Lactic Acid Bacterial Counts Research Articles

Evaluation of Antidiabetic, Antioxidant and Other Phytochemical Properties of Thai Fruits, Vegetables and Some Local Food Plants

Antidiabetic, antioxidant, anti-acetylcholinesterase and prebiotic activities, total phenolics and flavonoids of 33 crude ethanolic extracts of Thai local fruits, vegetables and some local food plants were determined. Mangosteen (Garcinia mangostana) fruit peel and Indian gooseberry (Phyllanthus emblica) fruit extracts had highest antioxidant activity. Bamboo grass (Tiliacora triandra) leaf extract had strongest α-amylase inhibitory activity (78.28 % inhibition), while mulberry (Morus alba) fruit extract had strongest α-glucosidase inhibitory activity (59.63 % inhibition). Star cactus (Aloe vera) leaf pulp extract had strongest anti-acetylcholinesteraseVactivity (31.55 % inhibition). Indian gooseberry fruit and mangosteen fruit peel extracts had highest content of total phenolics and flavonoids, respectively. The extract with highest indigestible polysaccharide content was the extract of mangosteen fruit peels (188.62 mg/g extract), while those with relatively high indigestible polysaccharides were the extracts of pineapple fruits (Ananas comosus), lotus seeds (Nelumbo nucifera), black rice grains (Oryza sativa) and pisang mas banana fruits (Musa sapientum). Based on these properties, 5 plant extracts were selected to study for their prebiotic effect on growth and fermentation of Lactobacillus acidophilus, Lactobacillus bulgaricus and Streptococcus thermophilus in yogurt at 42 °C. Addition of lotus seed extract resulted in highest proliferation of these bacteria with 2.24 logCFU/g increase of total lactic acid bacterial counts in yogurt after 24 h fermentation, while addition of black rice grain, pisang mas banana fruit and pineapple fruit extracts caused good growth of these bacteria with 2.12 - 2.19 logCFU/g increase of total counts.

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

ObjectiveThe aims of this study were to select one strain of Lactobacillus plantarum (L. plantarum) 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.MethodsThree strains of indigenous L. plantarum starter culture (KL101, KL102, and KL103) were selected based on 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.ResultsKL102 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 a generation time than in the 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 Moo som inoculated with KL102 were lower amount those with TISIR543 (p<0.05).ConclusionKL102 was a suitable starter culture to reduce the biogenic amine formation in Moo som.

Isolation and characterisation of angiotensin converting enzyme (ACE) inhibitory peptides in fermented milk of malabari goat

A study was conducted to isolate and characterise the angiotensin converting enzyme (ACE) inhibitory peptides from fermented milk of Malabari goat. Goat milk was fermented with seven different lactic acid bacterial cultures including Lactobacillus acidophilus (MTCC 10307), L. plantarum (NCDC 379), L. casei (NCDC 017), L. bulgaricus (NCDC 253), L. paracasei sub sp . paracasei (NCDC 022), L. rhamnosus (MTCC 8712) and L. helveticus (NCDC 192). These cultures were inoculated at 3 and 4% levels for the preparation of fermented milk. The pH, titratable acidity, lactic acid bacterial count, proteolytic activity and ACE inhibitory activity of the fermented milk ranged from 4.07 to 5.69, 0.36 to 1.24% lactic acid, 9.79 to 10.25 log cfu/ml, 0.32 to 0.69 and 67.56 to 97.55%, respectively. The highest ACE inhibitory activity was observed in milk fermented with L. plantarum (NCDC 379). Fermented milk with high ACE inhibitory activity were subjected to reverse phase high performance liquid chromatography to isolate the ACE inhibitory peptides. Characterisation of the peptides was done by Tris-tricine SDS-PAGE. The molecular weight of ACE inhibitory peptides was 1.4 kDa. It can be concluded that Malabari goat milk fermented with lactic acid bacteria is a rich source of ACE inhibitory peptides.

Antioxidant effects of kimchi supplemented with black raspberry during fermentation protect against liver cirrhosis-induced oxidative stress in rats.

