Application Note 3.1 pH 3.7 2.6 4.0 5.0 2.5 3.6 3.9 6.8 Continued at the back Food Sauces, and Marinades. Food Safety) Table 1: Some 1: pHTable Values of Common Foods (Source: John E. Rushing, Ph.D., Formulating Dressings, John Rushing, Ph.D., E. (Source: Canned Tomatoes Canned Canned Beans Green Vinegar Lemon Juice Jelly Ketchup Mayonnaise peaches Canned HominyCanned To obtain accurate results, a uniform a uniform results, accurate obtain To should be for maintained temperature buffer the solutions standard and brine samples. The should at be made test between 20-30°C,a temperature the optimum is 25°C. , to measure the pH of brine in canned the canned pH in measure brine of to LAQUAtwin (3) three foods. There are namely pH models meter available, 22, and 33. pocket- These light, pH 11, two allow five meters calibration to sized either using NISTpoints or USA pH buffers. The pH 33 built- has meter sensor measures that temperature in and temperature anddisplays compensation temperature automatic performs that automatic (ATC) feature pH the of buffer the exact to calibration to Refer temperature. the measured at the specifications of model each meter information. more for Method the LAQUAtwinCalibrate pH meter 6.86) buffers (or and 7.00 pHusing 4.01 instructions. manufacturer’s to according Measurement Sample comes the that pipette Using with the of brine an aliquot take the meter, the sample some and place into drops Record the pH and temperature sensor. brine each After testing once stabilized. and thesample, sensor rinse with water dryblot with soft tissue.
spores to to spores
produced in improperly improperly in produced
For brine of canned acid foods, foods, acid canned of brine For must value pH equilibrium the the inhibit to below or 4.6 be botulinum Clostridium of growth Canned Testing Food pH of Brine For For Brine of pH the of resistant heat most the food pathogen microorganisms. canned foods has caused illness canned foods caused has illness Theand death. seal on cans vacuum environment oxygen-free an provides botulinum C. allow will that The anaerobic bacterium Clostridium botulinum Introduction the if toxin, deadly and produce grow canning process not is carried out the botulinum C. Fortunately, properly. The LAQUAtwin pH can be meter used food processorsby or home canners The appropriate pH in the cans is pH the in cans is The appropriate the brines with use of known obtained by known concentrations or of tablets acid compositions to added acid are that cans specified of volumes. The contents theof cans must be then conveniently the pH that below is 4.6 ensure to stirred food particles. all of thein Acids center the 4.6 lower pHused canning to to in but and malic, lactic citric, usually are also glucono-delta-lactone. spores will not grow in high-acid foods high-acid in foods not grow will spores For low-acid foods (pH > (pH ≤ 4.6). resistant these are that spores, 4.6), mustbe temperature, water boiling to the canning process. during killed Continued from the front Results and Benefits Table 2: Acidity and Canning Requirements
Botulism Food acidity is important in preventing botulism, a foodborne illness Acid (pH) Type Canning Method Potential that comes from eating contaminated food with toxins produced by C. botulinum. This fact is used in canning acid foods. Aside from following tested recipes and proper canning methods to ensure that Hot fill* (~190 F) or Boiling Water ≤ 4.6 Acid Food No ° C. botulinum is killed and does not grow in canned food, performing Canner (~212°F) accurate pH measurement using a reliable instrument is also necessary to ensure that the correct pH value of 4.6 or below is attained for food Low Acid > 4.6 Yes Pressure required (~250 F) safety and regulatory compliance. The final equilibrium pH (the pH Food ° of a food product after the food acid is distributed equally throughout the product) must be checked, controlled and documented after the *Hot fill processing is only recommended for licensed food processors. Home canners product has completed the thermal processing step. should use the boiling water canning process. (Source: Numer, Brian. Food Acidity and Safety, FN/Food Safety/2008-01) References 1. Sun, Da-Wen. Thermal Food Processing New Technologies and Quality Issues. 2nd ed. USA: CRC Press, 2012. 2. Numer, Brian. Food Acidity and Safety. FN/Food Safety/2008-01. Utah University. August 2008. 3. Pickle Bill Factsheet. Dairy and Food Inspection Division. Minnesota Department of Agriculture REV 0, 12 AUGUST 2015
pH Meters Lineup pH 11 Meter pH 22 Meter pH 33 Meter
mV mV mV Temp
WATER MICRO 2 PT MICRO 5 PT 0.1 pH WATER MICRO 3 PT 0.01 pH WATER 0.01 pH PROOF VOLUME CAL PROOF VOLUME CAL PROOF VOLUME CAL Features Applications include Flat pH sensor with temperature Fresh water testing; aquarium; compensation offers a reliable and affluent treatment; soil & food quick direct measurement of micro- testing; research laboratories; QC samples from 100 μL. education, etc. Model pH 11 pH 22 pH 33 Measurement principle Glass electrode method Minimum sample volume 0.1 mL (0.05 mL with sampling sheet B) Measurement range pH / mV 0 to 14 pH / ± 650 mV Resolution 0.1 pH 0.01 pH Calibration Two-point Three-point Five-point Accuracy ± 0.1 pH ± 0.01 pH Calibration curves USA / NIST Functions Temperature compensation • IP67 Water/Dust Proof • Auto Hold • Auto Stable • Automatic power off (30 minutes) Display Custom (monochrome) digital LCD Operating temperature/humidity 5 to 40°C, 85% or less in relative humidity (no condensation) Battery life Approx. 400 hours in continuous use with x2 CR 2032 batteries Main Material ABS epoxy Dimensions/Mass 164 mm x 29 mm x 20 mm (excluding projections) /Approx. 50 g (meter only, without batteries, approx. 45 g) Accessories included 2 CR2032 batteries • 1 Pipette • Instruction manual • Quick manual • Storage case • 14 mL Standard solutions (pH 4 & pH 7) Ordering Code 3999960122 3999960123 3999960124
LAQUAtwin Pocket Ion Meters Lineup
pH COND Na+ K+ NO3– Ca2+ Salt EC
Horiba Instruments (Singapore) Pte Ltd 83 Science Park Drive, #02-02A, IMS The Curie, Singapore 118258 HORIBA Group is operating Integrated Management System (IMS) Tel. +65 6908 9660 ISO9001 JOA-0298 / ISO14001 JOA-E-90039 / ISO13485 JOA-MD0010 / OHSAS18001 JOA-OH0068 E-mail: [email protected] http://www.horiba-laqua.com