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U.S. Department of Health and Human Services

Food

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MPM: V-9. Fruits and Fruit Products (V-51 to V-78)

Contents

  1. Method for Canned and Frozen Fruits (V-51)
  2. Method for Dried Fruits (V-53)
  3. Method for Grape Products (V-59)
  4. Methods for Jams, Preserves, and Jellies (V-61)
  5. Method for Lingonberries (V-64)
  6. Method for Mincemeat (V-66)
  7. Method for Olives (V-67)
  8. Method for Pineapple Products (V-73)
  9. Method for Raisins (V-76)
  10. Method for Processed Strawberries (V-78)

E. Method for Canned and Frozen Fruits (V-51)

(1) Scope

This method describes a procedure for the examination of canned and frozen fruits to determine.

  • Percent of fruit damaged by insects and molds
  • Amount of extraneous matter present in the product

(2) Applicable Documents

  1. CPG 7110.02 Defect Action Level for Apricots
  2. CPG 7110.15 Defect Action Level for Lingonberries
  3. CPG 7110.22 Defect Action Level for Peaches
  4. CPG 7110.26 Defect Action Level for Plums

(3) Defects

Fruits may be damaged by pre- and post-harvest rots caused by molds and other microorganisms. In addition, insects may attack and damage fruit during growth, harvest, transport, and storage. Such types of damage, as well as the presence of extraneous matter, may occur in the finished product if the raw fruit is not properly prepared and processed under sanitary conditions.

(4) Procedure: Determination of Percent of Insect-Damaged and Moldy Fruit and of Presence of Extraneous Matter

  1. Sample Preparation -- Determine net weight of fruit in each container or subsample. Transfer contents to a suitable size flat pan for visual examination of individual fruits or pieces (thaw if necessary).
  2. Classification of Insect-Damaged and Moldy Fruit -- Classify damaged fruit as follows:

    1. (i) Insect-Damaged -- Any fruit or piece of fruit containing one or more whole insect(s) or equivalent or insect frass. Also classify any fruit exhibiting definite evidence of insect feeding as insect-damaged.
    2. (ii) Moldy or Decomposed -- Any fruit or piece of fruit exhibiting mold on one-fourth (1/4) of the inner or outer surface of the fruit or any fruit affected by mold over an aggregate area greater than the area of a circle 12 mm in diameter.
  3. Visual Examination for Insect and Mold Damage -- Examine each individual fruit unit (whole, half, slice, or piece) under good lighting for evidence of damage by insects or molds. Classify according to categories in (4) b. As appropriate, count or weigh reject fruit and passable fruit. Drain and rinse with water on suitable size sieve, collecting rinse water with packing medium for further examination for extraneous matter.
  4. Microscopic Examination for Extraneous Matter -- Filter packing medium and rinse water. If filtration is slow or too much debris is present for microscopic examination, transfer to one or more 2 L trap flasks. Extract as in AOAC 970.66B(a), using water and 35 L heptane [III.(7)]. Examine filter papers microscopically and classify extraneous matter according to applicable categories in AOAC 970.66(B)(i).
  5. Report -- Tabulate percent of insect-damaged and mold-damaged fruit by count or weight, as appropriate. Report extraneous matter as numbers per unit weight of container or subsample.


 


F. Method for Dried Fruits (V-53)

(1) Scope

This method provides a procedure for sample preparation and visual examination of various kinds of dried fruits to determine the percent of reject fruit damaged by insects, molds, and other causes. The method is applicable, but not limited to, fruits prepared in the following ways:

  • Apples (Malus sylvestris Mill.) are peeled, cored, sliced, and dried artificially, and frequently treated with sulfur dioxide.
  • Apricots (Prunus armeniaca L.) are picked when ripe and either sun-dried or artificially dried. They may be blanched with burning sulfur or a bisulfite solution.
  • Dates (Phoenix dactylifera L.) are grown in hot, dry regions and usually do not require artificial drying.
  • Figs (Ficus carica L.) can be allowed to ripen and partly dry on the trees. Processing may include fumigation, washing, and bleaching with sulfur dioxide, followed by additional drying. Smyrna-type figs require pollination by the fig wasp [Blastophaga psenes (L.)]. Other kinds will ripen without pollination.
  • Peaches and nectarines [Prunus persica (L.) Batsch] are halved, pitted, usually exposed to sulfur fumes, and then either sun-dried or artificially dried. Nectarines are merely smooth-skinned varieties of peaches.
  • Pears (Pyrus communis L.) may be halved, peeled, and sliced, or peeled, halved, and cored before sulfuring and dehydration either by the sun or by artificial means.
  • Prunes are the dried fruit of certain varieties of the European plum (Prunus domestica L.). Current industry practice involves heat-drying the prunes in dehydrators.

(2) Applicable Documents

  1. CPG 7110.09 Defect Action Levels for Dates and Date Material
  2. CPG 7110.10 Defect Action Levels for Figs
  3. CPG 7110.27 Defect Action Levels for Dried Prunes

(3) Defects

Defects in dried fruits are generally due to insect damage or mold and fungal decay. In some instances, dried fruits have been found contaminated by sand and soil particles and animal filth. Since the sources of the most likely defects vary with the type of fruit, this section discusses major defects for each fruit separately.

