Application Notes

CONTRIBUTORS:

New Food, Volume 17, Issue 6, 2014 60 www.newfoodmagazine.com

61 Shimadzu

62 Carl Zeiss

63 Ocean Optics

64 Bruker Optik

IBC Biotage ©

Afr

ica

Stud

io /

Shut

ters

tock

.com

nf614 App Notes lead_Layout 1 09/12/2014 13:34 Page 1

Figure 1: Target analytes at 0.05 mg/kg in apple matrix

Food safety laboratories involved in pesticide residue monitoringtypically employ a multi-residue LC-MS/MS method for thequantification of an ever increasing list of target pesticides. However, theanalysis of several highly polar pesticides is extremely challenging due totheir low mass, amphoteric character and lack of chemical groups thatmight facilitate their detection. For this reason, single residue methods orsmall group specific methods are often utilised to analyse thesecompounds, in some cases including the use of pre- or post-columnderivatisation. In this study we present two methods developed for theanalysis of a wide range of polar pesticides using the Shimadzu LCMS-8050. All of the compounds included in this study were polar,characterised with LogKow < 1. The most polar compounds being thecationic quaternary ammonium herbicides diquat (LogKow -4.6) andparaquat (LogKow -4.5). Several of the compounds also have a lowmolecular mass, for example trimesium (77 g/mol), amitrole (84 g/mol)and ETU (102 g/mol).

Sample preparationSamples were extracted according to the EURL-SRM QuPPemethodology. Linearity was evaluated from 0.005 – 0.2 mg/kg usingdeuterated internal standards for calibration.

UHPLC-MS/MSExtracts were analysed on a Nexera-X2 UHPLC system and coupled to aLCMS-8050 triple quadrupole mass spectrometer. Analysis was carriedout using selected reaction monitoring acquiring two to five transitionsfor each compound in ESI +/-. Two methods were developed to quantifyall compounds; the LC conditions are listed below:

Results

Conclusionn Two methods were developed for a range of challenging highly

polar pesticides. n All compounds were quantified at 0.005 mg/kg with linearity R2 > 0.997

Application Note Shimadzu

For further information, please visit:www.shimadzu.eu

www.newfoodmagazine.com 61 New Food, Volume 17, Issue 6, 2014

Multi-residue analysis of highly polarpesticides in food safety by LC-MS/MS

Table 1: LC conditions for methods 1 and 2

Table 2: Target compounds summary

Figure 2: Example calibration curves

■ David R. BakerShimadzu, Manchester, UK

■ Mikaël LeviShimadzu, Marne-La-Vallée, France

■ Eric CapodannoPhytocontrol, Nimes, France

Method 1

Method 2

ParaquatR2=0.9995

GlyphosateR2=0.9983

nf614 Shimadzu App Note_Layout 1 09/12/2014 11:16 Page 1

ZEISS was one of the first companies to develop spectrometers foroperation in the farming industry, for example on harvesting machines.The spectrometer systems are used under really harsh conditions andare able to deliver precise results despite fluctuating temperatures,vibrations and shocks. The real challenge for the food industry is to offera product with consistent quality using raw materials which arethemselves subject to ongoing natural fluctuation. To ensure aconsistent process flow, the entire process must be monitored at allstages. Starting with quality analysis of raw materials, ongoingmonitoring is required at stages throughout the process and for finalinspection of the finished product. The monitoring programme can also

support process optimisation. An additional benefit of monitoring is tocontrol the residual materials in order to determine the value of the‘waste’ in case of re-utilisation.

The commonality of all in-line sensors from ZEISS is the software.The InProcess software enables the user to control severalspectrometers at the same time. In addition to performance, ease of useis the primary purpose of the software strategy. Owing to its clear format,it is intuitive to handle. The graphic user interface, which comprises icon menus, has been optimised for touch-screens and seems simple even at first sight. The completely new InProcess software

allows simple configuration of the measurement process. In addition,the software allows the use of calibrations from all standard chemometric software packages.

To achieve the highest operational standard, the sensor system hasto be connected to the control system of the production line. ZEISSenables its sensors to communicate with the production line on OPCbase with the software tool ProcessLinker.

Conditions and parameters vary from case to case and applica-tion. We face liquids, pasty goods or solids and conditions in-between. We have conditions from extremely cold to hot and extreme humidity.Therefore, the measurement hardware has to deal with these conditions,survive and deliver reliable results. For almost all the applications there is a sensor from ZEISS that fits perfectly in the environment on site. The integration and calibration work can be done by ZEISS service staff,ZEISS partners or by the customer itself.