BACKGROUND/OBJECTIVESOxidative stress is a major effector of various diseases; accordingly, antioxidants are frequently ingested in order to prevent or alleviate disease symptoms. Kimchi contains various natural antioxidants, and it is known that the functional activity varies depending on the ingredients and fermentation state. Black raspberries (BR) contain various bioactive compounds with antioxidant effects. This study investigated the antioxidant and liver-protection effects of kimchi supplemented with black raspberry juice powder (BJP).MATERIALS/METHODSBJP-added kimchi (BAK; at 0.5%, 1%, and 2% concentrations of BJP) and control (without BJP) were prepared and fermented at 4℃ for 4 weeks. Changes in the antioxidant effects of BAK during fermentation were investigated. In addition, the protective activity of BAK against oxidative stress was investigated in a liver cirrhosis-induced animal model in vivo.RESULTSBAK groups showed the acidity and pH of optimally ripened (OR) kimchi at 2 weeks of fermentation along with the highest lactic acid bacterial counts. Additionally, BAK groups displayed a higher content of phenolic compounds and elevated antioxidant activities relative to the control, with the highest antioxidant effect observed at 2 weeks of fermentation of OR 1% BAK. After feeding the OR 1% BAK to thioacetamide-induced liver cirrhosis rats, we observed decreased glutamate oxaloacetate transaminase and glutamate pyruvate transaminase activities and elevated superoxide dismutase activity.CONCLUSIONSThese findings showed that the antioxidant effects of OR BAK and feeding of OR 1% BAK resulted in liver-protective effects against oxidative stress.

Quality improvement of spreadable processed cheese made from ultrafiltered milk retentates using commercial starter cultures.

This study was undertaken to evaluate the feasibility of using commercial starter cultures for quality improvement of spreadable processed cheese manufactured from ultrafiltered milk retentates. Compared to control, six samples of ultrafiltered milk retentate were incubated at 25 ℃ with starter cultures CHN-22, FRC-60, and ABT-8. Three samples were incubated for 24 h and the others were incubated for 72 h. Physicochemical, microbiological, and organoleptic characteristics in all treatments during the 90-day cold storage (6 ± 2 ℃) period were determined. The results showed that protein content of all treatments was significantly lower than the control. Utilization of starter cultures in ultrafiltered processed cheese production increased titratable acidity, where titratable acidity of the treatments (PC22-3, PC60-3, and PC8-3) was significantly higher than the other treatments and the control. PC8-1, PC60-1, and PC22-1 treatments were the highest penetrometer readings and with low firmness. All treatments had higher water soluble nitrogen/total nitrogen%, total bacterial viable and lactic acid bacterial counts especially PC22-3, PC60-3, and PC8-3 compared to the control. The results revealed that PC60-1 and PC22-3 treatments gained the highest acceptability scores than PC60-3, PC22-1, and the control.

Silages of Rye Harvested at Different Stages: A Study on Microbial Inoculants Responses in Improving Rye Silage Fermentation Quality

The present study analyzes the role of Lactic Acid Bacteria Mixture (LBM) on improving rye silage quality. Rye of four different stages (Booting, Heading, Flowering, and Late flowering) was collected and silage was prepared. The nutrient profile analysis of experimental silage groups showed no significant changes between control and LBM inoculation. Interestingly, the pH of rye silage in LBM treatments showed significant reduction than control (p<0.05) in all stages of rye silage. However, lowest pH (3.69) resulted on booting stage among other stages of rye. Subsequently significant lactic acid production was noted in all stages of LBM inoculation than control. Conversely maximum lactic acid production of (5.33%DM) was noted at booting stage followed by (4.86%DM) in heading stage. Further the lactic acid bacterial (LAB) count in LBM inoculated group showed significant increase than control. Similarly, the silage of booting stage group registered maximum LAB population (63.7 ×106CFU/g) after that heading stage (32.3 ×106CFU/g). Further significant reduction in yeast growth and no fungal growth was noted in all LPM treatment groups. Hence, LBM inoculants could be a better additive for improving rye silage quality.