  1. Apples -- Insect-damaged parts may not be removed when slices are prepared, and improper handling of the dried product may lead to contamination with flies or storage insects, and with rodent or other filth. See Section 9.A(3) for a description of some insects which attack apples.
  2. Apricots -- The plum curculio [Conotrachelus nenuphar (Herbst)] may damage the fruit by egg laying and by both adult and larval feeding. Larvae of the oriental fruit moth [Grapholita molesta (Busck)] and peach twig borer (Anarsia lineatella Zeller) feed on and damage the fruit. Dried or drying apricots have been found to be commonly infested with Indianmeal moth [Plodia interpunctella (HØbner)], almond moth [Cadra cautella (Walker)] and Australian spider beetle (Ptinus ocellus Brown).
  3. Dates -- While on the tree, dates may be attacked by two scale insects, the parlatoria date scale [Parlatoria blanchardi (Targioni-Tozzetti)] and the red date scale (Phoenicococcus marlatti Cockerell) and less commonly by ants and grasshoppers. After drying and packaging, dates may be attacked by Indianmeal moth [Plodia interpunctella (HØbner)], almond moth [Cadra cautella (Walker)], driedfruit beetle [Carpophilus hemipterus (L.)], corn sap beetle [Carpophilus dimidiatus (Fabricius)], sawtoothed grain beetle [Oryzaephilus surinamensis (L.)], and navel orangeworm [Amyelois transitella (Walker)]. The presence of feathers or feces indicates contamination by birds or rodents. Rain may cause dates to ferment on the tree, leading to a condition called souring.
  4. Figs -- Numerous insects and several mites attack figs in the green, ripe, and dried stages. Yeasts, fungi, and bacteria also attack figs. Endosepsis is a condition brought about by infection with the fungus Fusarium moniliforme (Sheld.) which is transmitted by the fig wasp. An endoseptic fig has a "wet dog" odor, and its pulp looks dark and dull. Several species of fungi produce "smutty" figs. Another disease of figs is commonly termed souring. It is due to enzymatic fermentation of sugars in the ripened fig by yeasts, fungi, or bacteria. Sourness is identified organoleptically. Figs may also be contaminated with soil, stones, or rodent or bird excrement.
  5. Peaches and nectarines -- Insects which attack the fruit while still on the tree include plum curculio [Conotrachelus nenuphar (Herbst)], oriental fruit moth [Grapholita molesta (Busck)], tarnished plant bug [Lygus lineolaris (Palisot de Beauvois)] and others. Drying or dried fruit may be attacked by the nitidulid beetle [Haptoncus luteolus (Erichson)], navel orangeworm [Amyelois transitella (Walker)], raisin moth [Cadra figulilella (Gregson)], or Indianmeal moth [Plodia interpunctella (HØbner)]. Peaches and nectarines are also susceptible to black spot or scab, caused by Cladosporium carpophilum, frosty mildew, due to infection with Mycosphaerella persica, and brown rot, caused by Monilinia fructicola (Wint.) Honey, which enters through feeding punctures of curculio.
  6. Pears -- During growth, pears may be damaged by the apple maggot [Rhagoletis pomonella (Walsh)] and by species of thrips, psylla, moths, and curculios. The dried fruit may be attacked by several beetles and by Indianmeal moth [Plodia interpunctella (HØbner)]. Diseases include blue mold rot, caused by Penicillium spp.; brown rot, caused by Monilinia fructicola (Wint.) Honey; bull's-eye rot, due to Neofabraea spp.; core breakdown (internal breakdown, core rot, brown heart), and gray mold rot, caused by Botrytis spp., one of the most serious storage diseases.
  7. Prunes -- Plums may be attacked on the tree by the oriental fruit moth [Grapholita molesta (Busck)], lesser appleworm [(Grapholita prunivora (Walsh)], several species of aphids, plum curculio [Conotrachelus nenuphar (Herbst) and a leaffooted bug [Leptoglossus phyllopus (L.)]. In storage, prunes may be damaged by driedfruit moth (Vitula edmandsae serratilineella Ragonot), the navel orangeworm [Amyelois transitella (Walker)], raisin moth [Cadra figulilella (Gregson)], dried prune moth [Aphomia gularis (Zeller)], sawtoothed grain beetle [Oryzaephilus surinamensis (L.)], and merchant grain beetle [Oryzaephilus mercator (Fauvel)]. While drying, rotten or overripe fruit may contain dried fruit beetle [Carpophilus hemipterus (L.)], corn sap beetle [Carpophilus dimidiatus (Fabricius)], or yellow nitidulid [Haptoncus luteolus (Erichson)]. Additionally, the fruit may show evidence of Monilinia fructicola (Wint.) Honey, a brown rot, or Septoria sp., called the shot hole fungus. Several of the insects mentioned above will spread fungi and yeasts in the course of their feeding and breeding activities. Amber or light-colored flesh with a solid texture is one of the characteristics of quality. Texture may vary from solid to the extreme of porosity in which one or more large air pockets occur (bloaters).

(4) Procedure: Determination of Insect-Damaged, Moldy, and Otherwise Reject Dried Fruit

  1. Classification of Reject Fruit

    1. (i) Insect-damaged -- Any fruit containing one or more whole insect(s) or equivalent, insect webbing or excreta, or exhibiting definite evidence of insect feeding. Determine, if possible, whether infestation is "orchard" or "storage" and report separately. Include size and kind of insects found.

      Orchard infestation results from the attack of insects before the fruit is harvested and dried. Such attack may be evident as tunnels, pockets of gum in stone fruits, discoloration where feeding has occurred and pronounced damage in the pit cavity of some fruits.

      Storage infestation results from insects attacking the fruit during and after drying. Storage pests may contaminate the fruit by the presence of whole insects, cast skins, webbing, and excreta that are not dried down into the fruit. Tunnels or insect-chewed pockets with adhering insect matter may be readily visible on the surface of the dried fruit.

    2. (ii) Mite-damaged -- Any fruit showing obvious presence of mites. Mites may be detected by the dusty, sugary, or encrusted appearance of the dried fruit, by the presence of their dirty white, glistening, or dull-appearing bodies and sometimes by the movement of living mites in the sample when a widespread infestation of the sample has occurred. Confirm suspected mites microscopically and identify if possible.
    3. (iii) Moldy or decomposed -- Any fig-bearing mold over an area that exceeds a circle 5 mm in diameter, or any fig with a sour odor or flavor or darkening and internal rot indicative of endosepsis. Classify any other dried fruit or prune as moldy or decomposed when 1/4 of the fruit is affected or the aggregate affected area is greater than 1 cm2.
    4. Brown rot of stone fruits appears as a central decayed spot surrounded by concentric rings and pustule-like elevations. The spores, in chains, have a characteristic barrel shape. Bin mold, caused by the fungus Geotrichum candidum (Link) occurs as a white filamentous growth over the surface of prunes. Other types of moldy or decomposed areas may be accompanied by a sour or fermented odor.
    5. (iv) Dirty -- Any dried fruit with an appreciable amount of sand, soil, cinders, etc. When a smear of fine dirt particles is the criterion, it should cover 1/4 of the fruit area or an area greater than 1 cm2. Fruit contaminated by larger individual dirt particles, especially those that would be detected upon chewing, should be classified as "dirty" even when the affected area is less than the requirement for fine particles.
    6. (v) Otherwise unfit -- Any dried fruit that is so immature, grossly fibrous or woody that it is valueless for food purposes. Do not classify fruit under this heading that is simply tough or of a somewhat undesirable quality.
  2. Sequential Analysis Plan for Dates [Editor's Note: The following table has been revised from the original to reflect current policy found in CPG 550.300]
    Number of Dates ExaminedaAccept
    (at or below)
    Number of Defective Dates
    ContinueAnalysisReject at or above
    10012-78
    20056-1213
    3001011-1718
    4001415-2122
    5001819-2526
    6002324-3031
    7002728-3435
    80034---35
    a Product is to be selected at random and as nearly equal in number as practical from each subsample in the sample.
  3. Sample Preparation and Visual Examination -- Classify all fruits according to (4)a.

