Microbiological quality of seasoned roasted laver and potential hazard control in a real processing line

Dairy, Plant, and Novel Proteins: Scientific and Technological Aspects

Alternative proteins have gained popularity as consumers look for foods that are healthy, nutritious, and sustainable. Plant proteins, precision fermentation-derived proteins, cell-cultured proteins, algal proteins, and mycoproteins are the major types of alternative proteins that have emerged in recent years. This review addresses the major alternative-protein categories and reviews their definitions, current market statuses, production methods, and regulations in different countries, safety assessments, nutrition statuses, functionalities and applications, and, finally, sensory properties and consumer perception. Knowledge relative to traditional dairy proteins is also addressed. Opportunities and challenges associated with these proteins are also discussed. Future research directions are proposed to better understand these technologies and to develop consumer-acceptable final products.

The complete mitochondrial genome of Neoporphyra dentata (Bangiales, Rhodophyta)

Neoporphyra dentata (Kjellman) L.-E. Yang & J. Brodie, 2020 is an economically valuable species in seaweed aquaculture in the southwest coastal regions of Korea. Here, we report the complete mitogenome information of N. dentata using Illumina Miseq platform permitted assembly of a circular mitochondrial genome of 26,807 bp from N. dentata consisting of 29.9% GC contents, 9 protein coding genes (PCGs), 2 ribosomal RNA genes (12S rRNA and 16S rRNA), 23 transfer RNA (tRNA) genes, and a non-coding region. The overall nucleotide composition was A: 38%, T: 32%, C: 14.7%, and G: 15.2%. The mitochondrial genome of N. dentata contributes to revealing the phylogenetic relationships among species of the Bangiaceae family.

Microbiological Food Safety of Seaweeds

The use of seaweeds in the human diet has a long history in Asia and has now been increasing also in the western world. Concurrent with this trend, there is a corresponding increase in cultivation and harvesting for commercial production. Edible seaweed is a heterogenous product category including species within the green, red, and brown macroalgae. Moreover, the species are utilized on their own or in combinatorial food products, eaten fresh or processed by a variety of technologies. The present review summarizes available literature with respect to microbiological food safety and quality of seaweed food products, including processing and other factors controlling these parameters, and emerging trends to improve on the safety, utilization, quality, and storability of seaweeds. The over- or misuse of antimicrobials and the concurrent development of antimicrobial resistance (AMR) in bacteria is a current worldwide health concern. The role of seaweeds in the development of AMR and the spread of antimicrobial resistance genes is an underexplored field of research and is discussed in that context. Legislation and guidelines relevant to edible seaweed are also discussed.

Seaweeds as a “Palatable” Challenge between Innovation and Sustainability: A Systematic Review of Food Safety

Moderate or severe food insecurity affect 2 billion people worldwide. The four pillars of food security (availability, access, use and stability) are in danger due to the impact of climatic and anthropogenic factors which impact on the food system. Novel foods, like seaweeds, have the potential to increase food yields so that to contribute in preventing or avoiding future global food shortages. The purpose of this systematic review was to assess microbiological, chemical, physical, and allergenic risks associated with seaweed consumption. Four research strings have been used to search for these risks. Preferred Reporting Item for Systematic Reviews and Meta-analysis (PRISMA) guidelines were applied. Finally, 39 articles met the selected criteria. No significant hazards for microbiological, allergenic, and physical risks were detected. Regarding chemical risk, algae can accumulate various heavy metals, especially when harvested in polluted sites. Cultivating seaweeds in a controlled environment allows to avoid this risk. Periodic checks will be necessary on the finished products to monitor heavy metals levels. Since the consumption of algae seems to be on the rise everywhere, it seems to be urgent that food control authorities establish the safety levels to which eating algae does not represent any risk for human health.

