Effect of the Drying Method and Storage Conditions on the Quality and Content of Selected Bioactive Compounds of Green Legume Vegetables

This study aimed to determine the effect of the drying method (freeze-drying, air-drying), storage period (12 months), and storage conditions (2-4 °C, 18-22 °C) applied to two legume species: green beans and green peas. The raw and dried materials were determined for selected physical parameters typical of dried vegetables, contents of bioactive components (vitamin C and E, total chlorophyll, total carotenoids, β-carotene, and total polyphenols), antioxidative activity against the DPPH radical, and sensory attributes (overall quality and profiles of color, texture, and palatability). Green beans had a significantly higher content of bioactive components compared to peas. Freeze-drying and cold storage conditions facilitated better retention of these compounds, i.e., by 9-39% and 3-11%, respectively. After 12 months of storage, higher retention of bioactive components, except for total chlorophyll, was determined in peas regardless of the drying method, i.e., by 38-75% in the freeze-dried product and 30-77% in the air-dried product, compared to the raw material.

Curly Kale (Brassica oleracea var. Sabellica L.) Biofortified with 5,7-Diiodo-8-quinolinol: The Influence of Heat Treatment on Iodine Level, Macronutrient Composition and Antioxidant Content

Many disorders are a result of an inadequate supply of macronutrients and micronutrients in the diet. One such element is iodine. This study used curly kale (Brassica oleracea var. Sabellica L.) biofortified with the 5,7-diiodo-8-quinolinol iodine compound. The effect of the heat treatment on the chemical composition of the curly kale was studied. In addition, iodine bioavailability was evaluated in in vivo studies. Our investigation showed that iodine loss depends on the type of heat treatment as well as on the variety of kale. Curly kale biofortified with iodoquinoline had significantly higher iodine levels after thermal processing (steaming, blanching, boiling) than the vegetable biofortified with KIO3. Generally, steaming was the best thermal processing method, as it contributed to the lowest iodine loss in curly kale. The red variety of kale, 'Redbor F1', showed a better iodine stability during the heat treatment than the green variety, 'Oldenbor F1'. The thermal treatment also significantly affected the dry matter content and the basic chemical composition of the tested varieties of the 5,7-diI-8-Q biofortified kale. The steaming process caused a significant increase in total carbohydrates, fiber, protein and crude fat content ('Oldenbor F1', 'Redbor F1'), and antioxidant activity ('Oldenbor F1'). On the other hand, boiling caused a significant decrease, while steaming caused a significant increase, in protein and dry matter content ('Oldenbor F1', 'Redbor F1'). The blanching process caused the smallest significant decrease in ash compared to the other thermal processes used ('Oldenbor F1'). A feeding experiment using Wistar rats showed that iodine from the 5,7-diI-8-Q biofortified kale has a higher bioavailability than that from the AIN-93G diet. A number of promising results have been obtained, which could form the basis for further research.

Apple Pomace as an Ingredient Enriching Wheat Pasta with Health-Promoting Compounds

The global overproduction of apples is associated with large amounts of post-production waste, for which new forms of utilization should be sought. Therefore, we aimed to enrich wheat pasta with apple pomace in various percentages (10, 20, 30 and 50%). The content of total polyphenols, individual polyphenols (using UPLC-PDA-MS/MS methods) and dietary fibre, chemical composition and physical properties of the resulting pasta were determined. The addition of apple pomace to pasta resulted in increased levels of pro-health compounds: total polyphenols, phenolic acids, quercetin derivatives, flavon-3-ols and dihydrochalcones as well as dietary fibre. Decreases in hardness and maximum cutting energy were also observed in pasta supplemented with apple pomace compared to control pasta. Water absorption capacity was not influenced by the addition of apple pomace, with the exception of pasta made with 50% apple pomace.