Carl Zeiss Microscopy GmbH Application Note

For further information, please visit:www.zeiss.com/spectral

www.newfoodmagazine.com 62 New Food, Volume 17, Issue 6, 2014

Corona process is a combined NIR/VIS spectrometer which is able to measureingredients and colour simultaneously. The distance to the sample can varyfrom 80 mm – 600 mm so that no direct contact to the product is required. All protection standards and hygienic needs are met.

Corona extreme is the most robust NIR sensor on the market. The sensor cancome with an ePC so that the system works independently as a smart sensor tobe integrated for instance in SPS controlled machinery.

CORONA PLUS REMOTE is the solution for constricted room conditions. A broadchoice of spectrometers and fibre linked measurement probes makes thissystem very flexible and adaptable.

With the MCS 600 ZEISS offers a high-end modular spectrometer system whichcan be perfectly matched with the measurement task. All kinds of probes can beconnected via SMA fibre connectors.

In-line process control:the key to more efficiency■ Ria Sachse, Ralf Vogt Carl Zeiss Microscopy GmbH, Optical Sensor Systems

nf614 Carl Zeiss App Note_Layout 1 09/12/2014 10:39 Page 1

Scientists and food researchers have created a device that allows usersto monitor the intricacies of cheese production. Using data collectedwhile measuring backscattering of cheese using an Ocean Opticsspectrometer and light source, the researchers have developedalgorithms to predict the optimal cutting time, fermentation endpoint,whey fat losses, cheese yield and curd moisture of various cheeses.

Cheese-making has long been an art, but it is now becoming ascience as well. The process of cutting coagulated milk in vats causesmoisture to be released from the curd in the form of whey, and it is thesize and moisture of that curd that plays a large role in determining the quality of the finished product. Monitoring the process of curdsyneresis is difficult, however, as most methods are disruptive to thecheese-making process.

Researchers from University College, Dublin, Ireland; the University ofKentucky in Lexington, USA; and the Moorepark Food Research Center inCork, Ireland, have developed an online Vis-NIR optical sensor to monitorvarious characteristics of the cheese-making process. This type of onlinemonitoring of coagulation and syneresis, along with the application ofspecial algorithms to the data, allows instant feedback, improving theconsistency of curd moisture and texture from batch to batch.

ExperimentThree experiments, each comprising unique experimental variables anddesigns, were undertaken in this study. In each experiment a unique mixof whole milk, skim milk powder, distilled water, cream and calcium

chloride (firming agent) was prepared. The milk was heated to atemperature of 32 +/- 0.1 °C. In each experiment, the cutting blades werereplaced after gel cutting and stirring at a certain speed for 4 minutesover the course of syneresis. Then curd and whey samples weremeasured for fat content.

The syneresis sensor comprised a tungsten halogen light source, anoptical fibre, a vertical polariser, and a glass window. Backscattered lightwas collected over a large area through the glass window. Reflected light was then transmitted through a second fiber and a collimating lensfocused the scattered light onto an optical fiber and transmitted it to theHR2000CG-UV-NIR miniature spectrometer.

ResultsRaw spectra obtained from the online sensor during syneresis is shownin Figure 1.

ConclusionsThe online sensor was able to predict whey production and fat content inwhey. In general terms, the light backscatter sensor will work in differentcheese production plants but a model developed at the laboratory level or for a specific plant may need to be adapted to the needs of thatplant, depending on the range of milk composition, cheese type and vat design in use.

ReferenceValidation of a curd-syneresis sensor over a range of milk compositionand process parameters. Mateo, M.J. et al. Journal of Dairy Science ,Volume 92 , Issue 11 , 5386 – 5395.

SourceSegments of this material were derived from open-access mediapublished in the Open Access Journals section of ScienceDirect.com.

Application Note Ocean Optics

For further information, please visit:www.oceanoptics.com

www.newfoodmagazine.com 63 New Food, Volume 17, Issue 6, 2014

Backscatter Analysis in Cheese Production

Imag

e Cr

edit:

Dai

ryRe

port

er.c

om

Image Credit: Manuel Castillo, Ph. D.,Universitat Autonoma de Barcelona, Spain

Figure 1: Vis-NIR reflectance spectra showing the effect of (a) curd-stirring speedand (b) fat level in milk

Curd Synerisis Optical Sensor

nf614 Ocean Opticsd App Note_Layout 1 09/12/2014 11:35 Page 1

Bruker Optics announced the release of the new networking softwareONET. The software is a server application accessed via a browser-basedweb interface (WebUI), allowing to set up, administrate and control anetwork of FT-NIR instruments from a central remote location anywherein the world. All data measured on local spectrometers are stored firstlocally and replicated to a ONET database for central access.

