International Produce Training

You most likely have been receiving grapes, apples, pears, plums and peaches from Chile.  Much of the fruit is shipped immediately to distribution centers while some of the fruit is placed in cold storage.  One defect you may see, especially from plums that may have been in cold storage is shriveling.

The shriveling will most likely be caused by the fruit losing some its moisture, yet it will still be firm to the touch.  When inspecting plums do not squeeze the fruit to make the skin shrivel; for the plum to be considered a defect by shriveling it must be noticeable upon careful examination. 

How much is allowed, on the plum, to be considered shriveled?  Any amount.  If you can see the shriveling, the plum is a defect. 

How many plums can have shriveling?  Because shriveling is always considered a serious damage defect, only 6% of the plums in a lot are allowed to have shriveling.

The shriveling is usually found around the stem area, but in extreme cases the shriveling may extend down the sides, especially along the suture.

Of course nothing is ever simple.  If you are inspecting President Plums, shriveling is much more common. For this reason the USDA allows an area of up to a 1/2 inch of shriveling extending from the stem scar.  In other words, if the shriveling on President Plums extends greater than 1/2 inch from the stem scar it is a defect, considered as serious damage.

Within the next week you may begin seeing some problems with some Florida tomatoes, if you happen to see any Florida tomatoes at all.  The recent nights of below freezing temperatures produced some major issues for the Florida tomato growers.  The complete picture of damage will not be known for a few more weeks.

Alternaria Rot is a fungus disease to tomatoes that may occur wherever tomatoes are grown.  The fungus causing this decay is a weak pathogen that is usually unable to cause an active rot on sound, uninjured, green tomatoes.  Unfortunately tomatoes that have been subjected to cold temperatures too long are extremely vulnerable to Alternaria rot.

Typical symptoms on chill-injured fruit are a ring of decay around the stem scars and numerous lesions at skin breaks over the surface of the fruits.  The lesions are shallow, sunken, and grayish black and will become darker in color turning black.

Alternaria does not produce a watery-leaking decay, as the infected tomatoes usually remain firm.  When the fungus produces some black mold spores the chance of spreading the decay to adjacent sound tomatoes is increased.

The USDA Grade Standard allows for 5% of the tomatoes being soft or decayed.

Probably one of the easiest commodities to learn how to inspect is Strawberries.  Although there are a few defects that are commonly found, most are easy to identify.  Except one.  By far the most common defect found while inspecting strawberries is bruising; and it is easily the most misidentified. Way too many inspectors, whether they are USDA inspectors or company’s own quality assurance inspectors, confuse bruised strawberries with decayed strawberries.  They almost always error on identifying it as decay, when it is really bruising.

Take a look at the image above.  The area on this strawberry is definitely indented or sunken, no evidence of mold, nor does it appear to be soft or mushy.  This is a bruise.  No doubt about it.  The only question; is the bruised area large enough to be considered a defect?  The USDA inspection instructions state the bruise must exceed 1/2 inch in area on a strawberry 1-1/2 inches in diameter.  If you score the strawberry as a defect, it counts against the 10% tolerance for total defects.

But now the confusion begins.  While inspecting you come across this strawberry, as shown above.  You can definitely see the sunken area, still no evidence of mold, and it appears to be soft and mushy.  The USDA inspection instructions tell us to score any soft or mushy areas as serious damage by bruising (no matter what size of area is affected).  But is it decay?  Many inspectors will quickly call this type of defect decay, simply because it is soft and mushy and may be leaking strawberry juice all over your hands.  They may be incorrect.  To be certain you must touch the soft area with your finger and determine if the soft or decayed tissue scoops out.  If so, then it is decay.  Also if you take some of the soft or decayed tissue and rub it between your fingers, if it is decay the tissue will disintegrate.

Is it confusing, especially to a new inspector?  Absolutely.  Blue Mold Rot is a very common decay found in strawberries but in early stages you will not see any mold growth.  Typical of Blue Mold Rot the decayed tissue will scoop out, leaving a cavity on the side of the strawberry.

My advice, take your time when inspecting strawberries, and don’t be too quick to jump on calling bruised berries decayed berries.

One of the most unique defects is contact spot.  Simply put, if a perfectly good lemon has mold or decayed tissue on it’s skin, the lemon is scored as a defect.  The USDA inspection instructions state: “Any size area on a lemon that shows evidence of having been in contact with decay or mold is scorable as contact spot.  Any amount is scorable as serious damage in all grades.  If the affected tissues exhibit decay characteristics (e.g., disintegration,  mushiness, mold growth, etc,),  score the fruit as decay”

Unfortunately, one of the most common decays of lemons is Blue Mold Rot and Green Mold Rot.  The decayed lemons will be covered with mold spores and the adjoining lemons may have mold on their skin, from touching the decayed lemon.  The problem gets much worse if 2 or more lemons in the carton are affected by the decay.  As you can see from the above picture, the perfectly sound lemon on the left would be scored as a serious damage defect. 

