Quality Evaluation of Fresh Pasta Fortified with Sourdough Containing Wheat Germ and Wholemeal Semolina.

Pasta is a staple food in the Mediterranean diet, primarily manufactured with two essential ingredients, semolina and water; nowadays, it is often supplemented with functional ingredients. In this work, a sourdough obtained with wheat germ and wholemeal semolina was used, in order to improve sensorial and nutritional properties of fresh pasta, to prevent lipids oxidation, and to improve the shelf life. Three different formulations were prepared, a first one using semolina, a second one with raw wheat germ, wholemeal semolina, and semolina, and the last one with semolina and sourdough. The study highlighted the improved nutritional properties of pasta with sourdough (reduced phytic acid content, higher antioxidant activity and phenolic content). Proteins, ashes, dietary fibers, lipids, and tocols (vitamin E) increased in pasta with wheat germ and wholemeal semolina, and with sourdough. The amount of tocols decreased in pasta samples after cooking, except for the ß-tocopherol in sourdough pasta, the amount of which remained high, surprisingly. Lipase and lipoxygenase enzymes likely decreased as an effect of the pasteurization process. The NMR analysis showed that lipid oxidation was higher in semolina pasta than in pasta with wheat germ, most likely due to the protective effect of antioxidants deriving from wheat germ.

In Vivo and In Vitro Starch Digestibility of Fresh Pasta Produced Using Semolina-Based or Wholemeal Semolina-Based Liquid Sourdough.

The use of wholemeal flour and sourdough fermentation in different food matrices has received considerable attention in recent years due to its resulting health benefits. In this study, a semolina-based and a wholemeal semolina-based sourdough were prepared and added to the formulation of gnocchetti-type fresh pasta. Four types of gnocchetti were made, using semolina plus semolina-based sourdough (SS), semolina plus wholemeal semolina-based sourdough (SWS), semolina alone (S), and semolina plus wholemeal semolina (WS). The latter two were used as controls. The digestibility of starch was studied both in vitro and in vivo, and the glycemic response (GR) and glycemic load (GL) were determined. Starch digestibility, both in vivo and in vitro, was higher in wholemeal semolina than semolina pasta and the resulting GR values (mg dL-1 min-1) were also higher (2209 and 2277 for WS and SWS; 1584 and 1553 for S and SS, respectively). The use of sourdough significantly reduced the rapidly digestible starch (RDS) content and increased the inaccessible digestible starch (IDS) content. The addition of sourdough to the formulation had no effect on the GR values, but led to a reduction of the GL of the pasta. These are the first data on the GR and GL of fresh pasta made with sourdough.

Technological, Nutritional and Sensory Properties of an Innovative Gluten-Free Double-Layered Flat Bread Enriched with Amaranth Flour.

Celiac disease is increasing all over the world. In this context, most recent research in this area is addressing and attempting to improve the nutritional value and sensory characteristics of gluten-free (GF) food products and to enhance their technological properties. Here, amaranth flour was studied as a potential healthy ingredient for the development of an innovative GF flat bread. Starting from two different basic formulations (rice flour:corn starch and rice flour:tapioca starch, 50:50), the impact of partially replacing rice flour (6%) and starch (6%) with amaranth on the nutritional characteristics, polyphenol composition, textural, and sensory properties of the resulting GF flat breads was explored. The substitution with amaranth led to detrimental effects on the doughs' viscometric properties, especially in the case of tapioca starch, but significantly improved the doughs' textural properties. All the amaranth-enriched flat breads showed a better color and a significant increase in all polyphenols fractions but lower antioxidant activity. During bread storage for three days, a detrimental effect on both starch retrogradation, toughness, and extensibility properties were observed, especially when tapioca starch was used. Check-all-that-apply (CATA) sensory test results showed that the incorporation of amaranth increased yeast odor and yeast flavor perception and decreased the softness in mouth-only in tapioca-based samples. A better compromise among technological, nutritional, and sensory properties was achieved when amaranth flour was added to the basic rice and corn formulation.

Fresh Pasta Manufactured with Fermented Whole Wheat Semolina: Physicochemical, Sensorial, and Nutritional Properties.

