Nutritional composition of freshly harvested and stored Latvian potato (Solanum tuberosum L.) varieties depending on traditional cooking methods

The information about nutritional composition of potatoes at both the ingredient and recipe levels in the Food Composition Data Base (FCDB) of Latvia is insufficient. Therefore, the aim of this research was to determine the nutritional composition and energy content of potatoes prepared by traditional cooking methods before and after storage. Five Latvian potato varieties were selected: Lenora, Brasla, Imanta, Zile and Madara. A two-year research was conducted during two periods: just after harvesting (2007, 2008) and after six months of storage (2008, 2009). The following cooking methods were used: shallow frying (150 ± 5 °C); deep-fat frying (180 ± 5 °C) and roasting (210 ± 5 °C). The weight of the potatoes was recorded before and after frying along with the time and temperature during frying. Chemical analyses were performed to determine the content of reducing sugars, starch, fructose, glucose, sucrose, fibre, fat, protein, moisture, vitamin C and amino acids. The content of the analyzed nutrients differed significantly between both potato varieties and applied cooking methods: differences between potato varieties and cooking methods were found for vitamin C, moisture, reducing sugars, fructose, glucose, sucrose, amino acids, essential amino acids, and energy content, whereas significant differences in starch, fibre, fat and protein content were found between cooking methods.     

Effect of dehulling and cooking on nutritional quality of chickpea (Cicer arietinum L.) germinated in mineral fortified soak water

The objective of the study was to fortify whole chickpea (Cicer arietinum L.) with iron and zinc through germination in mineral fortified soak water and analyze the effect of dehulling and cooking on its nutritional quality. Whole chickpea grains were soaked in water fortified with either zinc or iron at two levels and germinated. Grains germinated in plain water served as control. One portion of germinated grains was dehulled. Both whole and dehulled grains were cooked (under pressure or microwave) and analyzed for selected total and in vitro digestible starch and protein, and bioaccessible iron, zinc and calcium following standard techniques. Grains germinated in fortified water had higher content and bioaccessibility of iron and zinc in whole and dehulled grains. Dehulling improved the digestible starch and protein, and bioaccessible zinc and calcium, whereas bioaccessible iron was higher in whole grains. Cooking improved starch digestibility significantly, though did not alter iron and zinc bioaccessibility. In conclusion, iron and zinc fortification of chickpea through germination in fortified soak water improved the content and bioaccesssibility of added minerals both in whole and dehulled grains and can be advocated as a simple technique to improve micronutrient malnutrition.     

Nutritional composition of Plantago species (P. Major L., P. Lanceolata L., and P. Media L.)

Analyses of the nutrients are given for the leaves of wild Plantago major L., P. lanceolata L. and P. media L., from different locations of the southeast of Spain. The proximate composition, mineral elements (Na, K, Ca, Mg, Fe, Cu, Zn, Mn and P), fatty acids, vitamins (vitamin C and carotenes), nitrate and oxalic acid were determined. The results show the low proportion of available carbohydrates, ranging from 1.99 g (P. major) to 2.81 g (P. lanceolata) (per 100 g fresh weight). Oxalic acid was found in low amounts, between 33.5 mg (P. media) and 88.2 mg (P. lanceolata) (100 g f wt). P. major had the highest amounts of vitamin C (45.1 mg/100g f. wt.) and calcium (108mg/100g f. wt.). Polyunsaturated fatty acids were high in all species, ranging from 38.97% (P. media) to 46.07% (P. lanceolata). Nutrient ratios (K/Na; Ca/P and oxalic acid/Ca) were found to be favourable in most cases.     

Nutritional content and bioactive properties of wild and farmed cod (Gadus morhua L.) subjected to food preparation

Cod is a relatively new species in intensive aquaculture. The aim of this study was to compare the nutritional composition and bioactive properties of wild and farmed cod as well as investigate how cooking influenced these parameters. Wild cod contained significantly more docosahexaenoic acid, whereas the levels of linoleic acid, eicosapentaenoic acid, and docosapentaenoic acid were lower than in farmed cod. Only minor difference in amino acid profile were found between wild and farmed cod but protein content was higher in the latter. Baking resulted in lower loss of moisture and a corresponding lower loss of taurine compared to poaching. The angiotensin converting enzyme (ACE) inhibitory capacity did not differ between wild and farmed cod (IC₅₀ values of 0.06 mg/mL) nor was it significantly affected by cooking. From this study, it is evident that intake of wild and farmed cod provides similar health-promoting effects that are maintained during cooking.     

