An approach for developing quantitative risk-based microbial standards for fresh produce

A key objective of the Good Agricultural Practices (GAP) program is to reduce the potential for produce to become contaminated with microbial pathogens, such as through irrigation water. Without microbial standards, however, it is impractical to decide whether there is a need to disinfect, a need to institute watershed protection programs, or a need to institute post-harvest disinfection regimes. To develop such standards, quantitative microbial risk assessments can be performed using pathogen monitoring data for produce. This paper presents an approach which can be used towards the application of a risk assessment framework to developing microbial standards for fresh produce. Risks of infection are estimated using typical monitoring data of Salmonella detected on carrots and assuming various scenarios of the likelihood of an individual consuming a contaminated serving of carrots in a given year. Estimated annual risks of infection range from 2.20 × 10^-5 to 2.16 × 10^-3, assuming 1% and 100% of an individual's carrot servings are contaminated, respectively. In addition, critical factors are identified which need to be incorporated in such a risk assessment approach as well as their impact on risk estimates to provide growers with benchmarks which may be targeted to reduce health risks.     

Carrot man: a case of excessive beta-carotene ingestion

In this case report, the authors describe a 48-year-old male who complained to his primary care physician of abdominal discomfort and yellow/orange skin discoloration. Physical examination was normal except for some mild mid-abdominal discomfort (no observed skin color changes). An abdominal CT scan indicated a colon that was full of stool. Laboratory studies indicated elevated liver enzymes. Upon further questioning, the patient reported ingesting 6-7 pounds of carrots per week to facilitate his dieting effort. The patient was diagnosed with constipation, hypercarotinemia, and possible vitamin A toxicity. Following the cessation of excessive carrot ingestion, his liver enzymes normalized within 1 month.     

Evaluation of quality,phenolic and carotenoid composition of fresh-cut purple Polignano carrots stored in modified atmosphere

Purple Polignano carrot is a traditional Italian landrace cultivated in Apulia region rich in antioxidants and with a high nutritional value. On the other hand, these carrots showed a high perishability. The postharvest behaviour of fresh-cut purple Polignano carrots stored in open bags (AIR) or passive modified atmosphere (pMA) was studied, analysing the main qualitative parameters and the polyphenols and carotenoids profile. The storage in pMA allowed to preserve visual quality and respiration rate better than the storage in AIR. Polyphenols (hydroxycinnamic acids, their derivatives and anthocyanins) increased during storage of about 249 % in samples stored in pMA and of about 306 % in those stored in AIR at 4 °C during the first 4 days of storage, respect to fresh carrots. Instead, carotenoids mean content in carrots just after harvest (6.28 ± 0.48 mg kg^-1 fw) did not change significantly during storage at 4 °C (both in AIR or pMA). According to our results, pMA resulted a valid solution to cold store fresh-cut purple Polignano carrots until two weeks, preserving quality and nutritional value.     

Evaluation of different coloured carrot cultivars on antioxidative capacity based on their carotenoid and phenolic contents

We compared five new carrot cultivars with a conventional cultivar in consideration of their content of carotenoids, phenolics and according antioxidative capacity. We chose the following cultivars: orange, white, yellow, red, solid-coloured purple and purple with an orange core. Examinations were conducted over two cultivation periods (2003 and 2004). The white, yellow and solid-coloured purple cultivars showed quite low contents of carotenoids, but the solid-coloured purple contained most phenolic compounds. The red cultivar was the only that contained lycopene. The content of carotenoids varied slightly between the two years; α-carotene showed noteworthy differences in the orange cultivar and the purple cultivar with an orange core. The higher α-carotene content resulted in a higher antioxidative capacity. Also, the lycopene content in the red cultivar was higher in 2004 than in 2003, which again lead to an increased antioxidative capacity. In the case of phenolics, higher values were found for the purple-coloured cultivars in 2004, which only in the case of the purple cultivar with an orange core, however, led to a higher antioxidative capacity.