2026 Grape Harvest: Managing Laboratory Analyses at the Winery During Peak Work Periods

During a compressed harvest, it’s not just the speed of the analyses that changes—their order changes as well

The 2026 harvest is presenting many wineries with a problem that goes beyond just the heat or the early harvest.

Above all, it’s about time.

When vineyard blocks and grape varieties that normally ripen in succession reach harvest conditions within a narrower window, the pressure quickly shifts from the vineyard to the winery: there is a simultaneous increase in grape deliveries, processing line utilization, demand for refrigeration, the need for available tanks, and, above all, the number of decisions that must be made in just a few hours. This is known as “harvest compression.”

In 2026, this phenomenon was reported in several international wine-growing regions. Vinetur described the loss of operational time as one of the most significant aspects of the season: not only do grapes ripen earlier, but more vineyards simultaneously reach critical ripeness thresholds, putting pressure on staff, presses, tanks, refrigeration, and transportation.

The Italian calendar also offers significant examples. In Franciacorta, the harvest began on July 30, 2026—the first time it has started in July. The Consortium attributed this early start to high temperatures and limited water availability, which accelerated the growing cycle and ripening.

But simply knowing that the harvest is early isn’t enough. For those working in the winery, the question is more practical: when multiple batches arrive at the same time, which analyses should be performed first?

During the grape harvest, we’re used to thinking in terms of parameters: sugar, acidity, pH, malic acid, available nitrogen, and polyphenols.

But when time is limited, not all data is equally urgent. One parameter may be important for the wine’s final quality without being the one needed in the first few minutes after delivery; another, on the other hand, can immediately change how a batch is handled.

That’s why we suggest interpreting harvest analyses based on a hierarchy of priorities.

The principle is simple: first, measure what can influence the next decision. It is therefore not a ranking of the parameters’ absolute importance, but rather of their urgency in decision-making.

We can divide this into three levels of analysis:

1. quickly understanding what has entered the winery;
2. identifying risks before fermentation begins;
3. monitoring process decisions, particularly extraction in red wines.

Sugar content is, of course, a key factor, but in a hot growing season it should not be considered in isolation.

High temperatures and water stress can, in fact, accelerate sugar accumulation while simultaneously altering the balance of acids and other components in the berry. Technological, phenolic, and aromatic ripeness do not necessarily progress at the same rate.

For an initial assessment of the batch, it is therefore useful to consider three parameters together: sugars + pH + total acidity.

pH: the factor that alters the meaning of the other parameters

pH influences various aspects of winemaking and storage and is one of the first values to determine in order to understand the balance of a must. If multiple batches are arriving one after another, knowing the pH immediately allows you to identify those that deviate from the expected profile and warrant priority attention.

This figure does not automatically determine the winemaking decision, but it provides an initial objective criterion to guide it.

Total Acidity: pH Needs Context

However, pH alone does not reveal the full picture of acid balance. This is why it is also necessary to determine total acidity.

When considered together, pH and total acidity already allow us to distinguish situations that a single value might conceal.

Sugars: Essential, but Not Synonymous with Full Ripeness

Sugars remain an essential reference point for assessing fermentation potential and possible alcohol development. The critical point for a vintage like 2026 is to avoid the automatic equation: more sugar = more mature grapes overall.

Heat can accelerate some processes more than others. For this reason, sugar content becomes more meaningful when interpreted in conjunction with acidity levels and, where necessary, phenolic ripeness.

Once the batch has been classified, the question changes: How might it behave during fermentation?

At this stage, two analyses become particularly important: L-malic acid and readily assimilable nitrogen.

L-Malic Acid: Looking Beyond Total Acidity

Malic acid is particularly sensitive to high temperatures, and its degradation accelerates in the heat. It is therefore possible for two musts with relatively similar total acidity to have different acid profiles. For this reason, when the initial profile suggests it, the second level of analysis involves the specific determination of L-malic acid.

The specific measurement of malic acid thus adds more precise information about the must’s acid composition to the overall total acidity data.

YAN: Measure First, Then Determine Nutrition

A second crucial aspect concerns the availability of nitrogen for the yeasts. In fact, drought conditions severely limit transpiration and the uptake of nutrients from the soil: under water stress, the vine tends to use nitrogen almost exclusively for its own metabolism, thus producing musts deficient in Yeast Assimilable Nitrogen (YAN). Managing a product with high alcohol potential combined with nutritional deficiencies exposes one to an increased risk of fermentation stoppages, while also promoting the development of reduction-related aromatic defects, such as the production of hydrogen sulfide (H₂S).

In this scenario, automatically applying the same nutritional protocol to all batches is an oversimplification. Rather than mechanically replicating standard winery procedures, it is essential to assess the actual nitrogen content of each tank in order to tailor a targeted intervention. From this perspective, analytical data does not replace the winemaker’s experience and decisions, but rather provides the objective basis necessary to best manage the specific characteristics of each individual must.

For red grapes, after acid balance and nutritional conditions, the phenolic component comes into play.

Water stress can reduce berry size and alter the ratio of pulp to skin. Heat can also affect the accumulation of sugars, acids, and compounds responsible for color and structure in different ways.

TPI and Anthocyanins: Monitoring the Progress of Extraction

For red grapes, Total Poliphenols Index (TPI) and total anthocyanin allow us to track the evolution of phenolic compounds and color during maceration, complementing the winemaker’s tasting notes and experience with objective data.

Being able to perform these measurements directly in the winery facilitates comparisons between tanks, batches, and different stages of fermentation.

The goal is not to replace sensory evaluation or set automatic thresholds, but to understand how extraction is evolving in order to more effectively adjust pump-overs, punching down, and maceration duration.

We can therefore summarize the process into three stages of initial analysis, in addition to monitoring the progress during fermentation.

In a compressed harvest, the value of the sequence lies precisely here: prioritizing the data that can still influence how a batch is managed.

CDR WineLab® was created specifically to bring analysis to where decisions are made.

The methods developed by CDR laboratories require minimal or no sample preparation and use pre-vialed reagents to perform analyses directly in the winery. During a busy harvest, CDR WineLab® allows for the comparison of multiple lots while decisions regarding those lots are still pending. A result available after a decision has been made remains merely a piece of data.

A result available earlier can become an operational tool.

The 2026 harvest highlights that the winemaker’s experience remains irreplaceable.

But it also reminds us of something less obvious: when time is short, it becomes riskier to rely on a single parameter or to automatically apply the same approach to all batches.

Rapid analysis isn’t meant to replace experience, but to provide information while it’s still useful. That’s why asking which analyses to perform first leads to an answer that isn’t just a simple list, but a sequence that evolves alongside the decisions that need to be made.

Upon the arrival of the grapes, analyses serve to distinguish between batches and identify those requiring greater attention; during fermentation, their function changes, allowing us to verify that the process is proceeding as expected.

The logic remains the same from the arrival of the grapes to the end of fermentation: measure first the parameter that could influence the next decision.

When all the grapes arrive at the same time, this approach allows us to continue treating each lot according to its true nature.

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