Fresh pasta (SP) was prepared by mixing semolina with liquid sourdough, whole wheat semolina based, and the effects of sourdough inclusion were evaluated against a control sample (CP) prepared using semolina and whole wheat semolina. Physicochemical, nutritional, and sensorial analyses were performed on pasteurized fresh pasta, before and after cooking. The optimum cooking time was not affected by whole wheat sourdough, whereas differences were found in color, firmness, and cooking loss. Changes of in vitro digested starch fractions in SP pasta were affected by a higher cooking loss. Overall, SP samples were characterized by improved nutraceutical features, namely higher content of free essential amino acids and phenolic compounds, lower phytic acid content, and higher antioxidant activity. Sensory analyses (acceptability and check-all-that-apply (CATA) tests) showed significantly higher scores for the SP, and the differences were enhanced when the consumers were informed about the product composition and how it was manufactured. Consumers checked for more positive sensory parameters for the SP than the CP.

Effect of liquid sourdough technology on the pre-biotic, texture, and sensory properties of a crispy flatbread.

The present study compared liquid sourdough technology with baker's yeast leavening when applied to the production of a semolina-based crispy flatbread. Following in vitro starch digestion, the results revealed the sourdough leavened flatbread to contain a lower percentage of rapidly digestible starch (16%), higher amounts of slowly digestible starch (27%) and inaccessible digestible starch (4.1%) compared with the baker's yeast leavened flatbread (20, 20, and 2.4%, respectively), making the former nutritionally healthier. The sourdough leavened bread was crispier, stiffer and more solid, as shown by texture analyses, although Raman spectroscopy revealed no differences in the crystallinity status of starch. The descriptive analyses show that the use of sourdough enhances the positive sensory traits, as rated by the consumer panel scores (6.08 vs. 5.56). In summary, the results indicate that the implementation of sourdough technology in the production of flat crispy breads could confer economic advantages to this product.

Bioconversion of ovine scotta into lactic acid with pure and mixed cultures of lactic acid bacteria.

Scotta is the main by-product in the making of ricotta cheese. It is widely produced in southern Europe and particularly in Italy where it represents a serious environmental pollutant due to its high lactose content. With the aim of evaluating whether scotta bioconversion into lactic acid can be considered as an alternative to its disposal, besides providing it with an added value, here the growth, fermentative performances, and lactic acid productions of pure and mixed cultures of Lactobacillus casei, Lactobacillus helveticus, and Streptococcus thermophilus were evaluated on ovine scotta-based media, without and with the addition of nutritional supplements. The outcomes indicate that ovine scotta can be utilized for the biotechnological production of lactic acid with yields up to 92%, comparable to those obtained on cheese-whey. Indeed, the addition of nutritional supplements generally improves the fermentative performances of lactic acid bacteria leading to about 2 g l(-1) h(-1) of lactic acid. Moreover, the use of mixed cultures for scotta bioconversion reduces the need for nutritional supplements, with no detrimental effects on the productive parameters compared to pure cultures. Finally, by using L. casei and S. thermophilus in pure and mixed cultures, up to 99% optically pure L: -lactic acid can be obtained.

Molecular characterization of lactic acid bacteria from sourdough breads produced in Sardinia (Italy) and multivariate statistical analyses of results.

The objective of this work was to investigate the structure and diversity of lactic acid bacteria (LAB) communities in sourdough used for the production of traditional breads (Carasau, Moddizzosu, Spianata, Zichi) in Sardinia. 16S rDNA sequencing and Randomly Amplified Polymorphic DNA (RAPD-PCR) was applied for the identification and typing of the LAB isolated from 25 samples of sourdoughs. Multivariate statistical techniques were applied to RAPD-PCR pattern to study the biological diversity of sourdough samples. Twelve different species of LAB were identified, and most isolates were classified as facultative heterofermentative lactobacilli. Lactobacillus pentosus dominated the lactic microflora of many samples while Lactobacillus sanfranciscensis was isolated only from a limited number of samples. Although heterofermentative species represented between between 30% and 60% of the isolates in Carasau, Spianata and Zichi sourdoughs, only 2% of the isolates from Moddizzosu sourdoughs were identified as heterofermentative LAB. RAPD-PCR with a single primer followed by cluster analysis did not allow the identification of the isolates at the species level. However, a multidimensional scaling/bootstrapping approach on the RAPD-PCR patterns uncovered the diversity of the LAB communities of LAB showing differences both within and between bread types.