    1. (i) Dates, whole -- Follow the sequential sampling plan in (4)b. Cut each date open and examine with a magnifier for pits, pit fragments, insect-damage, mold and decomposition, dirt, and any other damage which would make the fruit unfit for food. Check doubtful defects microscopically.
       
    2. (ii) Figs -- Analyze six subsamples of 100 fruits each. Open each fig by inserting a knife into the eye, splitting down the sides, and pulling apart. Examine with magnifier as necessary. Confirm doubtful areas microscopically. Do not classify fruit with fig wasps as rejects.
    3. (iii) Prunes -- Examine a minimum of ten subsamples. Place prunes in large white enamel pan, or in white enameled muffin pan, and add sufficient water to cover fruit. If muffin pans are used, place one fruit in each depression; if flat pans are used, arrange fruits so that they are sufficiently far apart that residues from adjacent fruits will not become mixed. Soak overnight and examine for defects with magnifier, confirming doubtful areas microscopically. For pits in pitted prunes, examine a minimum of 50 prunes from each of ten subsamples from each code, or from the lot if no codes are present.
    4. (iv) Raisins -- Use the method described in Section 9.M.
       
    5. (v) Other fruits -- Analyze six subsamples of 100 fruits each. Cut each fruit open. Use a magnifier and confirm doubtful areas microscopically.
  4. Report -- In reporting results, if a piece falls into more than one reject classification, classify it under the heading first listed in the table. Explain, by footnote to a particular subsample number or by generalization as to the whole sample, the condition of the rejects so that the reviewing officer will have a word picture of the condition of the sample as seen by the analyst.

    Tabulate results as follows:

     Product Subsample No.
    123etc.Average
    Number Examined     
    Insect Infested (Orchard)     
    Insect Infested (Storage)     
    Moldy or Decomposed     
    Dirty     
    Otherwise Unfit     
    Prunes Only
      Number of prunes with whole pitsa
      Number of prunes with pit fragments 2 mma
         
    No. of Units Showing Mitesb     
    Total No. Rejects     
    Total % Rejects     

    Remarks:


     

         
    Notes:
    a Report dimensions in mm
    b Describe condition of entire subsample

Reference

Simmons, P. and H. D. Nelson, Insects on Dried Fruits, USDA Agricultural Research Service, Handbook 464, Washington, DC, 1975.

 


 


G. Method for Grape Products (V-59)

(1) Scope

This method describes a macroscopic procedure for the determination of insect damage in stemmed and crushed grapes destined for further processing into grape juice, grape pulp for jam or production of wine. The macroscopic procedure is particularly applicable to damage by the grape berry moth. Also included with this method are two microscopic procedures. Determination of rot in the crushed grapes or in the grape pulp requires a microscopic, mold mycelia count procedure. Determination of extraneous filth in these semi-processed products may also require a microscopic procedure utilizing a flotation recovery technique.
 

(2) Applicable Documents

(3) Defects

  1. Insect Infestation and Damage -- A variety of pests can infest and damage grapes. Grape berry moth larvae (Endopiza viteana Clemens) eat their way into the berries and feed on pulp and seeds. The rose chafer [Macrodactylus subspinosus (Fabricius)] feeds on flowers, leaves, and fruits. The grape mealybug [Pseudococcus maritimus (Ehrhorn)] withdraws sap and produces honeydew which spots leaves and fruits and serves as a growth medium for sooty fungi, which forms a dusty coating on the grapes. The grape curculio [Craponius inaequalis (Say)] sometimes feeds on berries and inserts its eggs in cavities gnawed beneath the skin of the fruit; the larvae feed on the flesh and seeds. Decayed and crushed grapes may attract and provide a breeding ground for large numbers of Drosophila flies in the harvested fruit, resulting in severe contamination with eggs and maggots.
  2. Moldiness and Fungal Deterioration -- Rot due to molds may develop before or after harvesting.
  3. Extraneous Filth -- Grape products may be contaminated by extraneous matter such as insect or rodent excreta.

(4) Procedure: Macroscopic Determination of Insect-Damaged Stemmed and Crushed Grapes (Not Heat-Processed)

  1. Sample Preparation -- Use approximately 1 L of subsample and weigh. Spread out subsample in a large flat pan to expose individual grapes and pieces.
  2. Visual Examination -- Examine grape material in good lighting; remove insect-damaged grape material and weigh; remove insects and identify.
  3. Report -- Report percent by weight of insect-damaged grape material. Also report number, size, and identity of insects found.

(5) Procedure: Determination of Rot in Stemmed and Crushed Grapes (Not Heat-Processed) by Mold Count

  1. Sample Preparation -- Pass approximately 1 L of each subsample through laboratory cyclone as in AOAC 945.75B(g) and mix thoroughly.
  2. b. Analysis -- Make mold count on the undiluted grape pulp of each subsample as in AOAC 965.41.

(6) Procedure: Determination of Insect and Rodent Filth in Stemmed and Crushed Grapes (Not Heat-Processed) by Flotation

Measure each subsample up to 1 L and transfer to a 2 L trap flask, AOAC 945.75B(h)(4). Extract as in AOAC 970.66B(b), using water and 35 mL heptane, III. 7. Examine filter papers and report extraneous matter as numbers per unit weight of container or subsample.

