A 2019 Outbreak Investigation of Hepatitis A Virus Infections in the United States Linked to Imported Fresh Blackberries

Globally, hepatitis A virus (HAV) is one of the most common agents of acute viral hepatitis and causes approximately 1.4 million cases and 90,000 deaths annually despite the existence of an effective vaccine. In 2019, federal, state, and local partners investigated a multi-state outbreak of HAV infections linked to fresh blackberries sourced from multiple suppliers in Michoacán, Mexico. A total of 20 individuals with outbreak-related HAV infection were reported in seven states, including 11 hospitalizations, and no deaths. The Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC), and Nebraska State and Douglas County Health Departments conducted a traceback investigation for fresh blackberries reportedly purchased by 16 ill persons. These individuals reported purchasing fresh blackberries from 11 points of service from September 16 through 29, 2019 and their clinical isolates assessed through next-generation sequencing and phylogenetic analysis were genetically similar. The traceback investigation did not reveal convergence on a common grower or packing house within Mexico, but all of the blackberries were harvested from growers in Michoacán, Mexico. FDA did not detect the pathogen after analyzing fresh blackberry samples from four distributors, one consumer, and from nine importers at the port of entry as a result of increased screening. Challenges included gaps in traceability practices and the inability to recover the pathogen from sample testing, which prohibited investigators from determining the source of the implicated blackberries. This multi-state outbreak illustrated the importance of food safety practices for fresh produce that may contribute to foodborne illness outbreaks.

Development of antifungal biopolymers based on dynamic imines as responsive release systems for the postharvest preservation of blackberry fruit

This study describes the synthesis and reversibility of Schiff bases from chitosan and bioactive compounds, and their application in the antifungal packaging of fruit. Imine bonds between primary amine groups of chitosan and carbonyl groups of antifungal aldehydes were synthesised and their reversibility was assayed in an aqueous medium under different acidic conditions. The mechanism of action of the dynamers is based on the hydrolysis of imine bond and the release of the active agent. The new films were effective at inhibiting the growth of Penicillium expansum and Botrytis cinerea, and their effectivity depended on the degree of hydrolysis achieved which was greater when the bonds were hydrolysed in a mild acidic medium. A double bottom cylindrical tray was used for the responsive antimicrobial packaging of blackberries. The package extended shelf-life of berries from 3 to 12 days without causing phytotoxic effects on the fruit being safe for human consumption.

Effect of starch-beeswax coatings on quality parameters of blackberries (Rubus spp.)

There is increased interest in berry fruits due to health benefits, and maintenance of fruit quality for longer periods of time has been a priority. We previously found that starch based coatings applied on raspberries was associated to volatile compounds production due to anoxic conditions. The objective of this work was to design more hydrophobic coatings with reduced thickness. A starch-beeswax dispersion containing 2 % (w/v) modified tapioca starch added with either 0.5 or 1.0 % (w/v) beeswax microparticles was produced, and used for spray coating freshly harvested blackberries (Rubus spp.). Coatings were air dried, packed in plastic trays and stored up to 16 days at 4 °C and 88 % relative humidity. Storage quality parameters such as hardness, respiration rate, anthocyanins content, total phenols, color changes and weight loss were evaluated. We did not find Interactions among coating ingredients, and incorporation of beeswax reduced moisture transfer rate. Coatings did not occlude the stomata and apparently did not over-hydrate the cuticle. This characteristic allowed appropriate gas exchange (O2 and CO2), and reduced accumulation of volatile compounds associated to fermentative metabolism. Respiration rates were 4.207 ± 0.157, 4.557 ± 0.220 and 4.780 ± 0.050 mmol CO2 kg(-1) h(-1) for control, 0.5 and 1 % of wax content in coatings, respectively. However, ethylene production increased throughout storage time along with beeswax concentration, indicating stressful conditions for the fruit. This trend appears to be related with changes in total phenols and anthocyanins during storage. Edible coatings based on starch and hydrophobic particles should be reformulated to maintain quality of stored berry fruits.

Edible berries: bioactive components and their effect on human health

The importance of food consumption in relation to human health has increased consumer attention in nutraceutical components and foods, especially fruits and vegetables. Berries are a rich source of a wide variety of non-nutritive, nutritive, and bioactive compounds such as flavonoids, phenolics, anthocyanins, phenolic acids, stilbenes, and tannins, as well as nutritive compounds such as sugars, essential oils, carotenoids, vitamins, and minerals. Bioactive compounds from berries have potent antioxidant, anticancer, antimutagenic, antimicrobial, anti-inflammatory, and antineurodegenerative properties, both in vitro and in vivo. The following is a comprehensive and critical review on nutritional and non-nutritional bioactive compounds of berries including their absorption, metabolism, and biological activity in relation to their potential effect on human health.