How much mold is allowed on a lemon?  Zero…..the mold or slimy decayed tissue on a good lemon is a free from defect, meaning if you can see it, it is a defect.

What about other citrus?

No, contact spot is not a defect in other citrus, or any other commodity.  That is what makes this defect so unique; it is only a defect for lemons.  So remember, when you pop that lid on a carton of lemons and the mold spores fly out, get ready to start looking for the lemons with contact spot as well as the decaying culprits.

Many of you have probably cut into an apple and sometimes noticed a watersoaked, glassy appearance.  This defect is called watercore.  Visible watercore if you can detect the glassy appearance without cutting the apple, or invisible watercore when there is not indication of the defect, unless you cut the apple in half.

This defect is found in practically all apple growing regions around the world.  It is usually attributed to growing conditions with intense heat and sunlight.  High temperatures at the time the apples are approaching maturity favor its development.  The disease is most likely to occur in fruits that are freely exposed to the sun.   Certain varieties are more susceptible to watercore,  such as Rambo, Jonathan,  Red Delicious, Stayman and Winesap.

But is it a defect? 

• According the U.S. Grade Standards for Apples; If you find invisible watercore in Fuji apples it is never scored as a defect.  Never.

• If you discover invisible watercore prior to February 1st, in any variety of apples, it is never scored as a defect.

• Visible watercore is a free from defect of all varieties of apples, includng Fujis (any time of year) in U.S. Extra Fancy, U.S. Fancy and U.S. No. 1 grades and any amount of watercore that is visible externally shall be scored against the 10% tolerance for the grade.  If the area of visible watercore exceeds 1/2 inch, the apple is scored as serious damage, against the 5% tolerance.

OK, it is after February 1st, and I am finding invisible watercore.  How much is allowed?

• Invisible watercore that is severe shall be scored as damage (10% tolerance) against the U.S. Extra Fancy and U. S. Fancy after January 31st of the year following the year of production (except for the Fuji variety of apples).  It is never a defect of U.S. No. 1 or Cat. 1 apples.

• The apple may be scored; as a defect by one of three ways; 

  1) If watercore extends from a vascular bundle to the core or,
  2) when the affected areas surrounding three or more vascular bundles meet or coalesce or, 
  3) more than a slight degree outside the circular area formed by the vascular bundles.

The above photo is an official visual aid depicting 4 separate apples, cut in half, with scoreable invisible watercore.  The top two apples and the apple on the bottom left show the watercore extending from the core to the vascular bundles.  The apple on the bottom right depicts the watercore coalescing with three or more vascular bundles.

If you would like further information regarding watercore please click this link, from Washington State University.

When inspecting pears, especially the summer and fall varieties, such as Bartletts, you may come across different types of scarring, ranging in color and in size.  The affected areas may be smooth, or they may be slightly rough to rough, to the touch.  The discoloration may range from a light brown color to a dark black.

The image above is depicting a pear with typical scarring.  This type of discoloration will not get worse, meaning the area of discoloration will not increase in size, and the color will not change.  This scar is considered a quality defect.

There is a type of scarring you need to be more concerned with.   The summer and fall varieties of pears are very susceptible to discoloration affecting the skin of the pear.  During the packing process the pears are handled with care, trying to avoid having the pears rub against each other while packing or on the grading line.

The discoloration may range in color from a light brown to black.  The discoloration will appear wherever the pear may have been in contact with other pears, rolling along a grading line, or movement within the carton during the shipping process.  Determining the exact cause of this defect is difficult.  This discoloration is called “dark skin discoloration” by the USDA Inspection Service.  It is a condition defect, meaning the area affected may increase in size and the discoloration may become darker in color.

When scoring dark skin discoloration;

•  if the discoloration is medium brown in color, score as damage when the affected area exceeds 5% of the surface 
• if the discoloration is dark brown to black in color, score as damage when the affected area exceeds 3/4 inch in diameter.

The defect is scored as damage or as serious damage, against the 10% and 5% tolerances for each.

As I roamed the produce aisles of our local grocery store yesterday I saw displays of new crop apples.  You may still be receiving some varieties of last year’s crop, as the growers begin to clean out their controlled atmosphere storage rooms.  With the storage apples you may encounter a few apples with moldy stems, and wonder if this is a defect to be worried about.

For the most part the mold will dissipate when the apples are taken from the carton and set out on display.  No mater the amount of mold present on the stem, the moldy stem is not considered a defect of any of the U.S. Apple Grades, including the top grade, U.S. Extra Fancy.  If you find mold affecting the calyx (the bottom of the apple) the same rules apply, “it is not a defect.” The USDA Inspection Instructions do state if the mold affects the flesh of the apple then the apple would be considered a defect.  Chances are the affected flesh would be soft, maybe mushy, which would mean the apple would be scored against the 1% tolerance for decay.

But this doesn’t mean you should totally ignore mold on the stems of apples.  You will want to cut a few apples in half and determine the extent of the mold.  You may notice the mold is not only present on the stem but it may also be present in the seed cavity.

