Potential prebiotic effect of a long-chain dextran produced by Weissella cibaria: an in vitro evaluation.

Dextrans are homopolysaccharides of D-glucose units produced by lactic acid bacteria. They have several technological applications and potential utilisation in positively modulating gut microbiota is attracting increasing attention. Whereas the prebiotic activity of low polymerisation degree (DP) dextrans has been established, high DP dextrans still deserve deeper investigation. In the present study, a long linear chain dextran produced by Weissella cibaria was compared to inulin with regards to the growth of specific health-related taxa and to the production of organic acids in pH-controlled batch cultures of intestinal microbiota. qPCR quantification of Lactobacillus, Bifidobacterium, Prevotella, Bacteroides fragilis, and Faecalibacterium prausnitzii revealed differences in their relative abundance, depending on the carbon source, that reflected the pattern of fermentation products determined by HPLC. Dextran mainly enhanced the relative amount of Prevotella and Bacteroides, consistently with a favourable acetate-propionate ratio suggesting a promising utilisation as functional ingredient in the food industry.

Effect of sprouting on nutritional quality of pulses.

In order to investigate the nutritional quality of industrial-scale sprouted versus unsprouted chickpeas and green peas, before and after cooking, the ultrastructure, chemical composition, antioxidant capacity, starch digestibility, mineral content and accessibility were analysed. Sprouting did not deeply affect raw seed structure, although after cooking starch granules appeared more porous and swelled. Chemical composition of raw sprouted seeds was not strongly affected, excepting an increase in protein (both pulses), and in free sugars (in peas; +10% and +80%, respectively, p < .05). The industrial sprouting favoured phytic acid leaching in cooking water (-35% in seeds, compared to unsprouted cooked ones, p < .05), and promoted antioxidant capacity reductions in raw and cooked seeds (-10% and -37%, respectively, p < .05). In conclusion, sprouting on an industrial-scale induced mild structural modifications in chickpeas and peas, sufficient to reduce antinutritional factors, without strongly influencing their nutritional quality. These products could represent nutritionally interesting ingredients for different dietary patterns as well as for enriched cereal-based foods.

Designing a Score-Based Method for the Evaluation of the Nutritional Quality of the Gluten-Free Bakery Products and their Gluten-Containing Counterparts.

Gluten-free (GF) products are consumed both by individuals with celiac disease and by an increasing number of people with no specific medical needs. Although the technological quality of GF products has been recently improved, their nutritional quality is still scarcely addressed. Moreover, the few published studies report conflicting results, mostly because the information from product nutrition facts is the only considered factor. The aim of the present study was to develop a score-based method for the nutritional evaluation of 134 packaged Italian GF bakery products and to compare it with that of 162 matched gluten-containing (GC) food items. The score included the information from the nutrition facts and the presence/absence of some nutritionally relevant components in the ingredients list. Results indicated an overall low nutritional quality of the considered GF bakery products. Additionally, with the sole exception of GF bread substitutes, there was no difference in nutritional quality between GF and equivalent GC bakery products. Future research and development of GF bakery products may take advantage of this scoring method, as it may represent an easy approach to evaluate their nutritional quality. The present findings do not justify the consumption of packaged GF bakery products by people without any specific medical needs.

The Update of the Italian Food Composition Database of Gluten-Free Products and Its Application in Food-Based Dietary Guidelines Menus.

Complete food composition databases (FCDBs) on gluten-free (GF) foods are needed to assess the nutrient intakes of celiac disease patients. The aim of the present work was to update the previously developed version of the Italian GF-FCDB and to apply it to a theoretical GF diet. The updated GF-FCDB includes the composition of 108 GF cereal-based foods, as sold, in terms of energy and macro- and micro-nutrients, imputed using food label information combined with the standard recipe approach. Three scenarios (i.e., refined, mixed, and wholegrain cereals) of the weekly guideline menu for the general Italian population were analyzed for energy and nutrient content in a theoretical dietary assessment using traditional gluten-containing (GC) foods and the corresponding GF substitutes. All GF menus were higher than the corresponding GC menus in polyunsaturated fatty acids, linoleic acid, and vitamin E. Zinc was lower in GF than in GC menus only in the wholegrain-cereal scenario. Thanks to the application of the updated GF-FCDB including a comprehensive list of micronutrients, we observed that it is possible for celiac disease patients to meet nutrient requirements by simply substituting GC with GF cereal-based products following recommendations for the general population.