Bioactive compounds and antioxidant activities of different watermelon (Citrullus lanatus (Thunb.) Mansfeld) cultivars as affected by fruit sampling area

This investigation reports the variability of antioxidant components and antioxidant activities of six watermelon cultivars (cvs) (four commercial cvs Aramis, Crimson Sweet, Dumara, Giza, and two new selections P503 and P403 produced by the National Agricultural Research Institute of Tunisia) as influenced by sampling area. All cvs were simultaneously grown in an open-field and subjected to identical horticultural practices in order to minimize the effects of environmental conditions and maximize those related to genotype. Significant differences were found between watermelon cvs for lycopene, phenolics, flavonoids, ascorbic acid (AsA), dehydroascorbic acid (DHA) and total vitamin C (AsA + DHA) contents, as well as in the antioxidant activity of their hydrophilic and lipophilic fractions. P503 cv showed the highest lycopene and flavonoid contents. Crimson Sweet and Giza cvs showed the highest HAA and LAA when TEAC was used as assay method, while the highest HAA and LAA were detected in Giza and Dumara cvs and in P503 cv, respectively, when FRAP assay was used. This study demonstrates that the amount of each specific antioxidant, as well as the HAA and LAA, were both influenced by genotype and sampling area, emphasizing the need to evaluate watermelon biodiversity in order to improve its nutritional value.     

Nutritional,mineral and organic acid composition of syrups produced from six Moroccan date fruit (Phoenix dactylifera L.) varieties

Date syrup is the most common processed date product in Morocco, produced from surplus date fruit of inferior grades, which are not accepted by the food iandustry and sold at low prices. The present study aims to assess the physicochemical parameters and quality of syrups prepared using different date fruit varieties using traditional methods. In all analyzed syrups, sugar, primarily glucose and fructose, were the predominant elements. All syrups were characterized by a high ash content which mostly consisted of potassium, calcium, sodium and magnesium. Moreover, malic, succinic, acetic, citric and oxalic acids were found at higher concentrations. Besides their nutritional and functional composition, these date syrups are high in sugar, thus they might be used as sweetening agents instead of sugar which has no nutritional value. The high amount of hydroxymethylfurfural (HMF) and water activity established in these syrups might be indicative of bad manufacturing process and storage ability. Further studies are needed to optimize the syrup extraction and limit degradation byproducts in date syrups. Based on the results of this study, date syrup might serve as a good source of nutrients and can potentially be considered as a good functional food or functional food ingredient.     

Carotenoids and ascorbic acid composition from commercial products of cashew apple (Anacardium occidentale L.)

Carotenoids were determined by high-performance liquid chromatography (HPLC) and ascorbic acid (AA) by the official method of the Association of Official Analytical Chemists (AOAC) in cashew apple products found on the market of Campinas, Brazil. The following products, concentrated juice, frozen pulp, nectar, ready-to-drink, and sweetened concentrated juice, were analyzed, showing AA contents from 13.7 to 121.7 mg/100 g and total carotenoid levels ranging from 8.2 to 197.8 μg/100 g. β-Carotene was the main carotenoid in the majority of the products, followed by α-carotene, β-cryptoxanthin and 9-cis- +13-cis-β-carotene in similar proportions. However, in 10 of the 60 samples analyzed, another carotenoid pattern was found with the presence of auroxanthin, 5,8-epoxy-cryptoxanthin, 5,8-epoxy-lutein, ζ-carotene and two unidentified carotenoids. Cashew apple products were proved to be excellent sources of vitamin C, but not very good sources of carotenoids for the human diet.     

Nutritional values, metabolic profile and radical scavenging capacities of wild asparagus (A. acutifolius L.)