If you do find mold in the seed cavity this is not to be ignored, as this is a defect of the U.S. Extra Fancy, U.S. Fancy and U.S. No. 1 Grades.  If the surrounding flesh is still firm, the moldy seed cavity would be scored against the 10% tolerance for defects.  If the surrounding flesh is soft, or mushy, the defect would be scored as decay, against the 1% tolerance.

The defect scoring of green onions, especially identifying discolored tops from decayed tops may get a little confusing, even for experienced inspectors.

With the green onions being packed in ice, to ensure their freshness, a side effect is the watersoaked and glassy appearance caused by the melting ice.  These watersoaked tops will sometimes be scored as decay.  Is there a good way to tell the difference?

The tops that are merely discolored may appear translucent, wilting and even wet to the touch.  If when rubbing the discolored top between your fingers, the tissue does not disintegrate, or slough off, the top is only scored as being discolored.  The green onion pictured above is a defect, scored a discoloration.  Once you have decided to score the top as discoloration you now determine if the defect is damage (materially affecting the appearance) or serious damage (seriously affecting the appearance).  The top pictured above is serious damage, by discoloration.  You would count out 50 individual green onions, not bunches, and separate the defects.  If you had three onions, out of 50 inspected, with serious damage by discolored tops, you would have 6%.  The U.S. Grade Standard allows up to 5%  for serious damage, so the onions would fail to grade.

If the top is watersoaked, but sloughs off when touched or rubbed, then the top is scored as decay.  The green onion pictured above would be scored as decay, affecting the tops.  The U.S. Grade Standard allows 2% for decay, so if you inspected 50 individual green onions, and 2 had decayed tops, you would have 4% decay…..failing to grade U.S. No. 1, exceeding the 2% tolerance for decay.

The one thing I have always loved about the fresh produce industry is the unexpected.  During a recent training class, where I had opened the session up to questions of all kind, I was asked if new top growth was a defect for topped carrots.

Not wanting to guess I opened up the USDA Inspection Instructions to find the correct answer.  I was expecting a far different answer than what I read.  For practically all commodities the USDA gives specific, almost ridiculous scoring guidelines for defects.  The U.S. Grade Standard may state you are allowed an area  of 5/8 of an inch (not 1/2 inch, but 5/8), 3/16 of an inch (not 1/4 inch but 3/16) and my favorite of allowing 3% of the surface (not 5% of the surface but 3%).   But the USDA inspection instructions for new top growth on topped carrots provided a bit of honesty, very refreshing.  The handbook states, “An occasional specimen showing new top growth in excess of 1 inch would have very little effect on the appearance of the lot.  On the other hand an appreciable amount of roots showing new top growth in excess of 1 inch would materially affect the appearance of the lot should be scored.”

To translate, if you have a carrot here and there with new top growth in excess of 1 inch, don’t worry about it.  But if you have quite a few carrots with new top growth in excess of 1 inch then by all means this new growth is a defect.  This is a strange way to give instructions on whether a carrot should be scored as a defect, or should be ignored.  Lots of room open for interpretation.

Let’s see if I can help.  The tolerances for defects for carrots is 10%.  So if you have a few carrots here and there, you most likely will not exceed the tolerance of 10%, so it really makes no difference if you score the carrot as a defect or not.  On the other hand if you have more than a few carrots here and there, with new top growth, you will more than likely exceed the 10% tolerance for defects.  Make it easy on yourself, if you find a carrot with new top growth, in excess of 1 inch in length, set it aside and score it as a defect.  The 10% tolerance will determine if the lot is materially affected, or not.  If you have less than 10% defects, the lot is in grade; if you have more than 10% defects then the lot will fail to grade.  Now isn’t that easier? ( Just be thankful the USDA set the scoring guideline to be in excess of 1 inch in length instead of 15/16 of an inch in length).

When inspecting peaches, or any stone fruit, there are a few defects you should always be on the look out for.  Decayed spots, soft areas from being overripe, and  bruising.  Bruising is the most common defect found on peaches, and peaches packed in volume-filled containers have a better chance of becoming bruised than tray pack peaches.

Identifying a bruise is fairly simple.  Look for a soft, depressed area, which may or may not be discolored.  On riper fruit the bruised area is usually discolored.  On hard to firm fruit the area may be depressed, or soft, but may not be discolored.  But if you take you knife and cut slightly under the skin the bruised area will most likely show discolored or watery flesh.  Measure the area of the bruise, and if the area is larger than 1/2 inch in diameter, or extends deeper than 3/16 of an inch, is scored as damage.  Bruising is a condition defect, so if you need to request a USDA inspection due to bruising, requesting a “Condition Only” inspection will be all that you need, saving you some extra inspection fees in the process.

One of the topics I always mention during my training classes is being able to identify the bruised area from decay.  It is much easier to demonstrate than it is to explain; but if you take your finger and wipe it across the discolored area just once, and the skin sloughs off, the spot is decay, and not a bruise.  Bruised/decayed areas on the blossom end are frequently encountered, and are easily confused,  but if you follow this simple procedure you should be able to distinguish between the two.