(7) Procedure: Determination of Rot in Grape Pulp by Mold Count

  1. Sample Preparation -- Weigh 100 g of well-mixed pulp in blender following AOAC 945.75B(c). Add 100 mL 0.5% NaOH solution and mix for 3 min. If necessary, break foam by adding 2-3 drops capryl alcohol and stirring. Add 20 g blended pulp to 20 g stabilizer solution [III. (15)] and mix thoroughly.
  2. Mold Count -- Make mold count as in AOAC 984.29.


 


H. Methods for Jams, Preserves, and Jellies (V-61)

(1) Scope

Jams, preserves and jellies contain varying amounts of fruit tissues in the product. Visible decomposition or filth in the fruit is generally altered by the processing; thus, more indirect microscopic methods are required for evaluation of these defects. Economic violations may include the substitution of apple fruit tissue for the declared fruit or the addition of berry seeds to the declared fruit in the product.

These methods describe procedures applicable to the analysis of jams, preserves, and jellies. These include the following procedures:

  • Determination of decomposed fruit by the mold mycelia count technique
  • Determination of filth by flotation
  • Determination of foreign ingredients by microscopic analysis based on diagnostic cellular structures and morphological features

(2) Applicable Documents

  1. CPG 7110.12 Defect Action Level for Mold Count of Cherry Jam
  2. CPG 7110.13 Defect Action Level for Mold Count of Black Currant Jam

(3) Defects

Improper control of raw material and other poor manufacturing practices may result in the presence of mold or insect or rodent filth in the products. Jams and preserves may occasionally be adulterated by the addition of apple or other fruit tissue, which can be detected microscopically. Also, some samples of preserves have been found to be adulterated by the addition of berry seeds to mask a deficiency in berry pulp.

(4) Procedure: Determination of Rot by Mold Count in Blackberry, Raspberry, and Other Drupelet Berry Jams and Preserves

  1. Sample Preparation and Mold Count -- Pulp the entire subsample, if 2 lb or less, through a laboratory cyclone [AOAC 945.75B(g)]. If the subsample is over 2 lb, pulp a representative portion of about 2 lb and mix. Weigh 50 g stabilizer solution [III. (15)] in a 250 mL beaker. Add 10 drops capryl alcohol (2-octanol) to 50 g of the pulped jam or preserves and mix thoroughly. Apply suction and shake gently until most of the air bubbles are removed (5-10 min). Suction may be applied to the beaker by placing a bell jar over it or by transferring the material to a suction flask. Mix subsample thoroughly and make mold count as directed in AOAC 984.29.
  2. Report -- Report as in AOAC 984.29.

(5) Procedure:Determination of Rot by Mold Count in Strawberry and Other Fruit Preserves or Jams

  1. Sample Preparation and Mold Count -- Pulp and mix subsample as in (4)a. above. Add about 100 g pulped material to a 250 or 500 mL suction flask. Heat the flask gently under vacuum until most of air the bubbles are removed from the jam or preserves, or remove air bubbles as in (4)a. Mix the subsample thoroughly and make mold count as directed in AOAC 984.29.
  2. Report -- Report as in AOAC 984.29.

(6) Procedure: Determination of Filth in Preserves, Jams, and Jellies

Use AOAC 950.89 for light filth, (a) for jam or preserves and (b) for jelly.

(7) Procedure: Determination of Apple and Other Underclared Fruit Tissue in Jams and Preserves

  1. Sample Preparation -- Mix subsample thoroughly and weigh out 25 g. Add weighed subsample to about 150 mL water and stir. Let stand about 5 min with occasional stirring. At the end of this time, stir throughly and transfer the solution to several petri dishes. The coarse tissue should be distributed in a thin layer over the bottom of each dish.
  2. Visual Examination -- Examine each dish, using a widefield microscope. Apple skin tissue is detected by the presence of tightly rolled bits of tissue. Examination of this tissue under the compound microscope shows quadrilateral cells in window-type grouping. Apple pulp cells usually can be identified by large sac-shaped cells loosely grouped together in small masses. This procedure can also be used for the detection of other undeclared fruit tissues. Refer to the data on microscopic structure and diagnostic characteristics of suspected adulterants as described in Winton's Structure and Composition of Foods, and compare with microscopic examination of authentic specimens.
  3. Report -- Report any foreign plant tissue that is present as an apparently undeclared ingredient. Identify if possible. Estimate percent of foreign tissues by microscopic comparison with mixtures containing known percentages of authentic ingredients.

(8) Procedure: Determination of Seeds Added to Strawberry, Raspberry, or Blackberry Preserves to Mask a Deficiency in Fruit Tissue

  1. Sample Preparation and Visual Examination -- Mix the subsample throughly and weigh out about 10 g into a 150 mL beaker. Add sufficient water to fill beaker, stir, and allow to stand 10 min. Decant the floating tissue, taking care not to decant any of the seeds. Remove a small portion of the seeds to a petri dish, cover with water, and examine with a widefield microscope, using low magnification. Make a separate count of naked and covered seeds. Classify as "naked" those seeds which are free of fruit tissue. In preserves made from the normal amount of whole fruit the percentage of naked seeds is negligible. Count all the seeds in the petri dish. Repeat this process until ten 10 g portions have been examined.
  2. Report -- Report total number of seeds, number of covered seeds, and number and percent of "naked" seeds.

Reference

Winton, A. L., and K. B. Winton, "Vegetables, Legumes and Fruits," Structure and Composition of Foods, Vol. 2, John Wiley and Sons Inc., NY, 1935.


 


I. Method for Lingonberries (V-64)

(1) Scope

This method is designed to recover moth larvae (caterpillars) from lingonberries by a flotation procedure. The method is applicable to the canned and frozen product consisting of essentially whole or comminuted fruit. The lingonberry (Vaccinium vitis-idaea L.), also called mountain cranberry and cowberry, grows in northern regions of the Eastern and Western hemisphere. It resembles a cranberry.

(2) Applicable Documents

  1. CPG 7110.15 Defect Action Level

(3) Defects

Lingonberries may be infested with maggots and moth larvae. Maggots are determined by AOAC 945.78, a microscopic sedimentation procedure. Moth larvae float and require a different procedure. Some of these larvae are external, floating free in the juice or clinging to the outside of the berry. Others are internal and not readily apparent.

