Biocontrol of Pathogen Microorganisms in Ripened Foods of Animal Origin

Ripened foods of animal origin comprise meat products and dairy products, being transformed by the wild microbiota which populates the raw materials, generating highly appreciated products over the world. Together with this beneficial microbiota, both pathogenic and toxigenic microorganisms such as Listeria monocytogenes, Salmonella enterica, Staphylococcus aureus, Clostridium botulinum, Escherichia coli, Candida spp., Penicillium spp. and Aspergillus spp., can contaminate these products and pose a risk for the consumers. Thus, effective strategies to hamper these hazards are required. Additionally, consumer demand for clean label products is increasing. Therefore, the manufacturing sector is seeking new efficient, natural, low-environmental impact and easy to apply strategies to counteract these microorganisms. This review gathers different approaches to maximize food safety and discusses the possibility of their being applied or the necessity of new evidence, mainly for validation in the manufacturing product and its sensory impact, before being implemented as preventative measures in the Hazard Analysis and Critical Control Point programs.

Selection of indigenous starter culture for safety and its effect on reduction of biogenic amine content in Moo som

Objective

The aims of this study were to select one strain of Lactobacillus platarum for a potential indigenous safe starter culture with low level antibiotic resistant and low biogenic amine production and evaluate its effect on biogenic amines reduction in Moo som.

Methods

Three strains of indigenous L. plantarum starter cultures (KL101, KL102 and KL103) were selected on the basis of their safety including antibiotic resistance and decarboxylase activity, and fermentation property as compared with a commercial starter culture (L. plantarum TISIR543). Subsequently, the effect of the selected indigenous safe starter culture on biogenic amines formation during Moo som fermentation was studied.

Results

KL102 and TISIR 543 were susceptible to penicillin G, tetracycline, chloramphenicol, erythromycin, gentamycin, streptomycin, vancomycin, ciprofloxacin and trimethoprim (MIC90 ranging from 0.25 to 4 μg/ml). All strains were negative amino acid-decarboxylase for lysis of biogenic amines in screening medium. For fermentation in Moo som broth, a relatively high maximum growth rate of KL102 and TISIR543 resulted in lower their generation times than other strains (p < 0.05). These strain counts were constant during the end of fermentation. Similarly, KL102 or TISIR543 addition supported increases of lactic acid bacterial count and total acidity in Moo som fermentation. For biogenic amine reduction tyramine, putrescine, histamine and spermine contents in Moo som decreased significantly by the addition KL102 during 1 d of fermentation (p < 0.05). In final product, histamine, spermine and tryptamine contents in Moom-Moo som inoculated with KL102 were lower amount those with TISIR543 (p < 0.05).

Conclusion

The results focused on selection of an indigenous safe starter culture, KL102, for using in production of Moo som and composition of this suitable starter culture to reduce the biogenic amine formation in Moo som.

The Effects of Probiotic Cultures in Functional Foods

Functional foods are an important part of an overall healthy lifestyle that includes a balanced diet and physical activity. The consumption of probiotic foods has many benefits. Dairy products that contain probiotic bacteria are those that are produced with various fermentation methods, especially lactic acid fermentation, by using starter cultures and those that have various textures and aromas. Fermented dairy probiotic products are popular due to their differences in taste and their favourable physiological effects. However, recent upsurge in interest of consumers towards dairy alternatives has opened up new research areas for developing non-dairy probiotic products. Different substrates such as cereals, fruit juices, vegetables can be used utilized for delivering these beneficial microorganisms. This chapter provides an insight on the recent research/developments about selection criteria of bacteria as probiotics and in the field of technological properties of probiotics.