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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. [ABSTRACT FROM AUTHOR]

In Poland, the mountainous and hilly regions until recently were territories with unbalanced and poor diet quality, especially in early spring. Wild edible plants were or remain influential in supplementing a human diet. One of the earliest wild edible plants to appear in the growing season, characteristic of a broad swath of Europe from Ukraine to Germany, remains wild (ramsons) garlic (Allium ursinum L.). This paper assesses the impact of the vegetation site and preservation methods on the content of chlorophylls, β-carotene, vitamin C, total polyphenols, and antioxidant activity (ABTS, DPPH, and FRAP) of wild garlic leaves. In addition, the connection between its genome pattern and chemical composition was assessed. The plants were collected in three locations in the Carpathian foothills, and the reference sample was plants collected in the lowlands. The site from which the raw material was harvested has a statistically significant effect on the chemical composition of the preserved leaves of wild garlic. The profiles of the analysed components differed in the material from a different site. Wild garlic leaves from mountainous areas (400–600 m above sea level) were characterized by a higher content of the analysed ingredients than leaves obtained from lowland sites (200 m above sea level). Moreover, the material from the lowlands had a different genetic pattern from the leaves from the mountainous areas. [ABSTRACT FROM AUTHOR]

In this study we tested the hypothesis that a product subjected to a single treatment in water (modified technology - a convenience food) will contain more magnesium than the one subjected to a twofold treatment (traditional technology). Moreover, with higher magnesium retention, the nutrient density (ND) of the product will also be higher, as will be the intake of magnesium in a portion of vegetables expressed as a percentage of recommended dietary allowance (RDA). In fresh vegetables, the highest magnesium content was found in spinach and the lowest in white cauliflower. In vegetables prepared for consumption, magnesium retention was highest in frozen products obtained using the modified technology, followed by cooked fresh vegetables, with the lowest retention in product obtained using the traditional technology. The above sequence of magnesium content also applied to ND and RDA values, the ND values easily exceeding 100% for all the samples examined. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The aim of the present work was to evaluate the retention, the nutrient density and the recommended daily allowance of zinc in 14 common vegetable species prepared for consumption. The investigation included fresh vegetables, vegetables after traditional cooking in brine and two types of frozen products: one obtained using the traditional method (blanching-freezing-storage-cooking in brine) and the other obtained using the modified method, providing a ready-to-eat product (cooking in brine-freezing-storage-defrosting and heating in a microwave oven). A significant zinc decrease was found in most studied vegetables prepared for consumption. Application of the modified method contributed to a reduction in zinc losses in prepared-for-consumption frozen vegetables. [ABSTRACT FROM AUTHOR]

Abstract: The content of ash, P, K, Ca, Mg, Na, Fe, Zn, Mn, Cu, Cr and Ni was compared in kale, spinach and New Zealand spinach: fresh, frozen and prepared for consumption. The investigation covered composition of the raw vegetables; the vegetables blanched in water before freezing (the traditional method of freezing); the vegetables cooked in brine (the modified method of freezing); and frozen products after 12 months of refrigerated storage. These products were prepared for consumption: either by cooking the products obtained by the traditional method in brine; or by defrosting and heating frozen vegetables obtained by modified method to consumption temperature in a microwave oven. The smallest losses caused by blanching were usually found in spinach and the highest in kale. Changes caused by cooking did not always exceed those noted after blanching. When compared with the raw vegetables, frozen products prepared for consumption contained significantly less potassium, magnesium and – with the exception of New Zealand spinach – phosphorus and copper. There was also a decrease in calcium, but only in kale; and in chromium and nickel, but only in New Zealand spinach. With regard to the remaining elements there was no consistent pattern. In products obtained by the modified method, the content of analysed constituents was greater in almost every case compared with that obtained using the traditional method; however, not all the differences were statistically significant. [Copyright &y& Elsevier]

