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Post harvest is the time that begins with separation of commodity from growing of production medium like fruits/ vegetables from the plants, f ishes from ponds etc. The term post harvest technology means the use of science and technology for the management of food commodities including pre-cooling, grading, sorting, packaging, transportation, storage, processing, and development of improved product, preservation and marketing etc. The use of the information generated by the techniques of Post Harvest Technology can ensure greater availability of a wide variety of food to the consumers with reduced post harvest losses. Based on the importance of the post harvest technology in agriculture and allied sciences, it is presumed that all people engaged in agriculture should know about the various terminologies being used in post harvest technology. But to understand the various concepts, some sort of documentation is needed. A manuscript having such information would be the strongest link between the industry, academia and the consumers. The students, teachers, and researchers often need a direct reference which is complete on the subject for teaching undergraduate or postgraduate students. So the authors made an attempt to meet out this need. The book entitled “Post Harvest Management and Technology: An Illustrative Guide” contains important glossary of all related terms of post harvest technology for all alphabets from A to Z. This book is covering almost every important terminology pertaining to post harvest technology including other interrelated disciplines like physiology, processing, food science, food technology, food engineering, food packaging, food biochemistry and applied nutrition, industrial microbiology, health foods, and quality management etc. The terminology in each alphabet has been well illustrated with examples and photographs for better understanding. At present, there is no book available which gives complete information related to Post Harvest Technology. The book will be highly beneficial to both UG and PG students undergoing courses in Postharvest Technology, entrance examination for PhD in Post Harvest Technology at IARI, various examinations pertaining to JRF and SRF as well as NET. We acknowledge from the core of our heart for the valuable guidance and support received from numerous publications of many committed and dedicated members of scientific community who have contributed tirelessly in the field of post harvest technology. Their assistance for the information obtained from literature and websites that were consulted during the preparation of the manuscript is thankfully acknowledged. Words are inadequate to express our gratitude towards our most venerable parents and family members whose constant inspiration and innumerable sacrifices have encouraged us to complete this goal. It is hoped that the book will be welcomed and its benefits will be availed by an increased number of food professionals like students, researchers, teachers and all those who have interest in the subject. Although, every care has been taken by the authors while writing this text book even then spelling mistakes, overlapping; repetition of brief portion here and there could not be helped. Needless to say, errors and omissions are solely our. Constructive criticisms and suggestion by the readers are welcome for improving the quality of manuscript. Reader’s indulgence in this regard is highly solicited.

Abnormal milk: It is milk that is not smooth and homogenous but is flaky, ropy, stringy, slimy, watery, discoloured or bad flavoured (Plate 1 & 2). Abrassive peeler: It is equipment comprising a rotating drum lined with carborandum (an abrasive material) in which certain vegetables like potato and ginger are tumbled and exposed to the abrasive action of the carborandum lining, thereby facilitating separation of peel from the vegetables (Plate 3). Absinthe: It is green liqueur which is flavored with wormwood, anise, and other aromatic herbs (Plate 4). Its commercial production is banned in ma ny countries for health concerns. Absolute alcohol: It is water free alcohol. It contains atleast 99 per cent pure alcohol by weight and obtained by digesting rectified spirit over quicklime and redistilling the same. Absolute density: It is the ratio of weight of certain volume of a substance at 1oC to that of weight of same volume of water at 4oC. Absolute humidity: Absolute humidity is defined as kg of water vapour per kg of dry air at a given temperature and pressure. Absolute humidity is the mass of water vapour divided by the mass of dry air in a certain volume of air at a specific temperature. The warmer air absorbs more water than cooler one. Absolute humidity is the measure of water vapour or moisture in the air, regardless of temperature. Absolute pressure: It is equal to atmospheric pressure minus vacuum pressure (Plate 5). Absolute zero: It is a theoretical temperature characterized by complete absence of heat and motion and equivalent to exactly -273.15°C or -459.67°F (Plate 6).