Red Arils of Taxus baccata L.-A New Source of Valuable Fatty Acids and Nutrients

The aim of this study, focused on the nutritional value of wild berries, was to determine the contents of macronutrients, profiles of fatty (FAs) and amino acids (AAs), and the contents of selected elements in red arils (RA) of Taxus baccata L., grown in diverse locations in Poland. Protein (1.79–3.80 g/100 g) and carbohydrate (18.43–19.30 g/100 g) contents of RAs were higher than in many cultivated berries. RAs proved to be a source of lipids (1.39–3.55 g/100 g). Ten out of 18 AAs detected in RAs, mostly branched-chain AAs, were essential AAs (EAAs). The EAAs/total AAs ratio approximating were found in animal foods. Lipids of RA contained seven PUFAs, including those from n-3 family (19.20–28.20 g/100 g FA). Polymethylene-interrupted FAs (PMI-FAs), pinolenic 18:3Δ5,9,12; sciadonic 20:3Δ5,11,14, and juniperonic 20:4Δ5,11,14,17, known as unique for seeds of gymnosperms, were found in RAs. RAs may represent a novel dietary source of valuable n-3 PUFAs and the unique PMI-FAs. The established composition of RAs suggests it to become a new source of functional foods, dietary supplements, and valuable ingredients. Because of the tendency to accumulate toxic metals, RAs may be regarded as a valuable indicator of environmental contamination. Thus, the levels of toxic trace elements (Al, Ni, Cd) have to be determined before collecting fruits from natural habitats.

Effect of the method of preparation for consumption on calcium retention, calcium:phosphorus ratio, nutrient density and recommended daily allowance in fourteen vegetables

The aim of this work was to evaluate calcium retention in 14 species of vegetable (from four usable groups). The material investigated consisted of raw and boiled fresh vegetables and two types of frozen product prepared for consumption after 12-month storage: one traditionally produced; the other obtained using the modified method (convenience food). The highest calcium content was found in leafy vegetables, followed (in descending order) by leguminous, root and brassica vegetables. The proportion by weight of Ca to P was highest in leafy vegetables and decreased with calcium retention despite the fact that levels of phosphorus were highest in leguminous and lowest in leafy vegetables. The nutrient density (ND%) of calcium for adults exceeded 100 for each individual vegetable species. The recommended daily allowance (RDA) percentage value varied between 23.04 (kale) and 1.46 (white cauliflower). Of the three types of product, ND and RDA values were generally greater in the frozen convenience products.

Changes due to cooking and sterilization in low molecular weight carbohydrates in immature seeds of five cultivars of common bean

Immature seeds of five bean cultivars (flageolet-type and those intended for dry-seed production) were assessed for changes in water-soluble carbohydrates including raffinose family oligosaccharides (RFOs) due to boiling, sterilization, and storage of the sterilized product. About 100 g fresh weight of edible portion of fresh bean seeds contained 2449.3-3182.6 mg total soluble sugars, of which RFOs comprised 44-49%. The highest amounts of these compounds were found in the seeds of the cultivars Laponia and Mona. The dominant oligosaccharide was stachyose. Boiling fresh seeds to consumption consistency reduced total soluble sugars and RFOs: average values were 57% and 55%, respectively. Sterilization in cans resulted in 65% reductions of both total soluble sugars and RFOs. In general, there were no changes in the content of soluble sugars in canned and sterilized products stored for 12 months.

Minerals and chosen heavy metals retention in immature common bean (Phaseolus vulgaris L.) seeds depending on the method of preservation

BACKGROUND

Legumes are a good source of protein, and are also abundant in carbohydrates, B-group vita-mins, dietary fibre and mineral compounds.

MATERIAL AND METHODS

This work evaluates the retention of ash, eleven minerals and two heavy metals in products obtained from two common bean cultivars harvested before reaching full maturity, with a dry matter content of about 40%. Analyses were conducted on raw, blanched and cooked seeds and three products prepared for consumption after 12-month storage: two frozen and one canned (sterilized). The former comprised two types of frozen product: one traditionally produced (blanching-freezing-frozen storage-cooking), the other a convenience, "ready-to-eat" product obtained using a modified method (cooking-freezing-frozen storage-defrosting-heating to consumption temperature in a microwave oven).

