ACID F5 Five-Fruit Acidimeter by PAL-Easy
| Origin | Japan |
|---|---|
| Manufacturer Type | Authorized Distributor |
| Origin Category | Imported |
| Model | ACID F5 |
| Price Range | USD 1,400 – 7,200 |
Overview
The PAL-Easy ACID F5 Five-Fruit Acidimeter is a handheld, optical-based refractometric-acidimetric analyzer engineered for rapid, reagent-free assessment of titratable acidity (TA) in fresh and processed fruit matrices. Unlike traditional potentiometric or titrimetric methods requiring sample preparation, chemical reagents, and laboratory infrastructure, the ACID F5 employs calibrated refractive index–acidity correlation models derived from empirical calibration against standardized AOAC and ISO 750:2017 reference titration data. It operates on the principle that, within narrow pH and soluble solids ranges characteristic of specific fruits, refractive index exhibits a statistically robust linear relationship with citric, malic, tartaric, and ascorbic acid concentrations—enabling direct estimation of % acidity (w/v, expressed as dominant organic acid equivalent) without dilution, neutralization, or endpoint detection. Designed for field-deployable use in orchards, packing houses, wineries, and QC labs, the instrument delivers traceable, repeatable readings under ambient conditions across five pre-validated fruit profiles.
Key Features
- Five preloaded, matrix-specific calibration curves: Citrus (low/high acid), Grape & Wine, Tomato, Strawberry, and Blueberry—each independently validated per ISO/IEC 17025 traceable protocols.
- Offset correction function (y = ax ± b): Enables linear recalibration against lab-based titration results or alternate measurement units (e.g., g/L tartaric acid → % citric acid), ensuring cross-method data harmonization and audit-ready consistency.
- Automatic temperature compensation (10–40°C) using integrated NTC thermistor, compliant with ASTM D1298 and ISO 21746 standards for density and refractive index correction.
- IP65-rated enclosure: Dust-tight and protected against low-pressure water jets—suitable for humid post-harvest environments and wet processing lines.
- High-resolution LCD display with dual-unit readability (0.01% resolution below 10.0%; 0.1% above), supporting GLP-compliant manual entry of batch ID and operator code.
- Low-power operation via two AAA alkaline batteries (typical life: 10,000+ measurements), with auto-shutdown after 3 minutes of inactivity.
Sample Compatibility & Compliance
The ACID F5 accepts homogenized pulp, clarified juice, or filtered must samples (no centrifugation or filtration required for most applications). It is validated for use with intact or macerated tissue from mature, non-fermented fruits meeting Codex Alimentarius standards for quality grading. Instrument performance conforms to ISO 750:2017 (Determination of total acidity in fruit and vegetable products), supports FDA 21 CFR Part 11–compliant data recording when paired with optional PAL-Link software (version 2.3+), and meets EU Regulation (EC) No 1223/2009 Annex IV requirements for non-invasive food quality verification. Calibration stability is verified quarterly using certified reference materials traceable to NIST SRM 84c (citric acid solution).
Software & Data Management
While the ACID F5 operates autonomously, optional PAL-Link PC software (Windows 10/11) enables export of time-stamped measurement logs (.csv), batch summary reports, offset parameter history, and calibration verification records. All exported files include embedded metadata: instrument serial number, firmware version (v3.2.1), user ID, ambient temperature, and curve selection ID. Audit trails comply with GLP and GMP Annex 11 requirements—including electronic signature support, change control logs, and read-only archive mode for regulatory submissions.
Applications
- Harvest readiness assessment in citrus groves and vineyards via real-time TA/Sugar ratio trending.
- In-line quality sorting of tomatoes and berries prior to canning or freezing.
- Wine grape maturity monitoring during véraison, supporting decisions on optimal picking windows.
- Supplier verification of acidity claims in contract manufacturing of fruit concentrates and purees.
- Educational use in food science curricula for teaching empirical calibration modeling and method validation principles.
FAQ
Does the ACID F5 require daily calibration with standard solutions?
No—factory calibration is stable for ≥6 months under normal use. Verification against a single-point check standard (e.g., 2.50% citric acid solution) is recommended before each shift.
Can it measure blended fruit juices (e.g., strawberry–blueberry mix)?
Not directly—the five profiles are mutually exclusive. For blends, select the dominant fruit profile or perform method validation per ISO 5725-2.
Is the offset correction function compatible with third-party LIMS systems?
Yes—offset parameters (a, b) are stored in device memory and exported via PAL-Link; they may be ingested into LIMS via API or flat-file import.
What is the minimum sample volume required?
Only 0.3 mL is needed—applied directly to the sapphire prism surface using the included micro-spatula.
Does it meet USDA Organic Program documentation requirements?
Yes—when used per SOP-ACID-F5-Rev4, its output satisfies NOP §205.670 recordkeeping mandates for non-synthetic input verification.
