The GrapeFlow blog

Winemaking & cellar, in depth

Practical, technical notes for winemakers and enologists — corrections, traceability and compliance, written by people who build cellar software.

Viticulture

Vineyard and field: ripeness, disease risk, spraying and harvest.

en·Apr 28, 2026·7 min read

Copper in organic viticulture: the limits, the maths and how to stay under them

Copper is the backbone of organic disease control and a regulated input. The EU 28 kg/ha-over-7-years limit explained, how to track metallic copper per hectare from your Bordeaux mixture, and why the field notebook is your proof.

CopperOrganic viticultureBordeaux mixtureDowny mildewComplianceVineyard
pt·28/04/2026·7 min read

Cobre na viticultura biológica: os limites, as contas e como ficar abaixo deles

O cobre é a espinha dorsal do combate a doenças em modo biológico e um fator regulado. O limite da UE de 28 kg/ha em 7 anos explicado, como controlar o cobre metálico por hectare a partir da calda bordalesa, e porque o caderno de campo é a sua prova.

CobreViticultura biológicaCalda bordalesaMíldioConformidadeVinha
en·Aug 26, 2025·8 min read

When to harvest: sugar, acidity and phenolic ripeness

Why the sugar number alone never decides the picking date, the difference between technological, phenolic and aromatic ripeness, how to sample a block properly, and how to read the ripening curve instead of a single day.

HarvestMaturityPhenolic ripenessSamplingViticultureVineyard
pt·26/08/2025·8 min read

Quando vindimar: açúcar, acidez e maturação fenólica

Porque o número do açúcar sozinho nunca decide a data da vindima, a diferença entre maturação tecnológica, fenólica e aromática, como amostrar bem um talhão, e como ler a curva de maturação em vez de um único dia.

VindimaMaturaçãoMaturação fenólicaAmostragemViticulturaVinha
en·Jul 15, 2025·8 min read

Downy mildew: reading the risk and timing the spray

How Plasmopara viticola infects, the "3-10 rule" for primary infection, why incubation makes the calendar useless and the weather essential, and how a risk model turns a forecast into a spray decision.

Downy mildewPlasmopara viticolaDisease modelsViticultureSprayingVineyard
pt·15/07/2025·8 min read

Míldio: ler o risco e acertar o momento do tratamento

Como a Plasmopara viticola infeta, a "regra dos 3-10" para a infeção primária, porque a incubação torna o calendário inútil e o tempo essencial, e como um modelo de risco transforma uma previsão numa decisão de tratamento.

MíldioPlasmopara viticolaModelos de doençaViticulturaTratamentosVinha

Biodynamics

Preparations, the lunar calendar and the record trail for Demeter.

Winemaking & corrections

Must weight, chaptalization, acidity and blending — the cellar maths.

en·Feb 24, 2026·7 min read

Wine blending and the Pearson square: hit a target every time

How volume-weighted blending really works, how the Pearson square gives you the exact proportions to hit an alcohol, acidity or SO₂ target, and why every blend should be bench-trialled first. With a free calculator.

BlendingPearson squareWine blendCellarWinemaking
pt·24/02/2026·7 min read

Loteamento de vinho e o quadrado de Pearson: acertar o alvo sempre

Como funciona realmente o loteamento ponderado pelo volume, como o quadrado de Pearson dá as proporções exatas para atingir um alvo de álcool, acidez ou SO₂, e porque cada lote deve ser primeiro ensaiado à bancada. Com uma calculadora gratuita.

LoteamentoQuadrado de PearsonLoteAdegaVinificação
en·Oct 7, 2025·8 min read

Acidity adjustments that hold: tartaric acid, deacidification and pH

When to acidify and when to deacidify, why tartaric is the acid of choice, how carbonates lower TA, and why pH — not just titratable acidity — decides the wine’s balance and stability. With a free calculator.

AcidityTartaric acidDeacidificationpHTitratable acidityWinemaking
pt·7/10/2025·8 min read

Correções de acidez que se aguentam: ácido tartárico, desacidificação e pH

Quando acidificar e quando desacidificar, porque o tartárico é o ácido de eleição, como os carbonatos baixam a AT, e porque é o pH — e não só a acidez total — que decide o equilíbrio e a estabilidade. Com uma calculadora gratuita.

