Raw Salad Research Articles

Bacteriological Quality and Risk Factors for Contamination of Raw Mixed Vegetable Salads Served in Collective Catering in Abidjan (Ivory Coast)

The aim of this study was to determine the bacteriological quality of raw mixed vegetable salads served in collective catering in Abidjan and to assess the factors likely to favor contamination. An investigation was conducted to determine the practical risk of contamination. A total of 306 samples were collected and analyzed for the detection and enumeration of Enterobacteriaceae, E. coli and Salmonella according to standard microbiology methods. The most important risk factors were lack of training (96.7%), decontamination (84.0%), cross-contamination of vegetables in contact with fresh chicken or fish (76.7%) and salads that were uncovered and unprotected, thus exposed to the air and at ambient temperature for sale (97.7%). Theprevalence was 100%, 77.8% and 2.6% respectively for Enterobacteriaceae, E. coli and Salmonella. The average load of Enterobacteriaceae and E. coli was 4.93 log10 (CFU/g) and 1.89 log10 (CFU/g), respectively. Unsatisfactory microbiological quality samples were 52.3%. The results showed a failure of the sanitary quality in more than half of the products. Raising awareness in all of the workers in the food chain for vegetable salads is thus necessary to protect the health of the consumers.

Microbial Quality, Safety, and Pathogen Detection by Using Quantitative PCR of Raw Salad Vegetables Sold in Dhanbad City, India

Consumption of ready-to-eat fresh vegetables has increased worldwide, with a consequent increase in outbreaks caused by foodborne pathogens. In the Indian subcontinent, raw fresh vegetables are usually consumed without washing or other decontamination procedures, thereby leading to new food safety threats. In this study, the microbiological quality and pathogenic profile of raw salad vegetables was evaluated through standard protocols. In total, 480 samples (60 each of eight different salad vegetables) of cucumber, tomato, carrot, coriander, cabbage, beetroot, radish, and spinach were collected from different locations in Dhanbad, a city famous for its coal fields and often called the "Coal Capital of India." The samples were analyzed for total plate count, total coliforms, Escherichia coli , E. coli O157:H7, Listeria monocytogenes , and Salmonella spp. Incidences of pathogens were detected through quantitative PCR subsequent to isolation. Results showed that 46.7% (for total plate counts) and 30% (for total coliforms) of samples were unacceptable for consumption per the Food Safety and Standards Authority of India. Pathogenic microorganisms were detected in 3.7% of total samples. E. coli O157:H7 was detected in three samples of spinach (2) and beetroot ( 1 ); L. monocytogenes was detected in 14 samples of spinach ( 8 ), tomato ( 3 ), cucumber ( 2 ), and radish ( 1 ); and Salmonella spp. were detected in 16 samples of spinach ( 7 ), tomato ( 3 ), beetroot ( 2 ), cucumber ( 2 ), carrot ( 1 ), and radish ( 1 ). Pathogens were not detected in any of the cabbage and coriander samples.

Using farmer-prioritized vertisol management options for enhanced green gram and tomato production in central Kenya

Green gram ( Phaseolus aures L. ) and tomato ( Solanum lycopersicum L ) are widely grown in the vertisols of the Mwea Irrigation Scheme in Kenya alongside the rice fields. Green gram can fix nitrogen and is grown for its highly nutritious and curative seeds while tomato is grown for its fruit rich in fiber, minerals and vitamins. The two can be prepared individually or together in a variety of ways including raw salads and/or cooked/fried. They together form significant delicacies consumed with rice, which is the major cash crop grown in the black cotton soils. The crops can grow well in warm conditions but tomato is fairly adaptable except under excessive humidity and temperatures that reduce yields. Socio-economic prioritization by the farming community and on-farm demonstrations of soil management options were instituted to demonstrate enhanced green gram and tomato production in vertisol soils of lower parts of Kirinyaga County (Mwea East and Mwea West districts). Drainage management was recognized by the farming community as the best option although a reduced number of farmers used drainage and furrows/ridges, manure, fertilizer and shifting options in that descending order. Non-availability of labour and/or financial cost for instituting these management options were indicated as major hindrances to adoption of the yield enhancing options. Labour force was contributed to mainly by the family alongside hiring (64.2%) although 28% and 5.2%, respectively used hired or family labour alone. The female role in farming activities dominated while the male role was minimal especially at weeding. The youth role was insignificant and altogether absent at marketing. Despite the need for labour at earlier activities (especially when soil management options needed to be instituted) it was at the marketing stage that this force was directed. Soils were considered infertile by 60% but 40% indicated that their farms had adequate fertility. Analysis showed that with ridging, farm yard manure and fertilizer improved soil fertility, crop growth and income considerably. Phosphate and zinc enhancement reduced alkalinity and sodicity. Green gram and tomato yields increased under ridges and farm yard manure application by between 17-25% which significantly enhanced household incomes. Key words: Green gram, Tomato, Vertisol management, Household income, Mwea, Kenya