RESULTS

In cooked bean seeds of both cultivars, levels of potassium, calcium, magnesium and copper were significantly lower, the only exception being the content of ash and sodium (due to added salt), than in blanched seeds; the changes in the remaining components were not so clear-cut and depended on the cultivar. Seeds frozen using the modified technology generally showed higher levels of the elements investigated than frozen products produced traditionally, with the exception of chromium, nickel and lead. Sterilized seeds had lower levels of ash, phosphorus, calcium, magnesium, iron, zinc, manganese, copper and chromium compared with both types of frozen product; retention levels of individual components depended on the cultivar examined. Conclusions. Compared with the traditionally produced frozen product, prepared for consumption, seeds after modified method of freezing (convenience food) contained significantly higher levels of ash and all macroelements, regardless of the cultivar. Seeds preserved by sterilization, compared with frozen seeds (either method of production) prepared for consumption, had lower content of most of the analyzed components.

Tocopherol retention and vitamin E activity in frozen and canned immature seeds of five cultivars of common bean

BACKGROUND

This paper investigates tocopherol retention and vitamin E activity in the seeds of five bean cultivars (flageolet type and grown mostly for their dry seeds) harvested at the wax stage of maturity. Seeds were analyzed raw, cooked and in three products prepared for consumption after 0 and 12 months of storage. These comprised frozen products obtained using the traditional method (blanching-freezing-frozen storage-boiling) and a modified method (boiling-freezing-frozen storage-defrosting and heating in a microwave oven), and canned products.

RESULT

Total tocopherols in fresh bean seeds were within the range 18.53-25.98 mg kg(-1) of edible portion. The most abundant form of tocopherol found in fresh seeds was γ-T isomer (87-91% of the total), followed by the α-T (5-7%) and δ-T (3-5%) forms; the β-T form was not detected. Cooking resulted in a 13-28% decrease in total tocopherols and a 17-31% reduction in vitamin E activity. In products prepared for consumption after 12 months' storage, total tocopherols and vitamin E activity were 13-53% and 23-60% lower, respectively, than in fresh seeds, with the highest losses being mainly in α-T content.

CONCLUSION

The variety and cultivar or method of preservation had no effect on either tocopherol retention or vitamin E activity.

Evaluation of the effect of pretreatment and preservation on macro- and microelements retention in flageolet (Phaseolus vulgaris L.) bean seeds

BACKGROUND

Legume seeds, including beans, are a good source of mineral constituents. The level of these compounds depends among other factors, on the species, cultivar and the methods of processing applied. However, there are no studies in the literature which deal with the content of mineral constituents in physiologically immature bean seeds.

MATERIAL AND METHODS

The aim of this study was to evaluate the retention of ash and 13 mineral constituents in immature seeds of three bean cultivars. The investigation included raw, blanched and cooked seeds and three products prepared for consumption after 12-month storage: a frozen product obtained using the traditional method (blanching-freezing-frozen storage-cooking); a frozen product obtained using the modified method (cooking-freezing-frozen storage-defrosting and heating in a microwave oven); and a sterilized canned product.

RESULTS

The application of technological processes; the storage of frozen and sterilized products; and the preparation of frozen products for consumption had an effect on minerals content in finished products. The frozen product obtained using the modified method retained greater amounts of the investigated elements (apart from calcium, lead and cadmium) than the traditional frozen product. Canned bean seeds retained less ash, phosphorus, potassium, calcium, magnesium, sodium and iron than the products of the two ways of freezing, while the retention of the remaining constituents depended on the cultivar.

CONCLUSIONS

Modified method of freezing of immature bean seeds resulted in greater retention of the investigated components in products prepared for consumption than the traditional method of freezing or canning.