Lutron Fruit Hardness Tester - FR-5105

The Lutron Fruit Hardness Tester FR-5105 is a professional digital penetrometer engineered to measure the firmness and maturity of fruits with laboratory-grade precision. This handheld fruit hardness meter delivers objective, quantifiable data on fruit texture replacing subjective squeeze tests and inconsistent manual methods that compromise quality control decisions.

Designed for agricultural professionals, food scientists, and quality assurance teams, the Lutron FR-5105 measures fruit firmness up to 20.00 Kg (44.10 LB / 196.10 Newton) with 0.01 Kg resolution and +/-(0.5% + 2 digits) accuracy. Four interchangeable penetrometer tips accommodate everything from delicate strawberries to hard apples, making this digital fruit tester indispensable for fruit farms, research institutions, processing facilities, and export quality inspection stations.

Professional Fruit Firmness Measurement

Triple-Unit Display with High Resolution

The Lutron FR-5105 simultaneously displays measurements in three units -- Kilogram (Kg), Pound (LB), and Newton (N) -- eliminating manual conversion errors. With 0.01 Kg / 0.01 LB / 0.05 Newton resolution, the meter captures subtle firmness variations that indicate ripeness stages, storage degradation, and variety-specific characteristics. The minimum display of 0.02 Kg / 0.07 LB / 0.3 Newton ensures reliable detection of even minor texture changes.

+/-0.5% Accuracy for Consistent Quality Control

Achieve dependable measurement repeatability with +/-(0.5% + 2 digits) accuracy within the calibrated temperature range of 23C +/- 5C. This precision level satisfies HACCP requirements, export certification standards, and research publication needs. The exclusive microprocessor LSI circuit eliminates drift and maintains calibration stability across extended testing sessions.

Fast and Slow Measurement Modes

Select between two LCD update speeds based on your application requirements. Fast mode updates approximately every 0.2 seconds for rapid sorting and high-volume inspection lines. Slow mode updates approximately every 0.6 seconds for stable readings on delicate fruits or research-grade documentation where maximum precision takes priority over speed.

Full Scale Tare and Zero Functions

The zero/tare control accommodates up to full capacity, enabling net firmness measurement by subtracting container or fixture weight. This function simplifies batch testing protocols and ensures that only fruit resistance contributes to the final reading -- critical for standardized quality assessment procedures.

Key Features of the Lutron FR-5105

Four Interchangeable Penetrometer Tips

Tip Size	Fruit Type	Application
11 mm (FRTP-11)	Large hard fruits	Apples, pears, melons, hard citrus
8 mm (FRTP-8)	Medium firm fruits	Peaches, plums, medium apples
6 mm (FRTP-6)	Small soft fruits	Grapes, kiwis, apricots
3 mm (FRTP-3)	Delicate berries	Strawberries, blueberries, cherries

Each tip threads securely onto the measurement head and maintains consistent penetration geometry for reproducible results. The hardened steel construction resists deformation through thousands of tests, ensuring long-term measurement integrity.

RS-232 Data Output Interface

Connect the Lutron FR-5105 directly to computers, data loggers, or laboratory information management systems via the built-in RS-232 serial port. Export measurement data for statistical analysis, trend reporting, and regulatory documentation without manual transcription errors. This digital connectivity transforms the hardness tester from a standalone device into an integrated quality control system component.

Large LCD Display with Peak Hold

The high-contrast LCD screen presents firmness values clearly in all lighting conditions. Peak hold function captures and displays the maximum resistance reading during penetration the standard metric for fruit firmness assessment. The display reverse feature ensures readability when the unit is mounted on a stand or positioned at awkward angles during testing.

Dual Power Options

Operate the Lutron FR-5105 using 6 x 1.5V AA batteries for portable field testing, or connect the DC 9V adapter for continuous laboratory operation. The approximate 28 mA power consumption delivers extended battery life for all-day harvesting assessments, while the adapter eliminates battery replacement during stationary testing protocols.

Stand Mounting Capability

Mounting holes on the instrument back case enable secure stand attachment for hands-free operation. This configuration is ideal for repetitive testing stations where operators need both hands free for fruit positioning and data recording. The stable mounting reduces measurement variability caused by hand-held positioning inconsistencies.

Robust Operating Environment

The Lutron FR-5105 operates reliably from 0C to 50C (32F to 122F) at humidity levels below 80% RH. This wide environmental tolerance supports field testing in orchards, greenhouse research, cold storage facilities, and climate-controlled laboratories without performance degradation.

Applications of the Lutron FR-5105 Fruit Hardness Tester

Fruit Farm Harvest Timing

Determine optimal harvest windows by tracking firmness decline as fruits mature. The Lutron FR-5105 provides objective data that complements color and sugar content measurements, enabling precision agriculture decisions that maximize yield quality and storage potential. Test multiple orchard blocks to identify maturity variations across different soil, elevation, and irrigation zones.