Prevalence of Parasitic contamination of salad vegetables in Ilorin, North Central, Nigeria

Fresh salad vegetables are essential for good health and they form a major component of human diet in every family in Nigeria. Raw vegetables can be agent of transmission of intestinal parasites. The aim of this study is to determine the parasitic contamination of salad vegetables sold at wholesale and retail markets around Ilorin metropolis. A total of 150 samples of salad vegetables obtained from five different markets were examined for both protozoa and helminth parasites using standard methods. About 25 samples each of lettuce, cabbage, carrot, cucumber, tomato and onion were examined. Eggs of Ascaris lumbricoides, Entamoeba histolytica/dispar , Enterobius vermicularis, cysts of Giardia lamblia, Fasciola hepatica, Trichuris trichiura, Strongyloides stercoralis, Balantidium coli and Necator americanus were detected in 28.0%, 23.3%, 11.7%, 5.0%, 6.7%, 3.3%, 10.0%, 3.3% and 8.3% respectively. Of the sampled areas, Ipata market recorded the highest parasite prevalence of 63.3% while G.R.A market recorded the lowest parasite prevalence of 13.3%. The most encountered parasite was A.lumbricoides (28.0%) while N.americanus was the least (3.3%) parasite found. The study revealed a high rate of protozoa and helminthes contamination of salad vegetables in the study areas. Parasitological contamination of raw salad vegetables sold in wholesale and retail markets in the study area may pose a health risk to consumers of such products. Keywords: Parasitic, Salad vegetables, Contamination, Ilorin, Nigeria.

Egg Consumption Increases Vitamin E Absorption from Co-Consumed Raw Mixed Vegetables in Healthy Young Men

Background: Most people living in the United States underconsume vitamin E, and dietary approaches to increase the absorption of vitamin E may help individuals to meet their body’s needs.Objective: We assessed the effect of adding cooked whole egg to a raw mixed-vegetable salad on α-tocopherol and γ-tocopherol absorption.Methods: With the use of a randomized-crossover design, 16 healthy young men [mean ± SD age: 24 ± 4 y; mean ± SD body mass index (in kg/m2): 24 ± 2] consumed the same salad (all served with 3 g canola oil) with no egg [control (CON)], with 75 g cooked egg [low egg (LE)], or with 150 g cooked egg [high egg (HE)]; a 1-wk dietary washout period was included between trials. For the first 7 d of each trial, participants consumed a low–vitamin E diet to reduce plasma vitamin E concentrations. Blood was collected hourly for 10 h and the triacylglycerol-rich lipoprotein fractions (TRLs) were isolated. α-Tocopherol and γ-tocopherol concentrations in TRLs were analyzed and composite areas under the curve (AUCs) were calculated.Results: The α-tocopherol 0- to 10-h AUCs (AUCs0–10 h) in TRLs was higher (P < 0.05) for the HE trial (least-squares mean ± SE: 981 ± 162 nmol/L ⋅ 10 h) than for the LE (311 ± 162 nmol/L ⋅ 10 h) and CON (117 ± 162 nmol/L ⋅10 h) trials, which did not differ from one another. The γ-tocopherol AUCs0–10 h in TRLs was also higher (P < 0.05) for the HE trial (402 ± 54 nmol/L ⋅ 10 h) than for the CON trial (72 ± 54 nmol/L ⋅ 10 h).Conclusion: The consumption of cooked whole eggs is an effective way to increase the absorption of α-tocopherol and γ-tocopherol from a co-consumed meal that naturally contains vitamin E, such as a raw mixed-vegetable salad, in healthy young men. This trial was registered at http://clinicaltrials.gov as NCT01951313.

