Food Science Commons^™

Activation Of Prorennin, Nazar A. Shukri

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Purified prorennin appeared to be homogeneous when subjected to chromatography on a Diethylaminoethyl-cellulose and to electrophoreses in starch-urea-gel. Crystalline rennin was heterogeneous, and was resolved into six components when analyzed electrophoretically. When crystalline rennin was chromatographed on a column of Diethylaminoethyl-cellulose two distinguishable peaks were observed which corresponded to B- and C-rennin. Unlike crystalline rennin, rennin freshly activated at pH 2.0 or 5.0 was essentially homogeneous.

Rennin resulting from activation at pH 2.0 and 5.0 appeared to be different. Rennin activated at pH 5.0 was eluted faster from Diethylaminoethyl-cellulose column, and moved slightly faster in starch-urea-gel electrophoresis, than rennin activated …

Quality Of Beef Roasts: Electronic Versus Conventional Cooking, Frances Glassett Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of breed, backfat thickness, and methods of cooking on quality of beef roasts was determined by sensory and objective methods. Arm and rib roasts from Hereford, Shorthorn, Charolais, and Shorthorn-Charolais animals were cooked by several methods.

Roasts of the ninth to twelfth ribs were all dry roasted at 325 Farenheit. Boned and unboned roasts (sixth to eighth ribs) were cooked by conventional and electronic methods. Only significant results are reported herein.

Objective tests using the Warner-Bratzler shear indicated roasts of Shorthorn animals to be the most tender of the four breeds.

Sensory analysis by an experienced panel of …

Survival And Distribution Of Rennin During Cheddar Cheese Manufacture, John Ta-Chuang Wang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Residual rennin in cheese whey and curd was measured by using a special sensitive substrate. The substrate was made by reconstituting 6 g NDM in 500 ml of buffer containing 0.2 M CaCl₂, 0.5 M cacodylic acid and 0.2 M triethanolamine at pH 5.7. Cheese curd was blended into a 1:7 slurry (1 part curd, 7 parts water), and 1.67% sodium chloride was added to the whey and slurry to liberate residual rennin from casein. The residual rennin in cheese whey and slurry were determined simultaneously with an identical sample containing known rennin activity. Samples with known activity …

Analysis Of Fruit Juices And Drinks Of Ascorbic Acid Content, Anna Man-Saw Liu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A total of 33 common fruit juices and drinks representing 15 different fruits were analyzed for ascorbic acid content by a slight modification of the method of Loeffler and Ponting (1942). The juices ranged from 0.96 to 50.88 mg per 100 ml. The drinks ranged from 2.12 to 66.10 mg. All the citrus juices ranked high in ascorbic acid content. One drink was fortified with sufficient ascorbic acid to contain considerably more vitamin than was found in pure orange juice.

The ascorbic acid values of different forms of orange drinks and pure orange juices were compared. Except for one brand, …

Effects Of Gamma Radiation In Concurrence With Certain Environmental Conditions On Lethal And Physio-Chemical Responses Of Penicillium Expansum L., Tsong-Wen Chou

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In vitro investigations were conducted to study the lethal effect of gamma radiation on the fruit spoilage fungus Penicillium expansum under certain environmental conditions, and to study some physio-chemical changes in the fungus induced by the radiation which may be related to the death of the fungus or its ability to invade fruits.