Agricultural Research and Development

Support breeding programs, cultivation technique studies, and post-harvest physiology research with quantifiable firmness data. Universities and agricultural colleges use the Lutron FR-5105 to publish peer-reviewed findings on variety performance, storage treatment effectiveness, and ripening agent impacts on fruit texture.

Fruit Processing and Packaging Quality Control

Incoming inspection teams verify that supplier fruits meet firmness specifications before accepting batches for processing. Outgoing inspection confirms that packaged products maintain adequate firmness for shelf life requirements and transport durability. The RS-232 output integrates directly with factory quality management databases for automated compliance tracking.

Export Certification and Customs Inspection

Meet international phytosanitary standards and buyer specifications with documented firmness certificates. Many export markets require objective maturity evidence beyond visual inspection. The Lutron FR-5105 generates the traceable, calibrated data that customs agents and import inspectors accept as proof of product quality.

Cold Storage and Supply Chain Monitoring

Track firmness loss during refrigerated storage to optimize inventory rotation and predict remaining shelf life. Compare pre-storage and post-storage readings to identify temperature abuse events or ethylene exposure that accelerates softening. This data-driven approach reduces waste and improves logistics planning.

Supermarket and Retail Quality Assurance

Receiving departments verify that delivered fruits meet advertised quality grades. The compact size allows testing directly at loading docks without laboratory setup. Reject substandard batches before they reach produce displays, protecting brand reputation and customer satisfaction.

Why Choose the Lutron FR-5105

Brand Reliability and Calibration Certificate

Lutron is a recognized manufacturer of precision measurement instruments. Each FR-5105 ships with a factory calibration certificate traceable to international standards, providing the documentation required for ISO-certified operations, research publications, and regulatory submissions.

Versatile Tip System

Four tip sizes in one kit eliminate the need for multiple hardness testers. Switch tips in seconds without tools -- from 11 mm for warehouse apples to 3 mm for export strawberries. This versatility reduces capital expenditure while standardizing measurement protocols across diverse product lines.

Digital Precision Over Analog Methods

Replace spring-based penetrometers that suffer from hysteresis, wear, and parallax reading errors. The Lutron FR-5105's microprocessor-controlled load cell delivers consistent, drift-free measurement with digital clarity. The RS-232 output eliminates handwritten data sheets and transcription mistakes.

Cost-Effective Professional Tool

Access laboratory-grade fruit texture analysis at a fraction of the cost of universal testing machines or texture analyzers. The durable construction and standard AA battery power minimize ongoing operating expenses, while the comprehensive tip set covers most commercial fruit varieties without accessory purchases.

Specification	Details
Measuring Range	20.00 Kg / 44.10 LB / 196.10 Newton
Resolution	0.01 Kg / 0.01 LB / 0.05 Newton
Min. Display	0.02 Kg / 0.07 LB / 0.3 Newton
Accuracy	±(0.5% + 2 digits), within 23°C ± 5°C
LCD Update Time	Fast: ~0.2 sec; Slow: ~0.6 sec
Data Output	RS-232 serial computer interface
Capacity	Max. 30 kg
Full Scale Detection	Approx. 0.4 mm max
Zero/Tare Control	Max. full capacity
Circuit	Exclusive microprocessor LSI-circuit
Power Supply	6 × 1.5V AA batteries or DC 9V adapter
Power Consumption	Approx. DC 28 mA
Operating Temperature	0°C to 50°C (32°F to 122°F)
Operating Humidity	Less than 80% RH
Mounting Holes	Provided on back case for stand mounting

What is Included

Qty	Included Item
1	Lutron FR-5105 Fruit Hardness Tester Main Unit
1	11 mm Penetrometer Tip (FRTP-11)
1	8 mm Penetrometer Tip (FRTP-8)
1	6 mm Penetrometer Tip (FRTP-6)
1	3 mm Penetrometer Tip (FRTP-3)
1	Carrying Case
1	Instruction Manual
1	Calibration Certificate

Note: 6 × AA batteries and a DC 9V adapter are not included. Use high-quality alkaline batteries or connect the adapter for continuous operation.

Frequently Asked Questions

What fruits can the Lutron FR-5105 test?

The Lutron FR-5105 tests apples, pears, grapes, strawberries, and most commercial fruits using four interchangeable penetrometer tips designed for hard, medium, small, and delicate fruits.

What is the measuring range and accuracy?

The instrument measures up to 20.00 kg (196.10 N) with a resolution of 0.01 kg and an accuracy of ±(0.5% + 2 digits) within 23°C ± 5°C.

Does it include calibration certification?

Yes, each unit ships with a factory calibration certificate traceable to international standards.

Can data be exported to a computer?

Yes, the built-in RS-232 serial interface connects to computers and data loggers for automated recording and analysis.

What power options are available?

The Lutron FR-5105 operates on six AA batteries for portable use or a DC 9V adapter for continuous laboratory operation.

Is it suitable for agricultural research?

Yes, it is widely used by fruit farms, agricultural colleges, research departments, and fruit processing companies for quality control and fruit maturity studies.