Health Functionality and Quality Control of Laver (Porphyra, Pyropia): Current Issues and Future Perspectives as an Edible Seaweed

The growing interest in laver as a food product and as a source of substances beneficial to health has led to global consumer demand for laver produced in a limited area of northeastern Asia. Here we review research into the benefits of laver consumption and discuss future perspectives on the improvement of laver product quality. Variation in nutritional/functional values among product types (raw and processed (dried, roasted, or seasoned) laver) makes product-specific nutritional analysis a prerequisite for accurate prediction of health benefits. The effects of drying, roasting, and seasoning on the contents of both beneficial and harmful substances highlight the importance of managing laver processing conditions. Most research into health benefits has focused on substances present at high concentrations in laver (porphyran, Vitamin B12, taurine), with assessment of the expected effects of laver consumption. Mitigation of chemical/microbiological risks and the adoption of novel technologies to exploit under-reported biochemical characteristics of lavers are suggested as key strategies for the further improvement of laver product quality. Comprehensive analysis of the literature regarding laver as a food product and as a source of biomedical compounds highlights the possibilities and challenges for application of laver products.

Factors Affecting Microbiological Quality of Vegetable- and Meat-Based Meals Served at Cafeterias in the Republic of Korea

A total of 364 samples of vegetable- and meat-based meals were collected at three processing steps: step I, preparation of raw ingredients; step II, processing and cooking; and step III, finished meals. Microbiological quality was evaluated by using data for the prevalence and concentration of the aerobic plate counts, total coliforms (TC), fecal coliforms (FC), and Escherichia coli. The data were analyzed for differences between cafeterias, seasons, raw materials, and processing steps. Fourteen (15.2%) of the 92 finished meal samples were microbiologically unsatisfactory. Neither cafeteria nor season was significantly associated with microbiological quality ( P > 0.05). However, the type of raw ingredients and processing steps were significantly associated with differences in microbiological quality. Vegetable-based meals had higher TC concentrations than meat-based meals because salad and seasoned and fermented vegetables are not cooked, unlike heat-processed meat products. Microbial counts tended to decrease through the processing steps, and E. coli, which could only be enumerated on uncooked chicken breast (1.6 log CFU/g) and sliced pork (2.6 log CFU/g), was totally eliminated by boiling and roasting. However, the presence of FC was not completely eliminated, even by cooking, and so this group of organisms should be considered as an important indicator of hygienic meal preparation in cafeterias. Although pathogenic E. coli was not isolated in this study, continuous microbiological monitoring of composite foods served in cafeterias should be performed as the presence of TC and FC in finished meals indicates the potential for contamination by pathogenic E. coli.

Changes in microbial composition and the prevalence of foodborne pathogens in crab marinated in soy sauce produced by six manufacturing plants

BACKGROUND

The present study examined the changes in microbiological composition during the production process of crab marinated in soy sauce, potential microbial hazards, potential contamination routes and effective critical control points. Crab and soy sauce samples were obtained from six different manufacturing plants at different stages, and their microbiological content was comprehensively assessed by quantitative and qualitative analyses.

RESULTS

The results revealed the following: (1) the final products contained 4.0 log colony-forming units (CFU) g^-1 aerobic plate counts (APCs) and 1.1 log CFU g^-1 coliforms, which may have been introduced from the raw materials (the level of APCs in raw crab and soy sauce mixed with other ingredients was 3.8 log CFU g^-1 and 4.0 log CFU mL^-1 respectively); (2) marination of crab in soy sauce may allow cross-contamination by coliforms; (3) only Bacillus cereus and Staphylococcus aureus were qualitatively detected in samples at different stages of manufacture (detection rate of 28 and 5.6% respectively), and these bacteria may impact the microbiological quality and safety of crab marinated in soy sauce; and (4) bacterial counts were either maintained or increased during the manufacturing process (suggesting that no particular step can be targeted to reduce bacterial counts).

CONCLUSION

Proper management of raw materials and the marination process are effective critical control points, and alternative interventions may be needed to control bacterial quantity. The results provide important basic information about the production of crab marinated in soy sauce and may facilitate effective implementation of sanitary management practices in related industries and research fields. © 2016 Society of Chemical Industry.

