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1 QUALITY EVALUATION AND CONTROL 3202 Luke Howard Professor Food Science Department University of Arkansas.

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1 1 QUALITY EVALUATION AND CONTROL 3202 Luke Howard Professor Food Science Department University of Arkansas

2 2 INTRODUCTION This module represents a brief overview of the course FDSC 4203; Quality Evaluation and Control taught by Dr Luke Howard at the University of Arkansas. It is narrated by Dr Steve Seideman, Extension Food Processing Specialist of the Institute of Food Science & Engineering, University of Arkansas.

3 3 INTRODUCTION The module will cover quality assurance, plant sanitation, GMPs, cleaning and disinfection methods, quality factors and standards, flavor and color determination, food additives and HACCP

4 4 Quality Assurance in the Food Industry (Portions of this section are from the book entitled Total Quality Assurance for the Food Industries by Dr Wilbur Gould and Ronald Gould. CTI Publications,Inc)

5 5 Quality Assurance Modern term used for describing the control, evaluation and audit of a food processing system Its primary function is to provide confidence for management and the ultimate customer (consumer) The customer establishes the level of quality the firm must manufacture

6 6 Canning & Quality Assurance

7 7 Quality Control A large part of a QA program is built around quality control Quality control means to regulate to some standard It is an important tool for the production worker to help operate the line in conformance with the predetermined parameters for any given quality level

8 8 Quality Evaluation Is also part of a QA operation It is used to describe or appraise the worth of a product It generally involves taking a measurement of the product in a laboratory It includes the evaluation of all incoming materials, products in process, and/or finished products

9 9 Quality Audit or Verification Goal is to audit or verify the products or processes over time Used for firms having many plants Part of the QA program to verify products in the warehouse, in distribution, and/or competitors products in the market place

10 10 Quality Makes a product what it is, varies among consumers Is the combination of attributes or characteristics of a product that have significance in determining the degree of acceptability of the product to a user Repeat sales are related to QA practices

11 11 Standards for Quality Legal standards Company or voluntary label standards Industry standards Consumer or grade standards

12 12 Subjective Methods for Determining Quality Based on the opinion of the investigators Usually involves sensory perception i.e. flavor, color, odor, touch, freedom from defects etc. Requires training and experience

13 13 Objective Methods for Determining Quality Physical - size, texture, color, consistency, imperfections, headspace, drained weight, vacuum Chemical - enzyme conc., moisture, fiber, pH, acidity Microscopic - used for adulteration and contamination, and differentiation between cell types, tissue types and microorganisms

14 14 QA Program Functions (1) Raw materials specifications for QC Improvement of product quality Improvement of processing methods with resulting savings in cost of production and > profits

15 15 QA Program Functions (2) Standardization of the finished product according to label specifications Increased order and better housekeeping of a sanitary plant Greater consumer confidence (uniform high quality)

16 16 Basic Fundamentals for a Successful QA Program Organization of the QA department The personnel Sampling Standards and specifications Measurement A. laboratory C. procedures B. equipmentD. reports Interpretation (SQC and SPC)

17 17 Examples of QE Functions (1) Determination of % germination and purity of seed Soil and tissue analysis Collection and summarization of weather data for use in scheduling of raw products, packaging materials, or labor Identification of crop diseases and insects

18 18 Examples of QE Functions (2) Determination of raw product quality and other in-coming raw materials Evaluation and continuous monitoring of processing variables affecting quality Determination of the efficiency of each processing operation as related to finished product quality

19 19 Examples of QE Functions (3) Periodic and continuous monitoring of water supply, equipment, plant sanitation, and the waste disposal system Evaluation of the finished product quality and assurance of the storage life of the finished product Development of new products and improvement of present processing, production and quality evaluation methods

20 20 Basic Equipment for QE Can opener Vacuum gauge Headspace gauge Grading scale, screens and trays Sizing gauges Brine and syrup cylinders Hydrometers and salometers Thermometers

21 21 Specialized Equipment for QE Colorimeter pH meter Refractometer Viscometer Moisture analyzer Microscope

22 22 Factors Affecting Quality Cultivar Maturity Cultural practices Harvesting and handling Processing Shelf-life Use

23 23 Food Plant Sanitation

24 24 Plant Sanitation Industries Responsibility Moral and legal obligation to perform all operations in clean surroundings, and with due regard to the basic principles of sanitation FDC Section 402a4 states that a food shall be deemed to be adulterated if it has become contaminated with filth, or whereby it may have been rendered injurious to health Sanitation is every persons job in the plant

25 25 Reasons for Plant Sanitation A better product, competition demands high, consistent quality A more efficient operation, efficiency equates to planned sanitation Greater employee productivity Improved safety Is a barometer of overall plant conditions

26 26 Plantkeeping - Exterior Grounds maintained Storage for equipment. Exterior openings screened Free from insects, rodent proof No uncovered openings No chemical spills Remove broken containers from shipping, receiving No trash in parking lot Paved roads No litter or waste accumulation Roofs leak proof