Ethnobotany, Traditional Knowledge, and Diversity of Wild Edible Plants and Fungi: A Case Study in the Bandipora District of Kashmir Himalaya, India

ABSTRACTThis study explored the diversity of traditional knowledge, collected data on utilization, and identified and analyzed the wild edible plants and fungi of Kashmir Himalaya (India). Information was collected by interviews with 113 individuals during 2012–2014 from nine rural and mountainous areas. Data were classified as cooked vegetables, salads, spices, chutneys, herbal teas, home-made alcoholic drinks, soups, raw fruits, and underground snacks. Information was analyzed using use reports (UR), use values (UV), informant consensus (Fic), fidelity level (FL), and cultural importance index (CI) metrics. In total, 111 phytotaxa, distributed into 87 genera and 43 families, were identified as local edible resources. Overall, 94.25% of angiosperms, 3.45% gymnosperms, and 2.30% of cryptogams were documented as being used traditionally. Several taxa were highly cited (Amaranthus caudatus, Angelica archangelica, Asparagus racemosus, Berberis lycium, Fragaria vesca, Hippophae rhamnoides, Oxyria digyna, Juglans regia). Frequently used parts were young leaves (19.82%), fruits (15.32%), young twigs (9.01%), roots (8.11%), and tubers (6.31%). The most usage was mentioned for leafy vegetables (27.93%), followed by raw fruits (22.52%), herbal teas (14.41%), salads (9.91%), alcoholic drinks (6.31%), and snacks (4.50%). The high fidelity scores and informant consensus factors suggest that ethnobotanical knowledge could potentially guide the search for developing new nutraceutical products in the future.

Fruits and vegetables in the Brazilian Household Budget Survey (2008–2009): carotenoid content and assessment of individual carotenoid intake

The β-carotene, α-carotene, β-cryptoxanthin, lycopene, lutein, zeaxanthin, neoxanthin, violaxanthin concentrations in raw fruits and vegetables were compiled (19 fruits, 24 vegetables, and mixed fruit and salad dishes), using data from foods collected and analyzed in Brazil, by means of high-performance liquid chromatography with diode array detection. The food intake was obtained from the Food Consumption Module of the Household Budget Survey (2008–2009), recorded in 13569 households, representative of all Brazilian regions. Vegetables contributed more to vitamin A intake than fruits (70.3% vs 21.5% retinol equivalents), raw salads, pumpkin, kale and carrot being the main contributors. The mean dietary intakes of fruits (86g/d) and vegetables (64g/d) did not meet the recommendation of the WHO/FAO. All food items supplied β-carotene (0.9mg/p/d), the major contributors being kale, pumpkin and mango. β-Cryptoxanthin (0.1mg/p/d) was mostly supplied by orange, tangerine and papaya (87.4% of its intake). Lycopene (0.7mg/p/d) was found only in guava, watermelon and tomato. Lutein (0.8mg/p/d), violaxanthin and neoxanthin (0.6 and 0.2mg/p/d, respectively), were mainly supplied by green leafy vegetables and α-carotene (0.16mg/p/d) and zeaxanthin (0.06mg/p/d) by a small number of foods.

Prevalence of Pathogenic Bacteria Isolated from Two Selected Salad Vegetables and Antibiogram Profile of &lt;i&gt;Klebsiella&lt;/i&gt; spp.

