Teresa Mazzeo

Effect of different cooking methods on color, phytochemical concentration, and antioxidant capacity of raw and frozen Brassica vegetables.

This study evaluated the effect of common cooking practices (i.e., boiling, microwaving, and basket and oven steaming) on the phytochemical content (carotenoids, chlorophylls, glucosinolates, polyphenols, and ascorbic acid), total antioxidant capacity (TAC), and color changes of three generally consumed Brassica vegetables analyzed fresh and frozen. Among cooking procedures, boiling determined an increase of fresh broccoli carotenoids and fresh Brussels sprout polyphenols, whereas a decrease of almost all other phytochemicals in fresh and frozen samples was observed. Steaming procedures determined a release of polyphenols in both fresh and frozen samples. Microwaving was the best cooking method for maintaining the color of both fresh and frozen vegetables and obtaining a good retention of glucosinolates. During all cooking procedures, ascorbic acid was lost in great amount from all vegetables. Chlorophylls were more stable in frozen samples than in fresh ones, even though steaming methods were able to better preserve these compounds in fresh samples than others cooking methods applied. The overall results of this study demonstrate that fresh Brassica vegetables retain phytochemicals and TAC better than frozen samples.

Total Antioxidant Capacity of the Diet Is Associated with Lower Risk of Ischemic Stroke in a Large Italian Cohort

Experimental studies suggest that oxidative stress and systemic inflammation are involved in the pathogenesis of ischemic stroke. Consuming a diet with a high total antioxidant capacity (TAC) has been related to reduced inflammation and increased circulating antioxidants in cross-sectional and randomized intervention studies. This study investigates the relation between dietary TAC and risk of ischemic and hemorrhagic stroke in 41,620 men and women not previously diagnosed with stroke or myocardial infarction, representing the Italian segment of the European Prospective Investigation into Cancer and Nutrition. Controlling for potential confounders, a diet rich in TAC was associated with a reduction in HR for all types of stroke, but this association was only marginally significant (P-trend = 0.054). When only ischemic stroke cases were considered, data suggest a stronger inverse association with dietary TAC, with HR = 0.41 (95% CI = 0.23-0.74). Regarding single antioxidants, data from subanalyses on stroke types suggest that vitamin C is significantly associated with a decreased risk of ischemic stroke [HR = 0.58 (95% CI = 0.34-0.99)], whereas vitamin E was associated with increased HR of hemorrhagic stroke in the highest tertile of intake [HR = 2.94 (95% CI = 1.13-7.62)]. In conclusion, our findings suggest that antioxidants may play a role in reducing the risk of cerebral infarction but not hemorrhagic stroke. However, a high intake of vitamin E could be positively associated to the risk of brain hemorrhagic events; therefore, more focused investigations about this observation are needed.

Effect of cooking on the total antioxidant capacity and phenolic profile of some whole‐meal African cereals

BACKGROUND At present, sorghum, fonio and millet are not placed as important commodities in the North American and European food basket, but their importance as ingredients in multigrain and gluten-free cereal products is highlighted. Therefore in this study the phenolic profile (evaluated by liquid chromatography/tandem mass spectrometry), total phenolic content (assessed by Folin-Ciocalteu assay) and total antioxidant capacity were measured in three African whole grains, i.e. sorghum (Sorghum bicolor ssp. bicolor), fonio (Digitaria exilis) and pearl millet (Pennisetum glaucum L.), before and after a cooking procedure. RESULTS After the cooking process, soluble phenolic acids increased significantly in sorghum, whereas bound ones and anthocyanins decreased significantly. In millet the cooking process significantly enhanced soluble phenolic acids without affecting those bound, whereas in fonio a slight but significant decrease in almost all soluble phenolic acids was observed along with a significant increase in bound ones. Finally, the cooking process negatively affected both total phenolic content and total antioxidant capacity. CONCLUSION This is one of the few reports dealing with the antioxidant compounds of these three African whole grains in which the effect of cooking was also evaluated. The data suggested that, to improve their antioxidant properties, specific cultivars should be selected and the cooking procedures carefully considered.