(4) Procedure: Determination of Moth Larvae and Other Insect Matter in Lingonberries

  1. Sample Preparation -- Place 1 lb of lingonberries or sauce in a suitable deep container (No. 10 can or equivalent). Fill with water to within about 1 in. from the top. Thaw the berries if frozen. Stir several times and pick out the larvae which float to the surface. Pour the mixture onto a No. 6 sieve nested in a No. 40 sieve. Rinse the berries on the No. 6 sieve with water, passing the rinse water through the No. 40 sieve.
  2. Visual Examination and Pick Out -- Remove the material from the No. 40 sieve into a white pan and examine under good lighting. Pick out insect larvae and other insect matter. Boil the berries retained by the No. 6 sieve for about 20 min, cool, and mash through the No. 6 sieve. Mix the mashed material with saturated salt solution in a large container. Stir several times and pick out the floating larvae and other insect matter.
  3. Report -- Tabulate results as follows:
    Code No. ______Subsample No.
    123etc.Average

    External Larvae
    (from material on #40 sieve)

    Cast skins with heads

    Larvae

         

    Internal larvae
    (from the #6 sieve)

    Cast skins with heads

    Larvae

         
    Other insectsa     

    Remarks:


     

         
    Notes:
    a Report identity under remarks


 


J. Method for Mincemeat (V-66)

(1) Scope

This method describes a microscopic procedure to determine insect matter, rodent hairs, and other extraneous material in mincemeat by flotation recovery. Mincemeat is a mixture of finely chopped fruits, spices, and other ingredients combined in varying proportions; meat and suet may or may not be components.

(2) Applicable Documents

(3) Defects

Mincemeat may be contaminated with filth consisting of insects, insect fragments, rodent hairs, and other extraneous matter. These defects may be present in the various raw materials used to produce mincemeat or they may be introduced during manufacture due to insanitary plant conditions.

(4) Procedure: Determination of Insects, Insect Fragments, Rodent Hairs, and Other Extraneous Matter in Mincemeat

  1. Sample Preparation and Flotation Recovery -- Weigh 100 g subsample into 400 mL beaker. Add 150 mL hot water and stir. Pour mixture from beaker onto 140 mesh screen and wash well with hot water. Transfer all material from sieve to a 1 L trap flask (AOAC 945.75B(h)(4)). Add 200 mL 80% alcohol and boil 5 min. Cool to room temperature and add 50 mL of heptane (III. (7)). Following AOAC 970.66B(b), mix thoroughly and let stand 5 min; fill flask with 80% alcohol, trap off, and filter. Examine microscopically.
  2. Report - Tabulate results according to format and applicable categories in AOAC 970.66B(i).


 


K. Method for Olives (V-67)

(1) Scope

This method includes procedures for sample preparation and visual examination of olives to determine the percent of reject olives due to fungal (mold) decomposition, insects, or the presence of pits and/or pit fragments.

Olives, the fruit of Olea europaea L., contain a bitter glycoside which must be removed to make them edible. Many processing methods are used locally in olive growing regions, but there are three major commercial methods:

  • Spanish-type green olives are made from unripe fruit which is treated with lye to remove the bitter substance, rinsed, and soaked in water, and then subjected to a lactic acid fermentation in salt solution
  • California-type ripe olives are made from half-ripe fruit which is also lye-treated and leached in water, and then cured briefly without fermentation in a salt solution before being canned
  • Greek-style or salt-cured ripe olives are made from fully ripe fruit which loses its bitterness without lye treatment by undergoing a slow fermentation (curing) by contact with dry salt. After proper curing, the olives are coated with olive oil. Another type of Greek ripe olives is prepared by fermentation in 10% brine.

(2) Applicable Documents

  1. CPG 7110.19 Defect Action Levels for Olives

(3) Defects

  1. Insect Infestation and Damage -- Honeydew excreted by the black scale [Saissetia oleae (Olivier)] may drop on the fruit and encourage the growth of sooty mold, which creates difficulties in harvesting and processing. Olive scale [Parlatoria oleae (Colvee)] and oleander scale (Aspidiotus nerii Bouche) may damage the fruit directly, causing dark spots and deformity. The olive fruit fly [Dacus oleae (Gmelin)] deposits its eggs in the flesh through the skin. On green olives, a small black spot marks the site of oviposition. On green pickled olives, there may be a slightly sunken gray spot about 1 mm in diameter, sometimes with the skin broken. The maggot forms tunnels, and on examination of brined green olives, maggots and pupae may be found inside. Ripe olives are more likely to show excessive damage because the fruit remains on the tree longer. The olive fruit fly has not been a problem to date in olives grown in the United States.
  2. Moldiness and Fungal Decay -- Molds may attack the fruit in the orchard, during transit and storage, and during processing, but they have not been a serious problem with most trade-type olives. Salt-cured olives have the potential to develop a mold problem if the salt treatment is not conducted properly. An anthracnose-type infection (Melanconiales) sometimes occurs, showing characteristic skin lesions in the form of pustules.
  3. Pit Fragments -- Pit fragments may be found in pitted olives or in salad olives (olive pieces).

(4) Procedure: Determination of External and Internal Rot in Salt-Cured (Greek Style) Olives

