HANNA INDIA via YOUTUBE 30/06/13 HI99163: Portable HACCP Compliant pH Meter for Meat. BRITISH COLUMBIA INSTITUTE OF TECHNOLOGY - 2014 - Safety and pH Measurements of Sushi Rice in Japanese Restaurants in Burnaby BC, Canada. BRITISH COLUMBIA INSTITUTE OF TECHNOLOGY - 2014 - Safety of Chinese Roast Pork as Determined by the Water Activity of the Skin and Cavity. FOOD CONTROL - 2015 - Influence of pH and temperature variations on vapor phase action of an antifungal food packaging against five mold strains. PEDAK_NL - The influence of water activ ity (aw) in bakery products. INTERNATIONAL CONGRESS ON ENGINEERING AND FOOD (Athens - Greece) - MAI 2011 - Au sommaire: MFS1156 Salmonella survival in low aw environment. WIKIPEDIA - page water activity. Water activity or aw is the partial vapor pressure of water in a substance divided by the standard state partial vapor pressure of water.
In the field of food science, the standard state is most often defined as the partial vapor pressure of pure water at the same temperature. Using this particular definition, pure distilled water has a water activity of exactly one. As temperature increases, aw typically increases, except in some products with crystalline salt or sugar. Higher aw substances tend to support more microorganisms. Bacteria usually require at least 0.91, and fungi at least 0.7. See also fermentation. Formulae WIKIPEDIA - page pH. Hence, pH measurements are important in medicine, biology, chemistry, agriculture, forestry, food science, environmental science, oceanography, civil engineering, chemical engineering, nutrition, water treatment & water purification, as well as many other applications.
The pH scale is traceable to a set of standard solutions whose pH is established by international agreement. Primary pH standard values are determined using a concentration cell with transference, by measuring the potential difference between a hydrogen electrode and a standard electrode such as the silver chloride electrode. The pH of aqueous solutions can be measured with a glass electrode and a pH meter, or indicator. History The concept of p[H] was first introduced by Danish chemist Søren Peder Lauritz Sørensen at the Carlsberg Laboratory in 1909 and revised to the modern pH in 1924 to accommodate definitions and measurements in terms of electrochemical cells. Definition and measurement PROCESS 02/03/10 AwDesigner aide à la formulation P. VULKOV. 3rd Central European congress on food - MAI 2006 - WATER ACTIVITY CONCEPT FOR SAFETY FOOD STORAGE. Appl. Environ. Microbiol. February 2007 vol. 73 no. 3 997-1001 Role of Branched-Chain Fatty Acids in pH Stress Tolerance in Listeria monocytogenes▿
+ Author Affiliations In alkaline conditions, Listeria monocytogenes cells develop higher proportions of branched-chain fatty acids (FAs), including more anteiso forms.
In acid conditions, the opposite occurs. FOOD PRODUCTION 19/12/06 Software ties product location to temperature and humidity data. Sybase says its RFID Anywhere 3.0 breaks new ground with the delivery of a context-aware location information system, allowing companies to track other data, such as temperature, at a particular location.
The updated version of the software includes new support for real-time location systems and active RFID technology, as well as an increased ability to track mobile RFID and forklift readers. RFID has long been touted as the future of logistics for all companies by allowing retailers and suppliers to track goods throughout the supply chain. One of the key areas of concerns for early adopters of RFID is how to make intelligent business decisions based on the massive amount of data created byRFID, said Curtis Price, programme director at IDC, an analyst. "The enhancements made to Sybase's RFID software platform address this issue and provides an increased level of value by combining RFID into an intelligent sensor network,"Price stated.
UNIVERSITY OF MASSACHUSETTS 02/02/1999 Calculating water activity of dry food mixtures using Mathematica or Excel. FOOD SAFETY MAGAZINE - FEV/MARCH 2001 - Water Activity’s Role in Food Safety and Quality. INSIDE MICROBIOLOGY | February/March 2001 By Anthony J.
Fontana, Jr., Ph.D. Monitoring aw is a critical control point for many food industry operations. FOOD SAFETY MAGAZINE - OCT 2007 - Water Activity: A New Food Safety Tool. SANITARIAN’S FILE | October/November 2007 By Robert W.
Powitz, Ph.D., MPH. NSW FOOD AUTHORITY - Shelf stable acid preserved foods - Factors affecting the shelf stability of acid foods Condiments, sauces and salad dressings. FSAI 03/12/14 Shelf-life Determination. FDA - Guidance for Commercial Processors of Acidified & Low-Acid Canned Foods. FDA 06/04/84 Water Activity (aw) in Foods. Date: 4/16/84 Number: 39 Related Program Areas: Foods ITG SUBJECT: WATER ACTIVITY (a w) IN FOODS The water activity (a w) of a food is the ratio between the vapor pressure of the food itself, when in a completely undisturbed balance with the surrounding air media, and the vapor pressure of distilled water under identical conditions.
A water activity of 0.80 means the vapor pressure is 80 percent of that of pure water. The water activity increases with temperature. The moisture condition of a product can be measured as the equilibrium relative humidity (ERH) expressed in percentage or as the water activity expressed as a decimal. Most foods have a water activity above 0.95 and that will provide sufficient moisture to support the growth of bacteria, yeasts, and mold. The bacterial cell can only transfer nutrients in and waste materials out through the cell wall. Two basic methods can be used to obtain the constant temperature sorption curves. ENVT - Présentation : Ecologie microbienne des aliments.