AcidezÁcido tartáricoDesacidificaçãopHAcidez totalVinificação
en·Sep 16, 2025·8 min read

Chaptalization and enrichment: how much sugar, how much alcohol, and the limits

How to raise potential alcohol with sugar or concentrated must — the conversion factor, the expected gain, volume effects and the appellation limits you must respect. With a free calculator.

ChaptalizationEnrichmentPotential alcoholMustWinemaking
pt·16/09/2025·8 min read

Chaptalização e enriquecimento: quanto açúcar, quanto álcool e os limites

Como subir o álcool provável com açúcar ou mosto concentrado — o fator de conversão, o ganho esperado, o efeito no volume e os limites da denominação que tem de respeitar. Com uma calculadora gratuita.

ChaptalizaçãoEnriquecimentoÁlcool provávelMostoVinificação
en·Aug 5, 2025·7 min read

Must weight explained: Brix, Baumé, Oechsle and potential alcohol

What each must-weight scale measures, how to convert between °Brix, Baumé, Oechsle and specific gravity, and how to read potential alcohol from sugar — with the conversions and a free converter.

BrixBauméOechsleMust weightPotential alcoholMaturity
pt·5/08/2025·7 min read

Peso do mosto explicado: Brix, Baumé, Oechsle e álcool provável

O que cada escala de peso do mosto mede, como converter entre °Brix, Baumé, Oechsle e densidade, e como ler o álcool provável a partir do açúcar — com as conversões e um conversor gratuito.

BrixBauméOechslePeso do mostoÁlcool provávelMaturação

Fermentation & nutrition

YAN, staged additions, malolactic fermentation and what goes wrong.

Ageing, stability & fining

SO₂, cold tartrate stabilisation and protein stability with bentonite.

en·Jan 13, 2026·7 min read

Protein stability and bentonite: stopping haze before it starts

Why white and rosé wines throw a protein haze, how the heat test tells you the risk, how to bench-trial the right bentonite dose, and the trade-offs — volume loss and aroma — worth minimising.

Protein stabilityBentoniteFiningHazeWhite wineWinemaking
pt·13/01/2026·7 min read

Estabilidade proteica e bentonite: travar a turvação antes de começar

Porque os brancos e rosés lançam turvação proteica, como o teste de calor revela o risco, como ensaiar à bancada a dose certa de bentonite, e os compromissos — perda de volume e de aroma — que vale a pena minimizar.

Estabilidade proteicaBentoniteColagemTurvaçãoVinho brancoVinificação
en·Dec 9, 2025·8 min read

Cold stabilization: keeping tartrate crystals out of the bottle

Why potassium bitartrate drops out, how cold and the contact process force it out in the cellar instead of the bottle, the alternatives (CMC, metatartaric, electrodialysis), and how to test that a wine is actually stable.

Cold stabilizationTartrate stabilityPotassium bitartrateCMCWinemaking
pt·9/12/2025·8 min read

Estabilização tártrica pelo frio: manter os cristais fora da garrafa

Porque o bitartarato de potássio precipita, como o frio e o processo de contacto o forçam a sair na adega em vez da garrafa, as alternativas (CMC, metatartárico, eletrodiálise) e como testar que um vinho está mesmo estável.

Estabilização tártricaEstabilidadeBitartarato de potássioCMCVinificação
en·Nov 18, 2025·9 min read

SO₂ management from crush to bottle: free, molecular and the math behind every addition

Free vs total SO₂, why molecular SO₂ (not free) is what protects the wine, how pH changes everything, and the addition targets from crush through ageing to bottling. With the formula and a free calculator.

SO2Sulfur dioxideMolecular SO2WinemakingWine stabilitypH
pt·18/11/2025·9 min read

Gestão do SO₂ da vindima ao engarrafamento: livre, molecular e a matemática de cada adição

SO₂ livre vs total, porque é o SO₂ molecular (e não o livre) que protege o vinho, como o pH muda tudo, e os alvos de adição da vindima ao engarrafamento. Com a fórmula e uma calculadora gratuita.

