Fresh Guard

GROUP NO. 1  |  MINI PROJECT  |  2025

FRESHGUARD 3D

Smart Food Freshness Monitoring using MQ-135 Gas Sensor & Arduino UNO — real-time gas detection, three-stage LED alerting, zero food waste.

3+
GAS TYPES
3
LED ALERTS
4
MEMBERS
1
GROUP
🔬
MQ-135
⚡
ARDUINO
📡
SIGNAL
🔔
BUZZER
💡
LED
🍱
FOOD
ABOUT THE PROJECT

FreshGuard detects gases released from spoiling food — Ammonia (NH₃), Methane (CH₄), and Hydrogen Sulphide (H₂S) — using a precision MQ-135 sensor. Arduino UNO processes the analog signal in real time, triggering a three-stage LED and buzzer alert before contamination spreads.

NH₃ — Ammonia42%
CH₄ — Methane28%
H₂S — Hydrogen Sulphide15%
REAL-TIME ALERT PANEL
FRESHGUARD LED STATUS INDICATOR
🔴 SPOILED — DANGER
Gas level critical. Discard food immediately. Buzzer active.
🟡 WARNING — MONITOR
Gas rising. Consume soon or refrigerate immediately.
🟢 FRESH — SAFE
Gas within safe range. Food is fresh & safe to eat.
CURRENT PPM: —  |  STATUS: SCANNING…
● SYSTEM SCANNING
FRESH — SAFE
Gas concentration normal. LED glows steady green. Food is safe for consumption.
PPM < 200
WARNING — MONITOR
Moderate gas detected. Yellow LED active. Consume or refrigerate quickly.
PPM 200 – 500
SPOILED — DANGER!
Critical gas level. Red LED blinks rapidly. Buzzer triggers. Discard food now.
PPM > 500
SYSTEM WORKFLOW
🍱
FOOD
Source
💨
GAS RELEASE
NH₃ CH₄ H₂S
🔬
MQ-135
Detection
⚡
ARDUINO UNO
Processing
🔔
LED + BUZZER
Alert Output
SYSTEM COMPONENTS
🔬
MQ-135 Sensor
Gas Detection
⚡
Arduino UNO
Microcontroller
🟢
Green LED
Fresh Signal
🟡
Yellow LED
Warning Signal
🔴
Red LED
Danger Signal
🔔
Buzzer
Audio Alert
ADVANTAGES
💰
Low Cost
Affordable components
⚙️
Easy to Use
Plug & detect
⚡
Fast Detection
Real-time response
♻️
Reduces Waste
Smarter consumption
APPLICATIONS
🏠
Home
Refrigerators
🍽️
Restaurants
Kitchen safety
🏪
Supermarkets
Shelf monitoring
🏭
Food Storage
Warehouses
TEAM MEMBERS

GROUP NO. 1  ·  CMA 2025 CS BATCH

01
A
Adhira Rajesh
Panicker
CMA25CS008
Team Member
02
A
Anjana S
CMA25CS023
Team Member
03
A
Ardra A
CMA25CS028
Team Member
04
H
Harsha
Vardhini
CMA25CS051
Team Member
Smart Food  ·  Safer Life
FRESHGUARD PROJECT PROTOTYPE
FreshGuard 3D
MQ-135·ARDUINO UNO·GAS SENSOR
SYSTEM ACTIVE
FOOD QUALITY: FRESH
Gas Level (ppm)
12 ppm
Threshold
300 ppm
LED Status
● GREEN
Buzzer
SILENT
🍎 FOOD
⚙ MQ-135 SENSOR
🔷 ARDUINO
💡 LED
🔔 BUZZER

Smarter Food. Safer Life.

FreshGuard is a step towards a smarter future where technology ensures everyday safety. By detecting food spoilage early, it protects health and reduces waste efficiently.