  1. Sample Preparation -- Examine a minimum of 6 subsamples from each code or from the lot if no codes are present. Place olives in a flat pan of suitable size and mix thoroughly. Count out, at random, 100 olives and transfer to a flat, white-bottom pan (approximately 10 in. x 14 in. x 2 in.) containing hot water to which 1 teaspoonful of soap powder or trisodium phosphate has been added. Stir gently and thoroughly until most of the oily coating has been removed. Transfer the olives to a No. 6 or 8 sieve and rinse with hot water. Return the olives to the white-bottom pan and cover with water.
  2. Examination for Presence of External Rot -- External rot will appear under water as light-brown or tan colored areas, soft or mushy areas, areas having cracked and broken skins, or areas having small black pustules (fruiting bodies of anthracnose fungus). Where one or more of the above conditions are observed, examine the internal tissue from the questionable area by removing a small portion with tweezers. Place on a slide in a drop of water. Remove another piece of internal tissue from a point opposite the questionable area on the other side of the olive. Place this piece of the olive on the same slide in another drop of water. Examine both portions at 100-200X and classify olives according to the extent of mold damage listed in (4)d.
  3. Examination for Presence of Internal Rot -- Examine remaining olives by making a slice in cross-section through of the olive at its midpoint. Pull one side of the section away from the cut and, with a razor blade, make as thin a slice as possible of a cross-section through the epidermis and underlying tissues. Place this section in a drop of water on a slide. Turn the olive over and make a similar slice on the side opposite the first cut. Mount in another drop of water adjacent to the first one, on the same slide. Macerate olive tissues and place cover slips over sections. Examine both portions microscopically at 100-200X and classify olives according to the extent of mold damage listed in (4)d.
  4. Classification of Mold Damage -- Classify mold damage as follows:

    1. (i) Less than 1/4 of the olive affected -- an olive which contains a few scattered hyphae in a single cross-section or portion
    2. (ii) 1/4-1/2 of the olive affected -- if mold filaments are widely scattered in one cross-section or portion
    3. (iii) the olive or more affected -- if both cross-sections or portions of the olive contain widely scattered mold filaments.
  5. Report -- Tabulate results as follows:
     Subsample No.
    12etc.
    Number of olives with external decomposition affecting:Less than 1/4 of the olive   
    1/4 - 1/2   
    1/2 or over   
    Number of olives with internal decomposition affecting:Less than 1/4 of the olive   
    1/4 - 1/2   
    1/2 or over   

    Remarks:


     

        

(5) Procedure: Determination of Pit Fragments in Whole Pitted Olives

  1. Sample Preparation -- Mix the subsample thoroughly and count out 100 or more olives. Cut open each olive to expose the presence of any pits or pit fragments.
  2. Visual Examination and Classification -- Examine a minimum of 500 olives from each code or from the lot if no codes are present. Examine each olive and classify those with pit fragments or whole pits into the following categories:

    1. (i) Olive with a pit fragment measuring less than 2 mm in its longest direction
    2. (ii) Olive with a pit fragment measuring 2 mm or larger in its longest direction
    3. (iii) Olive with a whole pit
  3. Report -- Tabulate results as follows:
     Subsample No.
    12etc.Average
    No. of olives examined    
    No. of olives containing fragments less than 2 mm    
    No. of olives containing fragments 2 mm or more    
    No. of olives containing whole pits    

    Remarks:


     

        

(6) Procedure: Determination of Pit Fragments in Salad Olives (Green Olive Pieces)

  1. Sample Preparation -- Drain each subsample or individual consumer size container for 2 min on a #30 sieve. Separate olives and olive pieces from any stuffing and weigh olive material. Examine a minimum of 1,500 grams from each code or from the lot if no codes are present. Cut olives, as necessary, to expose the presence of any pits or pit fragments.
  2. Visual Examination and Classification -- Examine entire drained sample including stuffing for pits and pit fragments. Classify according to size of fragments shown in (6)c.
  3. Report -- Tabulate results as follows (300 g is equivalent to 100 Manzanilla size olives):
     Subsample No.
    123etc.
    Wt of olive material examined (g)    
    No. of pits or fragments
    2 mm
    2 mm or more
    whole
        
    Average No.
    Per 300 g
        

    Remarks:


     

        

(7) Procedure: Determination of Reject Green, Black, Salt-Cured, and Salad Olives Due to Damage by Dacus and Scale Insects

  1. Sample Preparation and Visual Examination -- Examine a minimum of 6 subsamples from each code or from lot if no codes are present. Examine at least 50 olives per subsample for presence of scale insects on the surface of the fruit and for internal damage by Dacus. Examine a minimum of 1,500 grams of salad olives per subsample. After examination of each olive for surface contamination by scale insects, cut olive into thin slices parallel to the length of pit, using a sharp knife or scalpel to detect Dacus damage. Dacus damage is indicated by tunneling in the flesh, sometimes accompanied by the presence of maggot(s). Examine each olive for insect damage and classify according to (7)b. Classify the olive in the first applicable category if defects in more than one category are found.
  2. Classification of Insect Damage -- Classify results of examination as follows:

    1. (i) Dacus-damaged (maggot present ) -- Any olive containing the intact maggot of the olive fruit fly or part thereof.
    2. (ii) Dacus-damaged (tunneling only) -- Any olive showing maggot tunneling affecting an area 1/4 in. or greater average diameter.
    3. (iii) Scale insect-damaged -- Any olive showing 10 or more scale insects.
  3. Report -- Tabulate results as follows:
    Olive Type: (green olives, black olives, etc.)Subsample No.
    123etc.
    No. of olives examined    
    wt of olives examined (salad olives only)    
    Total no. of "Dacus damaged" olives
    No. with tunneling and maggots
    No. with tunneling only
        
    Percent by count of "Dacus damaged" olives    
    Percent by weight of "Dacus damaged" olives (salad olives only)    
    No. of olives that have 10 or more scale insects present on each    
    Average percent (by number) of olives with 10 or more scale insects each    

    Remarks:


     

        


     


    L. Method for Pineapple Products (V-73)

    (1) Scope

    This method, applicable to various pineapple products, specifies microscopic procedures for determining.

    • Molds and decomposition by the mold mycelia count technique
    • Insect matter by direct filtration or by oil flotation

    Methods for these determinations in pineapple juice are contained in AOAC. The AOAC methods for pineapple juice have been modified here to apply to various other pineapple products such as sliced, chunk, tidbit, crushed pineapple, and juice concentrate.

    The pineapple [Ananas comosus (L.) Merr.] is native to the American tropics but is now grown in all tropical regions. In the commercial canning of pineapples, inedible parts are removed by machine, forming cylinders of the fruit which are hand trimmed, spray-washed and sliced, or cut into other forms. Broken pieces or slices that are too thick or thin are used for crushed pineapple or juice. Shells and trimmings are pressed and used for juice, which may be refined, mixed with syrup, and added to canned pineapple.

