Effect of the Addition of Freeze-Dried Grape Pomace on Fresh Tagliatelle Gluten Network and Relationship to Sensory and Chemical Quality.

The incorporation of 5 and 10% freeze-dried grape pomace powder (GPP) in fresh tagliatelle pasta preparation was evaluated for its effect on chemical composition, gluten protein structure, and sensory properties. The addition of the freeze-dried GPP led to a significant increase (p < 0.05) in polyphenol content in the raw and cooked fortified pasta samples with respect to 100% semolina pasta, although the phenolic content decreased after the cooking process. The opposite phenomenon was observed with the antioxidant activity, which increased significantly (p < 0.05) when switching from raw to cooked pasta samples fortified with GPP. The formation of a proper gluten structure was found in the fortified raw pasta, even if a change in the protein arrangement was shown in the fortified cooked samples, confirmed by a significant reduction (p < 0.05) in both the unextractable polymeric protein percentage (% UPP) and disulfide bond (S-S) formation. These results suggest a possible interaction between the protein sulfhydryl groups (-Cys) and polyphenols of grape pomace during cooking through non-disulfide covalent bonds, which was confirmed by the significant (p < 0.05) decrease in the -SH groups when comparing 100% semolina pasta with fortified pasta sample. Finally, a sensory analysis showed that the highest significant score (p < 0.05) was achieved by the 5% GP-fresh pasta sample.

A proteomic study of "Coppa Piacentina": A typical Italian dry-cured Salami.

Coppa Piacentina is considered a peculiar dry cured salami, since it is manufactured by the entire neck muscles stuffed and matured in natural casings, the same as dry cured ham and fermented dry cured sausages. In this work the proteolysis of external and internal portions was investigated by a proteomic approach and by amino acids analysis. Samples of "Coppa Piacentina" were analyzed at 0 days and after 5 and 8 months of ripening through mono- and two-dimensional gel electrophoresis. Image analysis of 2D electrophoretic maps indicated a more intense enzyme activity on the external part, mainly due to endogenous enzymes. They favored, respectively, myofibrillar or sarcoplasmic proteins at 5 or 8 months of ripening. Free amino acids determination proved that lysine and glutamic acid were the most represented ones, followed by a free amino acids sequence like that of dry cured ham. The peculiarities of "Coppa Piacentina" were characterized by a slow proteolysis, due to sacking and binding of the whole cut of the pork neck.

Improving the Storability of Cod Fish-Burgers According to the Zero-Waste Approach.

This research explored the potential of the zero-waste concept in relation to the storability of fresh food products. In particular, the prickly pear (Opuntia ficus-indica) peel (usually perceived as a by-product) and the pulp were dehydrated, reduced in powder, and used as food additives to slow down the growth of the main spoilage microorganisms of fresh cod fish burgers. The proportion between peel and pulp powder was such as to respect the zero-waste concept. The antibacterial activity of the peel and pulp in proper proportion was first assessed by means of an in vitro test against target microorganisms. Then, the active powder was added at three concentrations (i.e., 2.5 g, 7.5 g, and 12.5 g) to cod fish burgers to assess its effectiveness in slowing down the microbial and sensory quality decay of burgers stored at 4 °C. The results from the in vitro test showed that both the peel and pulp were effective in delaying microbial growth. The subsequent storability test substantially confirmed the in vitro test results. In fact, a significant reduction in growth rate of the main fish spoilage microorganisms (i.e., Pseudomonas spp., psychrotrophic bacteria, and psychrotolerant and heat-labile aerobic bacteria) was observed during 16 days of refrigerated storage. As expected, the antimicrobial effectiveness of powder increased as its concentration increased. Surprisingly, its addition did not affect the sensory quality of fish. Moreover, it was proven that this active powder can improve the fish sensory quality during the storage period.

Sustainable Use of Fruit and Vegetable By-Products to Enhance Food Packaging Performance.

Fruit and vegetable by-products are the most abundant food waste. Industrial processes such as oil, juice, wine or sugar production greatly contribute to this amount. These kinds of residues are generally thrown away in form of leftover and used as feed or composted, but they are a great source of bioactive compounds like polyphenols, vitamins or minerals. The amount of residue with potential utilization after processing has been estimated in millions of tons every year. For this reason, many researchers all around the world are making great efforts to valorize and reuse these valuable resources. Of greatest importance is the by-product potential to enhance the properties of packaging intended for food applications. Therefore, this overview collects the most recent researches dealing with fruit and vegetable by-products used to enhance physical, mechanical, antioxidant and antimicrobial properties of packaging systems. Recent advances on synthetic or bio-based films enriched with by-product components are extensively reviewed, with an emphasis on the role that by-product extracts can play in food packaging materials.