In this work, the impact of the industrial freezing process on structure, texture and total antioxidant capacity was studied using green asparagus stems, zucchini and green beans. Samples were ...analysed as raw/uncooked, blanched, raw/boiled and industrially frozen/boiled.
A consistent damage of the vegetable tissue was revealed by the histological analysis on vegetables boiled after freezing. The cells appeared to be dehydrated, contracted and separated at different levels depending on the anatomical structure of each vegetable.
The initial textural quality was partially retained in all blanched vegetables, and enhanced in cut tested asparagus stems, in relation to the action of phenolic acids at cell wall level. Raw/boiled and industrially frozen/boiled asparagus stems exhibited comparable forces of penetration and cut tests. On the other hand, zucchini, both raw and frozen, completely softened after boiling making the texture measurement impossible. Industrially frozen/boiled green beans showed higher values of cut and penetration forces, probably due to a higher presence of swollen cell walls, in comparison to those raw/boiled.
Blanching and boiling significantly increased the ferric reducing antioxidant power values of asparagus stems and green beans compared to uncooked/raw samples, while boiling after the freezing process significantly deprived both vegetables of the initial antioxidant capacity. On the other hand, boiling the frozen zucchini proved to be detrimental to the antioxidant capacity.
In conclusion, manufacturers and researchers should join together to develop specific industrial freezing process conditions according to the matrix of each vegetable.
•The impact of the industrial freezing process on selected vegetables is presented•Frozen boiled vegetables exhibit significant cell damage•A different retention of textural quality in processed vegetables is obtained•Frozen boiled vegetables show the lowest antioxidant capacity•Development of specific process conditions according to vegetable matrix is required
A simple and rapid procedure was developed for the direct measurement of the antioxidant capacity of cereals. It entails grinding of cereals, mixing with ...2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) reagent, centrifugation and measure of the absorbance. The ABTS reagent was dissolved in a mixture of ethanol:water (50:50, v/v), instead of 100% ethanol, in order to overcome low solubility of water-soluble antioxidant compounds of some cereals. A reaction time of 30
min allowed plateau values to be reached during the antioxidant capacity measurement of cereal samples. The accuracy of the direct procedure was confirmed by measuring, in solid state, the antioxidant activity of pure phenolic compounds.
The direct procedure gave results of total antioxidant capacities significantly higher than those determined by the traditional procedure (multiple extraction followed by alkaline hydrolysis) for most whole meal cereals, suggesting that such a procedure was not always sufficient to properly assess the antioxidant capacity of bound phenolic compounds in cereals. The proposed extraction-independent procedure for measuring antioxidant capacity of cereals will facilitate the inter-laboratory data comparison, the construction of reliable antioxidant capacity database and the screening of large sampling of cereals for their nutraceutical characteristics.
Reformulation of food products is one of the measures needed for reducing salt consumption. Accordingly, the World Health Organization (WHO) recently proposed global sodium benchmarks for different ...food categories to be used for setting national policies. Therefore, the sodium content of cereal-based products currently sold in Italy was compared with the WHO benchmarks, highlighting those categories primarily needing a reformulation. To this aim, the sodium content and several declarations (i.e., nutrition and health claims, organic or gluten free declaration) were retrieved from 2917 cereal-based products sold on the Italian market. All “minimally processed breakfast cereals” had a sodium content below the benchmark, while “flatbreads” and “leavened bread” had the highest percentage of items above the respective sodium benchmarks. Flatbreads and “crackers/savory biscuits” showed the highest median delta values from the respective benchmarks of 360 and 278 mg/100 g, respectively. Large variability in terms of percentage of products with sodium content above the benchmark was observed within the same categories, as well as among products with different declarations. A large number of food products currently sold on the Italian market have a sodium content above the benchmark. This result suggests the need to reformulate many food products currently on the market to achieve the WHO/United Nations (UN) objective of 30% global reduction in sodium intake by 2025.