B.T.U.: It stands for British thermal unit. The heat required to raise the temperature of one pond of the water through 1oF is called BTU (Plate 82). Baby back ribs: Meaty pork ribs cut from the lower back rib section. Bacitracin: A polypeptide antibiotic isolated from a bacillus (Bacillus subtilis or B. licheniformis) and usually used against gram-positive bacteria. Back Bacon / Canadian bacon: Bacon cut from the loin that has little fat and is cut into round or oblong slices. Backward feed evaporator: In this evaporator, fresh feed enters the last and the coldest effect and continues on until the concentrated product leaves the first effect (Plate 83).

C - enamel can: The sulphur resistant lacquer is golden coloured and the can coated with it are called C-enamel can or sulphure resistant can, used for packing non acid products (Plate 143). CA storage: Storage of commodities under gaseous atmosphere like gas storage, where the composition of atmosphere is controlled accurately. MA and CA differ only in degree of control and CA is more exact. These storage methods in combination with refrigeration markedly enhance storage life of fruit and vegetables (Plate 144). CAC: It stands for Codex Alimentarious commission (1962). It is a joint commission of FAO and WHO, comprising of 146 member countries. It ensures consumer food safety, establish fair practices in food trade and promote the development of international food standards. CAC make standards for food additives, veterinary drugs, pesticide residue and other miscellaneous substances that affect consumer safety. These are published in Codex Alimentarius.

Dahi: It is the product obtained from pasteurized or boiled milk by souring, natural or by harmless lactic acid or other bacterial culture. It is also called Curd (Plate 209). Dairy: It is a room, building, or establishment where milk is kept and butter / cheese is made or it is the department of farming / farm that is concerned with the production of milk, butter, and cheese or an establishment for the sale / and distribution of milk and milk products. Dairy husbandry: It deals with care, breeding, feeding, milking of the diary cattle and the production and sale of the milk. It is the economical management of a dairy, including looking after the dairy cattle breeding and proper disposal or sale of milk and milk products. Dairy products: These are the milk preparation, including butter, cream, cheese, ghee, yoghurt, pasteurized milk, tonned milk, butter milk etc processed and prepared in dairy. Ice cream and kulfi or sweets are not included in this. Damage: Damage is a physical spoilage, often a partial deterioration, are subjectively judge and very difficult to measure and usually reported as per cent damage. Daminozide: It is a growth regulator which is used for red colour development in apple.

E numbers: Each food additive used in the food industry has been given a specific number code for their identification. These numbers are called as E numbers. These E numbers are used within the European Union. The word prefix “E” stands for Europe. They are commonly used on the food label through out the European Union. These are not used in Australia and New Zealand. The different food additives are given different E numbers depending upon the type of food additive like E100-E199 (food colours), E200-E299 (preservative), E300-E399 (antioxidants), E400-E499 (thickners, stabilizers, emulsifier), E500- E599 (pH regulator, anticaking agent), E600- E699 (flavour enhancers), E700-E799 (antibiotics), E900-E999 (miscellaneous like waxes, synthetic glazes, packaging gases, sweetners, foaming agents), and E1000-E1099 (additional chemicals). Earling: The young lamb of one to two years’ age is called earling or yearling. Ebullioscopic constant: The boiling point elevation is expressed by Dtb = Km, where m is molality of the solution and K is ebullioscopic constant. It is also called as molal boiling point elevation constant. The unit of an ebullioscopic constant is K Kg mol-1.

