Emerging techniques applied to by-products for food fortification.

Considering the increasing consumer demand for healthy food, the extract from broccoli by-products was studied. To this aim, in the first step, three extraction techniques were compared in terms of extraction efficiency. The best method was the pressurized liquid extraction. Then, the extract microencapsulation was optimized in terms of type of wall material (between Capsul and maltodextrins), concentration of wall material (10-20-30%, w/v), core/wall material ratio (1:2, 1:5, 1:10, 1:20) and inlet temperature (80, 100, 130, 150, 170 °C). The optimal conditions were found with 10% maltodextrins as wall material, core/wall material ratio 1/2 at 80 °C. Finally, the obtained microencapsulated extract was added at 5% (w/w) to fish burgers. Results demonstrated that total phenolic content, total flavonoids and antioxidant activity of enriched fish products were significantly higher than the control burgers, thus confirming that both process and cooking did not greatly affect the nutritional properties of extracted compounds.

Extract from Broccoli Byproducts to Increase Fresh Filled Pasta Shelf Life.

The aim of the study was to evaluate the efficacy of extract from broccoli byproducts, as a green alternative to chemical preservation strategies for fresh filled pasta. In order to prove its effectiveness, three different percentages (10%, 15%, and 20% v/w) of extract were added to the filling of pasta. A shelf life test was carried out by monitoring microbiological and sensory quality. The content of phenolic compounds before and after in vitro digestion of pasta samples was also recorded. Results underlined that the addition of the natural extract helped to record a final shelf life of about 24 days, that was 18 days longer in respect to the control sample. Furthermore, results highlighted that the addition of byproducts extract to pasta also increased its phenolic content after in vitro digestion. Therefore, broccoli byproducts could be valorized for recording extracts that are able to prolong shelf life and increase the nutritional content of fresh filled pasta.

Lactobacillus plantarum 5BG Survives During Refrigerated Storage Bio-Preserving Packaged Spanish-Style Table Olives (cv. Bella di Cerignola).

This paper proposes bio-preservation as a tool to assure quality and safety of Spanish-style table olives cv. Bella di Cerignola. Lactobacillus plantarum 5BG was inoculated in ready to sell olives packaged in an industrial plant by using a half-volume brine (4% NaCl; 2% sucrose). The samples were stored at 4°C. The survival of the inoculated strain, the microbiological quality, the sensory scores and the survival of a strain of Listeria monocytogenes inoculated in brines were evaluated. The persistence of the Lb. plantarum bio-preserving culture was confirmed on olives (≥6.5 Log CFU/g) and in brine (≥7 Log CFU/ml). Bio-preserved olives (SET1) showed a better sensory profile than chemically acidified control olives (SET2) and the texture was the real discriminative parameter among samples. Bio-preserved olives recorded better scores during storage because of their ability to retain good hardness, crunchiness, and fibrousness without cracks. The inoculation of Lb. plantarum positively acted on the safety of olives, as the D-value of L. monocytogenes was reduced from 40 (SET2) to 5 days (SET1). In conclusion, Lb. plantarum 5BG and the physico-chemical conditions achieved in the settled procedure are suitable for the industrial packaging of Bella di Cerignola table olives, improving the process by halving brining volumes and avoiding chemical stabilizers, and significantly reducing the salt concentration. The final product is also safely preserved for almost 5 months as suggested by the reduction of the survival rate of L. monocytogenes.

Enzyme Crystals and Hydrogel Composite Membranes as New Active Food Packaging Material.

The great antimicrobial and antioxidant potential of enzymes makes them prone to be used as active packaging materials to preserve food from contamination or degradation. Major drawbacks are connected to the use of enzymes freely dispersed in solution, due to reduced protein stability. The immobilization of enzymes on solid supports to create biocatalytic interfaces has instead been proven to increase their stability and efficiency. In this work, it is shown that enzymes crystallized on hydrogel composite membranes (HCMs) can exert an effective antimicrobial action, thus making the composite membrane and crystals biofilm a potential active substrate for food packaging applications. The antimicrobial hen egg white lysozyme is crystallized on the surface of the hydrogel layer of HCMs, and its activity is determined by measuring the decrease in absorbance of Micrococcus lysodeikticus culture incubated with the specimen. The overall catalytic efficiency of the antimicrobial HCMs increases by a factor of 2 compared to the pure enzyme dissolved in solution at the same quantity. Because the enzyme in crystalline form is present in higher concentration and purity than in the solution, both its overall catalytic efficiency and antimicrobial action increase. Moreover, the hydrogel environment allows a better protein stabilization and retention during crystals dissolution.