Compositional Study and Antioxidant Potential of Ipomoea hederacea Jacq. and Lepidium sativum L. Seeds

The present investigation has been carried out to determine the proximate composition, amino acids, metal contents, oil composition as well as the antioxidant capacity of the seeds of Ipomoea hederacea Jacq. and Lepidium sativum L. Proximate composition indicated a great difference in oil (14.09 ± 0.66, 28.03 ± 1.05) and fibre (16.55 ± 0.31, 6.75 ± 1.20) contents for I. hederacea and L. sativum, respectively. Fatty acid profile indicated that oleic acid (19.50 ± 0.37, 30.50 ± 0.16) and linoleic acid (52.09 ± 0.48, 8.60 ± 0.38) are the major fatty acids. γ-Tocopherol and δ-tocopherol (28.70 ± 0.14, 111.56 ± 0.37) were the most abundant in the seed oil of I. hederacea and L. sativum, respectively. Results of TEAC, FRAP and TRAP antioxidant assays indicated that L. sativum has much greater antioxidant potential than I. hederacea.

The development of a composition database of gluten-free products.

OBJECTIVE To develop a composition database of a number of foods representative of different categories of gluten-free products in the Italian diet. DESIGN The database was built using the nutritional composition of the products, taking into consideration both the composition of the ingredients and the nutritional information reported on the product label. SETTING The nutrient composition of each ingredient was obtained from two Italian databases (European Institute of Oncology and the National Institute for Food and Nutrition). SUBJECTS The study developed a food composition database including a total of sixty foods representative of different categories of gluten-free products sold on the Italian market. The composition of the products included in the database is given in terms of quantity of macro- and micronutrients per 100 g of product as sold, and includes the full range of nutrient data present in traditional databases of gluten-containing foods. RESULTS As expected, most of the products had a high content of carbohydrates and some of them can be labelled as a source of fibre (>3 g/100 g). Regarding micronutrients, among the products considered, breads, pizzas and snacks were especially very high in Na content (>400-500 mg/100 g). CONCLUSIONS This database provides an initial useful tool for future nutritional surveys on the dietary habits of coeliac people.

Nutritional Quality of Sous Vide Cooked Carrots and Brussels Sprouts

Phytochemicals (carotenoids, phenolic compounds, and ascorbic acid) and antioxidant capacity (measured by TEAC, FRAP, and TRAP assays) were evaluated on carrots and Brussels sprouts sous vide processed and then stored refrigerated for 1, 5, and 10 days and compared with the corresponding raw and oven-steamed products. Data showed that sous vide cooked carrots had higher amounts of carotenoids, phenolic compounds, and ascorbic acid than steamed products, and only a slight decrease of phenolic compounds was recorded during sous vide storage. Contrasting results were obtained on sous vide processed Brussels sprouts: higher carotenoid amounts and TEAC and TRAP values and lower phenolic compounds, ascorbic acid, and FRAP values were exhibited by sous vide in comparison with steamed samples. Phytochemicals and TAC also decreased during Brussels sprout sous vide storage with the exception of carotenoids. The results of this study demonstrated that sous vide preparation can preserve and/or enhance the nutritional quality of carrots, which remain a good source of carotenoids also after long refrigerated storage, whereas the same treatment could be recommended as an alternative to oven-steaming in the preparation of Brussels sprouts for short-term maintenance to avoid a large ascorbic acid depletion.

Impact of the industrial freezing process on selected vegetables -Part II. Colour and bioactive compounds