Raw ready-to-eat seafood safety: microbiological quality of the various seafood species available in fishery, hyper and online markets

Microbiological quality of 206 raw ready-to-eat seafood samples was investigated according to species (gizzard shad, halibut, rockfish, tuna, oyster and squid) and distribution channels (fishery, hyper and online market). Enumeration of aerobic plate count and total coliforms (TC) and pathogenic bacteria (Bacillus cereus, Staphylococcus aureus and Vibrio parahaemolyticus) was performed, and level of microbiological quality was classified into four groups: satisfactory, acceptable, unsatisfactory and unacceptable. Qualitative analysis was also performed for Escherichia coli and eight foodborne pathogens (B. cereus, E. coli O157:H7, Listeria monocytogenes, Salmonella spp., S. aureus, Vibrio cholerae, V. parahaemolyticus, and Vibrio vulnificus). Raw ready-to-eat seafood products revealed 0·5% at an unsatisfactory level and 4·9% at an unacceptable level due to ≥4 log CFU g^-1 of TC in squid and ≥3 log CFU g^-1 of V. parahaemolyticus in gizzard shad respectively. Gizzard shad was shown to be potentially hazardous, as its sashimi is eaten with its skin attached. Bacillus cereus, E. coli, S. aureus, V. parahaemolyticus and V. vulnificus were qualitatively detected. Samples from the fishery market showed higher detection rate especially in V. parahaemolyticus (21·6%) and V. vulnificus (1·7%) which indicates the need to improve microbiological safety of raw ready-to-eat seafood products in fishery market.

SIGNIFICANCE AND IMPACT OF THE STUDY

Raw ready-to-eat seafood products like sashimi can be easily contaminated with various bacteria from aquatic environments and human reservoirs, which subsequently bring about a risk in food poisoning due to no heating process before consumption. The results of this study provide comprehensive microbiological data on various species of raw ready-to-eat seafood from various distribution channels. It may contribute to establish reasonable standard and effective strategies to ensure a good microbiological quality of raw ready-to-eat seafood for the safety of meals, like sashimi and sushi.

Inactivation of Bacillus cereus spores in a tsuyu sauce using continuous ohmic heating with five sequential elbow-type electrodes

AIMS

The effect of ohmic heating (OH) in a pilot plant system which had a zig-zag shaped (elbow-type) ohmic heater with five sequential voltage electrodes was investigated on Bacillus cereus spores in a commercial tsuyu sauce.

METHODS AND RESULTS

The electrical field was fixed at 26·7 V cm(-1) with an alternating current frequency of 25 kHz. Raw tsuyu sauce (50 l) inoculated with B. cereus spores was submitted in a 4 × 3 factorial design to the OH system and heated at 95, 105, 115, and 125°C each for 30, 60, and 90 s. Survival of B. cereus spores and colour change in the commercial tsuyu sauce were both measured before and after treatment. As the treatment temperature and time increased, the number of surviving B. cereus spores decreased. The OH treatment in a bath-type process at 105°C for more than 30 s resulted in the total inactivation of the inoculated B. cereus spores (average 5·4 log reductions to undetectable levels after treatment). The OH protocol of heating at 105°C for 60 s which ensure complete eradication of the inoculated spores without compromising product quality was chosen and investigated for its suitability for commercial application on bulk quantities of samples (500 l). Reliable and reproducible reductions in B. cereus spore counts of 4·7-5·5 log CFU ml(-1) (mean ± standard deviation = 5·1 ± 0·3 CFU ml(-1) ) were achieved by the selected protocol of the continuous OH treatment (105°C for 60 s).

CONCLUSION

This study suggests that OH treatment with five sequential elbow-type electrodes has great potential as an industrial sterilizing method for liquid food contaminated with B. cereus spores.

SIGNIFICANCE AND IMPACT OF THE STUDY

This procedure will enhance the microbiological quality of liquid foods while minimizing quality deterioration.