27 27 Plantkeeping - Building Floors water tight, smooth surfaced, and sloped 1/8 to 1/4 per foot to floor drains every 10 apart Drains covered with grates Walls doors, partitions, pipes, ceilings kept cleaned and painted Proper ventilation to prevent condensation, mold growth, or deterioration of structures All windows, doors and openings should be screened Good lighting, ranges from 25 to 150 foot candles

28 28 Plantkeeping - Equipment Constructed in regard to cleanability and protection from contamination Materials should be smooth, hard, non- porous, preferably stainless steel Pipe lines, fittings handling food should be sanitary Eliminate sharp corners Equipment should be directly accessible for cleaning (CIP) All open equipment should be covered Containers should be clean, and not used for other purposes (tight lids) Waste should be collected in proper containers (removed daily)

29 29 Plantkeeping - Storage Aisles should be kept clean and well marked Food materials, packaging should be protected from damage, rodents, insects, dirt, dust Stored products should be stored away from walls at proper storage temperatures Storage areas cleaned weekly Inventory and evaluation of warehouse products should be conducted frequently Storage temperature is critical for perishable ingredients/products Policy of FIFO should be strictly adhered to

30 30 Plantkeeping - Employees Must wear caps, hair nets, hair restraints Pins, curlers, jewelry, fingernail polish should not be worn Pens, pencils, watches should not be worn above the waistline Protective clothing worn at all times Gum chewing and tobacco use restricted to confined areas Glass bottles not permitted in working areas Employees must report any skin breaks to supervisors Observe proper habits of cleanliness

31 31 Plantkeeping - Employees Hands shall be washed and sanitized at the following times: A. When reporting to work B. After breaks C. After smoking or eating D. After picking up objects from the floor E. After blowing nose F. After coughing, sneezing and covering mouth with hand G. After using the toilet Signs should be posted throughout the facility as to smoking, eating and washing habits, and general sanitary requirements

32 32 Plantkeeping - Special Areas Special storage areas should be provided for handling of clean uniforms, towels, toilet articles, soiled uniforms and linens, custodians supplies and equipment, pesticides, employees belongings, and garbage and wastes Restroom facilities should include liquid soap, drying towels Restrooms should not open to processing areas Toilet facilities should be scrupulously clean Lunchroom facilities should be provided and kept clean

33 33 Plantkeeping - Materials In-coming materials should be carefully inspected and inventoried Outgoing materials should be properly identified in terms of shipments and quality Great losses occur in warehouses by improper housekeeping practices i.e. breakage, pilferage, looting etc.

34 34 Plantkeeping - Sanitary Organization The authority to uphold standards of sanitation is the responsibility of the plant sanitarian (in small plants might be the QA director or plant supervisor) Sanitarian should be well trained in microbiology, chemistry, entomology, parasitology, and sanitary engineering Sanitarian should be directly responsible to management

35 35 Plantkeeping - Sanitary Organization Required tools for sanitarians Ample supply of potable water Different types of brushes Detergents and knowledge of their use Chlorination and chlorinating equipment Steam and/or high pressure equipment fitted with proper nozzles

36 36 Plantkeeping - Sanitary Organization Flashlights for inspection of out of way places Black light for detection of rodents Camera Attire consisting of white cap, clean white overalls, or white shirt and pants Is responsible for training courses, workshops, seminars on sanitation and GMPs

37 37 Plant Inspection Plant inspection may be conducted by company personnel from either the home office, or the local plant, or by a third party A written report should be made in all observed conditions listed as satisfactory, needs improvement or unsatisfactory A manual should be written documenting minimum standards for each of the plant areas Report should be acted on accordingly

38 38 Sanitation Evaluation Physical cleanliness - absence of visual product waste, foreign matter, slime etc. Chemical cleanliness - freedom from undesirable chemicals i.e. cleaning compounds, germicides, pesticides, which might be present on the product or equipment Microbiological cleanliness - controlled by the amount of microorganisms that may be present in the product, or on the equipment, building or people

39 39 Suppliers Chemical supplier can assist in plant audit for developing a sanitation program Supplier can outline specific cleaning methods, products, and exact amounts, times and temps Labor amounts to 90% of a cleaning program Supplier can provide control and feeding equipment, engineering services, technical assistance, laboratory services, and sound planning for future needs

40 40 Sanitation Program Plant sanitation committee should meet monthly Sanitation committee may consist of: plant manager, production supervisor, QA supervisor, food technologist, maintenance engineer, personnel supervisor and sanitarian Training and retraining is critical Break down each job into components to instruct, try to get people to think about what they are doing, stress important repetitive situations

41 41 Cleaning and Disinfection Methods Portions of this section were taken from an article entitles : Sanitation; The Key to Food Safety and Public Health by James H. Giese. Food Technology. December 1991.