F0 value: It is used to express F-value when z =10oC / 18oF and the temperature is 121.1oC. It is the number of minutes at a specific temperature (250oC) required to destroy or kill a stated number of microorganisms and has specific z-value. It is also called reference value. Facing or lining board: The layer of the paper on which the flute is embedded is called facing or lining board (Plate 258). Facultative anaerobic: Organisms that grow either with or without oxygen. Facultative parasites: Facultative parasites can adapt to live on dead organic matter and often have a wide host range and can easily be cultured on artificial media. These organisms may be aerobic or anaerobic but under changed conditions, they changes to anaerobic or aerobic. Falling rate period: It is that part of the drying process during which the drying rate varies with time and the instantaneous drying rate per unit surface or weight of dry material continuously decreases. Falling rate takes place when most of the moisture has been evaporated during constant rate period. The falling rate period during dehydration take place in the final stage of dehydration when the food commodities have large amount of free water available for evaporation. Here, rate of removal of the moisture from the food to the surrounding is continuously decreasing / falling per unit time.

Galactometer: It is an instrument used for recording the specific gravity of the milk (Plate 306). Galactose: It is an aldohexose sugar obtained by hydrolysis of lactose. Galactose is a monosaccharide and has the same chemical formula as glucose, i.e., C6 H12 O6 . It is similar to glucose in its structure, differing only in the position of one hydroxyl group. Due to this difference galactose possess different biochemical properties to glucose (Plate 307). Galactosidase: An enzyme (actase) that hydrolyzes a galactoside. β-Galactosidase, commonly known as lactase, is an enzyme responsible to hydrolyze lactose (Plate 308). Galactoside: A glycoside that yields galactose on hydrolysis. A galactoside is a glycoside containing galactose. The H of the OH group on carbon-1 of galactose is replaced by an organic moiety (Plate 309). Galactosyl: A glycosyl radical C6 H11 O5 that is derived from galactose.

HACCP: The Hazard Analysis and Critical Control Points (HACCP) is a scientific, rational and systematic approach to identify, assess and control hazards during production, processing, manufacturing and use of food. It ensures safety of the food. HACCP presents a good opportunity for the food industry for upgrading quality and bringing uniformity and consistency in their supplies to international market. or It is a systematic preventive approach to food safety that addresses physical, chemical and biological hazards as a mean of prevention rather than finished product inspection. It involves identification, evaluation and control of hazards which are significant for food safety. HACCP plan: A document prepared in accordance with the principles of HACCP to ensure control of hazards which are significant for food safety throughout the food chain under consideration. Haemagglutinins: A group of proteins of plants that are not antibodies and do not originate in an immune system but bind specifically to carbohydrate containing receptors on cell surfaces (red blood cells). It is also known as Phytoagglutins / lectins.

Ice bank cooling: Storing of fruit and vegetable in storage chamber with positive ventilation and system countries where ice formation is allowed during night time (as electricity cost of night is less as compared to the day time). Melting of ice occurs during day time and with proper air circulation by means of ventilation process, approximately 0.5 10C temperature with 90% RH in the chamber is maintained. Ice Bank Cooler / Air forced cooler leads to desiccation of the produce (Plate 359). So use forced air high humidity cooler and these are known as Ice Bank Cooler. Ice bank coolers are useful for strawberry. Ice cream: Ice cream may be define as frozen dairy product made by suitable blending and processing of cream and other milk products together with sugar and flavour. Ice cream cone: A thin crisp edible cone for holding ice cream and filled with ice cream. Ice point: It is the temperature of equilibrium between ice and water under normal atmospheric pressure (Plate 360). Ichthylogy: It is the branch of the zoology that deals with the study of fishes (Pisces). Icicle: It is small tapering piece of the ice formed by freezing of dropping water (Plate 361).

Jaggery: Raw brown / unrefined brown sugar in lump made from palm sap (Plate 365). Jam: A preserved product prepared on boiling pectin contained in fruit pulp with required amount of sugar, water and acid to a reasonably thick consistency, firm enough to hold the fruit tissues in position (Plate 366). Jam pack: The packing of the commodity tightly or in excess is called Jam pack. Jamaica rum: Heavy bodied rum made by slow fermentation and marked by a pungent bouquet. Jamboline: A type of glucose found in the jamun fruit help in cure of the diabetes in the patients. Jelly: A product prepared by boiling clear extract of fruits with sugar. It should be transparent, well set, and tender enough to quiver but not flower and when cut; it should retain its shape and show a clean cut surface (Plate 367).

