Impact of lactic acid bacteria and their metabolites on the techno-functional properties and health benefits of fermented dairy products.

After conversion of lactose to lactic acid, several biochemical changes occur such as enhanced protein digestibility, fatty acids release, and production of bioactive compounds etc. during the fermentation process that brings nutritional and quality improvement in the fermented dairy products (FDP). A diverse range of lactic acid bacteria (LAB) is being utilized for the development of FDP with specific desirable techno-functional attributes. This review contributes to the knowledge of basic pathways and changes during fermentation process and the current research on techniques used for identification and quantification of metabolites. The focus of this article is mainly on the metabolites responsible for maintaining the desired attributes and health benefits of FDP as well as their characterization from raw milk. LAB genera including Lactobacillus, Streptococcus, Leuconostoc, Pediococcus and Lactococcus are involved in the fermentation of milk and milk products. LAB species accrue these benefits and desirable properties of FDP producing the bioactive compounds and metabolites using homo-fermentative and heterofermentative pathways. Generation of metabolites vary with incubation and other processing conditions and are analyzed and quantified using highly advanced and sophisticated instrumentation including nuclear magnetic resonance, mass-spectrometry based techniques. Health benefits of FDP are mainly possible due to the biological roles of such metabolites that also cause technological improvements desired by dairy manufacturers and consumers.

Influence of lactic acid fermentation on the microbiological parameters, biogenic amines, and volatile compounds of bovine colostrum.

In this study we hypothesized that the relations between the bovine colostrum (BC) microbiota, biogenic amine (BA) as well as volatile compound (VC) profiles can lead to new deeper insights concerning the BC changes during the biological preservation. To implement such an aim, BC samples were collected from 5 farms located in Lithuania and fermented with Lactiplantibacillus plantarum and Lacticaseibacillus paracasei strains. Nonfermented and fermented BC were subjected to microbiological [lactic acid bacteria (LAB), Escherichia coli, and total bacteria (TBC), total Enterobacteriaceae (TEC) and total mold and yeast (M-Y) viable counts] and physicochemical (pH, color coordinates, BA content and VC profile) parameters evaluation, and the relationship between the tested parameters were also further analyzed. In comparison pH and dry matter (DM) of nonfermented samples, significant differences were not found, and pH of BC was, on average, 6.30, and DM, on average, 27.5%. The pH of fermented samples decreased, on average, until 4.40 in Lp. plantarum fermented group, and, on average, until 4.37 in Lc. paracasei fermented group. Comparing color characteristics among nonfermented BC groups, significant differences between lightness (L*) and yellowness (b*) were not detected, however, the origin (i.e., agricultural company), LAB strain used for fermentation and the interaction between these factors were statistically significant on BC redness (a*) coordinate. The microbial contamination among all the tested BC groups was similar. However, different LAB strains used for BC fermentation showed different effects toward the microbial contamination reduction, and specifically Lc. paracasei was more effective than Lp. plantarum strain. Predominant BA in BC were putrescine and cadaverine. The main VC in nonfermented and fermented BC were decane, 2-ethyl-1-hexanol, dodecane, 1,3-di-tert-butylbenzene, 3,6-dimethyldecane and tetradecane. Moreover, this study showed worrying trends with respect to the frozen colostrum storage, because most of the dominant VC in BC were contaminants from the packaging material. Additionally, significant correlations between separate VC and microbial contamination were obtained. Finally, these experimental results showed that the separate VC in BC can be an important marker for biological as well as chemical contamination of BC. Also, it should be pointed out that despite the fermentation with LAB is usually described as a safe and natural process with many advantages, control of BA in the end product is necessary.

Betaine as a Functional Ingredient: Metabolism, Health-Promoting Attributes, Food Sources, Applications and Analysis Methods.

Betaine is a non-essential amino acid with proven functional properties and underutilized potential. The most common dietary sources of betaine are beets, spinach, and whole grains. Whole grains-such as quinoa, wheat and oat brans, brown rice, barley, etc.-are generally considered rich sources of betaine. This valuable compound has gained popularity as an ingredient in novel and functional foods due to the demonstrated health benefits that it may provide. This review study will provide an overview of the various natural sources of betaine, including different types of food products, and explore the potential of betaine as an innovative functional ingredient. It will thoroughly discuss its metabolic pathways and physiology, disease-preventing and health-promoting properties, and further highlight the extraction procedures and detection methods in different matrices. In addition, gaps in the existing scientific literature will be emphasized.