The study was conducted to examine microbiological quality of raw salad vegetables of Jessore city of Bangladesh. Fourteen samples of two types of vegetables which are commonly used for salad eg. Tomato (&lt;i&gt;Lycopersicum esculentum&lt;/i&gt;) and Cucumber (&lt;i&gt;Cucumis sativus&lt;/i&gt;) were collected from different local markets of Jessore City and their bacteriological attributes were investigated using routine methods. All the vegetables were highly contaminated with coliforms and fecal coliforms. Range of Total Viable Count were 11x106 CFU/g to 20x107 CFU/g for tomato and 12x105 CFU/g to 24x107 CFU/g for cucumber, Total Coliform Count were 11x104 CFU/g to 2 x106 CFU/g for tomato and 10.2x103 CFU/g to 60x104 CFU/g for cucumber and Total Staphyllococcal Count were 11x104 CFU/g to 25x106 CFU/g for tomato and 10x104 CFU/g to 50x106 CFU/g for cucumber. Total coliforms were identified as &lt;i&gt;Escherichia coli&lt;i&gt;, &lt;i&gt;Klebsiella&lt;i&gt; spp., &lt;i&gt;Enterobacter&lt;i&gt; spp., &lt;i&gt;Citrobacter&lt;i&gt; spp. and &lt;i&gt;Shigella&lt;i&gt; spp. Antibiogram was conducted with twelve different antibiotics for some randomly selected pure colonies of &lt;i&gt;Klebsiella&lt;i&gt; spp. Multidrug resistance was observed in 90% isolates with resistance from two to six antibiotics. Hygienic practices should be followed in handling the vegetables in local markets and vegetables might have an important role as a source of antibiotic resistant bacteria.The Agriculturists 2015; 13(1) 9-17

Understanding the routes of contamination of ready-to-eat vegetables in the Middle East

In the developing countries, inaccessibility to safe water, lack of agricultural infrastructures and limitations to implementing good agricultural practices (GAP) are persistent challenges. To understand the spread of hazards and identify critical areas of transmission in the food chain, a total of 90 samples of raw salad vegetables (parsley, lettuce, radish) were collected from farms and post-harvest washing facilities (n = 12) in an extensively cultivated area in Lebanon, the Bekaa Valley and from wholesale market stalls traced back to surveyed fields. Our results showed high geometric mean indicator levels ranging from <0.7 to 7 log CFU/g (Escherichia coli), 1.69–8.16 log CFU/g (total coliforms), <0.7–8.39 log CFU/g (Staphylococcus aureus). The mean counts of total coliforms and E. coli on fresh produce followed an increasing trend from fields to the markets indicating potential sources of faecal contamination throughout the food chain. Of more concern was the presence of pathogens Listeria monocytogenes (14%) and S. aureus (45.5%) in fresh produce from harvest to retail, and Salmonella spp. was detected in 6.7% of the raw vegetables from the post-harvest washing areas. These results along with our observations highlight shortfalls in hygienic farming and postharvest practices, including the use of inappropriately treated manure and chicken litter to fertilize the crops on the fields which contributed to the high levels of S. aureus in the product at retail. Unregulated use of wash water, inadequate transportation and storage conditions with risks of cross contamination was also identified. Suggested control measures should mitigate the risks at the source and put emphasis on developing strict policies on monitoring the safety of water sources and on the application of the good agricultural and hygienic practices (GAP, GHP) on primary production stages, washing, transportation and storage at retail.

Effects of egg consumption on carotenoid absorption from co-consumed, raw vegetables

