The Lab Side: Peroxide, UV Indices, Phenolics

Introduction

Sensory notes tell the story; lab metrics give it numbers. Peroxide value, UV absorption indices and total phenolics help you read handling, freshness and stability without drowning in jargon.

Peroxide Value: The First Trace

Peroxide tracks early oxidation. Lower, coherent figures suggest oxygen was well-managed from harvest through bottling. It never rules alone; pair it with sensory and other markers.

UV Indices: K232 and K270

UV absorption scans oxidative byproducts with sensitivity. K232 often reflects primary products; K270 secondary ones. Reading them together offers a functional view of shelf stability. Spikes call for a look at storage and filtration choices.

Total Phenolics: The Backbone of Energy

Phenolics align with green-fruity aromas and peppery finishes. A higher number is not automatically “better”; balance with picking time and processing is key. Phenolics also contribute to oxidative resilience.

Bridging Numbers and Nose

Marry clean figures with a fresh nose—herb, green almond, citrus peel—and a tidy finish to confirm a sound chain. Conversely, decent numbers with musty or dusty faults put sensory in the driver’s seat.

Production and Storage Tips

Clean sorting, effective washing, time–temperature control during crushing and malaxation, and well-timed filtration all improve metrics. Dark, cool tanks, inert gas and protective packaging keep that line intact in bottle.

Shopper’s Quick Read

Harvest season, lot codes and process notes on labels mirror the lab story. At home, cool–dark storage and decanting into small dark bottles turn good numbers into a good experience.

Takeaway

Peroxide, UV and phenolics are a shared language for producers and drinkers. Read with the nose, and you can trust the freshness in the glass.