<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>060400 - Disclosure - INVENTORY</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>1</Level><ElementName>us-gaap_InventoryDisclosureAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>INVENTORY [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_InventoryDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>verboseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="c20130101to20130630" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="font-family: 'Times New Roman', Times, serif; font-size: 10pt;"&gt;&lt;div style="font-size: 10pt; font-family: Times New Roman; font-weight: bold; text-align: left; margin-left: 0pt; text-decoration: underline; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;NOTE 4 &amp;#8211; INVENTORY&lt;/div&gt;&lt;div style="text-align: justify; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;&lt;/div&gt;&lt;div style="font-size: 10pt; font-family: Times New Roman; text-align: justify; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;At June 30, 2013 and December 31, 2012, inventory consists of the following:&lt;/div&gt;&lt;div style="text-align: justify; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;&lt;/div&gt;&lt;div&gt;&lt;table cellpadding="0" cellspacing="0" style="font-size: 10pt; font-family: times new roman; width: 100%;"&gt;&lt;tr&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 31%;"&gt;&amp;#160; &lt;/td&gt;&lt;td valign="top" style="border-bottom: black 2px solid; width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; font-weight: bold; text-align: center; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;6/30/13&lt;/div&gt;&lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 3%;"&gt;&amp;#160; &lt;/td&gt;&lt;td valign="top" style="border-bottom: black 2px solid; width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; font-weight: bold; text-align: center; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;12/31/12&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="#cceeff"&gt;&lt;td align="left" valign="top" style="width: 31%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: left; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;Raw materials&lt;/div&gt;&lt;/td&gt;&lt;td align="right" valign="top" style="width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;$176,678&lt;/div&gt;&lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 3%;"&gt;&amp;#160; &lt;/td&gt;&lt;td align="right" valign="top" style="width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;$42,831&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="white"&gt;&lt;td align="left" valign="top" style="width: 31%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: left; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;Packaging&lt;/div&gt;&lt;/td&gt;&lt;td align="right" valign="top" style="width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;11,338&lt;/div&gt;&lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 3%;"&gt;&amp;#160; &lt;/td&gt;&lt;td align="right" valign="top" style="width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;1,873&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="#cceeff"&gt;&lt;td align="left" valign="top" style="width: 31%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: left; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;Work-in-process&lt;/div&gt;&lt;/td&gt;&lt;td align="right" valign="top" style="width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;18,930&lt;/div&gt;&lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 3%;"&gt;&amp;#160; &lt;/td&gt;&lt;td align="right" valign="top" style="width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;64,170&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="white"&gt;&lt;td align="left" valign="top" style="width: 31%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: left; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;Finished goods&lt;/div&gt;&lt;/td&gt;&lt;td align="right" valign="top" style="width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;787,917&lt;/div&gt;&lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 3%;"&gt;&amp;#160; &lt;/td&gt;&lt;td align="right" valign="top" style="width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;360,428&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="#cceeff"&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 31%;"&gt;&amp;#160; &lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 13%;"&gt;&amp;#160; &lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 3%;"&gt;&amp;#160; &lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 13%;"&gt;&amp;#160; &lt;/td&gt;&lt;/tr&gt;&lt;tr bgcolor="white"&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 31%;"&gt;&amp;#160; &lt;/td&gt;&lt;td align="right" valign="top" style="border-bottom: black 4px double; width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;$994,863&lt;/div&gt;&lt;/td&gt;&lt;td valign="top" style="font-size: 10pt; font-family: times new roman; display: inline; width: 3%;"&gt;&amp;#160; &lt;/td&gt;&lt;td align="right" valign="top" style="border-bottom: black 4px double; width: 13%;"&gt;&lt;div style="font-size: 10pt; font-family: times new roman; text-align: right; margin-left: 0pt; display: block; margin-right: 0pt; text-indent: 0pt;"&gt;&amp;#160;$469,302&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for inventory. This may include, but is not limited to, the basis of stating inventory, the method of determining inventory cost, the major classes of inventory, and the nature of the cost elements included in inventory. If inventory is stated above cost, accrued net losses on firm purchase commitments for inventory and losses resulting from valuing inventory at the lower-of-cost-or-market may also be included. For LIFO inventory, may disclose the amount and basis for determining the excess of replacement or current cost over stated LIFO value and the effects of a LIFO quantities liquidation that impacts net income.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 210

 -SubTopic 10

 -Section 50

 -Paragraph 1

 -URI http://asc.fasb.org/extlink&amp;oid=6361739&amp;loc=d3e7789-107766



Reference 2: http://www.xbrl.org/2003/role/presentationRef

 -Publisher AICPA

 -Name Accounting Research Bulletin (ARB)

 -Number 43

 -Section A

 -Paragraph 9

 -Chapter 3

 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 3: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 210

 -SubTopic 10

 -Section S99

 -Paragraph 1

 -Subparagraph (SX 210.5-02.6)

 -URI http://asc.fasb.org/extlink&amp;oid=6877327&amp;loc=d3e13212-122682



Reference 4: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 02

 -Paragraph 6

 -Subparagraph a, b, c

 -Article 5



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