K ration: It is a lightweight packaged ration of emergency foods developed for the U.S. armed forces in World War II (Plate 371). Kaiser rolls: A round crusty roll often used for sandwiches (Plate 372). Kalamata /calamata: It is brine cured black olive grown in Greece. Kamucha: Tea cider or fermented tea beverages is known as kamucha. The fermentation process take place by the presence of yeast and bacteria Kanji: Clean, black coloured, crisp and sound product of characteristic flavor prepared by full fermentation (chiefly lactic acid fermentation) of black carrot with 2.5% salt, 1% powder mustard and some amount of water. It is fermented to make ready to serve drink which is known as Kanji. Each kilogram of the grated carrots yields just 7-8 litres of kanji. Karl Fischer Titration: Karl Fischer Titration is used for estimation of moisture content of foods (low moisture products). Kasseri cheese: The simple unpasteurized sheep’s milk cheese (sometimes mixed with goat’s milk) is called kasseri. It is popular in Greece. It is made in the shape of wheel, fairly firm and pale yellow (Plate 373). The word kasseri comes from the Turkish kasar which means that it has ability to hold its shape when heated.

Lab coat: A loose white coat with deep pockets that is worn in a laboratory or medical office. Labelling: It means any written, printed or graphic matter that is present on the label, accompanies the food or is displayed near the food, including that for the purpose of promoting its sale or disposal. After packaging, labels are required on the finished products intended for distribution and sale. Labelling can reflect on the quality of the product. It must be clear and informative. Information includes Name of the Manufacturer, Date of Manufacture, Net Weight, Gross Weight, Best before etc. Proper storage is needed for maintenance of the quality. Storage must be done only at recommended temperature, relative humidity, light and air / oxygen and carbon dioxide conditions etc. to maintain the quality of the food product. Label may include tag, brand, and pictorial or descriptive matter, written, printed, embossed, graphic, perforated, stencilled or stamped impressions. It is attached to container, cover, lid, or crown of a food package (Plate 384). Laboratory: A place equipped for experimental study in a science or for testing and analysis. Broadly, it is a place providing opportunity for experimentation, observation, or practice in a field of study. Lacquer: It is a colloidal dispersion of a solution of cellulose derivative, resin and plasticizer in solvent and diluents, where in all these constituents dried in air by evaporation of solvents, thus yielding a transparent, hard and water proof film.

Macaroni: Pasta made from semolina and shaped in the form of slender tubes (Plate 396). Macaroni wheat: It is tetraploid wheat and is preferred for making macaroni, vermicelli etc. Macaroon: A small cookie composed chiefly of egg whites, sugar, and ground almonds or coconut (Plate 397). Mace: An aromatic spice consisting of the dried external fibrous covering of a nutmeg (Plate 398). Mach number: It is a number representing the ratio of the speed of a body (flow velocity) to the speed of sound (sonic velocity) in a surrounding medium (as air). Macroglobulin: A highly polymerized globulin of high molecular weight. Macronutrient: A chemical element (as nitrogen, phosphorus, or potassium) of which relatively large quantities are essential to the growth and health of a plant or a substance (as protein or carbohydrate) essential in large amounts to the growth and health of an animal.

