Techniques for the Evaluation of Microbiological Quality in Honey

The aim of this chapter is to describe the most commonly used techniques to evaluate the microbiological characteristics of honey for the purpose of identifying its contaminant flora, its significance and its control in this type of food. Honey is a product that is rich in simple sugars, minerals, vitamins and bioactive compounds and possesses an antimicrobial activity of great significance for human health. However, as it has physical and chemical properties that are unfavourable for the proliferation of micro-flora, honey can contain a large population of microorganisms from two sources of contamination—the first primarily represented by pollen, the digestive system of the bee, dust, air and the flower itself; and the second as the result of negligence and the absence of good health practices during handling and use; for example, placing honey in wooden beehives directly on the floor or the use of improperly washed honey extraction equipment, rather than equipment based on the oxidizable material, or using very dark honeycombs and storing the honey for long periods in wooden beehives. As honey is a natural product, the risks inherent to the lack of industrial processing, such as pasteurization and strict microbiological quality control, are often overlooked

Antifungal Potential of Hibiscus Tea and Fermented Kombucha

Kombucha is a beverage fermented by a symbiosis of bacteria and yeast from teas. Secondary fermentations can be made using vegetables, such as hibiscus for example. In addition to providing a different flavor, the kombucha fermented with hibiscus can provide functional properties such as antimicrobial and antioxidant action. Botrytis cinerea causes gray rot in fruits and is difficult to control due to resistance to chemicals. The objective of this work was to evaluate the antifungal activity of the 1st fermentation of kombucha (F1), the 2nd fermentation of kombucha with hibiscus (F2H) and hibiscus tea against the fungus Botrytis cinerea for a possible alternative for fungal control in strawberries. B. cinerea was inoculated in PDA medium at concentrations of 50 %, 25 %, 12.5 %, and 6.25 % of hibiscus tea and fermented kombucha and evaluated after seven days for mycelial growth, verified by its diameter. PDA without added tea or kombucha was used as a control. Strawberries were steeped in an aqueous solution of hibiscus tea and fermented into kombucha. The results showed inhibition of the mycelial growth of B. cinerea in the media with concentrations of 50 % and 25 % of kombucha (F1 and F2H) and hibiscus tea, where the inhibition for F1 was 88.9 % and 46.7 %. For F2H, it was 58.9 % and 20 %. And for hibiscus tea, it was 21.1 % and 12.2 %, respectively. When these pure compounds were applied by immersion on strawberries and stored at 15 °C, there were signs of reduced external deterioration, with hibiscus tea showing better control

Control of fungal spoilage in strawberries using crude plant extracts against the fungus <i>Botrytis cinerea</i>

The study evaluated the conservation of strawberries treated with crude plant extracts (barbatimão, sibipiruna, guarana, and catuaba) against fungal deterioration and physicochemical characteristics. MIC of 0.125; 0.0156; 0.25 and 0.0312 g/mL were found for barbatimão, sibipiruna, guaraná and catuaba, respectively, against B. cinerea. Treated samples showed no fungal deterioration during 11 days. Analyzes of weight loss, soluble solids, titratable acidity, and pH variation were performed. Sibipiruna showed lower values ​​of mass loss, and the greatest occurred for the catuaba extract. Barbatimão did not change soluble solids and stood out with catuaba in the color parameters L and a*. Small changes in pH were observed with time. Soluble solids maintained values ​​between 6.47 oBrix and 9.90 oBrix for catuaba and sibipiruna extracts at zero and six days. Principal component analysis did not show a strong correlation between the variables. The extracts become alternatives for strawberry conservation, increasing conservation and maintaining physicochemical characteristics.</p