42 42 Challenges for Food Sanitation Increasing number of older consumers (immuno-compromised individuals) New products and processes (egs MAP, sous vide, aseptically packaged foods high pressure, pulsed electric fields) Sanitation programs are a prerequisite for HACCP programs

43 43 Plant Design Layout and functioning of the processing line should facilitate the flow of food material from one operation to the next with a minimum of delay Walls, floors and ceilings should be made of impervious, easily cleaned, non-painted inert material Positive air pressure should be maintained

44 44 Plant Design Raw materials should be isolated from processed food Adequate hand-washing stations should be provided in food processing areas Horizontal structures such as pipe hangers, beams, and duct work over exposed product areas should be eliminated

45 45 Plant Design

46 46 Plant Design

47 47 Sanitation: A Four Step Process A pre-rinse with high pressure water to remove gross soil Physical removal of soil by detergents and mechanical aids Another rinse to remove the detergent and loose soil The application of sanitizers to prevent recontamination before processing

48 48 Water Functions and Quality Carrier for detergents and sanitizers Carries soils or contaminants away from the surface that has been cleaned and sanitized Water hardness is responsible for excessive soap and detergent consumption, mineral deposits, undesirable films, and precipitates

49 49 Rinsing Step

50 50 Efficacy of Detergents Should wet and penetrate soil Should emulsify fat Should disperse and suspend soil Should counteract water hardness Should rinse well to prevent soil from redepositing on clean surfaces and be non-corrosive to equipment

51 51 Alkaline Detergents Compounds used for removal of organic soils, such as oils, grease, proteins and carbohydrates Strongly alkaline compounds (pH > 13) egs NaOH Moderately alkaline compounds (pH 10-12) egs sodium metasilicate Mildly alkaline compounds (pH 7-12) egs sodium carbonate and sodium sesquicarbonate Complex phosphates egs TPP, SHMP

52 52 Acid Detergents Compounds for removal of encrusted soils and deposits formed from application of alkaline detergents Strong inorganic acids egs hydrofluride, hydrochloride (scale removal in boilers, are corrosive to stainless steel) Organic acids egs citric and hydroxyacetic acids (used in manual cleaning formulations, also function as water softeners)

53 53 Detergent Auxiliaries Incorporated with cleaning compounds to improve their performance, provide filler material or bulk, condition water and protect sensitive surfaces Surfactants are organic compounds used in both alkaline and acidic formulations to increase soil penetration, improve rinsing, or to control foaming Sequestrants combine with magnesuim and calcium salts egs SPP, EDTA, sodium gluconate

54 54 Sanitizers Soil should be completely removed prior to sanitizing You cant sanitize a dirty surface Efficacy is affected by; time, pH, temperature, concentration, water hardness and surface cleanliness Chambers test requires that sanitizers produce a % kill of million E. coli and Staphylococcus aureus within 30 sec. After application at 20 o C

55 55 Regulation of Sanitizers and Cleaners FDA approves components of sanitizers by their chemical names, and determines a maximum use concentration on product contact surfaces EPA requires specific label information regarding usage and application requirements USDA authorizes cleaning and sanitizing compounds for use in federally inspected meat poultry, and egg processing plants

56 56 Important Properties of Sanitizers Ability to provide a rapid antimicrobial activity against a range of organisms Be readily available, inexpensive and ready to use Have stability and resistance to the presence of organic matter, detergent and soap residues Ability to work in a wide range of pH, water hardness, and temperatures Lack of toxicity to humans, and non-corrosive, and water soluble

57 57 Halogens Chlorine compounds - most popular and commonly used sanitizers Hypochlorous acid (HOCL) is the active killing agent, is strongly affected by pH (opt ) Kills bacteria by reacting with and disrupting cell walls Sodium hypochlorite is the most common form, but calcium hypochlorite, and Cl - gas are also used

58 58 Chlorine Reaction in Water Cl 2 + H 2 O HOCL + H + + Cl - NaOCL + H 2 O HOCL + Na + + OH - NH 2 CL + H 2 O HOCL + NH 2 + OH - HOCL H + + OCL -

59 59 Chlorine Dioxide Widely used in water and sewage treatment, becoming more popular with food processors Has 2.5 times the oxidizing power of chlorine Can be used at much lower concentrations Less sensitive to pH Must be generated on-site

60 60 Iodine Compounds Free elemental iodine and hypoiodous acid are frequently used antimicrobial compounds Alcohol-iodine solutions and iodophors are also commonly used Iodophors are aqueous solutions of a nonionic surfactant and complexed elemental iodine Iodophors are used for sanitizing utensils, equipment and as skin antiseptics Narrow pH range ( )

61 61 Quaternary Ammonium Compounds Quats are cationic surfactants used on floors, walls, and aluminum equipment An excellent application is on equipment in storage or when contact time will exceed 24hr Effective over a wide pH range (6-10), and at high temperatures, noncorrosive to metals, and unaffected by high levels of organic matter Effective against molds and gram negative slime formers