Nevertheless, all data and required files are still available locally,which allows the analysis of samples at any time even when the networkis temporarily disconnected.n Efficient remote supportn Utilisation of centralized expertisen Full control of local setup n Simplified local workflows n Cost savings by ensuring system integrity

FT-NIR spectroscopy has become extremely important for quality controltasks due to its ease of use for routine operators. Method developmentand the management of large spectrometer pools can however bechallenging. With the continuous demands for cost savings, it is virtuallyimpossible to have NIR expertise in every single laboratory or productionsite. Therefore the need for a central administration, methoddevelopment and system maintenance is essential.

With ONET, all methods can be centrally set up and adapted,reducing the need for local expertise and training. Procedures and results

are harmonised and based on the same setup and calibrations. Audittrails guarantee the full transparency of products, methods and operatorinteractions, assuring the integrity of the data at all times.

Calibration updates can be rolled out to all instruments inside thecompany network or specific versions can be assigned to a limitednumber of spectrometers. This allows a global network with localadjustments if required.

The instrument performance can be monitored remotely at all times, and system tests can be defined and carried out according toscheduled routines.

Benefits:n Full control of all instruments by centralised specialistsn Effective remote support reduces travel expensesn Harmonized calibration development and central validation ensure

reliable resultsn Operating instruments is no longer depending on local expertisen Software complexity at instrument level is eliminatedn Centralised result storage allows a global view on operations from

raw materials to finished products.

Key Features:n Global user management n Central data pooling and accessn LIMS connection to central data basen Complete audit trail logging of all activities n 24h timeout for maintenance/servicen Supported languages: English, Chinese, French, German, Spanish.

Bruker Optics Application Note

For further information, please visit:www.bruker.com/onet

www.newfoodmagazine.com 64 New Food, Volume 17, Issue 6, 2014

ONET – Bruker’s new Software for Administrationof large FT-NIR Spectrometer Networks

Figure 1: Bruker ONET Software for the setup, administration and control oflarge FT-NIR spectrometer networks

Figure 2: All spectrometers inside the network and their current statuses are listed

Figure 3: The User Management of ONET allows a dedicated administration of user rights

nf614 Bruker Optics App Note_Layout 1 09/12/2014 11:15 Page 1

Extraction ProcedureFormat:ISOLUTE® SLE+ 1 mL Sample Volume Columns, part number 820-0140-CSample pre-treatment:Add 10 mL water to 1g crushed sample (previously spiked with 13C3acrylamide internal standard), and mix for 1 hour. Centrifuge, andremove a 0.65 mL aliquot of the aqueous layer, taking care not to includeany of the thin upper oil layer.Sample loading:Load pre-treated sample (0.65 mL) onto the ISOLUTE SLE+ column. Applya pulse of vacuum or positive pressure to initiate flow. Allow the sampleto absorb or 5 minutes.Analyte Elution:Elute with ethyl acetate: tetrahydrofuran, (1 : 1, v/v, 2 x 2.5 mL) and allow to flow under gravity into tubes containing 2 µL ethylene glycol ineach well. Apply vacuum or positive pressure to elute any remainingextraction solvent.Post Elution:Dry the volatile constituents of the eluate in a stream of air or nitrogen.Reconstitute in water (200 µL).

HPLC ConditionsInstrument: Waters AcquityColumn: Phenomenex Hydro 4µm 50 x 2mm C18 column with a C18 guard cartridge and on-line filterMobile Phase: A: 0.1% formic acid in water; B: 0.1% formic acid in methanol

Flow rate: 0.3 mL min-1 Injection volume: 10 µLGradient: Initial 100 % A, hold till 0.6 minlinear ramp to 100 % B over 0.25 min (0.85 min), hold 1.65 min (2.5 min)linear ramp to 100 % A in 0.01 min (2.51 min), hold 2.49 min (5 min)Column temperature: 40 °CSample temperature: 20 °C

MS conditionsIons were selected in order to achieve maximum sensitivity usingmultiple reaction monitoring.Instrument: Waters Quattro PremierIonization mode: ES+Desolvation temp.: 450 °CSource temp.: 120 °C

Results and conclusionA method has been developed which measures acrylamide from achallenging matrix at highly sensitive levels. Despite acrylamide being a relatively polar molecule excellent separation was demonstratedbetween this and matrix interferences on the SLE+ material. The methodhas a good recovery (90%), low %RSD (