Physicochemical, Microbial, and Sensory Properties of Queso Blanco Cheese Supplemented with Powdered Microcapsules of Tomato Extracts

The present study examined the physical, chemical, microbial, and sensory characteristics of Queso Blanco cheese supplemented with powdered microcapsules containing tomato extracts (0.5-2.0%) during storage at 7°C for 60 d. The lactic acid bacterial count and lycopene concentrations in Queso Blanco cheese supplemented with powdered microcapsules were significantly higher than those of the control. In a texture analysis, the gumminess, chewiness, and hardness values for Queso Blanco cheese were significantly higher with increasing concentrations of the powdered microcapsules containing tomato extracts. Total short-chain fatty acids in Queso Blanco cheese supplemented with powdered microcapsules containing tomato extracts were not significantly altered compared to the control. Sensory evaluation scores for the yellowness, tomato taste, and firmness of Queso Blanco cheese were significantly higher after supplementation with powdered microcapsules containing tomato extracts.

Culture-dependent and culture-independent assessment of spoilage community growth on VP lamb meat from packaging to past end of shelf-life

Packaging and storage temperature are important factors that influence the shelf-life of vacuum packed (VP) meat. In this study the shelf-life of VP bone-in lamb hind shanks stored at 8 °C and −1.2 °C was determined in parallel to analyses of starting and eventual spoilage bacterial communities via Illumina MiSeq based 16S rRNA amplicon sequencing. The mean total viable counts (TVC) and lactic acid bacterial viable counts (LAB) were observed to increase to log 7.5 CFU/cm2 and 7 CFU/cm2 after 6 and 42 days at 8 °C and −1.2 °C and stayed stable until shelf-life termination after 13 and 124 days, respectively. The sequence data showed initial communities were patchily distributed and were mainly derived from skin microbiome taxa likely prevalent within the abattoir. A broad diversity of VP meat associated specific spoilage organisms (SSO) were comparatively abundant in this initial population. Overtime meat spoilage communities developed a distinctive and stable microbiome. At −1.2 °C SSO included mainly Carnobacterium, Yersinia and Clostridium spp. while at 8 °C SSO expanded to include Hafnia, Lactococcus, Providencia spp. Growth curves inferred from the sequence data after taking into account rRNA copy number suggested that SSO growth rates were consistent with overall growth rates determined from TVC and LAB data and are predictable.

Quality attributes of dahi prepared from milk fortified with omega-3 fatty acids, phytosterols and polydetxrose.

In the present study, dahi prepared using milk fortified with omega-3 fatty acids (flaxseed oil), phytosterols and soluble fibre (polydextrose) through an oil-in-water emulsion was evaluated for the physico-chemical and sensory quality. The levels of fortificants in fortified dahi were also estimated. Fortification process did not affect the degree of fermentation in terms of pH and acidity. Sensory scores of fortified and control dahi did not differ significantly. Fortified dahi had lower viscosity, firmness and consistency, and higher water holding capacity (WHC) compared to control; however, significant differences were not observed in firmness and consistency values. Storage study indicated that pH, acidity, %WHC, firmness and consistency values and lactic acid bacterial counts did not differ significantly throughout storage period in both the dahi samples and recorded good sensory acceptability during storage. Fortified dahi provides 282.53mg, 415.92mg and 1.019g of α-linolenic acid, total phytosterols and polydextrose, respectively per 100g of product. Moreover, no loss in the initial content of ALA, phytosterols and polydextrose had occurred after 8days of storage period. The present study suggests the feasibility of adding flaxseed oil, phytosterols and polydextrose as functional ingredients in the form of water soluble emulsion to milk, which could be converted to dahi with acceptable properties and enhanced nutritional and therapeutic potency.

Biogenic Amine Formation and Microbiological Quality of Anchovy (Engraulis encrasicolus) Treated with Lavender and Lemon Balm Ethanol Extracts.

