Short Shelf Life (short + shelf_life)

Distribution by Scientific Domains


Selected Abstracts


IDENTIFICATION OF PROCYANIDIN A2 AS POLYPHENOL OXIDASE SUBSTRATE IN PERICARP TISSUES OF LITCHI FRUIT

JOURNAL OF FOOD BIOCHEMISTRY, Issue 3 2007
JIAN SUN
ABSTRACT Postharvest browning of litchi fruit results in short shelf life and reduced commercial value. Experiments were conducted to separate, purify and identify polyphenol oxidase (PPO ) substrates that cause litchi fruit to brown. PPO and its substrate were extracted from the pericarp tissues of litchi fruit. The litchi PPO substrate was purified using polyamide column, silica gel column and Sephadex LH-20 column chromatography. The browning substrate was selected by a 0.5% FeCl3 solution and then identified using a partially purified litchi PPO. Analyses of ultraviolet spectrometry, nuclear magnetic resonance and electrospray ionization mass spectrometry indicated that the PPO substrate was procyanidin A2. The substrate can be oxidized to , -quinones by litchi PPO and then form brown-colored by-products, resulting in pericarp browning of harvested litchi fruit. [source]


ALCOHOLIC BANANA BEVERAGE , ASPECTS IN FERMENTATIVE PRODUCTION

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2009
SUNITA SINGH
ABSTRACT This study quantified fermentative changes in processing alcoholic banana beverage as a result of two factors, namely, sorghum as an ingredient in mix and time period of fermentation, affecting the process in two scales (375 g and 2,900 g) of ingredients mix used. Diluted pulp (with water) from overripe bananas (Musa robusta) mixed with sprouted sorghum grains as ingredients were compared with ingredients without sorghum. The total sugars (reducing and total carbohydrates) were higher when sorghum was not added as an ingredient in initial mix to be fermented. Nevertheless, there was higher utilization of fermentable sugars and carbohydrates in the mix when sorghum was present in both scales of mix studied. The fermentative activities of inoculate as a result of interactive effect of sorghum and time period in the process was attributed to these utilizations. The time factor in fermentation allowed for significant increase in alcohol in the beverage (48 h with 375 g and 68 h with 2,900 g). The beverage obtained with sorghum contained 9.8 g% alcohol at 48 h from 375 g mix and 24.3 g% alcohol at 68 h from the 2,900 g mix of ingredients. These contents were higher as compared to beverage prepared without sorghum: 18.3 g% alcohol at 48 h from 375 g mix and 13.1 g% at 68 h from 2,900 g ingredient mix. The average yields of beverage (with added sorghum) were 54.6% and 57.9%, from 375 g mix batch and 2,900 g mix larger scales, respectively. PRACTICAL APPLICATIONS Banana has a short shelf life after it enters the retail market. The domestic supply in India in 2002 accounted for 20% wastage of bananas as a postharvest loss. The total losses in banana transactions were of the order 13,18% in a single wholesale market of the local city. It was possible to add value of ~48% if these overripe bananas processed into alcoholic beverage. The wasted bananas in domestic supply chain may be source of raw material present in the cycle of marketing itself. Using overripe bananas as the raw material in this study, we could ascertain the product characteristics so obtained after fermentation. These wasted bananas can thus be utilized using modified process detailed herein, if such a technology is readily available. This can replace spurious/illicit drinks in local pockets by using these cheap raw materials available in local abundance. [source]


Review of Hemoglobin-Vesicles as Artificial Oxygen Carriers

ARTIFICIAL ORGANS, Issue 2 2009
Hiromi Sakai
Abstract Blood transfusion systems have greatly benefited human health and welfare. Nevertheless, some problems remain: infection, blood type mismatching, immunological response, short shelf life, and screening test costs. Blood substitutes have been under development for decades to overcome such problems. Plasma component substitutes have already been established: plasma expanders, electrolytes, and recombinant coagulant factors. Herein, we focus on the development of red blood cell (RBC) substitutes. Side effects hindered early development of cell-free hemoglobin (Hb)-based oxygen carriers (HBOCs) and underscored the physiological importance of the cellular structure of RBCs. Well-designed artificial oxygen carriers that meet requisite criteria are expected to be realized eventually. Encapsulation of Hb is one idea to shield the toxicities of molecular Hbs. However, intrinsic issues of encapsulated Hbs must be resolved: difficulties related to regulating the molecular assembly, and management of its physicochemical and biochemical properties. Hb-vesicles (HbV) are a cellular type of HBOC that overcome these issues. The in vivo safety and efficacy of HbV have been studied extensively. The results illustrate the potential of HbV as a transfusion alternative and promise its use for other clinical applications that remain unattainable using RBC transfusion. [source]


Methods for the isolation and identification of Listeria spp. and Listeria monocytogenes: a review

FEMS MICROBIOLOGY REVIEWS, Issue 5 2005
Uta Gasanov
Abstract Listeria monocytogenes is an important food-borne pathogen and is widely tested for in food, environmental and clinical samples. Identification traditionally involved culture methods based on selective enrichment and plating followed by the characterization of Listeria spp. based on colony morphology, sugar fermentation and haemolytic properties. These methods are the gold standard; but they are lengthy and may not be suitable for testing of foods with short shelf lives. As a result more rapid tests were developed based on antibodies (ELISA) or molecular techniques (PCR or DNA hybridization). While these tests possess equal sensitivity, they are rapid and allow testing to be completed within 48 h. More recently, molecular methods were developed that target RNA rather than DNA, such as RT-PCR, real time PCR or nucleic acid based sequence amplification (NASBA). These tests not only provide a measure of cell viability but they can also be used for quantitative analysis. In addition, a variety of tests are available for sub-species characterization, which are particularly useful in epidemiological investigations. Early typing methods differentiated isolates based on phenotypic markers, such as multilocus enzyme electrophoresis, phage typing and serotyping. These phenotypic typing methods are being replaced by molecular tests, which reflect genetic relationships between isolates and are more accurate. These new methods are currently mainly used in research but their considerable potential for routine testing in the future cannot be overlooked. [source]