62 62 Acid-Anionic Sanitizers Commonly used in automated cleaning systems, which combine sanitizing with a final rinse Phosphoric acid is the most common form, with maximum antimicrobial activity below pH 3 Particularly suited for stainless steel, they can be used to help prevent mineral deposits by neutralizing excessive alkalinity They have rapid activity against most microorganisms, a low corrosive effect, resistance to organic matter and hard water salts

63 63 Hot Water and Steam Antimicrobial activity depends on the temperature, humidity and exposure time Hot water is convenient and cost effective, and is commonly used for sanitizing food contact surfaces, small equipment parts, utensils, and heat exchangers Steam is sometimes used to sanitize conveyor belts or other equipment in-place

64 64 Equipment and Systems Manual Aids Brushes should have a block constructed of durable material resistant to heat, chemicals and moisture Bristles should be nylon, with good water holding capacity to carry cleaning solution to contact surfaces Scrapers and scouring pads should be used to remove baked-on deposits and encrusted soil from equipment and other surfaces

65 65 High Pressure Systems Utilize high pressure hot water to remove soil Provides a very effective cutting action to remove gross soil build-up from equipment It is best utilized to clean hard-to-reach areas, conveyor systems, and outside surfaces of equipment, walls and floors Provide a good way to reduce manual labor costs

66 66 Foam Cleaning Systems These systems mix a metered amount of air and detergent solution to form a clinging foam Can be applied to areas that are inaccessible for hand cleaning Major difference between high pressure and foam cleaning are the application of foam at a lower PSI and its longer contact time Longer contact time allows soil to loosen and then removed

67 67 Foam Cleaning System

68 68 Clean-Out-of-Place (COP) Requires disassembly of equipment after rinsing so that parts and short pipe sections may be placed in a recirculation tank for cleaning by physical and chemical action Normal length of time for wash solution recirculation is ca min with an additional 5-10 min for a cold acid or sanitizing rinse Typically used for filling machine parts, centrifuge parts, pump heads and parts, pipe sections, take down fittings, homogenizer parts

69 69 Clean-In-Place (CIP) Systems Becoming popular due to labor savings and automated control (milk plants, aseptic systems) One shot systems have one tank for circulating the wash water and then discharging at the end of the rinse cycle Two tank systems consist of one tank for rinse water and another tank for reclaiming the cleaning solution, while three tank systems contain one tank for cleaning solution, one for reclaiming pre-rinse solution, and one for a final water rinse

70 70 Clean-In-Place System

71 71 Sanitizer Application Equipment Portable pressure sprayers Centralized systems can provide consistent sanitizer concentration and convenient hookups

72 72 Factors Affecting Sanitizer Efficacy Initial microbial load on raw product Water quality, chemistry and temperature Biofilm formation Concentration, temperature and contact time of sanitizer Organic matter content on the product and in the water

73 73 Quality Factors and Standards

74 74 Appearance Factors Size and Shape Can be easily evaluated and are important factors in federal and state grade standards Performed manually or by automated separating and grading equipment Eggs pass through different sized openings, and rollers, separation by weight after manual grading Curvature of cucumbers for pickling

75 75 Size and Color Sorting

76 76 Sorting

77 77 Weigh Grading

78 78 Color Sorting

79 79 Color Sorting

80 80 Appearance Factors Color and Gloss Indicates degree of ripeness of fruits/vegetables Quality of fried potatoes Bleaching of dried tomato powders Surface color of chocolate indicates storage history Color of a food foam or batter varies with the density and can indicate a change in mixing efficiency

81 81 Food Color

82 82 Color Measurement

83 83 Appearance Factors Color Measurement Color of transparent liquids such as beer, wine, grape juice are measured using spectrophotometers and colorimeters Color of liquid or solid foods are measured by comparing the reflected color to defined colored tiles or chips Color of many foods is measured using colorimeters, define the hue, chroma, and brightness of reflected light from food surfaces

84 84 Colorimeters

85 85 Hunter Color Solid

86 86 Color Wheel

87 87 Appearance Factors Gloss Measurement Light measuring instruments are available that measure the shine, or gloss of a food surface Gloss is important to the attractiveness of gelatin deserts and buttered vegetables

88 88 Gloss Meter

89 89 Appearance Factors Consistency Textural as well as appearance factor Consistency of foods is measured bt their viscosity, higher viscosity products being of higher consistency and lower viscosity being lower consistency Measuring devices include, consistometers (Bostwick), and viscometers (Brookfield, Cannon-Finske) Used for ketchup, honey, syrups, purees

90 90 Viscometers

91 91 Viscometers On-Line

92 92 Viscometers

93 93 Rheological Properties

94 94 On-Line NIR for Chemical Analysis

95 95 Textural Factors Texture refers to those qualities of food that we can feel either with the fingers, the tongue, the palate, or the teeth Texture is an important quality attribute for many foods including; chewing gum, crackers, chips, fruits, bread products, meats etc.