The radiation sensitivity of P. expansum conidia was influenced by such factors as nutritional condition of the post-irradiation media, age of the spores, delayed plating, heat treatment, and chemical sensitizers. Higher survival was obtained when irradiated conidia were plated on Czapek solution agar (sugar-salts medium) than on …

Accounting For Milk Protein In Equivalents By Dye Binding Analysis Of Cheese And Whey, Prahlad H. Patel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Each of thirteen lots of Cheddar cheese was made from 430 lb. of milk, and the protein recovered in the cheese and whey was compared with that in the original milk. Protein determinations on the milk, cheese and whey were made by an acid orange 12 dye binding test, and by Kjeldahl analysis. Similarly fat recovery was determined by using the Babcock fat test on milk, the modified Babcock test on cheese, and the Mojonnier test on whey. The total weight recovered as cheese and whey was 99 ± .6% by Kjeldahl analysis and 97.7 ± .6% by the dye …

Development Of A Low-Fat Spread, Clair L. Hicks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A stable low-fat water-in-oil emulsion was satisfactorily prepared from milk-fat under laboratory conditions. The best product contained 40 per cent fat, 56.8-57.3 per cent water, 0.8 per cent sodium carboxymethyl cellulose, 0.7-1.2 per cent milk solids-non-fat, and 1.2 percent salt. The spread was prepared equally well from butter or high test cream. When the product was made from cream (containing 74 per cent milk-fat) it was necessary to convert most of the globular fat to free fat prior to forming an emulsion. Globular fat in cream was successfully changed to free fat by homogenization at 2500 pounds per square inch …

Rennin Content Of Abomasa From Bovine Fetuses, Suk Hoon Pang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rennet extract is an important commercial enzyme preparation which is indispensable to the cheese making industry, The term "rennet" is used to denote the enzyme system extracted from the fourth stomach (abomasum) of a suckling calf. Most of the enzymatic material in the extract is rennin. It also contains a small amount of pepsin(15) and some other proteolytic enzymes(4). The amount of pepsin in rennet extract appears to depend upon the age of the calves at the time of slaughter(31).

Adaptive Changes Of Some Enzyme Activities In Rats And Humans To Dietary Protein, Jung Ja Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study of the adaptive changes of some enzyme activities to the dietary protein intake was made in the liver, kidney, and pancreas of rats and serum of humans.

The rats fed the 40 per cent casein diet had a higher rate of weight gain and the weights of the liver and kidney were higher than in the rats fed the 10 per cent casein diet.

Three enzymes involved in the elimination of excess nitrogen from the body were found to show a similar response to increased dietary protein intake. These enzymes were: D-amino acid oxidase in the kidneys, arginase …

Effects Of Ripening Processes On Chemistry Of Tomato Volatiles, Bharat Manu Shah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investigations were carried out to isolate, identify, and to characterize, major volatile components of tomato fruit. Simultaneously, the confirmation was extended to the reported tomato volatiles. The volatile extracts from field- and artificially-ripe fruits were compared qualitatively as well as quantitatively. The changes which occurred in the volatile components of the fruit at the onset of senescence also were delineated.

A typical chromatogram from field-ripe tomatoes contained 60 peaks. The functional group properties of individual peaks were derived by chemical analysis. The short-chain (C₃-C₆) alcohols represented 10 per cent, aldehydes and ketones 32 per cent, and …

Food And Nutritional Needs Of The World Population By 2000 A. D., Sitaram Shankar Kharbas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Investigations were carried out to project the food needs of the world population by 2000 A. D., and to explore the possibilities of meeting these requirements.

About 70 percent of the world population presently living in developing countries do not get adequate diets, and suffer from many diseases of under-nutrition and malnutrition. They are unable to increase food production themselves. People in the developed nations have enough food and their food production is increasing at a rate faster than the rate of growth of population.

Cultivable land is the main source of food for man. The seas can also be …

Isolation, Identification, And Comparison Of The Volatiles Of Peach (Prunus Persica L., Cultivar, Gleason Early Elberta) Fruit As Related To Harvest Maturity And Artificial Ripening, Joseph Yungsheng Do

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Volatiles of peach (Prunus persica L., cultivar, Gleason Early Elberta) fruit were studied by gas-liquid chromatography, thin-layer chromatography, and infrared spectrometry. Hard mature, firm mature, soft mature, tree ripe, and artificially ripened hard mature fruit obtained from four seasons, 1964 to 1967, were used. A total of 86 peaks were observed in the chromatogram of the tree ripe peach volatiles. Major components of the volatiles identified were mainly esters, gamma and delta lactones, aldehydes, alcohols, and terpenes. In general, concentration of the volatile components were found to increase with the maturity of the fruit. However, that of the artificially …

