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Storage Study (storage + study)
Selected AbstractsQUALITY LOSS DURING TOMATO PASTE PRODUCTION VERSUS SAUCE STORAGEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2001RADHIKA K. APAIAH Two studies were conducted to assess the extent of quality changes in tomato processing versus storage. For the processing study, tomato juice was vacuum concentrated into paste at 68C for 300 min (LT) or 85C for 34 min (ST) and samples taken at 5,26 Brix. Reduced ascorbic acid (RAA) degraded sooner during LT than ST, but reached equivalent final concentrations. The particle size decreased and hue angle increased during LT, but not ST. The viscosity decreased more during LT than ST. There was no formation of 5-hydroxymethyl furfural (HMF.) For the storage study, commercial tomato sauce was stored at 4 to 55C for 6 months. RAA degradation and HMF formation during storage were first order with activation energies of 77 and 70 KJ/mole, respectively. The particle size decreased at all storage temperatures, viscosity decreased at 45 to 55C and hue angle increased at 37 to 55C. In general, quality loss of tomato sauce during processing was greater than during storage. [source] Effect of Combined Ozone and Organic Acid Treatment for Control of Escherichia coli O157:H7 and Listeria monocytogenes on LettuceJOURNAL OF FOOD SCIENCE, Issue 3 2006Hyun-Gyun Yuk ABSTRACT: This study was conducted to determine the effects of ozonated water (1, 3, and 5 ppm) alone with different exposure times (0.5,1,3, or5min), and combinations of 3 ppm ozone with 1% organic acids (acetic, citric, or lactic acids) during 1-min exposure for inactivating Escherichia coli O157:H7 and Listeria monocytogenes on lettuce and to observe the regrowth of these pathogenic bacteria on treated lettuce during storage for 10 d at 15°C. Results showed that 5 ppm ozone treatment for 5 min gave 1.09-log and 0.94-log reductions of E. coli O157:H7 and L. monocytogenes, respectively, indicating insignificant reductions compared with 3 ppm ozone treatment for 5 min. Treatment with 3 ppm ozone combined with 1 % citric acid for 1 min immersing resulted in 2.31 - and 1.84-log reductions (P < 0.05), respectively. During storage at 15°C for 10 d after combined treatment and packaging, populations of E. coli O157:H7 and L. monocytogenes increased to approximately 9.0-log colony forming unit (CFU) /g, indicating that this treatment did not have a residual antimicrobial effect during storage. Although the storage study did not show control of these pathogens, the combined ozone-organic acid treatment was more effective in reducing population levels of these pathogens on lettuce than individual treatments. [source] Clarification of Citrus Juice is Influenced by Specific Activity of Thermolabile Pectinmethylesterase and Inactive PME-Pectin ComplexesJOURNAL OF FOOD SCIENCE, Issue 7 2002J. Ackerley ABSTRACT: Thermolabile pectinmethylesterase (PME) from Valencia orange pulp was extracted, partially purified by cation exchange chromatography (IEX), and added to reconstituted orange juice at 2 units/ml. Of the juices that clarified, %T increased, cloud particle size increased and % degree of esterification (DE) decreased in the 15 d storage study. The rate of clarification was most rapid for juices with added PME extracts that never bound Hi-Trap SP and contained 36 and 27 kDa peptide, intermediate for crude extracts of PME not applied to IEX, and lowest for PME extracts that bound Hi-Trap SP and contained 36 and 13 kDa peptide. These results suggest that PME-pectin complexes and low peptides moderate PME activity and juice clarification. [source] Possible nutritional and health-related value promotion in orange juice preserved by high-pressure treatment,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 8 2002Begoña de Ancos Abstract Effects of high-pressure treatment on the orange juice carotenoids (,-carotene, ,-carotene, zeaxanthin, lutein and ,-cryptoxanthin) associated with nutritional (vitamin A) and health-related (radical-scavenging capacity) values were investigated. Various high-pressure treatments (50,350 MPa) combined with different temperatures (30 and 60,°C) and times (2.5, 5 and 15,min) of treatment were assayed. The carotenoid content of the orange juice was analysed by HPLC-UV, the vitamin A value was determined as retinol equivalents (RE) and the free radical-scavenging capacity was evaluated using the DPPH (2,2-diphenyl-1,1-picrylhydrazyl) radical model system. A storage study was carried out at refrigeration temperature (4,°C). High-pressure treatments at 350,MPa produced significant increases of 20,43% in the carotenoid content of fresh orange juice (from 3.99 to 4.78,5.70,mg,l,1). A non-uniform behaviour of high-pressure treatments was detected. An increase in time (beyond 5,min) or temperature (above 30,°C) of treatment did not improve the amount of carotenoids extracted. Owing to better extraction of carotenoids, an increase in vitamin A value from 164 to 238,RE,l,1 (45%) was achieved with the 350,MPa/30,°C/5,min treatment. No correlation was found between the increase in carotenoid amount extracted and the free radical-scavenging activity. © 2002 Society of Chemical Industry [source] | ||||||||||