Biogenic amine formation and bacterial growth of vacuum-packed European anchovy treated with 1% lemon balm (LB) or lavender (LD) ethanol extracts was investigated. The treated samples were stored at 2 ± 1 °C for 11 d and analyzed for biogenic amines, total viable count, fecal coliform count, and lactic acid bacterial count. The analyses were done on 0, 4, 7, 9, and 11 d of storage. Both LB and LD extracts proved effective in reducing most biogenic amines, with histamine reduced by 3-fold compared to control. The calculated biogenic amine index showed that LB extract was the most effective in inhibiting the biogenic amine formation. The reduction in total viable count was low and the bacterial contamination reached more than 7 log cfu/g at the end of the storage period for all the samples. Moreover, the reduction in fecal coliform and lactic acid bacterial count by LB and LD extracts was below 1 log cfu/g. Treatment of European anchovy with LB and LD extracts proved to be a very effective preservation technique to reduce the biogenic amine formation and lower the risk of histamine fish poisoning but is not effective in reduction of bacterial load. Consequently, LB and LD extracts could be used to reduce the biogenic amine formation which provides additional safety prior to spoilage for histamine sensitive fish species.

Pediocin PA-1 containing fermented cheese whey reduces total viable count of raw buffalo (Bubalis bubalus) milk

The present study was carried out to enhance shelf life of raw buffalo milk by the use of pediocin PA-1 containing fermented cheese whey (PCFCW) as bio-preservative. Ten distinct genera of milk microbes could be identified as Streptococcus, Enterococcus, Salmonella, Campylobacter, Lactobacillus, Enterobacter, E. coli, Shigella, Candida and Aspergillus. For the production of PCFCW, supplemented cheese whey medium was fermented with Pediococcus pentosaceous NCDC 273 for 24 h. Partially purified PCFCW was prepared using ammonium sulphate precipitation followed by membrane ultrafiltration with 10 kDa and 3 kDa membrane (Millipore) respectively. The fraction between 10 and 3 kDa was used as bio-preservative. This bio-preservative was found to contain pediocin PA-1 at the level of 2.04 × 105 AU/ml. In view of the wide antibacterial spectrum of pediocin, the PCFCW formulation was added at 1%, 5%, and 10% (v/v) concentrations to raw buffalo milk to reduce total microbial load. A significant decrease (p˂0.05) was observed in total viable count on TGYEA, Staphylococcus aureus count on BPA, and lactic acid bacterial count on MRSA. However, the reduction in coliform count on VRBA and yeast-mould count on PDA was non-significant (p˂0.05). Therefore, it can be concluded that partially purified PCFCW was effective in reducing total microbial load in raw buffalo milk.

Preparation of Probiotic Apple Juice by Lactic Acid Fermentation

Fermentation of apple juice was done for 72 hrs by lactic acid bacteria (Lactobacillus plantarum and Streptococcus thermophilus)and physico-chemical characteristics of fermented apple juices were recorded at 0. 24, 48 and 72 hrs intervals. On the basis of highest lactic acid bacterial counts, rate of fermentation (°B/24hr), acidity, sugar utilization percentage, retention of ascorbic acid and total phenols, antioxidant activity and antimicrobial activity against pathogenic bacteria such as E. coli and S. aureus, while lowest pH, coliform, yeast and mold counts, the best treatments L. plantarum 107cfu/ml for apple fermented apple juice was selected for storage study viz. During fermentation both vitamin C and total phenols declined, while, the antioxidant activity, antimicrobial activity, viable cell counts and lactic acid bacteria counts were increased. As the antimicrobial activity increased, the counts of coliform, yeast and mold declined. During storage of selected treatment of fermented apple juice for four weeks at 4°C retained physico-chemical parameters above the value of significance. Lactic acid bacteria remained viable in prescribed number (4.76–6.00 × 106 cfu/ml), acid and bile resistance, imparted antimicrobial activity and antioxidant activity to the apple juices during storage and thus, could be called as probiotics juices. Based on the sensory evaluation (visual colour and flavours) of fermented apple juice, it was concluded that lactic acid fermentation did not influence the desirable characteristics of apple juices. So the probiotic juices were acceptable. Identification of lactic acid bacteria by biochemical test concluded that the bacteria were L. plantarum in apple juices which were inoculated in juices for fermentation, after storage apple juice were suitable for lactic acid fermentation to produce a probiotic beverage. So, this juice can serve as healthy beverage for vegetarians and lactose allergic consumers.