    (2) Applicable Documents

    1. CPG 7110.24 Defect Action Level

    (3) Defects

    1. Insect Infestation -- The pineapple mealybug (Dysmicoccus brevipes (Cockerell)) is an important pest of pineapples. Sooty mold grows on the honeydew produced by the mealybug, reducing the market value of the fruit. Mealybug feeding is also responsible for pineapple wilt disease. The pineapple false spider mite (Dolichotetranychus floridanus (Banks)) can cause severe injury to young plants. The pineapple scale, grasshoppers, crickets, beetles, and other insects may be found feeding on mature fruits, but they are minor pests. Drosophila flies and dried fruit beetles are the most common insects infesting pineapple products after harvest.
    2. Moldiness and Fungal Deterioration -- Black rot of pineapples results from infection by the fungus Ceratostomella paradoxa, which enters at the surface of a freshly cut stem or at a bruise on the fruit. Mold from this source may contaminate juice and other pineapple products if the fruit is not properly sorted and trimmed. Canned pineapple products may be contaminated with fragments of Geotrichum mold by unclean factory equipment where the mold grows.

    (4) Procedure: Determination of Molds and Decomposition by Mold Count of Sliced, Chunk, and Tidbit Pineapple Products

    1. Sample Preparation -- Drain the pineapple on a No. 8 sieve of suitable diameter for 2 min. Save pineapple retained on sieve for (5)a. below.
    2. Mold Count -- Make mold count of the drained juice as in AOAC 970.75, returning the decanted supernatant liquid to the remaining drained juice, which is saved for (5)a. below.

    (5) Procedure: Determination of Insect Matter, Rodent Hairs, and Other Extraneous Material in Sliced, Chunk, and Tidbit Pineapple Products

    1. Sample Preparation and Microscopic Examination -- Wash pineapple from 4(a) above on the sieve with water, retaining the washings. Discard material on the No. 8 sieve. Pour washings and the original drained juice from (4)b. above onto a No. 140 sieve. Wash material retained on the No. 140 sieve and transfer to ruled filter paper. Examine filter papers microscopically.
    2. Report -- Classify and tabulate according to applicable categories in AOAC 970.66B(i).

    (6) Procedure: Determination of Molds and Decomposition by Mold Count of Crushed Pineapple

    1. Sample Preparation -- Drain the pineapple on a No. 14 sieve of suitable diameter for 2 min. Save pineapple retained on sieve for (7)a. below.
    2. Mold Count -- Make mold count of the drained juice as in AOAC 970.75, returning the decanted supernatant liquid to the remaining juice, which is saved for (7)a. below.

    (7) Procedure: Determination of Insect Matter, Rodent Hairs, and Other Extraneous Material in Crushed Pineapple

    1. Sample Preparation and Microscopic Examination -- Immerse the No. 14 sieve and contents from (6)a. above in a pan of water and agitate. Remove the No. 14 sieve from pan; invert and immerse in another pan of water to separate pineapple from sieve. Examine pineapple material macroscopically for insects and other filth. Record findings. Pour washings from the first pan and the drained juice from (6) b. above onto a No. 140 sieve. Wash material retained on the No. 140 sieve thoroughly and transfer to ruled filter, paper. If appreciable pineapple tissue remains on the No. 140 sieve, transfer contents to 2 L trap flask and extract, trap and filter, using 30 and 20 mL kerosene, AOAC 970.66B(b). Examine filter papers microscopically.
    2. Report -- Classify and tabulate microscopic and macroscopic findings according to applicable categories in AOAC 970.66B(i).

    (8) Procedure: Determination of Molds and Decomposition by Mold Count of Pineapple Juice Concentrate

    Make mold count on well mixed sample as is, using AOAC 984.29.

    (9) Procedure: Determination of Fly Eggs and Maggots in Pineapple Juice Concentrate

    Dilute concentrate with water according to directions on the container and proceed as in AOAC 970.72A.

    (10) Procedure: Determination of Insect Matter, Rodent Hairs, and Other Extraneous Material in Pineapple Juice Concentrate

    Dilute concentrate with water according to directions on the container and proceed as in AOAC 970.72B.


     


    M. Method for Raisins (V-76)

    (1) Scope

    This method covers procedures for examination of individual raisins to determine

    •  
    • Decomposition caused by molds and other means
    • Insect contamination
    • Contamination by sand and soil

    Raisins are the dried fruits from many varieties of the wine grape (Vitis vinifera L.). Certain small seedless raisins are called currants, although they are not related to the bush fruits of the genus Ribes, which are also called currants.

    Raisins may be produced by sun-drying or by artificial dehydration. Sometimes an alkaline dip is used before sun-drying to remove the waxy layer and hasten drying. For artificial drying, many different procedures have been used; these may involve a lye dip, a sulfur bleach, or both. After drying, raisin processing includes removal of dirt and debris, removal of stems, washing, dewatering, sorting, and packaging.

    (2) Applicable Documents

    1. CPG 7110.28, Defect Action Levels for Mold, Sand, and Grit, and Insects and Insect Eggs

    (3) Defects

    In addition to the insects which attack grapes on the vine, numerous insects may infest raisins in storage, including raisin moths [Cadra figulilella (Gregson)], dermestids, Indianmeal moths [Plodia interpunctella (HØbner)], driedfruit beetles [Carpophilus hemipterus (L.)], and sawtoothed grain beetles [Oryzaephilus surinamensis (L.)]. During periods of unfavorable weather, raisins left to dry in the sun may become moldy, and they may be damaged by fermentation, grit, sand, and soil. These defects may affect the edibility of the product.

    (4) Procedure: Determination of Rot in Natural Raisins Showing Catalase Activity

    This procedure is intended for use with raisins where catalase activity has not been destroyed by treatment with lye, oil, or heat.

    Count out 100 raisins from each well-mixed subsample and place 10 or 15 at a time in a crystallizing dish. Cover each lot with a fresh solution of 5% hydrogen peroxide and 1% NH4OH. The moldy areas are detected by the presence of copious oxygen bubbles. Place the crystallizing dish over black glazed paper to give greater contrast. Yeasts will also give a reaction with hydrogen peroxide. Do not classify these raisins as rejects. Confirm the presence of mold filaments microscopically. Count as rejects those raisins that show mold on more than 1/4 of the surface area. Report percent of rejects for each subsample and the average percent of rejects. Report the percent of partially moldy raisins (raisins that show mold on less than 1/4 of the surface area) separately.