Essential Components from Plant Source Oils: A Review on Extraction, Detection, Identification, and Quantification.

Oils derived from plant sources, mainly fixed oils from seeds and essential oil from other parts of the plant, are gaining interest as they are the rich source of beneficial compounds that possess potential applications in different industries due to their preventive and therapeutic actions. The essential oils are used in food, medicine, cosmetics, and agriculture industries as they possess antimicrobial, anticarcinogenic, anti-inflammatory and immunomodulatory properties. Plant based oils contain polyphenols, phytochemicals, and bioactive compounds which show high antioxidant activity. The extractions of these oils are a crucial step in terms of the yield and quality attributes of plant oils. This review paper outlines the different modern extraction techniques used for the extraction of different seed oils, including microwave-assisted extraction (MAE), pressurized liquid extraction (PLE), cold-pressed extraction (CPE), ultrasound-assisted extraction (UAE), supercritical-fluid extraction (SFE), enzyme-assisted extraction (EAE), and pulsed electric field-assisted extraction (PEF). For the identification and quantification of essential and bioactive compounds present in seed oils, different modern techniques-such as high-performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared spectroscopy (FTIR), gas chromatography-infrared spectroscopy (GC-IR), atomic fluorescence spectroscopy (AFS), and electron microscopy (EM)-are highlighted in this review along with the beneficial effects of these essential components in different in vivo and in vitro studies and in different applications. The primary goal of this research article is to pique the attention of researchers towards the different sources, potential uses and applications of oils in different industries.

Biodiversity and biotechnological properties of lactic acid bacteria isolated from traditional Moroccan sourdoughs.

The present study aimed at characterizing lactic acid bacteria (LAB) strains isolated from traditional sourdoughs collected in different regions of Morocco. Isolated strains were firstly identified using Gram staining and catalase reaction test. Presumptive LAB strains were then checked for various phenotypical properties including growth at 45 °C, resistance to NaCl, enzyme production, acidification capacity, diacetyl and exopolysaccharide (EPS) production, and antifungal activity. Finally, selected LAB strains were identified using 16S rDNA sequencing. Results showed that 32.1% of the isolates were thermophilic (45 °C) and 83.9% were resistant to NaCl (6.5%). Moreover, 51.7 and 37.5% were able to produce diacetyl and EPS, respectively. Regarding enzyme production, 55.3 and 7.1% of the isolates showed lipolytic and proteolytic activities, respectively. Low pH values (3.37-3.76) were obtained after 24 h of incubation of LAB strains in de Man, Rogosa and Sharpe (MRS) broth. Antifungal activity test against Aspergillus flavus, Aspergillus niger and Penicillium spp. showed an inhibition rate up to 50%. Bacterial DNA sequencing showed that LAB isolates belong to seven species, chiefly Levilactobacillus brevis, Lentilactobacillus parabuchneri, Lactiplantibacillus plantarum, Pediococcus pentosaceus, Enterococcus hirae, Bifidobacterium pseudocatenulatum, and Companilactobacillus paralimentarius. These findings, for the first time in Moroccan sourdoughs, indicate that the isolated LAB strains have good multifunctional properties and could be suitable as good starters for sourdough bread production under controlled conditions.

Determinants of economic motivations for food choice: insights for the understanding of consumer behaviour.