With the aim to expand the Italian total antioxidant capacity (TAC) database, the TAC values of 11 spices, 5 dried fruits, 7 sweets, 18 cereal products, 5 pulses, and 6 nuts were determined using ...three different assays and considering the contribution of bound antioxidant compounds in fiber‐rich foods (i. e. cereals, legumes, and nuts). Among spices, saffron displayed the highest antioxidant capacity, whereas among dried fruits, prune exhibited the highest value. The TAC values of all the chocolates analyzed were far higher than the other sweet extracts measured. Among cereal products, whole meal buckwheat and wheat bran had the greatest TAC. Among pulses and nuts, broad bean, lentil and walnuts had the highest antioxidant capacity, whereas chickpeas, pine nuts and peanuts were less effective. The contribution of bound phytochemicals to the overall TAC was relevant in cereals as well as in nuts and pulses. The complete TAC database could be utilized to properly investigate the role of dietary antioxidants in disease prevention.
Breakfast cereals are present on the market as different types and, in general, are one of the food categories in which voluntary information, such as nutrition or health claims (NHC) or gluten free ...(GF) declarations, have the largest distribution. The aims of the present study were to compare (i) the nutritional declaration among different types of breakfast cereals, as well as among products with and without NHC or GF declarations; and (ii) the salt and sugar contents with the "Italian shared objectives for the improvement of the nutritional characteristics of food". To this aim, the nutrition declarations of 371 different breakfast cereal items, available in 13 retailers present on the Italian market, were analysed. Data showed an elevated inter-product variability, with cereal bars and muesli having the highest energy, total fat, and saturate contents per 100 g. Limited differences were found comparing products with and without NHC, as well as those with GF declaration. Most of the breakfast cereals were compliant to the shared objectives, although some items with NHC or GF declaration still have sugar or salt contents higher than these objectives. In conclusion, these data suggest that the different characteristics and the regulated information reported on the food label should not be considered as a marker of the overall nutritional quality. Thus, this study supports the importance of reading and understanding the information made on food label.
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•Intact and fractured cells were identified in legumes using optical microscope.•Legumes flour properties were affected by cell wall structure.•Cell wall intactness enhanced color and ...decreased firmness of gluten free bread.•Intact cell walls significantly reduced the starch hydrolysis in gluten free bread.
Cell integrity has recently been recognized being a key factor in modulating nutrients accessibility, but it has not been assessed in the application of legumes flours in complex matrices. In this study, cell wall intactness fractured cells (FC) or intact cells (IC) and particle size significantly influenced the functional properties of legumes flours. Cannellini bean (CB) flour rich in IC was characterized by high water holding capacity and low starch gelatinization enthalpy, which are features appreciated in gluten-free (GF) bread. Regardless of cell structure, adding 20% of CB to a GF bread decreased breadcrumb hardness and increased crust yellowness. Bread made with IC was softer than that with unfractionated flour, FC and 100% rice. Noteworthy, the extent of starch hydrolysis was reduced when IC (≈33%) was used followed by unfractionated flour (≈40%), FC (≈46%) and 100% rice (≈64%). Predominance of IC enabled a natural barrier against amylolytic enzymes.
We wanted to determine the total antioxidant capacity (6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid equivalent antioxidant assay; TEAC) of different species and cultivars (strawberry and ...apple) and to characterize the TEAC among fruits of the same varieties (peach and apricot) but grafted on different rootstocks.
The study was carried out with wild strawberry, six varieties of cultivated strawberry, and five varieties of apple and with apricot and peach grafted on five different rootstocks that are known to induce different plant vigor and fruit qualitative features. The TEAC (considering lipophilic and hydrophilic contributions) was determined for all fruit varieties, and total polyphenol contents were assayed. One-way analysis of variance was used to test differences among fruits and to identify possible correlations of TEAC versus total phenolics.
The following hierarchy of antioxidant activities was found: wild strawberries ≫ cultivated strawberries ≫ kiwifruit = apples = apricots = peaches. Further, differences were found among strawberries with different genotypes and in apricots and peaches grafted from different rootstocks.