해조류 첨가 오메기술의 품질 특성

본 연구에서는 지역 특색을 살린 전통주를 개발하여 사장되고 있는 제주 전통주 문화를 정립하고자 제주지역의 대표적 민속주인 오메기술의 제조과정에 다양한 생리활성물질이 함유된 톳, 모자반과 같은 해조류를 물 첨가량 대비 5, 10%로 첨가한 후, 해조류의 함량 차이에 따른 오메기술의 발효중 pH, 산도, 알코올 함량, 색도, 미생물 수, 유기산 함량 및 항산화력을 측정하였다. pH는 담금 직후 4.80~5.35에서 발효 2일째 급격하게 감소하였고 발효기간에 따라 점차 낮아져 발효 10일에는 모자반을 10% 첨가한 오메기술이 3.72로 유의적으로 가장 낮았다. 총산은 담금 직후에 비해 발효 2일째 0.158~0.190%로 급격하게 증가하였고 발효기간에 따라 점차적으로 증가하는 경향을 보였다. 알코올 함량은 발효 2일째에 급격하게 상승하였으며 발효 4일째부터 완만하게 증가하여 발효 10일 8.37~9.00%로 나타났다. 색도는 발효 10일 L값과 a값, b값 모두 톳을 10% 첨가한 오메기술에서 높게 나타났다. 총균수와 젖산균 수는 발효 초기 증가하다가 발효 후기는 감소하는 경향을 나타내었는데 발효 10일째에 톳을 10% 첨가한 오메기술에서 총균수는 1.45×10⁸ CFU/mL, 젖산균 수는 2.21×10⁸ CFU/mL로 나타났다. 유기산에서는 lactic acid와 succinic acid가 많이 검출되었으며 lactic acid는 발효 10일째의 모자반 10%를 첨가한 오메기술에서 7.474 ㎎/mL로 가장 높게 나타났고 succinic acid는 발효 10일 0.598~0.924 ㎎/mL로 유의적인 차이가 없었다. 항산화 활성을 확인하기 위해 DPPH 및 ABTS radical 소거 활성을 측정한 결과 DPPH radical 소거 활성에서는 발효가 진행됨에 따라 점차 증가하여 발효 10일째에는 모자반을 10% 첨가한 오메기술이 69.81%로 가장 높게 나타났고, ABTS radical 소거 활성에서는 발효가 진행됨에 따라 증가하여 발효 8일째에 78.25~81.61%로 모자반을 10% 첨가한 오메기술에서 유의적으로 가장 높게 나타났으나 발효 10일째에는 모든 실험군에서 감소하였다. 본 실험결과에서는 전반적인 품질 비교를 통해 모자반을 10% 첨가한 오메기술이 다른 비교구에 비해 탁월한 결과를 보여 기능성 오메기술로서의 가능성을 확인할 수 있었으며, 이후 지역 특성을 살린 전통주로 기능성 오메기술을 상품화하기 위한 기초자료로서 유용하게 활용될 것으로 판단된다. 현재 오메기술의 소비자 기호도 조사를 수행하고 있으며 그 결과 또한 보고할 계획이다.

Heterofermentative lactic acid bacteria dominate in Korean commercial kimchi.

Lactic acid bacterial communities in kimchi prepared by representative Korean kimchi companies were investigated using a pyrosequencing method. The pH values of 9 kimchi varieties (K1-K9) ranged from 4.3 to 4.7, and total lactic acid bacterial (LAB) counts ranged from 1.3x107 to 1.6x109 CFU/g. Weissella, Lactobacillus, and Leuconostoc were the dominant genera accounting for 52, 28, and 20%, respectively, of identified genera. At the species level, Weissella koreensis (35%) dominated, followed by Lactobacillus graminis (13%), and Weissella cibaria (11%). Dominant LAB were all heterofermentative LAB. K1 had the most diverse operational taxonomic units (OTUs), and clustering analysis showed that distributions of microorganisms in K2, K6, K5, and K4 were similar each other. LAB communities in kimchi are diverse and heterofermentative LAB dominate in Korean commercial kimchi.