Food consumption involves several dimensions, being some of them directly associated with the consumers' characteristics. The interrelationships between these domains impact consumer behaviour for food choice and the consequent decisions for food consumption. In these frameworks, economic motivations are determinant. On the other hand, the scientific literature highlights that the economic-based stimuli to choose food is still underexplored. In this perspective, the objective of this study was to assess the main sociodemographic and anthropometric determinants of the economic motivations for food choice. For that, a questionnaire survey was carried out involving 11,919 respondents from 16 countries. A validated questionnaire was used, translated into the native languages in all participating countries, using a back-translation process. First, the information obtained was assessed through factor analysis to reduce the number of variables associated with the economic motivations and to identify indexes. After, and considering the indexes obtained as dependent variables, a classification and regression tree analysis was performed. As main insights, it is highlighted that the main determinants of the economic motivations are country of residence, age, gender, civil state, professional activity, educational level, living environment, responsibility for buying food, weight, height, body mass index, healthy diets and physical exercise practices. Additionally, the results also reveal that economic motivations may be associated with two indexes, one related to convenience attitudes and the other to quality concerns. Finally, the younger persons and the women are the social groups more concerned with healthy diets and food quality. In conclusion, this work confirmed that food choice is to a high extent influenced by several sociodemographic and behavioural factors.

Fermented, ultrasonicated, and dehydrated bovine colostrum: Changes in antimicrobial properties and immunoglobulin content.

This study evaluated the influence of fermentation with Lactobacillus plantarum LUHS135 and Lactobacillus paracasei LUHS244, ultrasonication, and different methods of dehydration on the content of IgG, IgA, and IgM in bovine colostrum (BC), as well as the antimicrobial activity of the treated and fresh BC samples [fresh = BC; freeze dried = BClyoph; vacuum dried (+45°C) = BCvacdried; BC fermented with LUHS135 = BCLUHS135; BC fermented with LUHS244 = BCLUHS244; BC fermented with LUHS135 and freeze dried = BCLUHS135lyoph; BC fermented with LUHS244 and freeze dried = BCLUHS244 lyoph; BC fermented with LUHS135 and vacuum dried = BCLUHS135 vacdried; BC fermented with LUHS244 and vacuum dried = BCLUHS244 vacdried; BC ultrasonicated and freeze dried = BCultr lyoph; BC ultrasonicated and vacuum dried = BCultr vacdried]. The antimicrobial activity was assessed against Klebsiella pneumoniae, Salmonella enterica, Pseudomonas aeruginosa, Acinetobacter baumanni, Proteus mirabilis, methicillin-resistant Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, Bacillus cereus, Streptococcus mutans, Enterobacter cloacae, Citrobacter freundii, Staphylococcus epidermis, Staphylococcus haemolyticus, and Pasteurella multocida using the agar well diffusion method, as well as in liquid medium. In liquid medium analysis showed that the fermented BC samples had the broadest antimicrobial spectrum (of 15 tested pathogenic strains, BCLUHS135 vacdried and BCLUHS135lyoph inhibited 13; BCLUHS244 vacdried inhibited 12; and BCLUHS135, BCLUHS244, and BCLUHS244 lyoph inhibited 11). Based on the inhibition zones, BCLUHS135lyoph samples exhibited the broadest inhibition spectrum, inhibiting the growth of 12 of the 15 tested pathogenic strains). According to the lactic acid bacteria strain selected for BC fermentation, different properties of the BC will be obtained. To ensure a broad antimicrobial spectrum and high IgG content, fermentation with LUHS135 can be recommended (IgG concentration in BCLUHS135 was retained), whereas fermentation with LUHS244 will provide a high IgM concentration (IgM concentration increased by 48.8 and 21.6% in BCLUHS244 and BCLUHS244lyoph samples, respectively). However, IgA is very sensitive for fermentation, and further studies are needed to increase IgA stability in BC. Finally, fermented BC can be recommended as a food/beverage ingredient, providing safety, as well as improved functionality through displaying a broad spectrum of antimicrobial activities.

Influence of sociodemographic factors on eating motivations - modelling through artificial neural networks (ANN).

This study aimed at investigating the influence of some sociodemographic factors on the eating motivations. A longitudinal study was carried conducted with 11960 participants from 16 countries. Data analysis included t-test for independent samples or ANOVA, and neural network models were also created, to relate the input and output variables. Results showed that factors like age, marital status, country, living environment, level of education or professional area significantly influenced all of the studied types of eating motivations. Neural networks modelling indicated variability in the food choices, but identifying some trends, for example the strongest positive factor determining health motivations was age, while for emotional motivations was living environment, and for economic and availability motivations was gender. On the other hand, country revealed a high positive influence for the social and cultural as well as for environmental and political and also for marketing and commercial motivations.