In the present study, the impact of the different steps (i.e. blanching, freezing, storage following the industrial freezing process and the final cooking prior to consumption) of the industrial freezing process was evaluated on colour, chlorophylls, lutein, polyphenols and ascorbic acid content of asparagus, green beans and zucchini. In addition, the domestic boiling of raw samples was compared with the boiling of frozen storage vegetables. Results showed that the blanching treatment retained phytochemicals in all studied green vegetables and the frozen storage up to 2months did not negatively affected phytochemicals, in particular lutein and flavonoids in almost all samples. On the contrary, colour significantly changed during blanching and frozen storage. The changes of b* (yellowness) and the shift of H° (hue angle) were not coherent with the increase of pheophytin. In addition, the greenness (-a*) was found to increase with the exception of boiled samples in all vegetables. Generally, in boiled frozen vegetables there was a better or comparable retention of bioactive compounds with respect to raw ones, and this was especially true for green beans and zucchini. Colour changes after cooking did not exhibit the same trends among vegetables, being more remarkable for frozen asparagus in comparison with those boiled from raw, but overall comparable for green beans and zucchini. In conclusion, the overall results of the present study suggest that, when the industrial freezing process is well performed, the boiled frozen vegetables do not have a lower nutritional value than the fresh ones.

Anti-proliferative activity and chemoprotective effects towards DNA oxidative damage of fresh and cooked Brassicaceae

Epidemiological evidence shows that regular consumption of Brassicaceae is associated with a reduced risk of cancer and heart disease. Cruciferous species are usually processed before eating and the real impact of cooking practices on their bioactive properties is not fully understood. We have evaluated the effect of common cooking practices (boiling, microwaving, and steaming) on the biological activities of broccoli, cauliflower and Brussels sprouts. Anti-proliferative and chemoprotective effects towards DNA oxidative damage of fresh and cooked vegetable extracts were evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium and Comet assays on HT-29 human colon carcinoma cells. The fresh vegetable extracts showed the highest anti-proliferative and antioxidant activities on HT-29 cells (broccoli>cauliflower = Brussels sprouts). No genotoxic activity was detected in any of the samples tested. The cooking methods that were applied influenced the anti-proliferative activity of Brassica extracts but did not alter considerably the antioxidant activity presented by the raw vegetables. Raw, microwaved, boiled (except broccoli) and steamed vegetable extracts, at different concentrations, presented a protective antioxidative action comparable with vitamin C (1 mm). These data provide new insight into the influence of domestic treatment on the quality of food, which could support the recent epidemiological studies suggesting that consumption of cruciferous vegetables, mainly cooked, may be related to a reduced risk of developing cancer.

Evaluation of visual and taste preferences of some gluten-free commercial products in a group of celiac children.

Abstract The purpose of this study was to investigate the visual and taste liking of three commercial gluten-free (GF) foods in a group of celiac children. Thirty celiac children, with diagnosis of celiac disease from more than 2 years, were recruited and 28 (21 females and 7 males, mean age 8.7 years) completed the study. Subjects performed individually six sensory tests, two for each product in different days separated by a week. In the test day, children had to evaluate the liking of the same type of product but of different four brands, before and after tasting them with a 5-point facial rating scale. Overall, the results showed that the majority of children appreciated more the appearance than the taste of all the GF products analysed. The present study provides the first and useful indications on the hedonic perceptions of celiac children about some commercial GF products.

Phenolic profile and antioxidant potential of selected plants of Pakistan

Antioxidants play an important role in inhibiting and scavenging radicals, thus providing protection to humans against infectious and degenerative diseases. Literature shows that the antioxidant activity is high in medicinal plants. Realizing the fact that, this investigation was carried out to evaluate the in vitro antioxidant capacity of methanolic extracts of Acacia leucophloea (bark), Albizia lebbeck (bark, flower, seed), Capparis decidua (root), Cicer arietinum (seeds) and Grewia asiatica (leaves). Barks showed the highest phenolic content as compared to seeds, leaves and roots and the order observed was A. lebbeck bark> A. leucophloea bark> G. asiatica leaves> C. decidua root >A. lebbeck flowers> A. lebbeck seeds> C. arietinum seeds. Phenolic compounds were identified based on their mass spectral characteristics in each extract. Antioxidant capacity measured by three commonly-benched methods, TEAC, FRAP and TRAP assays indicated that all extracts are a good source of natural antioxidants. Investigated extracts appeared to have potential as a health supplement rich in natural antioxidants and merits further intensive study. The results of this study will promote the reasonable usage of these plants in food and pharmacy industries as well as in alternative medicine and natural therapy.