The effect of carrageenan and gelatine hydrosols incorporated with acidic electrolysed water on surface microbiota and quality changes on pork meat

Physicochemical and microbiological evaluation of treated Gastrodia elata with combination of slightly acidic electrolyzed water and lithium magnesium silicate under certain temperatures and different storage periods

This study aimed to investigate the impact of slightly acidic electrolyzed water combined with lithium magnesium silicate hydrosol on the quality of fresh slices of Gastrodia elata under varying storage temperatures, including room temperature fresh slices of Gastrodia elata 25 °C and 37 °C. Fresh slices of Gastrodia elata 25 and 37 samples were stored for 13 days and extensively analyzed for color, weight loss, decay index, bacterial count, vitamin C, and polysaccharide contents during different storage periods. The findings revealed that the slightly acidic electrolyzed water + hydrosol treatment notably decreased weight loss and decay index compared to distilled water and slightly acidic electrolyzed water treatments. Moreover, fresh slices of Gastrodia elata treated with slightly acidic electrolyzed water  + hydrosol exhibited untraceable bacterial counts after 3 days, with counts starting to increase after 7 days of storage. The bacterial counts rose from 3.25 to 5.36 and from 4.13 to 5.79 log CFU/g under both storage conditions. The application of slightly acidic electrolyzed water + hydrosol resulted in reduced chromaticity values of L*, a*, and b* on the Gastrodia elata surface, along with a lower percentage loss of polysaccharide contents and vitamin C compared to distilled water and slightly acidic electrolyzed water treatments. These results suggested that Gastrodia elata treated with slightly acidic electrolyzed water + hydrosol maintained its quality characteristics and nutritional attributes, exhibiting greater stability during storage.

Characterization and Application of Gelatin Films with Pecan Walnut and Shell Extract (Carya illinoiensis)

Phenolic compounds that come from natural products are a good option for minimizing lipid oxidation. It should be noted that these are not only introduced directly into the food, but also incorporated into edible biofilms. In contact with food, they extend its useful life by avoiding contact with other surface and preventing deterioration air, one of the main objectives. In particular, gelatin is a biopolymer that has a great potential due to its abundance, low cost and good film-forming capacity. The aim of this study has been to design and analyse gelatin films that incorporate bioactive compounds that come from the walnut and a by-product, the walnut shell. The results showed that mechanical and water vapor barrier properties of the developed films varied depending on the concentration of the walnut, shell and synthetic antioxidant. With increasing walnut concentration (15%) the permeability to water vapor (0.414 g·mm/m2·day·Pascal, g·mm/m2·day·Pa) was significantly lower than the control (5.0368 g·mm/m2·day·Pa). Furthermore, in the new films the elongation at the break and Young's modulus decrease by six times with respect to the control. Films with pure gelatin cannot act as an antioxidant shield to prevent food oxidation, but adding pecan walnut (15% concentration) presents 30% inhibition of the DPPH stable radical. Furthermore, in the DSC, the addition of walnut (15 and 9% concentrations), showed the formation of big crystals; which could improve the thermal stability of gelatin films. The use of new gelatin films has shown good protection against the oxidation of beef patties, increasing the useful lifetime up to nine days, compared to the control (3-4 days), which opens up a big field to the commercialization of meat products with lower quantities of synthetic products.

Functionalization of water as a nonthermal approach for ensuring safety and quality of meat and seafood products

Meat and seafood products present a viable medium for microbial propagation, which contributes to foodborne illnesses and quality losses. The development of novel and effective techniques for microbial decontamination is therefore vital to the food industry. Water presents a unique advantage for large-scale applications, which can be functionalized to inactivate microbial growth, ensuring the safety and quality of meat and seafood products. By taking into account the increased popularity of functionalized water utilization through electrolysis, ozonation and cold plasma technology, relevant literature regarding their applications in meat and seafood safety and quality are reviewed. In addition, the principles of generating functionalized water are presented, and the safety issues associated with their uses are also discussed.Functionalization of water is a promising approach for the microbiological safety and quality of meat and seafood products and possesses synergistic effects when combined with other decontamination approaches. However, functionalized water is often misused since the active antimicrobial component is applied at a much higher concentration, despite the availability of applicable regulations. Functionalized water also shows reduced antimicrobial efficiency and may produce disinfection by-products (DBPs) in the presence of organic matter, especially at a higher concentration of active microbial component. Utilization should be encouraged within regulated guidelines, especially as hurdle technology, while plasma functionalized water which emerges with great potentials should be exploited for future applications. It is hoped that this review should encourage the industry to adopt the functionalized water as an effective alternative technique for the food industry.

The Effects of Using Sodium Alginate Hydrosols Treated with Direct Electric Current as Coatings for Sausages

We investigated the effect of sodium alginate hydrosols (1%) with 0.2% of NaCl treated with direct electric current (DC) used as a coating on microbial (Total Viable Counts, Psychrotrophic bacteria, yeast and molds, Lactic acid bacteria, Enterobacteriaceae), physiochemical (pH, lipid oxidation, antioxidant activity, weight loss, color) and sensory properties of skinned pork sausages or with artificial casing stored at 4 °C for 28 days. Moreover, the cytotoxicity analysis of sodium alginate hydrogels was performed. The results have shown that application of experimental coatings on the sausage surface resulted in reducing all tested groups of microorganisms compared to control after a 4-week storage. The cytotoxicity analysis revealed that proliferation of RAW 264.7 and L929 is not inhibited by the samples treated with 200 mA. Ferric reducing antioxidant power (FRAP) and free radical scavenging activity (DPPH) analyses showed that there are no significant differences in antioxidant properties between control samples and those covered with sodium alginate. After 28 days of storage, the highest value of thiobarbituric acid-reactive substances (TBARS) was noticed for variants treated with 400 mA (1.07 mg malondialdehyde/kg), while it was only slightly lower for the control sample (0.95 mg MDA/kg). The obtained results suggest that sodium alginate treated with DC may be used as a coating for food preservation because of its antimicrobial activity and lack of undesirable impact on the quality factors of sausages.