Abstract: The investigation concerned frozen broccoli produced using a traditional method, i.e. from the raw material blanched before freezing, and a modified method of freezing cooked broccoli. In comparison with blanched broccoli the material cooked before freezing contained more dry matter, carotenoids and beta-carotene and less vitamin C and polyphenols; its antioxidative activity was also poorer. In frozen products stored for 0, 4, 8 and 12 months at −20 or −30 °C and then cooked, a steady decrease was observed in the content of all the constituents. Compared with the raw material cooked broccoli stored for 12 months contained 29–33% of vitamin C, 54–66% of polyphenols, 80–97% of carotenoids, 69–80% of beta-carotene and showed a 29–35% decrease in the antioxidative activity. A higher or similar level of the above properties was found in samples cooked before freezing as compared with blanched goods; a higher level was ascertained in samples stored at −30 °C compared with those stored at −20 °C. The same sensory quality was found for frozen goods obtained with both methods. Frozen products and ready-to-eat frozen products stored at −30 °C had higher sensory quality. Industrial relevance: Ready to eat vegetable products are more and more popular among individual consumers and catering services. The present work compared quality of traditional frozen broccoli and ready to eat frozen broccoli, both prepared for consumption. After long term frozen storage a higher or similar level of antioxidants was found in ready to eat type as compared with traditional type, and sensory quality of both types was at least good. Products stored at −30 °C retained more antioxidants and revealed better sensory quality than ones stored at −20 °C. [Copyright &y& Elsevier]

The aim of this work was to evaluate the level of total glucosinolates (GLS) in fresh kale leaves and leaves after processing (blanching, cooking), as well as in frozen, canned and dried products after 1-year storage. Fresh kale leaves contained 26.87 μmol GLS per 1 g dry weight, of which aliphatic GLS comprised 63%. GLS levels in kale leaves were affected by blanching and cooking; losses were highest in leaves preserved by sterilization and lowest in frozen leaves. After 12 months of storage, mean amounts of total GLS in frozen and canned products were 15.59 μmol and 10.73 μmol respectively per 1 g. In dried products, mean total GLS levels ranged from 9.09 to 13.81 μmol, being significantly (on average 13%) higher in freeze-dried products than in those dried by hot air. Moreover, dried products obtained from blanched leaves showed higher mean amounts of total GLS than those obtained from unblanched leaves. Frozen products from blanched material contained the highest amounts of GLS; total GLS were average 20% higher than in frozen products obtained from cooked raw material, 58%, higher than in canned products, and 47% higher than in dried products. Aliphatic glucosinolates were usually more stable than indole GLSs. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the work was to evaluate the amino acid composition of fresh spinach and spinach products prepared for consumption. The investigation included fresh and cooked spinach and two kinds of frozen product: one obtained using the traditional method (blanching-freezing-refrigerated storage) and then cooked; and the other, of the ready-to-eat type, obtained using the modified method (cooking-freezing-refrigerated storage) and then prepared for consumption in a microwave oven. In 100g of edible parts of the as-eaten products, the content of amino acids exceeded that in the raw material from which they were obtained, except for sulphur amino acids and tyrosine. In the as-eaten products, the content of amino acids in protein calculated in 16g N was similar to that in the raw material, except for lower tyrosine and higher arginine content in the traditional frozen product prepared for consumption. Cystine with methionine was the amino acid limiting the quality of protein in the investigated samples, except for the traditional frozen product prepared for consumption, where the Chemical Score (CS) index was 100. [Copyright &y& Elsevier]

Green pea is regarded as an important constituent of a human diet, especially for vegetarians. The aim of the present work was to evaluate the amino acids content in green pea and the quality of pea protein. The study covered raw seeds; fresh seeds cooked to consumption consistency; and two kinds of frozen products prepared for consumption: frozen seeds obtained using the traditional method and frozen seeds of the ready-to-eat type. Compared with the raw material, cooked fresh pea contained more isoleucine (15%), valine (14%) and arginine (24%) but less tyrosine (17%); cooked pea from the traditional frozen product contained less sulphur-containing amino acids (12%) and alanine (13%); while pea from the frozen product of the ready-to-eat type contained a similar or higher amount (from 12% to 38%) of amino acids, except for sulphur-containing amino acids (less 12%). The protein of green pea was of very good quality, both in raw seeds and in those prepared for consumption. In comparison with the FAO/WHO/1991 standard, the CS indexes exceeded 100. It was only for sulphuric amino acids that the CS for the ready0to-eat product was 98. The methods of culinary and technological processing applied affected the quality of protein in green pea seeds to a negligible degree. [ABSTRACT FROM AUTHOR]