Influence of microbial and chemical contaminants on the yield and quality of ethanol from wheat grains.

BACKGROUND: Higher alcohols and esters have a negative impact on ethanol quality; therefore, to analyze the influence of mycotoxins and pesticides on higher alcohols and esters formation during ethanol production from contaminated cereal grains is of outstanding importance. RESULTS: In this study, the yield of ethanol and the composition of volatile by-products (acetaldehyde, methyl acetate, ethyl acetate, methanol, propanol, isobutanol, amyl and isoamyl alcohols) after fermentation of wheat grains artificially contaminated with Fusarium sporotrichioides and pesticides (triasulfuron and sulfosulfuron) were analyzed. Wheat grains contamination with triasulfuron significantly reduced ethanol yield and increased isobutanol and ethyl acetate content. Moreover, wheat grains infection with F. sporotrichioides significantly increased methyl acetate, ethyl acetate, isobutanol, and amyl and isoamyl alcohols content. Significant differences between pesticides and wheat variety on volatile compounds formation in ethanol has been estimated. CONCLUSION: The results showed that grains contaminated with F. sporotrichioides and pesticides significantly influenced the process of alcoholic fermentation that leads to variation of by-products in ethanol, including higher alcohols, esters, and aldehydes. © 2018 Society of Chemical Industry.

Improvement of the antimicrobial activity of lactic acid bacteria in combination with berries/fruits and dairy industry by-products.

BACKGROUND: By-products from berries/fruits (B/F) and the dairy industry (DI) are an important environmental issue in many countries. In the present study, the concept of an improvement of the antimicrobial activity of lactic acid bacteria (LAB) in combination with B/F (raspberries, blackcurrants, apples, rowanberries) and DI by-products was analysed. Antimicrobial activities of the B/F by-products and LAB (13 LAB strains were estimated against 15 pathogenic strains) were evaluated, with whey substrate being used for the selected and the highest antimicrobial activities showing LAB cultivation. RESULTS: The broadest spectrum of pathogenic bacteria inhibition was shown by lyophilised blackcurrant and apple by-products, which inhibited 13 and 12 pathogenic strains of the 15 strains analysed, respectively. The strongest inhibition of the tested pathogens were shown by the Lactobacillus uvarum LUHS245 and Lactobacillus casei LUHS210 and, for the abovementioned LAB biomass preparation, whey enriched with 2.5 g 100 g-1 glucose, 2.0 g 100 g-1 yeast extract and 0.5 g 100 g-1 saccharose is a suitable and sustainable substrate. The B/F by-product's antimicrobial activity can be enhanced in combination with the LUHS245 and LUHS210 strains. CONCLUSION: LAB, B/F and DI by-products can be used for preparation of antimicrobial products because the combination of compounds from different origins showed higher antimicrobial properties. © 2019 Society of Chemical Industry.

Application of antifungal lactobacilli in combination with coatings based on apple processing by-products as a bio-preservative in wheat bread production.

In this study various coatings from apple press cake (AP) with immobilized antifungal bacterial cells were used for bread surface treatment to increase anti-moulding effect. The antifungal effect and technological properties of newly isolated Lactobacillus coryniformis LUHS71, L. curvatus LUHS51, L. farraginis LUHS206 and Leuconostoc mesenteroides LUHS225 strains. Then, the lactobacilli were tested for the effects of incorporation of sourdough on acrylamide formation in bread and antifungal effect against moulds commonly associated with bread spoilage. The addition of 15-20% of sourdoughs significantly (p = 0.0001) improved bread volume and crumb porosity depending on LAB strain, and reduced acrylamide formation on average by 23% (for LUHS51 and LUHS206) by 54% (for LUHS71 and LUHS225) compared to control bread. Additionally, the use of AP-LAB coatings prolonged shelf life from 3 to 6 days for control bread, and up to 9 days for sourdough breads. The combination of antifungal LAB sourdough and the AP-LAB coating leads to produce high quality bread with extended shelf life and would be a new and promising environmentally-friendly technological alternative.

Agar-immobilized basil-lactic acid bacteria bioproducts as goat milk taste-masking agents and natural preservatives for the production of unripened goat cheese.