Inulin enrichment of gluten free breads: Interaction between inulin and yeast.

Inulin can improve the nutritional quality of gluten free (GF) bread and have a prebiotic activity. However, breadmaking might frustrate the enrichments efforts due to inulin loss. In this study we aimed at studying the inulin enrichment of GF bread. Two different yeasts [having normal (Y1) or reduced (Y2) invertase activity] were used to leaven the breads enriched with five marketed inulins, which differed for the degree of polymerization (DP) and the manufacturer. Inulin replaced 10% of the rice flour and had low, intermediate or high DP, which ranged from 2 to 20; ≈20; ≥20, respectively. Fructan hydrolysis occurred during leavening of Y1-GF breads, reaching losses up to 40% after baking, depending on the diverse DP of the inulin-forming fructans. Inulin loss was less relevant in Y2-GF breads (up to 5% after baking) than Y1-GF breads. Crumb texture was not negatively influenced by inulin presence, even if this was high (e.g., Y2-GF breads). Information collected within this study may provide further insight to better optimize a GF bread formulation in view of inulin enrichment.

A Retrospective Study on Dietary FODMAP Intake in Celiac Patients Following a Gluten-Free Diet.

Our aim was to evaluate the intake of foods containing fermentable oligo/di/mono-saccharides and polyols (FODMAP) as a possible factor that induces gastrointestinal symptoms in treated celiac disease (CD) patients. We collected seven-day weighed food records for 104 CD patients and 91 healthy volunteers. All evaluated food items were from sources with high and low content of FODMAP, which were divided into cereals and sweets, sweeteners and soft drinks, fruits, dried fruits, and vegetables. Nutrient intake was calculated using the food database of the European Institute of Oncology. The symptoms reported were assessed by a Rome IV Irritable bowel syndrome (IBS) diagnostic questionnaire and by specific questions for the evaluation of functional gastrointestinal disorders (FGIDs). The 12% of CD patients met IBS symptoms criteria as opposed to 6% of controls (p = 0.09) and 27% of patients reported FGIDs symptoms vs. 22% of healthy controls (p = 0.42). The intake by CD patients was significantly higher than healthy volunteers for: sweeteners and sugars with low content of FODMAP (p = 0.0007), fruits, dried fruits, and vegetables high in FODMAP (p = 0.003) and low in FODMAP (p = 0.04) when compared to controls. CD patients had a lower intake of cereals and sweets with a high content of FODMAP (p = 0.00001). Healthy volunteers consumed significantly higher alcoholic beverages and fats high in FODMAP (both p < 0.044). The mean daily intake of other food categories did not differ between both groups. Even though CD patients had a low intake of gluten-free cereals high in FODMAP, they still consumed a significant amount of fruits and vegetables high in FODMAP. The clinical effect of a concomitant gluten-free diet and low-FODMAP diet should be prospectively evaluated as a supportive therapy in CD patients.

Gluten-free pasta incorporating chia (Salvia hispanica L.) as thickening agent: An approach to naturally improve the nutritional profile and the in vitro carbohydrate digestibility.

A gluten-free pasta was prepared adding chia at rice flour for testing the thickening and nutritional properties of this specie. Chemical analysis showed chia is a source of protein (19.52% and 15.81%, seeds and mucilage respectively), insoluble/soluble dietary fiber ratio (4.3 and 1.79 seeds and mucilage respectively), fat and ash content. The total phenolic acids content ranged from 734.5µg/g to 923.9µg/g for seeds and mucilage respectively. Chia was a good thickening agent and, improved the nutritional profile of enriched samples compared to CGF. After cooking TPAs increased in all samples, ranging from 5.3% in DW to 52.8% in CM5. The addition of chia seeds also increased the slowly digestible starch fraction of rice flour, commonly known to have a high glycemic index. Results suggest that chia should be added as thickening agent in the formulation of GF pasta for conferring healthier characteristics.