# Aromatic Profile and Phenolic Composition of White Wines from Hybrid Grapes Grown onto Different Rootstocks and Regions of Brazil

## TL;DR

This study shows that the chemical and sensory qualities of white wines from Brazil are mainly shaped by grape variety, with lesser influence from growing conditions or rootstocks.

## Contribution

The study reveals the genetic dominance over environmental and rootstock effects on white wine composition in Brazilian regions.

## Key findings

- Moscato Embrapa and Moscatel de Jundiaí had the highest phenolic content in white wines.
- Esters like ethyl octanoate and ethyl decanoate were the main contributors to fruity and floral aromas.
- Genetic factors had a stronger influence on wine composition than environmental or rootstock variables.

## Abstract

This study investigated the phenolic and aromatic composition
of
wines produced from four white grape cultivars grafted onto two rootstocks
grown in two distinct regions of São Paulo, Brazil: Votuporanga
and Jundiaí. Wines made from Moscato Embrapa (ME) and Moscatel
de Jundiaí (MJ) cultivars exhibited the highest total phenolic
contents, averaging 278.91 and 238.94 mg/L, respectively. Environmental
factors influenced phenolic accumulation, with higher concentrations
generally observed in wines from Votuporanga. In contrast, IAC Madalena
and IAC Ribas cultivars showed greater stability across sites and
rootstocks, with minimal variation in phenolic content. Aromatic composition
analysis revealed esters as the dominant volatile class, particularly
ethyl octanoate, ethyl decanoate, and ethyl hexanoate, which contribute
to the wine’s fruity and floral characteristics. Some volatiles,
such as terpinolene and isoamyl acetate, showed cultivar-specific
occurrence, affecting sensory characteristics. Principal component
analysis (PCA) of volatile organic compounds demonstrated that genetic
factors had a stronger influence than environmental or rootstock variables,
with apparent clustering by cultivar. High-performance liquid chromatography
with diode array detection (HPLC-DAD) identified phenolic acids as
the most abundant compounds, with Moscato Embrapa wines showing the
highest concentrations, especially caftaric acid. cis-resveratrol, a bioactive stilbene, was notably present only in IAC
Ribas and IAC Madalena wines. PCA of phenolic compounds further supported
the predominance of genetic influence on wine composition, with limited
impact from location or rootstock. Overall, the results emphasize
that the phenolic and aromatic profiles of wines produced from white
grapes are primarily determined by the genetic makeup of the cultivars,
with environmental conditions and rootstock playing secondary roles.
These findings have implications for grape selection and vineyard
management aimed at producing wines with desired chemical and sensory
characteristics.