Dietary lipids are one of the most effective stimulators of carotenoid absorption, but very limited data exist on the impact of endogenous food sources of lipids to enhance carotenoid absorption. The co-consumption of whole egg with carotenoid-rich foods may increase overall carotenoid absorption via lipid-rich egg yolk. We designed this study to assess the effects of egg consumption on carotenoid absorption from a carotenoid-rich, raw mixed-vegetable salad. Healthy young men (n = 16) consumed the same salad (all served with 3 g canola oil) with no egg (control), 75 g scrambled whole eggs (1.5 eggs) [low egg (LE)], and 150 g scrambled whole eggs (3 eggs) [high egg (HE)] (a randomized crossover design). Control, LE, and HE meals contained 23 mg, 23.4 mg (0.4 mg from eggs), and 23.8 mg (0.8 mg from eggs) total carotenoids and 3 g, 10.5 g (7.5 g from eggs), and 18 g (15 g from eggs) total lipids, respectively. Blood was collected hourly for 10 h, and the triacylglycerol-rich lipoprotein (TRL) fraction was isolated. Total and individual carotenoid contents, including lutein, zeaxanthin , α-carotene, β-carotene, and lycopene in TRL were analyzed, and composite areas under the curve (AUCs) were calculated. The total mean (±SE) carotenoid AUC0-10h in TRL was higher for the HE meal than for LE and control meals [125.7 ± 19.4(a) compared with 44.8 ± 9.2(b) compared with 14.9 ± 5.2(b) nmol/L · 10 h, respectively (values without a common superscript letter differ); P < 0.0001]. The TRL AUC(0-10h) of lutein and zeaxanthin increased 4-5-fold (P < 0.001), and the TRL AUC(0-10h) of carotenoid not present in eggs, including α-carotene, β-carotene, and lycopene, increased 3-8-fold (P < 0.01) for the HE meal compared with the control meal. These findings support the claim that co-consuming cooked whole eggs is an effective way to enhance carotenoid absorption from other carotenoid-rich foods such as a raw mixed-vegetable salad. This trial was registered at clinicaltrials.gov as NCT01951313.

Discovery of the glycogen phosphorylase-modulating activity of a resveratrol glucoside by using a virtual screening protocol optimized for solvation effects.

The identification of natural products that can modulate blood glucose levels is of great interest as it can possibly facilitate the utilization of mild interventions such as herbal medicine or functional foods in the treatment of chronic diseases like diabetes. One of the established drug targets for antihyperglycemic therapy is glycogen phosphorylase. To evaluate the glycogen phosphorylase inhibitory properties of an in-house compound collection consisting to a large extent of natural products, a stepwise virtual and experimental screening protocol was devised and implemented. The fact that the active site of glycogen phosphorylase is highly hydrated emphasized that a methodological aspect needed to be efficiently addressed prior to an in silico evaluation of the compound collection. The effect of water molecules on docking calculations was regarded as a key parameter in terms of virtual screening protocol optimization. Statistical analysis of 125 structures of glycogen phosphorylase and solvent mapping focusing on the active site hydration motif in combination with a retrospective screening revealed the importance of a set of 29 crystallographic water molecules for achieving high enrichment as to the discrimination between active compounds and inactive decoys. The scaling of Van der Waals radii of system atoms had an additional effect on screening performance. Having optimized the in silico protocol, a prospective evaluation of the in-house compound collection derived a set of 18 top-ranked natural products that were subsequently evaluated in vitro for their activity as glycogen phosphorylase inhibitors. Two phenolic glucosides with glycogen phosphorylase-modulating activity were identified, whereas the most potent compound affording mid-micromolar inhibition was a glucosidic derivative of resveratrol, a stilbene well-known for its wide range of biological activities. Results show the possible phytotherapeutic and nutraceutical potential of products common in the Mediterranean countries, such as red wine and Vitis products in general or green raw salads and herbal preparations, where such compounds are abundant.

Effects of Whole Egg Consumption on Carotenoids Absorption from Co‐Consumed, Carotenoids‐Rich Mixed‐Vegetable Salad

