Total phenolic contents, antioxidant and antibacterial activities of chia seeds (Salvia hispanica L.) having different coat color

Improving the microbial quality and sensory properties of pasteurized sweet cream butter during refrigerated storage using chia seed ethanolic extract

Butter is a perishable food, and its microbial deterioration occurs in refrigeration conditions, leading to a reduction in shelf life and a loss of sensory properties. This study aimed to investigate the effect of chia seed extract (CSE) on the microbial and sensory properties of pasteurized sweet cream butter at 2°C. Ethanolic extract of chia seeds was prepared and added to the butter samples in concentrations of 0.05%, 0.1%, 0.25%, and 0.5% (v/w), and its effects on microbiological and sensory quality were evaluated at 15-day intervals during 60-day refrigerated storage. The results indicated that the addition of 0.25% and 0.5% CSE to butter treatments decreased total viable counts by 0.25-0.6 log CFU/g, total psychrotrophic counts by 1-1.5 log CFU/g, and coliform counts by 3-4 log CFU/g compared to the control sample on days 45 and 60 of storage. Moreover, concentrations of 0.1%-0.5% CSE reduced mold and yeast counts by 1.5-2.6 log CFU/g on days 30-60 of storage compared to the control sample. Escherichia coli and Staphylococcus aureus were not detected in any samples during storage. CSE had a significant effect on the sensory properties (except for aroma) of the butter samples during the 60-day storage. The best color, flavor, and overall acceptance scores were assigned to the treatments containing 0.1%-0.5% CSE compared to the control sample. It could be concluded that adding 0.1% and 0.25% CSE to refrigerated and pasteurized butter can retard microbial spoilage and improve its sensory properties at the same time.

Comparative Analysis of Metabolic Variations, Antioxidant Profiles and Antimicrobial Activity of Salvia hispanica (Chia) Seed, Sprout, Leaf, Flower, Root and Herb Extracts

The purpose of this study was to evaluate the phytochemical profiles of the seeds, sprouts, leaves, flowers, roots and herb of Salvia hispanica and to demonstrate their significant contribution to antioxidant and antimicrobial activities. Applied methods were: HPLC-DAD coupled with post-column derivatization with ABTS reagent, untargeted metabolomics performed by LC-Q-Orbitrap HRMS, and two-fold micro-dilution broth method, which involved suspending a solution of tested compounds dissolved in DMSO in Mueller–Hinton broth for bacteria or Mueller–Hinton broth with 2% glucose for fungi. Metabolomic profiling using LC-Q-Orbitrap HRMS used in this study yielded the identification and preliminary characterization of one hundred fifteen compounds. The dominant class of compounds was terpenoids (31 compounds), followed by flavonoids (21 compounds), phenolic acids and derivatives (19 compounds), organic acids (16 compounds) and others (fatty acids, sugars and unidentified compounds). The organic and phenolic acids were the most abundant classes in terms of total peak area, with distribution depending on the plant raw materials obtained from S. hispanica. The main compound among this class for all types of extracts was rosmarinic acid which was proven to be the most abundant for antioxidant potential. All tested extracts exhibited considerable antibacterial and antifungal activity. The strongest bioactivity was found in leaf extracts, which presented bactericidal activity against Gram-positive bacteria (S. aureus, S. epidermidis, M. luteus and E. faecalis). The work represents the first compendium of knowledge comparing different S. hispanica plant raw materials in terms of the profile of biologically active metabolites and their contribution to antioxidant, antimicrobial and antifungal activity.

A new approach to nanocomposite carbohydrate polymer films: Levan and chia seed mucilage

Plastic pollution is increasing day by day and the search for new, environmentally friendly products continues. Herein, for the first time, different degrees of mucilage were obtained from chia seeds and the film-forming behavior of levan biopolymer with these mucilages was investigated. Glycerol and sorbitol were used as plasticizers in the film design. Films prepared with sorbitol were characterized physically, mechanically and morphologically. The antioxidant and antimicrobial effects of the films were examined. The films formed as nanocomposites of levan and chia seed mucilages obtained at different temperatures (25 °C, 55 °C and 80 °C) exhibited structurally and mechanically different properties. It was observed that the films obtained with chia mucilages and levan preserved their antibacterial properties but lost their antifungal properties. In addition, quorum sensing property of the mucilage obtained at 55 °C during the investigation of the antibacterial property was reported for the first time with this study. The levan-based chia seed mucilages films obtained have the potential to be used in industrial and medical fields, and the nature-friendly nature of these films is very important for our green world.

Thermal Inactivation Kinetics of Salmonella and Enterococcus faecium NRRL-B2354 on Whole Chia Seeds (Salvia hispanica L.)

ABSTRACT

Intervention technologies for inactivating Salmonella on whole chia seeds are currently limited. Determination of the thermal inactivation kinetics of Salmonella on chia seeds and selection of an appropriate nonpathogenic surrogate will provide a foundation for selecting and optimizing thermal pasteurization processes for chia seeds. In this study, chia seed samples from three separate production lots were inoculated with a five-strain Salmonella cocktail or Enterococcus faecium NRRL-B2354 and equilibrated to a water activity of 0.53 at room temperature (25°C). After equilibration for at least 3 days, the inoculated seeds were subjected to isothermal treatments at 80, 85, or 90°C. Samples were removed at six time points, and surviving bacteria were enumerated. Whole chia seeds were diluted in a filter bag at 1:30 because bacterial recovery with this method was similar to that obtained from ground seeds. Survivor data were fitted to consolidated models: one primary model (log linear or Weibull) and one secondary model (Bigelow). E. faecium had higher thermal resistance than did Salmonella, suggesting that E. faecium may be a suitable conservative nonpathogenic surrogate for Salmonella. The Weibull model was a better fit for the survivor data than was the log-linear model for both bacteria based on the lower root mean square error and corrected Akaike's information criterion values. Lipid oxidation measurements and fatty acid concentrations were significantly different from those of the control samples, but the overall magnitude of the differences was relatively small. The thermal inactivation kinetics of Salmonella and E. faecium on chia seeds may be used as a basis for developing thermal pasteurization processes for chia seeds.

HIGHLIGHTS

Chia, Quinoa, and Their Coproducts as Potential Antioxidants for the Meat Industry

Chia and quinoa have gained popularity among consumers worldwide due to the wide variety of nutrients but also to the bioactive compounds that they contain. Lately, their processing has generated different coproducts (non-commercial grains, flour, partially deoiled flour, rich-fiber fraction, and oil, among others), which could be reincorporated to the food chain with important technological properties, antioxidant activity included. Both sets of ingredients have been revealed a great technological potential for meat product development and innovation, taking into account that oxidation is one of the main reactions responsible for their deterioration and shelf life reduction. This review focuses on the antioxidant compounds of chia and quinoa coproducts and on the strategies used to add them to meat products highlighting their effect on the lipid oxidation control. Apart from the different ways in which quinoa and chia can be incorporated into meat products and their antioxidant properties, innovative approaches for increasing this antioxidant effect and counteracting any negative alterations they may cause will be discussed.