Substitution Effect of Enzymatically Hydrolyzed Purple Sweet Potato Powder on Skim Milk in Yogurt Preparation

Yogurt was prepared with different substitution ratio (10, 30, and 50% (w/w)) of skim milk with enzymatically hydrolyzed purple sweet potato powder (EHPSPP) and fermented at 40 o C for 15 h. Fermentation characteristics and antioxidant activities of the yogurt were evaluated in terms of acid production (pH and titratable acidity) and lactic acid bacterial counts and DPPH radical scavenging activity, respectively. After 15 h fermentation, titratable acidity of EHPSPP yogurt was 0.80�0.89% and was lower than that (0.93%) of yogurt made without EHPSPP. The acid production and the number of viable lactic acid bacterial cell decreased with increasing the substitution ratio. The sensory score of EHPSPP yogurt prepared with 30% substitution ratio showed the highest values in taste and overall acceptability among the tested yogurt preparations. DPPH radical scavenging activity increased with increasing the substitution ratio in yogurt fermented for 12 h. The total phenolic content of 30% EHPSPP yogurt was 40% higher than that of skim milk yogurt. These results suggest that EHPSPP can be used as substituent of skim milk and the optimum substitution ratio is around 30%.

Effect of a polypropylene ((PP) patch containing isothiocyanates (ITCs) extracted from horseradish (Armoracia rusticana) root on the shelf-life of low-salt Myeong-ran Jeotgal

The effect of isothiocyanates (ITCs) extracted from horseradish root in the vapor phase on shelf-life extension of low-salt Myeong-ran Jeotgal was evaluated. Microbiological analysis showed that total viable cell counts, lactic acid bacterial counts, and proteolytic bacterial counts were inhibited in 0.50 and 0.75mL of ITCs (200 mg/mL)-treated Myeong-ran Jeotgal at 5 and 10°C. Chemical analysis revealed that 0.50 and 0.75 mL of ITCs (200mg/mL) treatments retarded formation of volatile basic nitrogen and thiobarbituric acid-reactive substances and reduced accumulation of alkaline compounds in 0.50 and 0.75 mL of ITCs (200mg/mL)-treated Myeong-ran Jeotgal. Arrhenius equations and sensory evaluations confirmed that the freshness of 0.75mL of ITCs (200mg/mL)-treated Myeong-ran Jeotgal was better preserved than for controls and showed that 0.75 mL of ITCs (200 mg/mL)-treated Myeong-ran Jeotgal had a shelf life that was approximately 4 days at 5°C and 2 days at 10°C longer than controls.

굴(Crassostrea gigas) 패각 분말 첨가에 의한 배추김치의 식품학적 품질 변화

This study investigated the effects of adding oyster shell powder (OSP) from Crassostrea gigas on the food quality of Chinese cabbage Kimchi (CCK). We monitored the changes in microbial levels, pH, acidity and sensory evaluation during the fermentation of CCK treated with various contents of OSP. The microbial assay showed that adding OSP to CCK inhibited the growth of viable cells, total coliforms, and lactic acid bacteria, with the greatest growth inhibition against lactic acid bacteria over the fermentation period. After fermentation for 18 days, the lactic acid bacterial counts in CCK treated with OSP (0.3%, 0.5% and 1%) were at least 1 log CFU/g lower than those of control CCK. In addition, the pH and acidity of CCK treated with OSP were lower than in control CCK over the fermentation period. The overall sensory evaluation of CCK with 0.3% OSP was better than that of control CCK after fermentation for 24 days. In conclusion, OSP treatment, especially 0.3% OSP, enhances the food quality and extends the self-life of CCK, while minimizing the detrimental effects on its sensory characteristics.