96 96 Measuring Texture Measurements of resistance to force Many different types of instruments are available to measure different types of force (e.g.succulometers, penetrometers, consistometers, tenderometers). Force-distance curves give important information about the rheological properties of foods

97 97 Texture Changes in Foods Water content plays a major role (e.g. firmness of fruits and vegetables, bread staling, freezer burn etc ). Food composition is also important Lipid, starch, protein, and sugar content affects functional properties of foods Many food ingredients may affect textural properties

98 98 Texture Analyzers

99 99 Texture Analyzers

100 100 Texture Profile Analysis

101 101 Texture Profile Analysis

102 102 Flavor Factors Flavor is a combination of taste and smell, is largely subjective and thus, difficult to measure Flavor is affected by the basic taste attributes (sweet, sour, bitter, salty), and numerous volatile compounds which affect aroma Flavor is measured using analytical instrumentation and sensory tests A goal of many QC groups is to identify chemical measurements that may be used to predict sensory quality

103 103 Odor Determination

104 104 Electronic Nose for QC

105 105 Sensory Panels Consumer preference groups - untrained panels that can provide a good insight into what consumers generally will prefer Trained panels - are selected on the basis of their flavor sensitivity and trained to recognize attributes and defects of a particular product Triangle and preference tests are commonly used for QC functions

106 106 Sensory Analysis

107 107 Additional Quality Factors Nutritional quality - assessed by chemical or instrumental analyses Sanitary quality - measured by counts of bacteria, mold, yeast, insect fragments, also rocks, stones, glass fragments, metals are identified using x-ray machines and metal detectors Keeping quality - shelf life studies, ASLT

108 108 Quality Standards Research - internal standards set up by a company to help ensure the excellence of its products Trade - standards set up by members of industry on a voluntary basis to assure at least minimum acceptable quality Federal grade standards - have been set up mainly to help producers, dealers, wholesalers, retailers and consumers in marketing food products, provide a common language for trading

109 109 Federal Grade Standards Standards of quality administered by the USDA Marketing Service and the FSIS Grading - is voluntary and is used to determine the quality of products such as meats Inspection - is mandatory and assures the wholesomeness of products Uniform grades of quality established for > 100 foods (meat, dairy, poultry, fruits, vegetables, seafood)

110 110 Federal Grade Standards Meats Age of the animal Amount and distribution of muscle fat (marbling) Firmness and texture of the flesh Color of the lean meat Federal grade marks for beef are; Prime, Choice, Select, Standard, Commercial, Utility, Cutter, Canner

111 111 USDA Standards of Composition and Identity Minimum content requirements for federally inspected meat and poultry products (canned or frozen) For example, the USDA minimum requirement for beef stew specifies the minimum percentage of beef only (25%), that the stew must contain Complete standards of identity have been established for chopped ham, corned beef hash, and oleomargarine

112 112 FDA Standards of Identity Establishes what a given food product is Example - what a food must contain to be labeled preserves Includes both mandatory ingredients and optional ingredients

113 113 Minimum Standards of Quality Have been established for many canned fruits and vegetables to supplement standards of identity Examples include; tenderness, color and freedom from defects If a food does not meet the FDA quality standards it must be labeled below standard in quality

114 114

115 115 Flavor Determination

116 116 Food Flavor Involves at least two phenomena, taste and odor When we say a food tastes good, we actually mean it has a good taste and aroma Taste: is the subjective experience (sensation) resulting from stimulation of the chemosensory receptors (taste buds) located on the oral cavity by chemicals or chemical components of food in solution with saliva

117 117 Basic Taste Attributes Salty Sweet Sour Bitter

118 118 Taste Strictly tongue taste, not flavor Taste originates from compounds in solution (saliva) All taste buds can detect all four qualities, but some respond to one quality better than the other three

119 119 Salty Quality Is the result of ionic stimulation Na + is responsible for eliciting salty taste, while anions especially Cl - are inhibitory Many inorganic salts in solution taste differently depending on molecular concentration eg. at low concentration many salts taste sweet, with increasing concentration the taste may be salty, sour or bitter

120 120 Sour Quality Chemical stimulus is the hydrogen (H + ) ion The threshold number of hydrogen ions necessary for perception of a sour taste is smaller for weak acids than for strong acids Indicates that the anion or undissociated acid may modify the taste of these compounds

121 121 Sweet Quality Is elicited by a variety of food related organic compounds Most common sweetners are sugars, which vary considerably in sweetness Based upon equimolar solutions fructose > sucrose > maltose > glucose > lactose Sweetness is affected by concentration, food medium, and temperature of food medium

