally, an assay for measurement of lipoxygenase–1content in soybean meal was developed for high-throughput analysis using fluorescein as a fluorescent probe. The results showed a significant effect of genotype of at least p ≤ 0.05 for fatty acid composition, isoflavone levels, lutein, and tocopherol levels in the modified 18:3n3 soybeans. Environment had significant effect on certain fatty acids, lutein, tocopherols, and oxygen radical absorbance capacity (ORAC). The effect of genotype × environment was significant for total phenolic content (TPC) and antioxidant activity against hydroxyl radical, as well as isoflavone composition, fatty acid composition, lutein, and tocopherol composition. Soybean lines with modified-lipoxygenase content contained similar or higher isoflavone levels compared to non–modified soybeans. The results of this research demonstrated that soybean modifications for improved oil stability did not adversely affect the health-enhancing components. Additionally, genotype or growing environment may be a factor in selecting the best soybean lines for nutraceutical d

Eight soybean genotypes grown in Maryland were analyzed for total phenolic content (TPC), antioxidant capacity, isoflavone composition, lutein content, tocopherol composition, and fatty acid profile. The soybean samples consisted of seven low alpha-linolenic (18:3n-3) experimental lines and one standard cultivar for comparison. 18:3n-3 levels were negatively correlated with oleic acid (18:1n-9). The isoflavones daidzein and genistein were positively correlated with 18:3n-3 levels. Alpha-tocopherol, gamma-tocopherol, and total tocopherols were negatively correlated with 18:3n-3. Two of the reduced 18:3n-3 lines contained significantly higher lutein levels than the ordinary cultivar. All low alpha-linolenic lines contained similar antioxidant capacity to the non-modified genotype. The results of this study show that the Maryland-grown low 18:3n-3 soybeans are sources of antioxidants and isoflavones and may be consumed for health benefits. Specific genotypes may be selected for food production to obtain the most desirable combination of nutritional, nutraceutical, and chemical properties.