SO2Dióxido de enxofreSO2 molecularVinificaçãoEstabilidadepH

Bottling

Yield, packaging materials and planning the line.

Compliance & traceability

Field notebook, IVV, TTB and FSMA 204 — the records an audit asks for.

pt·19/05/2026·8 min read

Declarações no IVV sem sobressaltos: existências, colheita e conta-corrente

A declaração de existências, a de colheita e produção e a conta-corrente do IVV explicadas: o que cada uma pede, como se articulam, e porque uma conta-corrente bem mantida ao longo do ano torna as declarações num clique.

IVVDeclaração de existênciasConta-correnteVinhoConformidade
pt·7/04/2026·8 min read

Caderno de campo eletrónico: o que registar, quando e como não falhar uma inspeção

O caderno de campo é obrigatório para quem aplica produtos fitofarmacêuticos. Que registos exige, os prazos, os erros que dão não-conformidade numa inspeção, e como manter tudo por talhão e pronto a exportar.

Caderno de campoDGADRFitofarmacêuticosConformidadeVinhaInspeção
en·Feb 10, 2026·7 min read

FSMA 204 and wineries: what the food traceability rule actually means for you

Most wine is not on the FDA Food Traceability List — so what, if anything, does FSMA 204 require of a winery? A clear-eyed look at where it applies, and why one-up/one-down recordkeeping is worth adopting either way.

FSMA 204FDAFood traceabilityRecallUS complianceTraceability
en·Jan 27, 2026·9 min read

TTB Form 5120.17 without the spreadsheet: a small winery’s guide

What the Report of Wine Premises Operations asks for, when you file monthly vs quarterly vs annually, the line-item logic of production, additions and removals, and how to make the filing a click instead of a scramble.

TTBForm 5120.17Wine premises operationsUS complianceWinery reporting

Sales & winery business

Distribution, CRM, trade shows and when the spreadsheet stops working.

en·Jul 18, 2026·7 min read

Free winery CRM template for Excel and Google Sheets — accounts, pipeline and follow-ups

A free, no-email-required CRM template built for winery sales: track distributor, retailer and restaurant accounts, log every conversation, run a simple pipeline with weighted values, and get an automatic dashboard of overdue follow-ups. Works in Excel and Google Sheets, with a walkthrough of how to actually use it.

Winery CRMFree templateExcelGoogle SheetsWine salesPipelineDistributorsSmall wineries
en·Jul 18, 2026·12 min read

How small wineries find (and keep) a wine distributor: three-tier, self-distribution and the questions to ask before signing

A practical playbook for boutique and family-owned wineries entering US distribution: how the three-tier system actually works, when self-distribution is the better first move, how distributors evaluate a small brand, where to find candidate wholesalers state by state, and the contract questions — franchise-state law above all — to ask before you sign.

DistributionThree-tier systemSelf-distributionWine salesSmall wineriesUS marketWholesalers
en·Jul 18, 2026·9 min read

Why spreadsheets stop working for a growing winery — and how to tell when you have crossed the line

Every winery starts on Excel, and for a while it is genuinely the right tool. Then harvest doubles, a second person needs to edit the workbook, TTB reporting means a weekend of reconstruction, and a mock recall takes four hours instead of four minutes. The failure points of spreadsheet-run wineries, the tipping points that signal it is time to move, and what to look for in replacement software.

Winery management softwareExcelSpreadsheetsSmall wineriesTTB reportingTraceabilityOperations
en·Jul 18, 2026·8 min read

Wine trade shows: measuring ROI and following up leads so the booth pays for itself

A booth at a major wine trade show costs a small winery $5,000–15,000 once travel, samples and staff time are counted — and most of that investment is decided after the show, in the follow-up. How to set an objective before you book, capture leads that survive the flight home, run the 48-hour follow-up, and calculate honestly whether the show was worth repeating.

Trade showsWine salesROILead follow-upUnified Wine & Grape SymposiumVinexpo AmericaMarketing