122 122 Bitter Quality Is difficult to associate with a specific stimulus Most prominent class of bitter tasting compounds are the alkaloids (caffeine, quinine and nicotine) Other include heavy halide salts, amino acids and phenolics

123 123 Typical Thresholds for Taste Attributes Sweet (sucrose)0.250% ppm Bitter (caffeine)0.016% ppm Sour (citric acid)0.200% ppm Salty (NaCl)1.500% - 15,000 ppm

124 124 Food Smell or Odor Refers to sensations resulting from stimulation of the chemosensory receptors located in the olfactory epithelium of the nose by airborne chemical compounds Chemicals may reach the epithelium directly through the nares, or indirectly (rostronasally), through food present in the mouth

125 125 Food Smell or Aroma

126 126 Color Determination

127 127 Color Consumers typically select a food based upon it appearance and color Color can be measured more easily than taste, odor or texture Color is one portion of the input signals to the human brain that results in the perception of appearance

128 128 Color Color as seen by the human eye is an interpretation by the brain of the character of light coming from an object We need to define color in a physical sense as objectively as possible and interpret the output in terms of how the human eye sees color

129 129 Color Defined as: the aspect of radiant energy of which a human observer is aware through the visual sensations which arise from the stimulation of the retina of the eye Color is a characteristic of light, that is measurable in terms of intensity and wavelength It arises from the presence of light in greater intensities at some wavelengths than at others

130 130 Fates of Light When Illuminated Reflected Transmitted Absorbed Refracted

131 131 Color Perception If all light is reflected from an opaque surface, the object appears white Is some light is absorbed, the object appears gray If all light is absorbed, the object appears black

132 132 Color Perception The perception of color results from differences in absorption of radiant energy at various wavelengths Maximum reflection in the short wavelength range ( nm) results in blue Maximum reflection in the medium wavelength range ( nm) results in green or yellow Maximum reflection in the long wavelength range ( nm) results in red

133 133 Colors in the Visible Spectrum

134 134 Physiological Basis of Color The human eye has two types of sensitive cells in the retina A. Rods - are sensitive to lightness & darkness B. Cones - are sensitive to color a. one set is sensitive to red light b. one set is sensitive to green light c. one set is sensitive to blue light

135 135 Physiological Basis of Color Cones send a signal to the brain that sets up a response in terms of opposing pairs A. One pair is red-green B. One pair is yellow-blue This is why some individuals are red- green, or blue-yellow color blind

136 136 Color Measurement Munsell System Contains 1225 color chips used for convenient visual comparison Each chip has a numerical designation Advantages: simple, convenient, easy to understand Examples: color grades for tomato juice, glass color standards for sugar products, plastic color standards for peas, lima beans, apple butter, peanut butter, canned peaches, mushrooms

137 137 Color Measurement Munsell System Disadvantages Plastic and glass standards are available in a limited number of colors Painted paper chips come in an array of colors, but are fragile, and fade with time Repeated visual judgements are tiring and tedious Color that fall between existing standards are difficult to communicate to other individuals

138 138 Spectrophotometric Measurement of Color Early instrumental methods for color measurement were based on transmission, or reflection spectroscopy Researchers developed the response of the cones in the eye in terms of the visible spectrum X (red), Y (green) and Z (blue) were used as reference stimuli

139 139 Spectrophotometric Measurement of Color If we take the red, green, and blue data for the spectral colors, transform them to X, Y, and Z coordinates, and plot the response of the human cones against wavelength, we get the response of the human eye to color These curves were standardized in 1932 and called the CIE (International Commission of Illumination) x, y, z standard observer curves

140 140 Spectrophotometric Measurement of Color Having the data in the standard observer curves, it is mathematically simple to calculate color from a reflectance or transmission spectrum The sample spectrum is multiplied by the spectrum of light source and the area under the resultant curve is integrated in terms of the x, y, z curves The resulting figures for X,Y, Z specify the color of the sample

141 141

142 142 Food Additives

143 143 History of Food Additives Smoking and sun drying were early methods used for food preservation Much of our history is an indirect result of mans quest for spices and other flavorings egs Marco Polos travels, discovery of America by Columbus, Cortez and the vanilla bean Texas settlers in the 1800s - chili powder

144 144 Food Additives A substance or mixture of substances, other than a basic foodstuff, which is present in a food as a result of any aspect of production, processing, storage or packaging

145 145 Food Additive Categories Intentional additives - Those which are added to perform a specific function. They are measured and added in scientifically controlled amounts; therefore the amounts added are generally small. Incidental additives - Substances present in foods in trace quantities as a result of some phase of production, processing, storage or packaging. These are unavoidable from a practical viewpoint.