Extraction Of Rennet From Fresh Frozen Vells, Neil Harvey Clarke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A method was developed for the extraction of rennet from fresh frozen vells. Frozen vells were partially thawed and minced in a Hobart "Wonder worker." The tissue was treated with 2.0 per cent potassium alum and allowed to stand for 20 hours before sufficient 0.45 M disodium phosphate was added to bring the pH of the mixture to 5.7. Dry sodium chloride was added until the salt concentration in the moisture of the mixture was 10 per cent. The tissue was then mixed with 3/4-inch pumice gravel in a volume ratio of 1 to 2 and packed into extractor columns. …

Influence Of Pre-Fermentation Inoculations With Leuconostoc Mesenteroides And Lactobacillus Plantarum On Physico-Chemical Properties Of Fresh And Dehydrated Sauerkraut, William T. Nabors

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect Leuconostoc mesenteroides and Lactobacillus plantarum has on the physical and chemical properties of fresh and dehydrated sauerkraut was tested. Sauerkraut inoculated with L. plantarum was slower in fermenting and significantly lower in acidity and higher in pH. Dehydration of sauerkraut by freeze-conventional hot-air and micro-wave processes produced a significant loss in volatile components, ascorbic acid , lactic acid and an increase in pH. Each of the dehydration processes caused browning of the sauerkraut . These changes were less with freeze-drying and increased with conventional hot-air drying and microwave drying. Gas-liquid chromatography confirms the loss of volatile components …

The Influence Of Hot Brine On The Calcium Content, Score, And Physical Properties Of Low-Fat, Cheddar-Like Cheese, Robert V. Ogden

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two factors that are important in the production of the typical body and texture of cheddar cheese are acid development and milk fat content. When either of these is absent or present in less-than-normal amounts, the resulting cheese shows marked defects of curdiness and firmness.

When acid development in a vat of cheese is arrested, it is referred to as a "dead" vat. The cheese from this vat may be salvaged by use of the hot brine method of treatment. Hot brine treated cheese, although lacking the desired acid development, is a reasonably acceptable product, having the desired characteristics of …

Serum Alpha-Tocopherol, Cholesterol, And Total Lipid Values And Unsaturation Of Lipids In 33- To 60-Year Old Adults On Self-Selected Diets At Different Levels Of Polyunsaturated Fat, Marjorie Miner Christiansen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The levels and weekly variations of certain lipid components were investigated in healthy adults, 33 to 60 years of age, on self-selected diets under home-living conditions with and without an increased proportion of polyunsaturated fats for a period of 26 weeks. Ten individuals served as controls and 16 were assigned to the experimental diet. Each of the groups contained an equal number of men and women. The experimental diet provided a ratio of polyunsaturated to saturated fatty acids of approximately one, with the substitution of vegetable oils for animal fats within the normal eating patterns of the participants. The control …

Amino Acids As Precursors Of Volatile Components In Tomato Fruit, Ming-Ho Yu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The composition of tomato fruit at nine different maturity stages was studied. The dry matter content decreased gradually, whereas the alcohol soluble material and non-protein nitrogen increased with ripening. Total nitrogen decreased up to the large green stage and then increased during ripening. Starch accumulated until nearly the large green stage and then diminished rapidly. Of the two components of starch, amylose decreased much faster than amylopectin, and the ratios of amylopectin and amylose thus increased during ripening. Among the amino acids, glutamic acid was present in an exceptionally high concentration, and its concentration doubled as the fruit ripened. A …

Influence Of Phosphate Compounds On Certain Fungi And Preservative Effects Of The Compounds On Fresh Cherry Fruit (Prunus Cerasus, L.), William Sidney Coblentz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were conducted using four phosphate compounds: sodium hexametaphosphate, sodium tripolyphosphate, sodium tetraphosphate, and tetrasodium pyrophosphate at 1, 5, and 10 per cent concentrations to ascertain their effects on fresh cherries, as well as their in vitro antimycotic effects against Botrytis sp., Penicillium expansum, and Rhizopus nigricans.