Dietary lipid is one of the most effective stimulators of carotenoids (CAT) absorption, but very limited data exist on the impact of endogenous food sources of lipid to enhance CAT absorption. Co‐consuming whole egg which contains lutein (LUT) and zeaxanthin (ZEA), with CAT‐rich foods may increase overall CAT absorption via lipid rich egg yolk. The objective of this study was to assess the effects of egg consumption on CAT absorption from a CAT‐rich, raw mixed‐vegetable salad. Healthy young males (n=16) consumed the same salad (all served with 3g canola oil) with no egg (control, C); with 75g (1½ eggs) of scrambled whole egg (low egg, LE); and with 150g (3 eggs) of scrambled whole egg (high egg, HE) (randomized, crossover design). C, LE, and HE trials included 3g, 10.5g (7.5g from eggs), and 18g (15g from eggs) of total lipid, respectively. Blood was collected hourly for 10h and triacylglycerol rich lipoprotein fractions (TRL) were isolated. Total and individual CAT contents, including LUT, ZEA, α‐carotene (α‐C), β‐carotene (β‐C), and lycopene (LYC) in TRL were analyzed and composite areas under the curve (AUC) were calculated. Total CAT AUC0‐10h in TRL was higher for HE vs. LE and C (125.9±14.1a vs. 46.0±14.1b vs. 15.6±13.6b nmol•L−1•h, p&lt;0.0001). 2 and 5‐fold increases (p&lt;0.001) in TRL AUC0‐10h of LUT and ZEA and 2 to 4 and 4 to 9‐fold increases (p&lt;0.01) in TRL AUC0‐10h of CAT beyond those found in egg such as α‐C, β‐C, and LYC were observed for HE compared to LE and C. These findings support that co‐consuming whole eggs is an effective way to increase both CAT content and absorption of CAT from raw vegetables.Support: American Egg Board; NIH UL1TR001108; Purdue Ingest Behav Res Ctr

Raw vegetable salad consumers in full-service restaurants

Purpose – The purpose of this paper is to identify the profiles of those frequenting full-service restaurants and eating raw vegetable salads, as well as to analyze the influence of socio-demographic variables and of the tendency for social desirability in consumption frequencies. Design/methodology/approach – A non-probabilistic consumer sample (n=630) was interviewed in the city of Campinas, Brazil. Besides the frequency of eating in full-service restaurants and the frequency of eating salads (as a function of the meal type and week day) in this type of restaurant, the survey instrument was also composed by socio-demographic variables and a social desirability scale. To compare data, non-parametric tests were used. Findings – Of the interviewees, 52.3 percent were shown to eat in full-service restaurants at least once a week. The frequency of eating salads in full-service restaurant stood out as being significantly higher (p&lt;0.05) for weekday lunches. Individuals who graduated in the areas of health or food showed a significantly higher frequency for the consumption of salads at weekends. Apparently the social desirability did not influence the responses of the consumers with respect to the frequencies studied. Research limitations/implications – The sample was of a non-probabilistic type, bringing reservations with respect to generalizations. Practical implications – Socio-demographic variables should be considered in elaborating strategies for promoting vegetable salads consumption in restaurants. Health and nutrition education programs can be effective in aiding consumers to choose healthier food in this context. Originality/value – Studies about frequency of salad consumption in restaurants are scarce. The influence of social desirability bias on reported frequency was analyzed in this paper.

COMPOSITIONAL AND MARKETABLE QUALITY OF FRESH-CUT FLORETS OF FOUR SPECIALTY BRASSICAS IN RELATION TO CONTROLLED ATMOSPHERE STORAGE

Brassica vegetables are consumed year-round as raw salad or cooked ingredients. Four Brassica species were selected for this study, broccoli (Brassica oleracea var. italica), broccoli raab (Brassica rapa L.), choisum (Brassica rapa var. parachinensis), and gailan (Brassica oleracea var. alboglabra). While there is abundant information about broccoli, research on gailan, choisum and broccoli raab is very limited. The effect of CA (3% O2 alone or in combination with 7 or 15% CO2, 1% O2 alone or combined with 15% CO2) and air on marketable quality (overall visual, yellowing, discoloration, decay) and chemical parameters (antioxidant activity, chlorophyll, sugar, fermentative volatiles, and ammonia content) during storage at 5°C was evaluated. Products were obtained from a wholesaler, washed in chlorinated water, trimmed into florets and placed in unsealed polyethylene bags that were held in polycarbonate chambers through which humidified air or the controlled atmospheres flowed. Visual quality was evaluated after 0, 8, 12, 16 and 20 days, while chemical parameters were measured after 0, 8, 16 days. Generally, CA treatments did not affect the antioxidant activity, chlorophyll or sugar concentrations in any of the specialty brassicas studied. On the other hand, both ammonia content and visual quality evaluations were affected by atmosphere composition. Florets stored in low oxygen (3% O2) often had the best visual quality but generally all atmospheres maintained better marketable quality than air storage. The 3% oxygen CA improved marketability to about 16 days. Low oxygen delayed postharvest and post-cutting deterioration of florets from all Brassica species, and based on changes in ammonia concentrations, was considered beneficial to maintain quality of fresh-cut brassicas stored at 5°C.