Naïve panel: It refers to the sensory evaluation panel that has not been trained specifically regarding the product evaluation being undertaken in the study. It is untrained panel of sensory evaluation. Nano technology: It is the art of manipulating materials on an atomic or molecular scale to build microscopic devices. The word “nano’ meaning ‘dwarf” in Greek language refers to dimension / magnitude of the material / particle in the order of 10-9. Nanotechnology is nothing but manipulating of particles into very small particles called nano-particles. These particles have dimensions in the scale of nano-meter and used to design / build materials and devices. Nanotechnology has been provisionally defined as relating to materials, systems and processes which operate at a scale of 100 nanometers (nm) or less. It will allow many things to be manufactured at low cost and with no pollution. The concept of nanotechnology was first given by Nobel Laureate physicist Richard P. Feynman in Southern California in 1959. NaNO2 : Pink colour of cured meat is preserved by NaNO2 . It is effective against Cl. Botulinosm Nanogram: It is one billionth of a gram. Nano-materials: Nano material have been defined as having one or more dimensions measuring 100 nm or less, or having at least one dimension at this scale which affects the materials behavior and properties (Plate 438).

Objective Methods: Objective Methods are used for evaluation of food quality. These are based on recognized standard scientific tests to any sample of the product without regard to its previous history. They represent the modern idea in quality control (QC) because the human element has been excluded. This method divided into three groups like physical, chemical and microbiological. The devices are used in this evaluation. Obligate aerobes: These microbes grow only in the presence of oxygen (Plate 450). Obligate anaerobes: These microbes do no grow in the presence of oxygen (Plate 450). Obligate parasite: Obligate parasites is host specific and grows on living host only and attach limited range of host and are very difficult or impossible to grow on artificial culture/media. Obligate thermophile: These microorganisms grow at a temperature between 38-80oC. Oenology: Treatments used to prevent spoilage of wine is called oenology. It is synonym to that of enology. Offal: It is the viscera and trimmings of a butchered animal removed in dressing of meat. It is by-product of slaughtering process.

Pack inspection: It is similar to continuous inspection except that here inspector(s) may make in-process checks during different processing operations under contract but not required to be present all the times in the plant during operation. Package: The package means a pre packed box, tin, barrel, pouch or can etc in which food article is packed. Package store: A store that sells bottled or canned alcoholic beverages for consumption off the premises. Packaging: Packaging is an industrial and marketing technique for containing, protecting, identifying and facilitating the sale and distribution of agricultural, industrial and consumer products (Plate 467). Packaging is defined as an enclosure of products, items or package in a wrapped pouch, bags, box, cup, bottle or any container form to perform one or more of the functions as containment, protection and preservation, communication and utility or performance. Technically, packaging is a system or method by which a product from the manufacturing point to the consumer level reaches in a safe and sound condition at an affordable cost. The primary purpose of the packaging is to protect the food product, to keep it in good condition and to preserve the flavour until it reaches the consumer. It is therefore, very essential that a suitable form of the packaging is chosen for a finished product. Packaging is an art, which determines the buying decision of a consumer. or Wrapping / placement of objects in paper / other packaging materials, keeping in box, etc is known as packaging which has two main functions, to assemble the produce / objects in convenient units for handling and to protect them during transporting, marketing and storage which results in extended shelf life of the produce. “Packaging” play a very important role not only in ensuring safety of the product during transportation, storage and distribution and in conveying information about the pack contents to the consumers, but also ensuring desired sensory characteristics and micro biological soundless till consumed.

Q10 value: The number of times a reaction rate change with a 10oC change in temperature is called Q10 value. If reaction rate doubles with 10oC change in temperature, Q10 = 2. It is also called temperature quotient. Q-enzyme: It is a branching enzyme responsible for formation of 1-6 bonds in amylopectin. QHV process: It stands for Quality Has Value Process. QO2 : It is a unit for measurement of respiration. Or It is the oxygen uptake in microlitres per milligram on dry weight per hour. Quailing: In this practice the oranges are kept in the baskets in which they are harvested to allow the fruit to loose little moisture. It is done for a couple of hours before transport to packhouse. This practice would allow the fruit to lose a little moisture which is called quailing. This operation is done for oranges to prevent Oleocellosis. Qualitative measurement: It is a subjective / objective measurement of the quality of the product for presence of certain compound. It gives the idea of the presence or absence of the particular compound. It deals with the nature of the substance and not its amount or quantity.