Wild asparagus, Asparagus acutifolius L., produces edible spears used in local diets of Mediterranean countries for millenia. Recently, interest has risen for its cultivation as frugal crop for niche markets, but only limited information exists on the nutritional values of this vegetable. In this paper, the nutritional values and metabolic profile (i.e. moisture content, total proteins, lipids and phenols, folic and ascorbic acids, ribose, arabinose, xylose, fructose, mannose, glucose, galactose, total and free aminoacids, and fatty acid composition) and radical scavenging capacities of spears of A. acutifolius from the Caserta area (southern Italy) were compared to those of the cultivated Asparagus officinalis L. On a fresh weight basis, proteins (4.83 vs. 3.62 g/100 g), essential amino acids (184.08 vs. 78.13 mg/100 g) and lipids (0.90 vs. 0.33 g/100 g) were higher in wild asparagus. Among the fatty acids, the two essential n-6 linoleic and n-3 alpha-linolenic, and palmitic acids were the most abundant in both species, representing about 90% of the total acids analysed. A. acutifolius contained comparable amounts of pentoses such as ribose (0.13 vs. 0.15 g/100 g) and xylose (0.17 vs. 0.14 g/100 g), and hexoses such as galactose (0.21 vs. 0.19 g/100g) and fructose (0.17 vs. 0.17 g/100 g), lower arabinose (0.27 vs. 0.39 g/100 g) and higher mannose (0. 90 vs. 0.49 g/100 g) and glucose (2.52 vs. 1.21 g/100 g) content, compared to A. officinalis. Folic acid was lower in A. acutifolius (47.5 vs. 80.6 μg), while ascorbic acid was more than fivefold higher (117 vs. 23 mg/100 g). Phenolic compounds were more abundant in A. acutifolius spears (41.97 vs. 27.62 mg/100 g) as was the radical scavenging activity against DPPH radical and nitric oxide. A. acutifolius appears nutritionally interesting for its high content in dry matter, proteins, lipids, phenols and for its strong antioxidant properties, raising interest for this potential new crop.     

Functional food characteristics of potato cultivars (Solanum tuberosum L.): Phytochemical composition and inhibition of 1-methyl-1-nitrosourea induced breast cancer in rats

Effects of freeze-dried potato powder, prepared from baked potato with skin and incorporated into a purified diet, on the post-initiation phase of chemically induced breast carcinogenesis in rats, were evaluated for both dose dependence and variation in anticancer activity among cultivars. Associations among anticancer activity, select phytochemicals, and antioxidant capacity were investigated. No adverse effects were observed in rats fed diets containing between 5% and 50% (w/w) freeze-dried potato powder. While Russet Burbank potato (RB) (5%, w/w) had marginal effects on the carcinogenic response, feeding a range of dietary concentrations (12.5%, 25%, and 50%, w/w), of a red pigmented cultivar, cv. Mountain Rose (MR), with higher content of chlorogenic acid derivatives and anthocyanin content than RB, showed greater inhibition of carcinogenesis. Overall, MR-fed rats had a 23% reduction in cancer incidence (p = 0.009) and a 49% reduction in cancer multiplicity (2.1 vs. 4.0 cancers per rat, p = 0.004) with evidence of a dose dependent effect on cancer multiplicity. Evaluation of additional cultivars showed significant variation for anticancer activity that is likely to be sufficient to build upon for crop breeding and improvement.     

Carotenoids, ascorbic acid, minerals, and total glucosinolates in choysum (Brassica rapa cvg. parachinensis) and kailaan (B. oleraceae Alboglabra group) as affected by variety and wet and dry season production

Choysum (Brassica rapa cvg. parachinensis) and kailaan (Brassica oleraceae Alboglabra Group) are economically and nutritionally important leafy brassicas in east and southeast Asia. We evaluated 22 commercial varieties of each crop in dry and wet season trials at the World Vegetable Center (AVRDC) to assess genetic diversity among varieties for phytonutrient content and phytonutrient yields (product of plot yield and plot nutrient content), and to measure the effect of season on phytonutrient content. The season strongly affected the content of most phytonutrients. Mean total carotenoid content of choysum and kailaan varieties declined by 37% and 23%, respectively, in wet season versus dry season trials. In contrast, calcium and ascorbic acid contents of both crops were about 50% and 20% higher in the wet season than in the dry season trial. Varietal variation for total carotenoids was about five-fold and four-fold, respectively, for choysum and kailaan in the dry season trial, and variation in iron content was about three-fold in the wet season trial. Several varieties of each crop ranked among the best varieties in both seasons for phytonutrient yield. Varieties outstanding for content of a particular phytonutrient tended to perform well in either dry or wet season, but not both.     