Goat milk cheeses have become popular recently; however, many consumers do not choose these products because they have specific sensory properties that are not acceptable to all consumers and the shelf life of the cheese is short. The concept of this work was to increase overall acceptability and shelf life of unripened goat milk cheese by using Ocimum basilicum and lactic acid bacteria (Lactobacillus plantarum LUHS135, Lactobacillus paracasei LUHS244, Pediococcus pentosaceus LUHS100, Pediococcus acidilactici LUHS29, and Lactobacillus brevis LUHS140) bioproducts (basil-LAB) immobilized in agar. A basil-LAB bioproduct could be a promising multifunctional ingredient for cheese manufacturing because it has a low pH, high LAB count, and high total phenolic compound content (after fermentation pH decreased by 25.4%, LAB count averaged 7.2 log10 cfu/g, and total phenolic compound content increased by 30.9%). Use of different LAB in the preparation of basil-LAB bioproducts had a significant influence on cheese pH and hardness, and compared with cheese samples prepared with nonfermented basil, cheese samples prepared with basil-LAB bioproducts had, on average, higher pH (by 2.6%) and lower hardness (by 36.0%), similar to the control cheese (without basil). Overall acceptability of cheese was significantly influenced by the basil-LAB bioproduct immobilization process; in all cases, cheese samples prepared with fermented and immobilized basil-LAB bioproduct had better acceptability (5 points). After 120 h of storage, cheese samples prepared with basil-LAB bioproducts fermented with LUHS135, LUHS244 and LUHS140, no enterobacteria were found, and we detected strong negative and moderate negative correlations, respectively, of LAB count with enterobacteria count and yeast/mold count (r = -0.7939 and r = -0.4495, respectively). Finally, immobilization increased LAB viability in fresh goat milk cheese, which led to a reduction in enterobacteria and mold/yeast contamination during storage and an increase in overall acceptability compared with nonimmobilized basil-LAB. Therefore, basil-LAB bioproducts fermented with LUHS135, LUHS244, and LUHS140 strains can be recommended for preparing fresh goat milk cheese with extended shelf life and high acceptability.

The effects of ultrasonication, fermentation with Lactobacillus sp., and dehydration on the chemical composition and microbial contamination of bovine colostrum.

The aim of this study was to evaluate the influence of ultrasonication, fermentation with Lactobacillus plantarum LUHS135 and Lactobacillus paracasei LUHS244, and different methods of dehydration on the chemical composition of bovine colostrum (BC), including the fatty acid and free amino acid profile and the content of micro- and macroelements. In addition, we analyzed the changes in lactic acid bacteria count, microbial contamination (aerobic mesophilic spore-forming bacteria, enterobacteria including Escherichia coli, and fungi/yeasts), the abundance of biogenic amines, and the concentration of nucleotide monophosphates. Significant effects of different treatments on the free amino acid profile were established, and an increase of lysine concentration by 1.2 to 95.9% was observed in treated BC. All of the treatments reduced the concentration of cadaverine, histamine, and tyramine in BC. The concentrations of macro- and microelements in BC followed the following order Ca > Na > K > Mg and Zn > Fe > Sr > Ba > Mn > Cu > Al > Se > Mo > Cr > Ni > Sn > Co > Pb > Cd. By combining the fermentation with Lactobacillus plantarum strain LUHS135 and vacuum drying, it was possible to increase the abundance of nucleotide monophosphates by more than 100%. All of the treatments reduced the microbial contamination of BC. Thus, the combination of ultrasonication, fermentation, and dehydration can be used for improving the properties and safety of BC.

Application of hydrolases and probiotic Pediococcus acidilactici BaltBio01 strain for cereal by-products conversion to bioproduct for food/feed.

The aim of this study was to apply the enzymatic treatment and fermentation by Pediococcus acidilactici BaltBio01 strain for industrial cereal by-products conversion to food/feed bioproducts with high amount of probiotic lactic acid bacteria (LAB). LAB propagated in potato media and spray-dried remained viable during 12 months (7.0 log10 cfu/g) of storage and was used as a starter for cereal by-products fermentation. The changes of microbial profile, biogenic amines (BAs), mycotoxins, lactic acid (L+/D-), lignans and alkylresorcinols (ARs) contents in fermented cereal by-product were analysed. Cereal by-products enzymatic hydrolysis before fermentation allows to obtain a higher count of LAB during fermentation. Fermentation with P. acidilactici reduce mycotoxins content in fermented cereal by-products. According to our results, P. acidilactici multiplied in potato juice could be used for cereal by-products fermentation, as a potential source to produce safer food/feed bioproduct with high amount of probiotic LAB for industrial production.

