The Complete Guide to Dry Matter in Fresh Produce

When selling produce, it's crucial to ensure you provide customers with the highest quality fruits and vegetables. You can sometimes assess quality simply by examining the product, but in most cases, you'll want something a little more foolproof.

Measuring produce dry matter is an effective way to determine quality, maturity and optimal harvesting time, thus reducing spoilage and allowing you to provide better products. How exactly do you go about doing this? This dry matter guide explores some different ways to measure fruit dry matter testing and conduct dry matter analysis in fresh produce.

What Is Dry Matter?

Dry matter in produce refers to the material that remains after water loss in a fruit, stem, leaf or roots. Conversely, the moisture content reflects the amount of water present in the produce being tested.

Produce dry matter results from the accumulation of:

• Starches
• Carbohydrates
• Oils
• Sugars
• Antioxidants
• Proteins
• Vitamins
• Minerals
• Fiber
• Lipids
• Volatile compounds

The Importance of Measuring Dry Matter Content

Dry matter essentially measures produce dry matter quality and fruit maturity testing. Dry matter changes throughout the stages of fruit development, which can indicate maturity in climacteric fruits that store sugars as oil content or starch — like mangos, pears, apples and bananas — and non-climacteric fruits that store sugars in their soluble forms — like melons, peaches, grapes and citrus fruits. Aside from genotype, produce dry matter accumulated in produce also depends on field conditions where plants are grown and the cultivation methods used.

How Dry Matter Varies in Fruits and Vegetables

Now, let's explore some examples of how fruit dry matter testing and dry matter analysis can vary by produce type:

• Avocado: Unlike other produce types, dry matter doesn't necessarily indicate maturity in avocados. Its oil content correlates with the maturing process, increasing as the avocado matures. Avocados are usually declared mature at 11.2% oil content based on dry matter analysis.
• Bell pepper: Typically, bell peppers are at their best quality when harvested at maximum produce dry matter content. During this stage, there's less ascorbic acid that hardens the vegetable. Ascorbic acid continues decreasing post-harvest. Bell peppers harvested at maximum dry matter content — 7.35% — tend to have the longest storage time.
• Cabbage: The first dry matter peak of 8.6% is usually the best time to harvest cabbage. If harvested later, they can lose weight from water decrease through cracking of leaves and perspiration, as determined through fruit maturity testing.
• Tomato: Produce dry matter content increases in tomatoes as they ripen, primarily due to water loss through transpiration. The highest dry matter content is usually found in fully ripe tomatoes. The maximum dry content at which the tomato should be harvested mainly depends on the variety, but it can vary from 5%-8% of fresh fruit weight, making fruit maturity testing essential.

How to Measure Dry Matter Content

There are multiple ways of measuring produce dry matter to determine if the produce has reached ample maturity for harvesting. This dry matter guide covers the two main techniques: conventional, manual methods and modern technology-based methods for fruit dry matter testing and dry matter analysis.

1. Conventional Methods

With conventional methods of measuring produce dry matter, a sample of fresh produce is taken. The sample is weighed to determine the "wet weight" or moisture content. The produce is then dried in a dehydrator, oven or microwave until the moisture has fully evaporated.

Next, the sample is weighed again to measure the dry weight. The following equation is then used to calculate the dry matter analysis:

• (Dry weight / wet weight) x 100 = percentage of dry matter

Dry matter measures the ratio of fresh weight — the weight of the fruit before the drying process takes place — to dry weight. As you can likely imagine, the main drawback to this method is that it's highly labor-intensive and time-consuming. Additionally, it destroys the produce in the process.

2. New Methods

Alternatively, new handheld sensory instruments simplify this process, using near-infrared (NIR) spectroscopy to detect produce dry matter. These non-destructive tools can accurately estimate dry matter levels without affecting the fruit or vegetable being tested, making fruit dry matter testing and dry matter analysis faster and more practical.

Results and measurements can be acquired instantly in packing warehouses, orchards and fields. Furthermore, the devices allow you to conveniently organize thousands of readings. Let's look at some of these devices below.

F-751 Mango Quality Meter

Using state-of-the-art NIR technology, the F-751 Mango Quality Meter by Felix Instruments non-destructively and precisely measures produce dry matter and total soluble solids (TSS) or Brix, the key ripeness and quality indicators in mangos. This device allows growers to predict crop harvest dates through fruit maturity testing, thus reducing guesswork and minimizing spoilage.

You can seamlessly transfer the data obtained from the F-751 Mango Quality Meter to a computer or upload this data to the Fruitmaps® cloud. This crop mapping software enables mango growers to predict harvest timing more accurately than ever and monitor their farms in real time from any location.

F-751 Avocado Quality Meter

When packers and growers rely solely on food dehydrators or microwave ovens to assess produce dry matter in avocados, the process is incredibly labor-intensive and time-consuming. Additionally, when repeating this fruit dry matter testing process throughout the growing season, large quantities of valuable avocados are destroyed over time.

The F-751 Avocado Quality Meter from Felix Instruments completely transforms this process. Using non-destructive NIR light, the machine can accurately measure avocado produce dry matter in seconds, saving time without wasting quality fruit through rapid dry matter analysis.

Considering the increasing popularity and price of avocados, an NIR-based quality meter can be an asset for packers, farmers and suppliers alike seeking accurate fruit maturity testing solutions.

F-750 Produce Quality Meter

The F-750 Produce Quality Meter by Felix Instruments can be used for various produce species.

It uses NIR spectroscopy to estimate produce dry matter, color, titratable acidity and TSS. Its precise readings can also be used for scientific studies on fruit maturity testing and quality through comprehensive dry matter analysis.

Operating like a high-powered flashlight, the machine releases light particles into a produce sample, measuring the NIR light interference with molecular components inside the sample. From providing an objective analysis for produce dry matter content to determining optimal harvest times, the F-750 has various applications for fruit dry matter testing.

For many years, the F-750 has been used for non-destructive and rapid measurements of dry matter, soluble solids concentration (SSC) and external and internal color within seconds, optimizing earnings and reducing food loss through advanced dry matter analysis.

This compact, versatile device makes it easy for retailers, suppliers and farmers to operate inside a lab or out in the orchard. Its convenient, intuitive user interface and customizable model-building software allow for seamless use in conducting fruit maturity testing.

Browse Dry Matter Measuring Devices at QA Supplies

Having the right equipment is essential when measuring produce dry matter in vegetables and fruits. This dry matter guide demonstrates why advanced testing methods are crucial for quality control. At QA Supplies, our fruit dry matter testing devices and dry matter analysis tools use advanced technology to improve outcomes at your facility or farm, helping you sell better products to your customers. Browse our selection of dry matter meters today!