Effect of Different Packaging Methods on the Quality of Stuffed and Sliced Mozzarella Cheese during Storage

Mozzarella produced with high moisture curd method was filled into a fibrous casing and was stored at 4C and 85% relative humidity for 5 days. Sliced cheese was packed in aerobic packaging (AP), vacuum packaging (VP) and modified atmosphere packaging (MAP) and was stored at 4C for 21 days. L* (lightness) value of the AP sample decreased, while an increased in other two treatments was detected. The a* (redness) values of VP and MAP samples decreased, while the values of AP samples increased. Mesophilic aerobic bacteria, yeast and mold counts increased in the AP samples, while that of the VP and MAP samples counts decreased. Lactic acid bacterial count decreased in all three samples and the greatest decrease with a value of 3.90 log cfu/g was detected in samples packed in aerobic conditions. Samples with MAP had significantly better sensory score (P < 0.05) than any other samples. Practical Applications Mozzarella cheese is a popular processed dairy product. Mozzarella cheese is primarily produced with water buffalo milk and cow milk. Mozzarella is produced using two different methods, which are based on dry matter ratio and shelf life. Mozzarella with low moisture is used in the pizza industry and has a longer shelf life. The other mozzarella has higher humidity content and a limited shelf life. Modified atmosphere packaging (MAP) is becoming more common and is successfully applied to different processed dairy products for extending the shelf life. To sum up, our study proves the efficacy of using different packaging methods (AP, VP or MAP) on the microbiological, chemical and sensory properties of sliced mozzarella.

Fermented and extruded wheat bran in piglet diets: impact on performance, intestinal morphology, microbial metabolites in chyme and blood lipid radicals

The aim of the present study was to evaluate the influence of native, fermented and extruded wheat bran on the performance and intestinal morphology of piglets. Additionally, short-chain fatty acids (SCFA), biogenic amines, ammonia, lactic acid, pH as well as E. coli and lactic acid bacterial counts were analysed in digesta samples from three gut sections. Furthermore, the antioxidant potential in blood samples was evaluated based on the lipid radicals formed. For this purpose, 48 newly weaned piglets (28 d old) were allocated to one of the four different dietary treatment groups: no wheat bran (Control), native wheat bran, fermented wheat bran as well as extruded wheat bran. Wheat bran variants were included at 150 g/kg into the diets. All diets were mixed to reach the calculated isonitrogenic nutrient contents. Gut tissue and digesta samples were collected from the proximal jejunum, the terminal ileum and the colon ascendens, blood samples directly at slaughter. Although none of the dietary interventions had an impact on performance parameters, the amount of goblet cells in the ileum was increased upon feeding native and extruded wheat bran, compared to fermented bran (p < 0.05). The E. coli counts in colonic chyme were significantly lower (p < 0.05) in the Control group compared to the groups fed with wheat bran. The concentration of SCFA showed differences for minor compounds (p < 0.05), while linear contrast analyses revealed a reduced concentration of total SCFA in the colon following the feeding of modified wheat bran compared to native wheat bran. This may suggest that several compounds are more easily digested already in the ileum, resulting in a reduced nutrient flow into the large intestine and therefore less unexploited digesta is available as substrate for the microorganisms there. Fermentation also resulted in a significant decrease of methylamine in the colon (p < 0.05), while other biogenic amines in the ileum and colon showed no statistically significant differences. The formation of lipid radicals was decreased (p < 0.05) after feeding native wheat bran compared to the Control group. These results suggest that fermentation and extrusion of wheat bran exert some different impact regarding their physiological mode of action.

Is there a potential consumer market for low-sodium fermented sausages?

The NaCl levels in dry fermented sausages were reduced by 50% or were substituted with KCl, CaCl2 , or a blend of KCl and CaCl2 (1:1). The quality, safety, and the potential consumer market of dry fermented sausages were assessed. Neither 50% reduction of the NaCl content nor the substitution of 50% of the NaCl with KCl influenced the fermentation and maturation process. However, when CaCl2 was used as the substitute salt (50%), there was a significant decrease in pH, an increase in the water activity, and a decrease in lactic acid and micrococcus bacterial counts. Overall, the sensory acceptance decreased in dry fermented sausages with reduced sodium content. However, cluster analysis and internal preference mapping revealed potential for commercialization of samples with 50% of the NaCl content substituted with KCl or with a mixture of KCl and CaCl2 (1:1).