146 146 Reasons for Using Food Additives Rapidly expanding population, and migration of the population from rural to urban areas With < 5% of the population growing food for the remaining 95%, much of the food would never reach consumers in edible condition without additives Additives help the food supply to be palatable, convenient, nutritious, safe, with a long shelf-life and pleasing flavor

147 147 Food Preservative Categories 1). Those which act to control or prevent growth of microbes Salts or various acids such as proprionic, sorbic and benzoic Calcium proprionate - mold inhibitor in bread Potassium sorbate - mold inhibitor in cheeses, syrups, jams, mayonnaise and pickles Sodium benzoate - mold inhibitor in high acid foods, fruit drinks, carbonated beverages

148 148 Food Preservative Categories Nitrates - prevent the growth of Clostridium botulinum in cured meats, also fixes the color and enhances the flavor of these products It is possible that nitrites combine with amines in the stomach to form nitrosamines These compounds are under investigation as possible carcinogens

149 149 Food Preservative Categories 2) Preservatives which act by inhibiting detrimental chemical changes Prevention of rancidity in fatty foods can be accomplished with BHA, BHT, propyl gallate Citric acid, phosphoric acid and ascorbic acid are often added to enhance the effectiveness of BHA and BHT

150 150 Food Preservative Categories Chelating or sequestering agents (EDTA and SHMP) are added to foods to bind trace metals which can act as catalysts in food spoilage These agents are used to prevent or reduce discoloration, clouding and rancidity Used in products such as soft drinks, cream style corn, shrimp and beer

151 151 Flavoring Agents Sugar and salt are the most widely used additives Sugar not only contributes sweetness, but it also adds body to beverages, tenderness to baked goods, and color when caramelized Salt and sugar also may be used as preservatives at high concentrations

152 152 Flavoring Agents Non-nutritive sweetners such as saccharin and aspartame are commonly used MSG, combines with protein to enhance the flavor of high protein foods, but does not contribute a flavor of its own. Disodium inositate and disodium guanylate are also used as flavor enhancers in dry soup mixes

153 153 Coloring Agents Natural coloring agents include; annatto, carotenes, cochineal Annatto - commonly used in dairy products, margarine, cheese and ice cream Cochineal - added to meat products, spices and baked goods

154 154 Coloring Agents Synthetic agents include; FD&C yellow #5 and red #4 The soft drink industry is one of the prime color users

155 155 Stabilizers and Thickeners These compounds may be derived from natural plant extracts, chemically modified natural products, or may be completely synthetic products Stabilizers are added to chocolate milk to prevent chocolate particles from settling out, or added to ice cream to bind excess water, this preventing ice crystals and a grainy texture

156 156 Stabilizers and Thickeners Thickeners are added to icing, cheese spreads, salad dressings, pie fillings, soups and gravies to provide the desired consistency Additives such as sodium alginate, cellulose gums and pectins are used to provide body to sugar-sweetened soft drinks

157 157 Emulsifiers and Surface Active Agents Emulsifiers permit the dispersion of tiny particles or globules of one liquid in another An oil and vinegar salad dressing illustrates one important use of emulsifiers Emulsifiers such as mono-glycerides play an important role in the baking industry by helping to increase volume, uniformity, fineness of grain and shelf life

158 158 Emulsifiers and Surface Active Agents Lecithin, one of the most widely used emulsifiers, is a natural substance found in both plant and animal tissues Surface active agents (surfactants) of which emulsifiers are one type are used to lubricate foods (reduce slipperiness) Applications include; prevention of stickiness in peanut butter and caramel products

159 159 Nutrition Supplements Fruit acids (citric, malic, acetic, tartaric) are used to intensify flavors in many food products including sherbets, cheese, grape and lime beverages, jams, jellies, candies and pickles Ammonium bicarbonate, sodium carbonate and calcium carbonate are examples of alkalies which are used to prevent a food product from becoming too acid Compounds are used to reduce the acidity of wines, control acidity of in canned peas and olives

160 160 Firming Agents Firming agents improve the texture of processed fruits and vegetables Calcium chloride, calcium lactate and aluminum sulfate (alum) are used to improve the texture of pickles, maraschino cherries, and canned peas, tomatoes, potatoes and apples

161 161 Anticaking Agents Anticaking agents are important in the salt industry where sodium silico aluminate is used to prevent particle clumping Calcium phosphate performs the same function in Tangtype drinks Corn starch is added to powdered sugar to keep it free-flowing Calcium stearate in garlic salt is another example of the use of anticaking agents

162 162 Leavening Agents A leavening agent is any chemical or biological substance that can produce bubbles of gas in dough These gas bubbles expand, causing the dough to rise; thus yielding foods which are light in texture Yeast was originally used, but is not a reliable source of gas

163 163 Leavening Agents Baking powders have replaced yeast as the preferred leavening agents These powders are generally composed of sodium bicarbonate, an acid salt such as calcium monophosphate, and starch The phosphate and bicarbonate readily react in the presence of water to produce carbon dioxide The starch helps keep these ingredients dry and non-reactive, so that a given volume of baking powder will create a given amount of gas