Effect of gamma irradiation on microbial quality of minimally processed carrot and lettuce: A case study in Greater Accra region of Ghana

Abstract The effect of ionizing radiation on the microbiological quality on minimally processed carrot and lettuce was studied. The aim was to investigate the effect of irradiation as a sanitizing agent on the bacteriological quality of some raw eaten salad vegetables obtained from retailers in Accra, Ghana. Minimally processed carrot and lettuce were analysed for total viable count, total coliform count and pathogenic organisms. The samples collected were treated and analysed for a 15 day period. The total viable count for carrot ranged from 1.49 to 14.01 log 10 cfu/10 g while that of lettuce was 0.70 to 8.5 7 log 10 cfu/10 g. It was also observed that total coliform count for carrot was 1.46–7.53 log 10 cfu/10 g and 0.14–7.35 log 10 cfu/10 g for lettuce. The predominant pathogenic organisms identified were Bacillus cereus , Cronobacter sakazakii , Staphylococcus aureus , and Klebsiella spp . It was concluded that 2 kGy was most effective for medium dose treatment of minimally processed carrot and lettuce.

Characterisation of L. monocytogenes strains isolated from salad vegetables

Seventy-one strains of L. monocytogenes isolated from raw salad vegetables consumed in the minimally processed state in Malaysia were characterised by serotyping, random amplified polymorphic DNA-polymerase chain reaction analysis (RAPD-PCR) and antimicrobial susceptibility testing. Based on serotyping, only one strain belonged to serotype 4 while the rest were from serotype 1. RAPD-PCR typing was carried out using two primers, i.e., OPAR-8 and GEN 1-50-09. Based on RAPD-PCR fingerprinting, the strains could be grouped into six composite profile groups and a solitary isolate. The isolates were also evaluated against 16 antibiotics. Excluding nalidixic acid and oxacillin for which L. monocytogenes has natural resistance, the highest prevalence of resistance was against cephalexin. None of the isolates were resistant against imipenem and kanamycin. The multiple antibiotic resistance index (MARI) ranged from 0.06 to 0.63. It was found that most (82%) isolates were susceptible to antibiotics commonly used in veterinary and human listeriosis treatment.

A probabilistic model of gastroenteritis risks associated with consumption of street food salads in Kumasi, Ghana: Evaluation of methods to estimate pathogen dose from water, produce or food quality

With a rapidly growing urban population in Kumasi, Ghana, the consumption of street food is increasing. Raw salads, which often accompany street food dishes, are typically composed of perishable vegetables that are grown in close proximity to the city using poor quality water for irrigation. This study assessed the risk of gastroenteritis illness (caused by rotavirus, norovirus and Ascaris lumbricoides) associated with the consumption of street food salads using Quantitative Microbial Risk Assessment (QMRA). Three different risk assessment models were constructed, based on availability of microbial concentrations: 1) Water — starting from irrigation water quality, 2) Produce — starting from the quality of produce at market, and 3) Street — using microbial quality of street food salad. In the absence of viral concentrations, published ratios between faecal coliforms and viruses were used to estimate the quality of water, produce and salad, and annual disease burdens were determined. Rotavirus dominated the estimates of annual disease burden (~10−3Disability Adjusted Life Years per person per year (DALYs pppy)), although norovirus also exceeded the 10−4DALY threshold for both Produce and Street models. The Water model ignored other on-farm and post-harvest sources of contamination and consistently produced lower estimates of risk; it likely underestimates disease burden and therefore is not recommended. Required log reductions of up to 5.3 (95th percentile) for rotavirus were estimated for the Street model, demonstrating that significant interventions are required to protect the health and safety of street food consumers in Kumasi. Estimates of virus concentrations were a significant source of model uncertainty and more data on pathogen concentrations is needed to refine QMRA estimates of disease burden.