A. summary of the findings are as follows:

1. Sodium tetraphosphate appeared to be the most effective antimycotic compound used in this investigation. A 10 per cent concentration of sodium tetraphosphate appeared to be the most effective antimycotic compound used in this investigation. A 10 per cent concentration of sodium tetraphosphate inhibited …

Effect Of Large Doses Of Nicotinic Acid On The Lipid Composition Of Serum, Shu Hua Chen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although much information is available in which the cholesterol level and concentration of other lipids in serum have been studied, only limited data have been reported for normal human adults and concentrations of fatty acids composition of lipid classes in serum. In recent study in this laboratory, five male adults who were in good health served as experimental subjects. They were on a self-chosen diet and received a test dose of Nicospan (buffered nicotinic acid) of 2 gm per day for three weeks of a six-week test period. About 30 ml of venous blood were obtained twice weekly from each …

Serum Lipid Components Of University Women During The Menstrual Cycle, Hih-Min Sang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Four healthy university women students (age 21-26) while on self-selected diets and living under normal living conditions served as experimental subjects in a study of changes of serum total lipids, distribution of lipid classes, and the fatty acid composition of lipid fractions during the menstrual cycle. Effect of meal frequency (2 meals vs 3 meals with no breakfast) was also included.

Total lipids were extracted from serum. Chemical determinations of total lipids, total and free cholesterols, and lipid phosphorous were made on these extracts. Concentration of cholesterol esters and phospholipids were calculated and triglycerides plus free fatty acids were calculated …

Lipid Composition Of Human Red Blood Cells And White Blood Cell-Platelets With And Without Administration Of Nicotinic Acid, Nuggehalli Narayan Tara

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Five normal, healthy, men (age 33-42) served as experimental subjects. The subjects were on self-chosen diets and received a test-dose of buffered nicotinic acid (Nico-Span in capsule form) of 2 gm daily for three weeks, from the second through the fourth weeks, of the six and one-half week test period. About 30 ml of venous blood was obtained twice weekly from each subject, after an overnight fast of at least 12 hours. Each subject collected a 24-hour urine sample of the day prior to the blood sampling and also kept a record of food eaten.

The blood was separated into …

Venison Flavor: The Free Fatty Acid Content Of Fat From Lean Meat Tissue, Von T. Mendenhall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Millions of pounds of venison are harvested each year in the United States. Over 12,000,000 pounds of dressed venison are harvested during the regular season each year in the State of Utah. The hunters of venison contribute approximately 10 1/2 billion dollars to the economy of the state for licenses, lodging, transportation, and other expense of hunting. In many cases this source of meat is a significant part of the household meat supply. Venison is often wasted, however, because of its undesirable flavor. The lack of knowledge as to the causes of variation in venison flavor has prompted this study. …

Effects Of Dehydration Processes With Special Reference To Microwave Irradiation On Selected Biochemical And Physical Changes In Apples (Pyrus Malus), Fredoon Shahin Nury

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many innovations have been attempted to shorten drying time or improve dehydration techniques for foods. Despite the recent advances in science and technology the bulk of dried fruit production throughout the world, over 1 1/2 billion tons (dry basis), is prepared by the energy of the sun (Copley and Van Arsdel, 1964). However, other techniques and processes for food dehydration and preservation are occupying more prominent positions in the overall production of dehydrated foods, particularly in the more advanced countries. Economics notwithstanding, it is readily apparent that dehydration as compared to sun-drying offers at least two main advantages. It is …

Comparative Effects Of Dehydration Processes On Physico-Chemical Changes In Fruits, Chang Yong Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Drying with the help of sun and wind is one of the oldest methods of food preservation known to man, but artificial drying, or dehydration, has been developed and used extensively only during the last two decades. The problem in dehydration is that the water content must be decreased sufficiently to maintain the stability of the product by retarding the rates of deteriorative biochemical, microbiological, and enzymatic reactions during subsequent storage. At the same time irreversible changes should not be brought about.