    (5) Procedure: Determination of Rot in Bleached Raisins and Raisins Treated with Lye, Oil, or Heat

    Count out 100 raisins from a well-mixed sample or subsample. Place them in a 400 mL beaker, cover with water, heat to boiling, and boil about 5 min. Drain off water and place raisins in a white pan. Cover completely with water and examine with an ocular loupe or jeweler's eyepiece with magnification of about 5X. Pick out those raisins that are obviously moldy and any that are suspected of being moldy. Examine the latter microscopically to determine the presence or absence of mold filaments. Report moldy and partially moldy raisins as described above in (4).

    (6) Procedure: Determination of Post-Processing Insect Contamination in Raisins

    Examine entire contents of an 8 oz. retail package (225 g). Raisins from smaller packages of the same lot or code may be combined so that a composite sample can be examined. Place raisins in a white enameled pan where they can be spread out and examined; note presence of any live insects. Confirm identification microscopically. Report number of whole insects (dead or alive) or equivalent and identify. Also report other insect evidence such as excreta, holes in packaging material, etc.

    (7) Procedure: Analysis for Sand and Soil in Raisins

    Weigh out 100 g from well-mixed sample or subsample. Cover with water and boil about 5 min. Pour the raisins into a No. 10 sieve and rinse with a fine stream of water, catching all the water. Allow to settle 10-15 min. Decant the upper portion of the water and then filter the residue through an ashless filter paper. Ignite the filter in a tared crucible at about 500 and weigh to determine sand and dirt. Report as mg per 100 g.

    Reference

    U.S. Standards for Grades of Processed Raisins, USDA Food Safety and Quality Service, Fruit and Vegetable Quality Division, Processed Products Branch, Washington, DC, 1978.


     


    N. Method for Processed Strawberries (V-78)

    (1) Scope

    This method covers procedures for processed whole or sliced strawberries to determine the percent of strawberries which contain rot due to decomposition by molds and to determine the numbers of insects present in representative samples.

    Most modern strawberries belong to the species Fragaria X ananassa Duch., which originated through hybridization of F. virginiana (Duch.) of Eastern North America and F. chiloensis (L.) Duch. of Western North and South America. Other species have also given rise to cultivated varieties. The frozen strawberry industry accounts for most processed strawberries, although some berries are still canned. Strawberries are also processed into preserves, jellies, ice cream flavor bases, fountain syrups, and pie fillings. This method is applicable to whole or sliced strawberries present as such in the latter products.

    (2) Applicable Documents

    1. CPG 7110.30 Defect Action Levels for Strawberries

    (3) Defects

    Strawberries are very susceptible to rot, especially in hot, humid, or rainy weather. Bruises acquired during picking and handling provide favorable sites for the establishment of mold growth. Sand, grit, and insects can contaminate frozen strawberries. Field insects injurious to strawberry plants mainly infest the roots, leaves, and buds. One example is the strawberry bud weevil (Anthonomus signatus Say). Proper plant sanitation practices during processing should control any other insect problems.

    (4) Procedure: Determination of Rot in Frozen Strawberries

    1. Sample Preparation -- Each subsample drawn from a barrel, a 30 lb can, or other large container, should consist of approximately 4 quarts of berries. Thaw each subsample and mix without damaging berries to make one composite subsample. If the berries are packed in consumer-size packages (10-16 oz.), use four such packages from the same code to make one composite subsample. Divide each composite subsample into 2 approximately equal portions, including juice, without damaging berries.
    2. Macroscopic Separation -- If the composite subsample consists of whole strawberries, use the entire first portion. If it consists of sliced strawberries, use about half of the first portion.

      1. (i) Visual Examination -- Drain the composite subsample on a No. 8 sieve. Transfer drained berries to a large white pan and cover with tap water. Decant most of the water through the sieve, catching and returning to the pan any strawberry tissue on the sieve. Repeat washing until water is fairly clear. Examine berries under water and remove all questionable berries to another pan containing deaerated water.
      2. (ii) Classification of Reject Strawberry Material -- Reexamine the questionable strawberry material removed from first pan and classify each strawberry, slice or fragment according to the following categories:

        • Rot areas 6-12 mm in diameter
        • Rot areas over 12 mm in diameter
        • Totally rotten strawberry material

        Confirm the presence of decomposed tissue in the questionable berries, as necessary, by examining sections of the berry tissue for mold, using the compound microscope. Strawberry material with rot areas less than 6 mm (minor defects) or unconfirmed as to presence of mold should be returned to the first pan containing berries with no apparent defects.

      Drain the berries with no apparent defects or minor defects on a tared No. 8 sieve for 2 min and weigh. Similarly drain and weigh strawberry material in each of the three reject categories.

    3. Microscopic Mold Count -- If a mold count of the unseparated composite subsample is required, use the second portion prepared according to (4)a. above and make mold count as in AOAC 952.22. If a mold count of the reject strawberry material prepared in (4)b. (i) or (ii) is desired to evaluate pick-out, prepare pulp as in AOAC 952.22. Mix 50 g pulped material with 50 g stabilizer solution (III. (15)) and make mold count of the mixed preparation.
    4. Report -- Tabulate results as follows:
      Code No. ______Subsample No.
      123etc.Average
      Total wt of drained fruit (g)     
      Total rotten fruit (g)
      Wt
      Percent
           
      Wt of fruit with rot areas
      6-12 mm in diameter
           
      Wt of fruit with rot areas
      over 12 mm in diameter
           
      Wt of totally rotten fruit     
      Percent of mold count     

      Remarks:


       

           

    (5) Procedure: Determination of Insect Contamination in Strawberries

    Weigh each subsample, thaw if frozen, then drain on No. 8 sieve nested in a No. 140 sieve. Wash berries thoroughly in cold water and transfer to a large white pan. Slice each berry longitudinally and examine for larvae, using magnification, if necessary. Transfer residue on the No. 140 sieve to the pan and examine for larvae. Report the numbers, size, and identity of larvae found in each subsample.

    Reference

    Strawberry Diseases, USDA Bulletin 2140.