164 164 Maturing and Bleaching Agents The bleaching process of milled flour is accelerated by the addition of certain chemicals such as chlorine or chlorine dioxide in the form of a gas These compounds make it possible to produce consistently high quality flour, and avoid the problems created by prolonged storage, with little loss of nutritive quality

165 165 Humectants These are substances such as propylene glycol, sorbitol, glycerine and mannitol which are added to foods to help keep them moist Proplyene glycol is added to shredded coconut and marshmallows, dried onions and garlic flavored croutons to perform this function Sorbitol helps maintain the smooth consistency of candies and fudges

166 166

167 167 HACCP Principles and Produce Operations

168 168 Produce Associated Foodborne Illness According to the Centers for Disease Control and Prevention, the number of produce-related outbreaks per year doubled between the periods and

169 169 HACCP Background HACCP system for food safety was first developed by food processors in cooperation with NASA in the 1960s to ensure the safety of space foods Food microbiology, risk assessment and QC principles were joined to form the HACCP system The low acid food industry utilized HACCP in the 1970s in cooperation with the FDA to ensure the quality of low acid canned foods

170 170 Hazard Analysis Critical Control Point (HACCP) Program Is a systematic approach to the identification, evaluation, and control of food safety hazards, from raw material production and procurement to distribution and consumption of the finished product (NAC-MCF, 1997)

171 171 The 5 Pre-HACCP Steps Bring together your HACCP resources Describe the product and its method of distribution Develop a complete list of ingredients and raw materials Develop a process flow diagram Meet the regulatory requirements for sanitation standard operating procedures

172 172 HACCP is Based on Seven Principles 1. Conduct a hazard analysis 2. Determine the critical control points 3. Establish critical limits 4. Establish monitoring procedures 5. Establish corrective actions 6. Establish verification procedures 7. Establish record-keeping and documentation procedures

173 173 Quality and Safety Begins in the Field

174 174 HACCP Principle #1 Assessment of hazards and risks associated with growing, harvesting, raw materials and ingredients, processing, manufacturing, distribution, and marketing, preparation and consumption of the food

175 175 Potential Hazards to be Monitored Microbiological: E. coli, coliforms, aerobic plate count, Salmonella, Listeria, foodborne viruses Chemical: pesticides, detergent cleaners, chlorine residue Physical: insects, wood, glass, sand, rocks, metal

176 176 HACCP Principle #2 Determine the critical control points (CCP) required to control the identified hazards All hazards identified by the hazard analysis must be controlled at some point

177 177 Examples of CCPs Raw product temperature Storage temperature Chlorination Sanitation Employee hygiene & GMP audits Foreign objects

178 178 Monitoring Water Chemistry

179 179 Gloves and Hand Washing

180 180 HACCP Principle #3 Establish the critical limits which must be met at each identified CCP Critical limits are tolerances established beyond which the related CCP is out of control and a potential hazard can exist

181 181 Examples of Critical Limits Storage temperature (32-40 o F for vegetables) Chlorine levels ( ppm) Sanitation procedures (frequency) Microbiological standards (zero salmonella) Residual chlorine (1 ppm)

182 182 HACCP Principle #4 Establish procedures to monitor CCP Procedure should be reliable enough to indicate that the hazard is under control Due to short shelf life of pre-cut produce, monitoring procedures should be performed quickly

183 183 Examples of Monitoring Procedures for CCPs Thermometer calibration GMP audits Sanitation swab testing

184 184 HACCP Principle #5 Establish corrective action to be taken when there is a deviation identified by monitoring of a CCP Corrective action must eliminate the hazard which has resulted by deviation from the HACCP plan and must demonstrate that the CCP has been brought under control

185 185 HACCP Principle#6 Establish effective recordkeeping systems that document the HACCP program The HACCP plan should be on file at the processing plant and it should include documentation relating to CCP and any action on critical deviations and disposition of product

186 186 Examples of Records in a HACCP Program Ingredients: supplier certification, audit records, storage time & temperature recorders Product safety: safe shelf life records, microbiological records, records relating to adequacy of processing procedures Processing: records of all monitored packaging CCP, including seal quality and compliance with packaging material specifications

187 187 Examples of Records in a HACCP Program Storage and distribution: records on temperature/truck cleanliness Deviation file: records of any deviation to the HACCP plan Only those records pertaining to CCP must be available to regulatory agencies at their request

188 188 HACCP Principle #7 Establish procedures for verification that the HACCP system is working correctly Verification consists of methods, procedures and tests used to determine that the HACCP system is in compliance with the HACCP plan Verification confirms that all hazards in produce processing are identified in the HACCP plan

189 189 Examples of Verification Activities Periodic review of HACCP Review of HACCP records Review of deviations and dispositions Random sample collection and analysis

190 190 SUMMARY This module has briefly covered food quality assurance, plant sanitation, GMPs, cleaning and disinfection methods, quality factors and standards, flavor and color determination, food additives and HACCP.

191 191

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