Proximate, unsaponifiable lipid and fatty acid composition of bogue (Boops boops) and horse mackerel (Trachurus trachurus) from the Italian trawl fishery

This study was aimed at evaluating the nutritional properties of bogue (Boops boops) and horse mackerel (Trachurus trachurus), fish species present throughout the Mediterranean and highly represented in the catch of the Italian trawl fishery. In Italy such fish species are scarcely known by consumers and are not sought-after on the market, especially when the fish are small. Proximates, unsaponifiables and fatty acid profile of bogue and horse mackerel caught by trawlers in different seasons of the year along the southern Adriatic coast of Italy were evaluated. Results showed that both species were characterised by good protein contents (18–20 g/100 g) and low lipid (1–2 g/100 g) and cholesterol (50–70 mg/100 g) levels at any season considered. Along with α-tocopherol (0.45–0.70 mg/100 g), δ-tocopherol was found at a lower level (0.04–0.09 mg/100 g) while no detectable amounts of the γ-isomer were observed in either species. The fatty acid profiles of horse mackerel and bogue exhibited a seasonal fluctuation. They were characterised by high proportions of polyunsaturated fatty acids (PUFA), ranging from about 30% of total fatty acids in summer to more than 40% of total fatty acids in spring and winter, and by high n-3/n-6 PUFA ratio values (4.4–6.8 for bogue, 7.4–8.2 for horse mackerel). On a quantitative basis, in bogue total n-3 PUFA amounted to 0.29–0.43 g out of 0.33–0.54 g of total PUFA per 100 g wet fillet. In horse mackerel total n-3 PUFA ranged between 0.37 g and 0.43 g/100 g and total PUFA between 0.41 and 0.49 g/100 g wet fillet. The atherogenic (0.46–0.63) and thrombogenic (0.22–0.38) indexes calculated on bogue and horse mackerel were comparable to those of fish species of higher commercial value. The nutritional properties of these underutilised species may be considered comparable to those of other low-fat fish species from the wild and also from aquaculture present on the Italian market and meeting consumers’ preferences.     

Influence of environment and genotype on polyphenol compounds and in vitro antioxidant capacity of native Andean potatoes (Solanum tuberosum L.)

The influence of environment and genetics on total phenolic content and hydrophilic antioxidant capacity (H-ORAC) of potato tubers was evaluated using 13 native Andean genotypes. Cultivars were grown at two highland locations in Peru: Huancayo and Huancani. Environmental conditions significantly affected the total phenolic contents and H-ORAC values in a cultivar-dependent manner. However, the potato genotype was the most determining factor of the observed variations. The effects of environment on individual phenolic compounds were also significant in terms of quantity, whereas the chemical profile remained stable across environmental conditions. To gain an insight into the observed antioxidant capacity of potato extracts, the individual and combined antioxidant effects of the main potato phenolic compounds were investigated. The ORAC values of reconstituted polyphenol mixtures reflecting the authentic phenolic composition of potato extracts were higher than expected from the summing of the ORAC values of individual phenolic compounds, indicating synergistic effects. The authentic potato extracts showed either a higher or a lower ORAC value than their reconstituted counterparts, suggesting positive or negative interactions with other compounds. Taken together, our results lead us to the following conclusions: (i) the hydrophilic antioxidant capacity observed in potato extracts is the result of various and complex interactions that could be attributed to phenolic compounds, to other non-identified molecules, and to synergistic as well as antagonistic effects between all these components and (ii) the high stability of the ranking of cultivars across environment in terms of phenolic content and antioxidant capacity indicates that the native Andean cultivars could be confidently used within breeding programs aiming at improving the health-promoting value of potato.     

Relationship between potato starch isolation methods and kinetic parameters of hydrolysis by free and immobilised α-amylase on alginate (from Laminaria digitata algae)

The kinetic study of the hydrolysis of starch, isolated by two methods (bisulphite and alkaline) from potatoes cultivated in the south of Algeria, was carried out by α-amylase (from Aspergillus oryzae). The enzyme used is free and immobilised by covalent bonds on alginate in the presence of the 1-ethyl-3-[3-(dimethylamino)-propyl]carbodiimide hydrochloride (EDCI). The kinetics of hydrolysis of the extracted starches obeys the Michaelis–Menten model. The values of k_m in g L⁻¹ and V_max in g L⁻¹ min⁻¹ for the starches isolated by the alkaline method are (40.7, 3.8) for free amylase and (70.8, 3.4) for the immobilised enzyme. For the starches extracted by the bisulphite method, the latter kinetic parameters values are (34.2, 2.8) for free amylase and (55.7, 1.7) for the immobilised enzyme. The results show that the kinetic parameters of the hydrolysis are dependent on the conditions of extraction and they are larger for the alkaline method for both the free and immobilised enzyme.