R - Enamel can: The acid resistant, gold coloured enamel treated can are called R enamel cans. It is used for canning of acidic food which have soluble colouring pigments. R value: R value is a measure of resistance to the flow of heat through a given thickness of a material (insulation) with higher numbers indicating better insulating properties. R-Value is a measure of insulation’s ability to resist heat traveling through it. The higher the R-Value the better the thermal performance of the insulation. Rabbitto and putridity: The surface taint of the milk caused by Pseudomonas putrefaciens is called rabbitto and putridity. Racking: An important operation for the wine production in which wine is siphoned off and is transferred to a fresh vat with the help of a false bottom. Racking is repeated decanting to remove the slowly setting cloud of the freshly fermented young wine. It is also called clarification. It is synonym to siphoning.

Saccharification: The process of breaking a complex carbohydrate (starch or cellulose) into its monosaccharide components is called saccharification. Saccharimeter: A device (polarimeter) used for measuring the amount of sugar in a solution is called saccharimeter. It is also known as saccharometer. It is a hydrometer with a special scale. Saccharin: A crystalline compound C7 H5 NO3 S that is unrelated to the carbohydrates, is several hundred times sweeter than sucrose, and is used as a calorie free sweetener. Saccharomyces: It is one of the genus (Saccharomyces) of the family Saccharomycetaceae and is usually unicellular yeasts (brewer’s yeast) that are distinguished by their sparse or absent mycelium and reproduced asexually by budding. Safe food: Food that provide maximum nutrition and quality while revealing a minimal hazard to public health and they assume any risk present to be minimal.

Table cream: It is also called coffee cream, single cream or homogenized cream. It is used in coffee and tests about 20% butter fat. Table oil expeller: It is a type of the machine that is used for extraction of the oil from the oil seeds (Plate 588). Table ready meat: Cooked and smoked sausages are called table ready meat. Tal prolong: This wax is esters of fatty acid glycosides NaCMC. TAME: It stands for p-Toluene sulfonyl L- arginine methyl ester. It is used in isolation of Trypsin inhibitor.

U value: U value is a measure of the heat transmission through a building part (wall or window) or through a given thickness of a material (insulation). U values with lower numbers indicate better insulating properties (Plate 614). UHT milk: This milk is homogenized, heated to atleast 135oC for about 2-3 second, cooled rapidly and then packed in sterilized containers aseptically. The milk in packs can be stored for several months without refrigeration. The nutrient loss is negligible. Used for making yogurt commercially as it does not need to be boiled again. UHT pasteurization: The milk is heated to ~150oC for a fraction of seconds practically no holding period. It is also called ultra pasteurization. UHT sterilization: It is method in which food is sterilized, cooled and then aseptically placed in previously sterilized containers which are subsequently sealed in an aseptic environment.

Vacreation: The pasteurization of the milk or cream under reduced pressure by direct steam is called vacreation. This process removes feed and other volatile flavors from cream and to pasteurize it for butter making. This is also called vacuum pasteurization (Plate 623). Vacuum: The state of negative pressure. It is equal to atmospheric pressure minus absolute pressure. Vacuum cooling: A technique of cooling vegetable (leafy vegetables, asparagus, brussels sprouts) having a high surface to volume ratio; rapidly and uniformly by boiling off some of their water at 10C and at low pressure (5 mm of Hg) into a sealed container. The produce is cooled by evaporation of water from the tissue surface and is more rapid than hydro cooling (Plate 624). Vacuum drier: A drier used to dry heat sensitive products where low pressure lowers the temperature, helps to retain natural flavour and minimizes oxidation and browning is called vacuum drier (Plate 625).