Non-Alcoholic Beverages from Fermented Cereals with Increased Oligosaccharide Content.

The aim of this study is to develop a new technology for making traditional Lithuanian non-alcoholic beverage kvass from fermented cereals by extending the spectrum of raw materials (extruded rye) and applying new biotechnological resources (xylanolytic enzymes and lactic acid bacteria (LAB)) to improve its functional properties. Arabinoxylans in extruded rye were very efficiently hydrolysed into oligosaccharides by xylanolytic complex Ceremix Plus MG. Using Ceremix Plus MG and LAB fermentation, the yield of arabinoxylooligosaccharides and xylooligosaccharides in beverage was increased to 300 and 1100 mg/L, respectively. Beverages fermented by LAB had lower pH values and ethanol volume fraction compared to the yeast-fermented beverage. The acceptability of the beverage fermented by Lactobacillus sakei was higher than of Pediococcus pentosaceus- or yeast- -fermented beverages and similar to the acceptability of commercial kvass made from malt extract. The results showed that extruded rye, xylanolytic enzymes and LAB can be used for production of novel and safe high-value non-alcoholic beverages.

Amino acids profile and antioxidant activity of different Lupinus angustifolius seeds after solid state and submerged fermentations.

The objective of this study was to investigate the amino acids profile, total phenolic compounds (TPC) content, antioxidant activity after submerged (SmF) and solid state (SSF) fermentations of different Lupinus angustifolius seeds by the Lactobacillus sakei KTU05-6. Additionally, the impact of different lupin seeds as fermentation media for LAB biomass and d/l-lactic acid production was analysed. The d/l ratio for SmF and SSF treated lupin samples varied from 0.15 to 0.45 and from 0.12 to 0.46, 16 respectively. Nutritional analysis highlighted a substantial increase in the TPC content and antioxidant activity up to 31.5-48.8% for SSF treated L. angustifolius samples compared to unfermented. The interaction between analysed factors (lupin variety and fermentation conditions) had a significant influence on essential and nonessential amino acids profile.

Phytase activity of lactic acid bacteria and their impact on the solubility of minerals from wholemeal wheat bread.

The objective of this study was to determinate phytase activity of bacteriocins producing lactic acid bacteria previously isolated from spontaneous rye sourdough. The results show that the highest extracellular phytase activity produces Pediococcus pentosaceus KTU05-8 and KTU05-9 strains with a volumetric phytase activity of 32 and 54 U/ml, respectively, under conditions similar to leavening of bread dough (pH 5.5 and 30 °C). In vitro studies in simulated gastrointestinal tract media pH provide that bioproducts prepared with P. pentosaceus strains used in wholemeal wheat bread preparation increase solubility of iron, zinc, manganese, calcium and phosphorus average 30%. Therefore, P. pentosaceus KTU05-9 and KTU05-8 strains could be recommended to use as a starter for sourdough preparation for increasing of mineral bioavailability from wholemeal wheat bread.

The Use of Tomato Powder Fermented with Pediococcus pentosaceus and Lactobacillus sakei for the Ready-to-Cook Minced Meat Quality Improvement.

In this study, the influence of lactic acid fermentation on the quality of tomato powder was evaluated. The effect of adding fermented tomato powder to ready-to-cook minced pork meat to improve its nutritional value and sensory characteristics was also analysed. The cell growth of Lactobacillus sakei (7.53 log CFU/g) was more intense in the medium containing tomato powder, compared to the growth of Pediococcus pentosaceus (6.35 log CFU/g) during 24 h of fermentation; however, higher acidity (pH=4.1) was observed in the tomato powder samples fermented with Pediococcus pentosaceus. The spontaneous fermentation of tomato powder reduced cell growth by 38% and pH values slightly increased to 4.17, compared to the fermentation with pure LAB. The lactofermentation of tomato powder increased the average ß-carotene and lycopene mass fractions by 43.9 and 50.2%, respectively, compared with the nonfermented samples. Lycopene and ß-carotene contents in the ready-to-cook minced pork meat were proportional to the added tomato powder (10 and 30%). After cooking, ß-carotene and lycopene contents decreased, on average, by 24.2 and 41.2%, respectively. The highest loss (up to 49.2%) of carotenoids was found in samples with 30% nonfermented tomato powder. Tomato powder fermented with 10% Lactobacillus sakei KTU05-6 can be recommended as both a colouring agent and a source of lycopene in the preparation of ready-to-cook minced pork meat.

