Microalgae protein digestibility: How to crack open the black box?

Microalgae are booming as a sustainable protein source for human nutrition and animal feed. Nevertheless, certain strains were reported to have robust cell walls limiting protein digestibility. There are several disruption approaches to break down the cell integrity and increase digestive enzyme accessibility. This review's intent is to discuss the digestibility of microalgae proteins in intact cells and after their disruption. In intact single cells, the extent of protein digestibility is chiefly related to cell wall structural properties (differing among strains) as well as digestion method and when added to food or feed protein digestibility changes depending on the matrix's composition. The degree of effectiveness of the disruption method varies among studies, and it is complicated to compare them due to variabilities in digestibility models, strains, disruption method/conditions and their consequent impact on the microalgae cell structure. More exhaustive studies are still required to fill knowledge gaps on the structure of microalgal cell walls and to find efficient and cost-effective disruption technologies to increase proteins availability without hindering their quality.

Micro- and Macroalgae in Meat Products.

Technology in the meat industry is advancing to create healthier and more sustainable food. Incorporating micro- and macroalgae into meat products presents an exciting possibility for the meat sector to develop functional food, given that they serve as excellent natural sources of nutrients and bioactive compounds. This review aims to systematically outline the impact of incorporating whole algae and their extracts into various meat products, examining their effects on quality, physicochemical and functional properties, sensory characteristics, and potential for enhancing shelf life. Adding algae to meat products generally increased pH values, with variations influenced by concentration, type, initial pH, and storage time. The protein content was mainly unaffected, except for Nori and Chlorella. Algae contributed to lower moisture and higher ash content due to dietary fiber. While including algae improved water-holding capacity and decreased cooking loss, it often led to increased hardness and chewiness. Algae and their extracts influenced color attributes, with variations based on the algae type. Sensory properties were distinctively affected, generally reducing overall acceptability, although Sea tangle at concentrations of 1-3% showed acceptable scores. Chlorella and Sea tangle positively impacted microbiology during refrigerated storage, while algae and their extracts demonstrated strong antioxidant activity.

Influence of different storage atmospheres in packaging on color stability of beef.

The influence of storage atmosphere on the color development and myoglobin (Mb) redox state of beef was investigated. Beef samples were packaged in 6 different atmospheres including different degrees of vacuum, levels of oxygen, nitrogen, and a mixture with 20% CO2 and stored at 2°C for 14 days. Over this time, color and reflection of the packaged samples were measured. The used method allows quick, easy, and non-invasive measurement of the packaged samples, without using time consuming chemical assays. The method could be implemented in beef production lines, with potential for automatization. The data was used to illustrate the L*a*b* values for insights regarding qualitative color changes. Quantitative color changes were analyzed by calculation of color difference ΔE2000. Additionally, the relative levels of the deoxymyoglobin (DMb), oxymyoglobin (OMb) and metmyoglobin (MMb) were calculated from reflection spectra. The most important findings are: there is a strong correlation (rsp = 0.80 to 0.99 with one exception at rsp = 0.69 (high vacuum), p ≤ 0.05) between a* values and relative OMb levels. Storage atmospheres containing high oxygen concentrations lead to an attractive meat color, but a decreased overall color and Mb stability (ΔE = 5.02 (synthetic air) and ΔE = 2.23 (high oxygen) after 14 days of storage). Vacuum packaged samples are most stable in regards of color and Mb stability (ΔE = 1.79 (high vacuum) and ΔE = 1.63 (low vacuum) after 14 days of storage), but lack in the vibrant red color desired for sale. The experiments showed that color measurement can be a fast, non-invasive marker for meat quality. PRACTICAL APPLICATION: In this research article, six different storage atmospheres are compared regarding their influence on color stability and color quality of beef during storage in packaging. The results suggest which atmospheres to use in various sales-related scenarios. The method described can easily be applied in the meat industry to quickly monitor changes during storage and wet-aging without damaging the meat or opening the meat packages.

Confronting Views of Companies and Authorities on Food Safety Issues-A Cross-Country Survey.

This study investigated food safety issues as perceived by food companies and food safety authorities in six countries in Europe and Central Asia. A total of 66 companies and 16 authorities participated in the survey. The results provide important insights related to what the main food safety priorities are, how they are addressed in the countries that participated in the survey, and what the role of the main stakeholders is in the food value chain. Almost 50% of food companies identified 'food fraud' as the most influential food safety attribute. One-third of food safety authorities recognized 'food safety management system' as the most influential food safety attribute. Principal component analysis separated food safety statements into two dimensions named 'food safety hazards and risks' and 'food safety system'. Although there are slight differences in food safety statements between the two stakeholders, i.e., food companies and food safety authorities, it is the country of origin that plays a more important role in understanding their views. Food companies will need to implement a systemic approach and transform the entire food value chain continuum while considering new food safety challenges. It is expected that food safety authorities will have to play a more proactive role in the future.