Wafer: A thin crisp cake, candy, cracker or chips is known as wafer. Waffle: A crisp cake of batter baked in a waffle iron is called waffle Warner-Bartzler Shear: It is one of the oldest but commonly used devices used to measure the tenderness of meat. It is used to test the quality in the cooked meat (Plate 648). Wastage: Wastage is a term that cannot be precisely defined by even moral value / judgment and defined on the context / situation on which it is used. Waste water: Water that has been used in a manufacturing process and goes waste is called waste water. Water: Water (H2 O) is a clear transparent, colourless, odourless and tasteless liquid; neutral in reaction; boils at 100oC, freezes at 0oC and has maximum density (1 g/cm3) at 4oC. It exists as snow, ponds, lake, rivers, seas, oceans etc., also occur as rain and is there in the form of moisture in atmosphere. Pure water is bad conductor of heat and electricity. Water is an essential part of the body structure as a carrier of nutrients and regulator of a number of body functions. Fruit and vegetables contain > 80% water and sometime upto 95% water e.g. cucumber, lettuce, marrow, lettuce, melon. The starchy tubers and seeds, for example yam, cassava and cork, contain less water, but even > 50%. So water content must be optimum at the harvesting time. The human body comprises of about 65 % water, while that of fruits and vegetables 80-90% water.

Xanthan gum: It is a polysaccharide that is produced by fermentation of carbohydrates by a gram-negative bacterium (Xanthomonas campestris) and is a thickening and suspending agent used in pharmaceuticals and prepared foods. It is also called xanthan. Xanthan is a stabilizer produced by Xanthomonas compestris (Plate 671). Xanthan is not hydrolysed or degraded by humans. Xanthones: It is a group of yellow pigments e.g. mangiferin in mango, Xanthophyll: Yellow hydroxyl carotene derivative which is present in all green leaves together with chlorophyll and carotene. Xanthophyll is a pigment containing O2 derived from carotene (Plate 672). Xerophilous: An organism which is thriving in or tolerant to a xeric environment is called xerophilous.

Yabby: It is one of the burrowing Australian crayfishes (Cherax destructor) that are used for food. Yakitori: A bite-size marinated pieces of beef, seafood, or chicken on skewers is called yakitori. Yam: It is edible starchy tuberous root of plants (genus Dioscorea of the family Dioscoreaceae) used as a staple food in tropical areas (Plate 676). Yautia: It is one of the aroid plants (Xanthosoma sagittifolium) chiefly of tropical America with starchy edible shaggy brown tubers that are cooked and eaten like yams or potatoes (Plate 677). Yearling mutton: Meat obtained from 12-20 month aged sheep. It is also called Earling mutton. Yeast: Unicellular plant body, very minute in size containing cell wall, cytoplasm with one or more vacuoles and a single nucleus, cause alcoholic fermentation (Plate 678). Yeast usually has little or no mycelium, and reproduces by budding. It results in production of yellowish surface froth or sediment that occurs in saccharine liquids (fruit juices) in which it promotes alcoholic fermentation, consists largely of cells of a fungus (as the saccharomyces, Saccharomyces cerevisiae), and is used in the making of alcoholic liquors and as a leaven in baking.

Zeatin: Zeatin is a cytokinin C10 H13 N5 O first isolated from the endosperm of Indian corn. Zeaxanthin: Zeaxanthin is an isomer of lutein occurring in fruits and vegetables (spinach and corn) (Plate 682, 683 and 684). Zein: Zein is a protein from Indian corn that lacks lysine and tryptophan and is used in making textile fibers, plastics, printing inks, edible coatings, adhesives and sizes. Zeolite: It is clay embedded in the plastic film to adsorb ethylene. It is used in Japan. Zeolite is anhydrous silicates that is analogous in composition to the feldspars and used in water softening, adsorbents and catalysts. Or Zeolite is one of various hydrous silicates that are analogous in composition to the feldspars, occur as secondary minerals in cavities of lavas, and can act as ion-exchangers. These are used especially in water softening and as adsorbents and catalysts (Plate 685). Zero 2: It is Australian oxygen scavenging plastic packaging materials.