These observations suggest the importance of genotype for determining antioxidant potential and phenolic contents. Variety manipulation may be a powerful tool for modifying antioxidant fruit patterns and contents.
Epidemiologic studies have demonstrated an inverse association between consumption of fruits and vegetables and morbidity and mortality from degenerative diseases. The antioxidant content of fruits ...and vegetables may contribute to the protection they offer from disease. Because plant foods contain many different classes and types of antioxidants, knowledge of their total antioxidant capacity (TAC), which is the cumulative capacity of food components to scavenge free radicals, would be useful for epidemiologic purposes. To accomplish this, a variety of foods commonly consumed in Italy, including 34 vegetables, 30 fruits, 34 beverages and 6 vegetable oils, were analyzed using three different assays, i.e., Trolox equivalent antioxidant capacity (TEAC), total radical-trapping antioxidant parameter (TRAP) and ferric reducing-antioxidant power (FRAP). These assays, based on different chemical mechanisms, were selected to take into account the wide variety and range of action of antioxidant compounds present in actual foods. Among vegetables, spinach had the highest antioxidant capacity in the TEAC and FRAP assays followed by peppers, whereas asparagus had the greatest antioxidant capacity in the TRAP assay. Among fruits, the highest antioxidant activities were found in berries (i.e., blackberry, redcurrant and raspberry) regardless of the assay used. Among beverages, coffee had the greatest TAC, regardless of the method of preparation or analysis, followed by citrus juices, which exhibited the highest value among soft beverages. Finally, of the oils, soybean oil had the highest antioxidant capacity, followed by extra virgin olive oil, whereas peanut oil was less effective. Such data, coupled with an appropriate questionnaire to estimate antioxidant intake, will allow the investigation of the relation between dietary antioxidants and oxidative stress-induced diseases.
For several years the physiological effects of coffee have been focused on its caffeine content, disregarding the hundreds of bioactive coffee components, such as polyphenols, melanoidins, ...carbohydrates, diterpenes, etc. These compounds may exert their protection against colorectal cancer (CRC), the third most common cancer worldwide. However, the amount and type of compounds ingested with the beverage may be highly different depending on the variety of coffee used, the roasting degree, the type of brewing method as well as the serving size. In this frame, this paper reviews the mechanisms by which coffee may influence the risk of CRC development focusing on espresso and filtered coffee, as well as on the components that totally or partially reach the colon i.e. polyphenols and dietary fiber, including melanoidins. In particular the effects of coffee on some colon conditions whose deregulation may lead to cancer, namely microbiota composition and lumen reducing environment, were considered. Taken together the discussed studies indicated that, due to their in vivo metabolism and composition, both coffee chlorogenic acids and dietary fiber, including melanoidins, may reduce CRC risk, increasing colon motility and antioxidant status. Further studies should finally assess whether the coffee benefits for colon are driven through a prebiotic effect.
The consumption of wholegrains (WG) is encouraged worldwide, but the lack of a common legal definition of such products leads to an unclear classification and identification on the grocery store ...shelf. In Italy, several products are generally sold as WG, but it cannot be determined if they are made entirely with all WG cereal(s) or if they are partially produced with WG ingredients (PWG). The aims of this study were to (a) survey the number of cereal-based food items formulated with WG, PWG, or refined (RG) present on the Italian market; and (b) analyse the nutritional quality, intended as nutrition facts, of WG products in comparison to PWG and RG. Nutritional information and declarations were retrieved from packs of 3040 products belonging to five different categories: breakfast cereals, biscuits, sweet snacks, bread, and bread substitutes. A descriptive analysis of the products and comparison of energy, macronutrients, fibre and salt among RG, PWG and WG products within each category was performed. In all categories, a major portion of the products did not contain WG ingredients. Results showed that the nutritional quality of RG, PWG, and WG products varied in relation to the product category and that WG inclusion cannot be always considered a marker of the overall nutritional quality of foods. Instead, it is necessary to evaluate the global product characteristics, and it is important to pay attention to differences between WG and PWG products that can be perceived by consumers as equivalent.
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