In developing country like India, a large population of all income and age groups consume freshly squeezed fruit and vegetable juice, but the presence of pathogenic microorganisms in street vended fruit juices has also been reported in various parts of India such as Vishakhapatnam, Mumbai, Amravati, and Nagpur. The source of entry of microorganisms into fresh fruit juices from environment exposure and soil. Therefore, in the last two decades a number of food borne outbreaks associated with unpasteurized fruit juices have been documented in many countries. coli and Salmonella survive in acidic environment of fruit juices due to acid stress response.
įruit juices have pH in the acidic range (<4.5) serving as important barrier for microbial growth. Certain common moulds such as Penicillium sp., Aspergillus sp., Eurotium, Alternaria, Cladosporium, Paecilomyces, and Botrytis have also been reported in spoilage of fruit juices. Among yeasts Pichia, Candida, Saccharomyces, and Rhodotorula are commonly encountered genera responsible for spoilage of juices. The most commonly reported bacterial genera include Acetobacter, Alicyclobacillus, Bacillus, Gluconobacter, Lactobacillus, Leuconostoc, Zymomonas, and Zymobacter. The spoilage caused by microorganisms in juices includes cloud loss, development of off-flavours, CO 2 production, and changes in colour, texture, and appearance resulting in degradation of product. Among these factors, pH and water activity are the most influential factors affecting the spoilage of juices. The critical factors affecting the spoilage of juices include juice pH, oxidation reduction potential, water activity, availability of nutrients, presence of antimicrobial compounds, and competing microflora. Among bacteria, lactic acid bacteria and acetic acid bacteria have been isolated from fruit juices. Penicillium, Byssochlamys, Aspergillus, Paecilomyces, Mucor, Cladosporium, Fusarium, Botrytis, Talaromyces, and Neosartorya are filamentous fungi most frequently isolated from fresh fruits and juices. The major genera include Candida, Dekkera, Hanseniaspora, Pichia, Saccharomyces, and Zygosaccharomyces. Yeasts form the main flora of fruits before processing because of acidic pH. Many microorganisms such as acid tolerant bacteria and fungi (moulds, yeasts) use them as a substrate for their growth. įruit juices contain a microflora which is normally present on the surface of fruits during harvest and postharvest processing which include transport, storage, and processing. Vitamin C is naturally present in juices which are essential for the body to form collagen, cartilage, muscle, and blood vessels. The high potassium and low sodium characteristic of most juices help in maintaining a healthy blood pressure. Extracted juices from fruits contain most substances which are found in the original ripe and sound fruit from which the juice is made. Consumption of fresh juices increased dramatically due to their freshness, high vitamin content, and low caloric consumption. Unpasteurized fruit juice is defined as the product produced by pressing or squeezing of the fruits. Some of the microorganisms detected in these juice samples can cause disease in human beings, so there is need for some guidelines that can improve the quality of fruit juices. niger, Cladosporium, and Fusarium were also observed in tested juice samples.
Candida sp., Curvularia, Colletotrichum, and Acetobacter were observed only in citrus juice samples. Escherichia coli and Staphylococcus aureus were detected in few samples. Among bacteria Bacillus cereus and Serratia were dominant. Aspergillus flavus and Rhodotorula mucilaginosa were observed in the maximum number of juice samples. Yeasts and moulds were the main cause of spoilage of juices. Twenty-five microbial species including 9 bacterial isolates, 5 yeast isolates, and 11 mould isolates were isolated from juices. A total of 30 juice samples were examined for their microbiological quality.
#LIST OF JUICES SERIAL#
In the present study, we have conducted a microbiological examination of freshly prepared juices (sweet lime, orange, and carrot) by serial dilution agar plate technique. They contain essential nutrients which support the growth of acid tolerant bacteria, yeasts, and moulds. Fruit juices are popular drinks as they contain antioxidants, vitamins, and minerals that are essential for human being and play important role in the prevention of heart diseases, cancer, and diabetes.
0 kommentar(er)