Solid state fermentation with lactic acid bacteria to improve the nutritional quality of lupin and soya bean.

BACKGROUND: The ability of bacteriocin-like inhibitory substance (BLIS)-producing lactic acid bacteria (LAB) to degrade biogenic amines as well as to produce L(+) and D(-)-lactic acid during solid state fermentation (SSF) of lupin and soya bean was investigated. In addition, the protein digestibility and formation of organic acids during SSF of legume were investigated. RESULTS: Protein digestibility of fermented lupin and soya bean was found higher on average by 18.3% and 15.9%, respectively, compared to untreated samples. Tested LAB produced mainly L-lactic acid in soya bean and lupin (D/L ratio 0.38-0.42 and 0.35-0.54, respectively), while spontaneous fermentation gave almost equal amounts of both lactic acid isomers (D/L ratio 0.82-0.98 and 0.92, respectively). Tested LAB strains were able to degrade phenylethylamine, spermine and spermidine, whereas they were able to produce putrescine, histamine and tyramine. CONCLUSIONS: SSF improved lupin and soya bean protein digestibility. BLIS-producing LAB in lupin and soya bean medium produced a mixture of D- and L-lactic acid with a major excess of the latter isomer. Most toxic histamine and tyramine in fermented lupin and soya bean were found at levels lower those causing adverse health effects. Selection of biogenic amines non-producing bacteria is essential in the food industry to avoid the risk of amine formation.

Safety and quality parameters of ready-to-cook minced pork meat products supplemented with Helianthus tuberosus L. tubers fermented by BLIS producing lactic acid bacteria.

The aim of this study was to evaluate the influence of additives of Jerusalem artichoke (JA), fermented with P. acidilactici KTU05-7, P. pentosaceus KTU05-9, L. sakei KTU05-6, on the quality and safety parameters of ready - to cook - minced pork (RCMP). Fermented JA additives reduced pH of the meat products and decreased water holding capacity (WHC) from 2.01 till 2.93 %. Concentrations of biogenic amines in RCMP with additives of the lactic acid bacteria (LAB) - fermented JA were significantly lower comparing with control sample. The number of pathogenic bacteria in artificially contaminated meat samples was significantly reduced in case of LAB-fermented JA additives. The highest antimicrobial activity was obtained using P. acidilactici fermented JA additives. The amounts of microbial pathogens E. coli and Ent. faecalis, S. aureus and Streptococcus spp. were determined 3.41, 3.38, 3,96 and 4.74 log CFU/g correspondingly, whereas without LAB-fermented JA additives were 8.94, 7.75, 8.82 and 8.58 log CFU/g, correspondingly. A possibility to improve sensory properties (flavor) of RCMP using LAB fermented JA additives was investigated. The composition of volatile compounds of RCMP without additive and with LAB-fermented JA additives was analyzed using gas chromatography-mass spectrometry (GC-MS). The results of sensory evaluation of meat products supplemented with fermented JA additives revealed specific odor, which is pleasant and acceptable for consumers might be explainable that LAB-fermented JA additives have shown considerable differences mainly due to the accumulation of volatiles such as toluene, ethylbenzene, decane, undecane, 2 methyl undecane. N-morpholinomethyl-isopropyl-sulfide, 6-undecilamine and N,N-dimethyl-1-pentadecanamine were not determined in RCMP with LAB-fermented JA additives. The results obtained show, that P. acidilactici fermented JA 5 % additive is most suitable for the RCMP processing in order to prevent microbiological spoilage, increase volatile compounds and acceptability of the products.