Impact of Traditional Practices on Food Safety: A Case of Acute Toxoplasmosis Related to the Consumption of Contaminated Raw Pork Sausage in Italy

A case of acute toxoplasmosis in an adolescent girl, almost certainly related to the consumption of raw sausage, is described. The girl suffered of fever and weakness and presented a swollen lymph node in the submandibular region. Serology analysis was positive for Toxoplasma gondii and excluded other infections. Further analysis, with avidity test and immunoblot, confirmed the acute toxoplasmosis. She reported that about a month before the appearance of the symptoms, she had eaten a piece of raw sausage while it was being prepared by her father. We analyzed sausage samples prepared from this same batch that had been frozen for later consumption, and they demonstrated evidence of T. gondii DNA when using a specific nested PCR assay. The sausage was prepared from the meat of a pig that had been backyard raised and slaughtered at home, a traditional practice in rural communities in many countries. The tasting of fresh prepared raw sausage is a common practice throughout Italy, and it could be a major cause for toxoplasmosis as suggested by the results of a questionnaire administered in the province of Palermo, Sicily. Contact with cats and, to a lesser extent, raw salad consumption were also referred to as presumptive causes for the symptomatic cases. Two additional cases of acute toxoplasmosis reported during questionnaire administration were alleged to have been caused by the consumption of fresh sausage made with the meat of a pig raised in the yard. Traditional practices in animal farming, and the processing of meat from animals raised in the backyard or meat from wild game animals, might have a big impact on food safety.

A fast, reliable, and sensitive method for detection and quantification of Listeria monocytogenes and Escherichia coli O157:H7 in ready-to-eat fresh-cut products by MPN-qPCR.

In the present work we developed a MPN quantitative real-time PCR (MPN-qPCR) method for a fast and reliable detection and quantification of Listeria monocytogenes and Escherichia coli O157:H7 in minimally processed vegetables. In order to validate the proposed technique, the results were compared with conventional MPN followed by phenotypic and biochemical assays methods. When L. monocytogenes and E. coli O157:H7 were artificially inoculated in fresh-cut vegetables, a concentration as low as 1 CFU g−1 could be detected in 48 hours for both pathogens. qPCR alone allowed a limit of detection of 101 CFU g−1 after 2 hours of enrichment for L. monocytogenes and E. coli O157:H7. Since minimally processed ready-to-eat vegetables are characterized by very short shelf life, our method can potentially address the consistent reduction of time for microbial analysis, allowing a better management of quality control. Moreover, the occurrences of both pathogenic bacteria in mixed salad samples and fresh-cut melons were monitored in two production plants from the receipt of the raw materials to the early stages of shelf life. No sample was found to be contaminated by L. monocytogenes. One sample of raw mixed salad was found positive to an H7 enterohemorrhagic serotype.

English

Passiflora foetida L. belonging to family Passifloraceae is used in Sri Lanka as a traditional medicine in the treatment of diabetes mellitus. This study was designed to examine the antihyperglycemic activity of the aqueous leaf extract of P. foetida in normoglycemic Wistar rats. The extract at a dose of 433 mg/kg (calculated on the basis of the traditional raw salad intake per meal) had a effect not significantly different (p&lt;0.05) for glipizide at a dose of 10 mg/kg, 90 min after the glucose load. Preliminary phytochemical sceening indicated the presence of flavonoids, steroids and saponins as major constituents. Key words: Passiflora foetida, anti-hyperglycaemic effect, glipizide.&nbsp;