FTIR Analysis at Harvest and Fermentation€¦ · • FTIR is a technology that passes IR light...

FTIR Analysis at Harvest and Fermentation

Gusmer Enterprises May, 2015

by Calvin Watkins Nate Starbard

Contents • Background of FTIR • Overview of FOSS FTIR platforms

• WineScan • OenoFoss

• Applications during vinification, harvest, fermentation • Grape Health / Rot • Ripeness • Crush Pad • Fermentation

What is FTIR? • FTIR is a technology that passes IR light through a sample. • As this passes through the sample, portions light spectrum are absorbed by

the molecules of the sample. What isn’t absorbed is collected as IR interferograms and sent to the computer for analysis.

What is FTIR? • These readings are run through a series of

calculations that then provide a result on the computer monitor.

• FOSS’ robust calibration based on 10’s of thousands of reference analyses and decades of work

WineScan • The WineScan FTIR platform has been performing the bulk of routine wine

analysis for over 20 years (>1100 units in operation) • Most outsourced analytical labs • Major university and research programs • Almost every major corporate winery (some running as many as 15

WineScan units)

WineScan

WineScan • New FT-2 is not the original FT-120

• Pre-package calibrations ready to go out of the box • Building on OenoFoss success Gusmer now

handles WineScan line fully • Additional parameters people have created:

methanol, anthocyanins, succinic acid, port wine parameters, ethyl acetate and more

WineScan Out of the Box

OenoFoss • The OenoFoss is the latest

FTIR based wine analyzer to be introduced by FOSS.

• Approx. 700 units in operation

• The OenoFoss has lower entry costs than the WineScan, no operating costs, and continues to provide fast accurate results.

• Fewer analyses, no creation

Cuvette Space Motor

Opening Lid

Upper Window

Lower Window

Detector Unit IR-Detector

IR-Beam

Benefits of OenoFoss • Analytical Speed –

• 2 minutes per sample per test battery • Accurate and Repeatable Analysis –

• Results guaranteed to be within Foss specifications • Same results regardless of operator

• Uncomplicated • If you can use a pipette you can use an OenoFoss

• No Consumables, Wear Parts

Harvest and Fermentation Specific Applications for FTIR

Platforms

Grape Health • Visual inspection proven to not be accurate to eventual wine quality

when it comes to rot • Glycerol, Gluconic, Volatile Acidity, Ethanol

• Often all must be considered – a high glycerol, for example, with the other parameters low will not cause issues

• Grape soundness indicators/indexes that account for all (sometimes + glu/fru ratio)

• Typical threshold for glycerol, gluconic, ethanol 1 g/L; for VA 0.2 g/L • Studies show that visual % of grape rot is less of an impact to wine than

duration of grape rot • Glycerol and gluconic can vary by up to 400%, based on time of

infection, at the same % rot • Temperature therefore also important

Infections

• Microbes such as botrytis preferential to glucose • Changes in glucose / fructose ratio are an

indication of degree and length of infection

Grape Maturity/Ripeness • Brix should not be the only indication

• Ratio of amino acids to ammonium also an indication of ripeness in parallel with brix

• Nitrogen containing compounds critical to downstream processing and eventual wine quality • Total utilizable N does not

necessarily increase with ripening but easily utilized N from amino acids does increase

• Negative sensory characteristics attributed to unripeness at least partially due to N sources

• Amino acids important for formation of higher alcohols and esters

Phenolics • Folin C in WineScan ; OD 280 in OenoFoss • Why measure total phenols (tannins +

anthocyanins) • Determine optimum time to harvest • Aging potential • Responsible for color and taste

• Wet chemistry (Adams-Harbertson Assay) one of the longest, most difficult procedures

Analysis @ Crush Pad • Avoids totally relying on visual inspection • Quantitative and defined parameters for quality

and thus payment • Extremely accepted in EU (more co-ops)

• Instant results for each unit (bin, truck) of incoming grapes

• Allows for documentation

Fermentation Optimization • Of course you can closely monitor residual

sugar, volatile acidity, tartaric and malic acids • Closely monitor nitrogen compounds

• Addition of nutrients • Effectiveness of and “good stuff” in nutrients

• Correct environment for the dominance of chosen fermentation strain

• Rack the wine off lees sooner

Stuck Fermentations • Yeast assimilable nitrogen, N compounds • Independent glucose and fructose

measurements – not just total RS • Adjust temperature according to analysis • Watch VA (less than 0.6 g/L) for bacteria

infection and ability for yeast re-start • Lysozyme or RO

ML Fermentation • Selection of strain and accompanying nutrients • Important to monitor: acidity, pH, alcohol

• SO2 (WineScan only) • Monitor usage/completion of malic acid

• Pace of ML fermentation before it gets stuck

Value of Ownership • Cost pay back is often enormous

• Smaller wineries reduce outsourced testing fees • Often spend $15-25K/yr on outsourcing before bringing a lab in-house • Shipping time and costs

• Larger wineries become time efficient, reduce spend on chemicals, footprint of lab and other equipment required

• Increased sampling time frame • Increase sampling sizes

• Every barrel vs a sampling (especially barrel ferment) • Instant results

• Stuck fermentations, additions, on the fly adjustments • More knowledge !!

Thank you,

Questions?