Breeding And Roasting Temperature As Related To Beef Tenderness And Other Quality Factors, Ruth Ann B. Jenson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

According to the 1964 census the production and sale of livestock provided a major source of income in the state of Utah. Twenty-three of the state's twenty-nine counties received more than 40 percent of their total farming income from livestock sales in 1959. According to Taylor (1965) this is expected to increase even more. In studying the economic sources within Utah, it becomes evident that many of the state's farmers and ranchers depend heavily on the sale of livestock for their livelihood. Upon observing this fact, Taylor (1965) states that farm income will depend just as heavily on the sale …

Cholesterol Levels In Serum And 5Β – Pregnane – 3Α,20Α - Diol In Urine Of University Students, Gertrude Kuei-Shu Chiang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since there is a high incidence of coronary heart disease in humans of middle-age and older in the United States, and the mortality of this disease is still increasing, a great deal of research has been done in this field. Although many theories have been formulated concerning the cause of atherosclerosis, it is a very complex disease, and appears to be influenced by many factors. Disturbed lipid metabolism is widely believed to be involved in the development of the vascular lesions found in arteriosclerosis, although the nature and origin of the disturbance is unknown. The mechanism for the elevation of …

Potentiometric Measurement Of Sodium Chloride In Cheese, Seyed-Hossein Salimi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The salt content of cheese is usually determined by the American Dairy Science Association (ADSA) (26) procedure. This method is based upon the determination of chloride in the sample, and results are expressed as per cent sodium chloride. The presence of chlorides in cheese other than sodium chloride would introduce error in the results. However, in practice this is not serious except where relatively large amounts of CaCl₂ are added to the cheese milk.

In determining the NaCl in cheese, one would be as justiied in basing his results on sodium analysis as on chloride analysis. An exception would …

A Two Year Course Outline In Quantity Foods For Intermountain High School Girls, June C. Larson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Bureau of Indian Affairs has recently completed or is now in the process of building 19 new grade schools on the Navajo reservation. Some of these schools are boarding schools, and some are day schools, but each new school needs school lunch personnel. To meet this need intermountain School added to their curriculum a course in Quantity Foods to be given to Junior and Senior High School girls as a two year vocation. This necessitated the development of a 2 year course outline for the 2 year Quantity Food class, which gave the girls 4 hours daily practical training …

Some Biochemical Changes Occurring In Tomato Fruit Ripened By Several Treatments, Arthur A. Boe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ripening of fruit, aside from its economic consequence, is of importance in the study of the development and physiology of plants. The fruit, being the reproductive organ of the plant, is fundamentally necessary for the continuation of the species. The production of fruit is also of major economic importance.

The fruit is nurtured, not only by its own ability when young to produce carbohydrates by photosynthesis, but also by the translocation of sugar and other compounds produced in the leaves. While young, the fruit appears to function as the modified leaf that it is believed to be. It is …

A Comparison Of Tests Used In The Selection Of Milk, Roger L. Stephens

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The selection of milk has for many years been based upon the use of bacteriological tests such as the standard plate count, methylene blue, and resazurin tests. Such tests demoted the numbers of bacteria in milk and thus were well accepted as a close correlation of sanitary practices on the farm.

However, improvements in equipment, cleaning procedures, sanitizers and handling methods have greatly improved milk quality over the past decade. The farm bulk tank is a much more efficient system of cooling use in many areas. However, its very efficiency in cooling milk poses many new problems for those engaged …