K. F. Mattil

Aqueous extraction—An alternative oilseed milling process

Oil can be removed from oilseed materials by a process which consists of an aqueous extraction of the comminuted seed, followed by a centrifugal separation which divides the aqueous extract into oil, solid, and aqueous phases. The protein may be recovered in the solids or aqueous phase, depending upon the conditions selected. Unit operations of this process are grinding, solid-liquid separation, centrifugation, demulsification, and drying of products. Aqueous extraction has been applied, to date, to coconuts and peanuts. For coconuts, a procedure has been developed to recover 93% of the oil and 91% of the protein. The major protein product is 25% protein and, when reconstituted in water, forms an acceptable beverage. The estimated production cost of this product is

The functional requirements of proteins for foods

.24/1b. For peanuts, the recovery of oil was 89% and protein 92% for the concentrate procedure, whereas the corresponding values for the isolate procedure were 86% and 89%, respectively. The costs of production were estimated as

Evaluation of the food use potential of sixteen varieties of cottonseed

.17/1b of concentrate (67% protein) and

Critical unit operations of the aqueous processing of fresh coconuts

.28/1b of isolate (89% protein). Aqueous extraction offers several advantages over conventional solvent extraction-less initial capital investments, safer operation, capability of discontinuous operation, and production of a variety of products. Another advantage of aqueous processing is the capability for utilization of certain chemicals to remove or inactivate undesirable substances. In the case of peanuts, hydrogen peroxide and sodium hypoehlorite have proven to be effective for destruetion of aflatoxins. Aqueous processing has the potential for application to a variety of other oilseeds.

Destruction of aflatoxins in peanut protein isolates by sodium hypochlorite

As a growing amount of research attention has been diverted, for a number of reasons, from the traditional protein foods to the so-called unconventional food proteins, an awareness has increased of the need to understand the functional properties of these proteins. Some empirical functionality tests have been devised, but it is submitted that many of these could yield misleading information, inasmuch as they often ignore or even run counter to the environmental interactions to which proteins are exposed in food systems. Some examples are given of the influence of the ionic environment upon one basic functional property of proteins, their solubility in aqueous solution.

Composition, nutritional, and functional properties, and quality criteria of soy protein concentrates and soy protein isolates

Abstract and SummarySixteen new or experimental varieties of cotton-seed, eight glandless and eitht glanded, were extensively analyzed in this study. Ginned seed from each were studied and then kernel samples and finally oil and flour samples prepared from the kernels. Mean values determined for each attribute measured are presented for each type seed. These data are useful for (a) showing the magnitude of particular desirable properties presently being achieved in varieties of each type seed, (b) showing something of the variation of these properties among varieties within seed types, and (c) comparing glandless and glanded seed types for compositional differences.

Cottonseed protein food products

An aqueous process was investigated for the recovery of oil and food grade protein from fresh coconuts. Efficient recovery of oil, which is very important for economical reasons, was related to three critical unit operations: separation of oil from the fiber, destabilization of an oil-in-water emulsion, and recovery of a protein product that is low in oil content. The material balance is reported for a laboratory process that satisfactorily separates oil and breaks the emulsion, and data are shown which has led to a process for recovery of a protein with low oil content.

Processing edible peanut protein concentrates and isolates to inactivate aflatoxins

Sodium hypochlorite has been tested for destruction of aflatoxins during the preparation of peanut protein isolates from raw peanuts and defatted peanut meal. The treatments were evaluated by determination of the aflatoxins in the products by thin layer chromatography. Effects of sodium hypochlorite concentration, reaction pH, temperature, and time were studied. Results show that both the sodium hypochlorite concentration and pH are important factors in reducing the concentration of aflatoxins in the protein isolates to nondetectable levels. The treatment with 0.4% sodium hypochlorite at pH 8 produced protein isolates with trace amounts of aflatoxins B1 and B2 from ground raw peanuts containing 725 ppb aflatoxin B1 and 148 ppb aflatoxin B2, whereas untreated protein isolates contained 384 ppb aflatoxin B1 and 76 ppb aflatoxin B2. At pH 9, 0.3% sodium hypochlorite reduced the aflatoxin B1 content in the protein isolates from 300 ppb to below detectable quantities and the aflatoxin B2 content from 52 ppb to 2 ppb. Similar results were obtained at pH 10 for 0.3% sodium hypochlorite concentration. In the case of defatted peanut meal which contained 136 ppb aflatoxin B1 and 36 ppb aflatoxin B2, 0.25% sodium hypochlorite concentration at pH 8 (0.20% at pH 9; 0.15% at pH 10) reduced both the aflatoxin B1 and B2 contents to below detectable quantities in protein isolates as compared to aflatoxin levels of ca. 75 ppb B1 and 17 ppb B2 in the untreated protein isolates. Reaction temperature and time did not affect the destruction of aflatoxins significantly.

Distribution of aflatoxins in various fractions separated from raw peanuts and defatted peanut meal

The available commercial soy protein concentrates and soy protein isolates afford the food processor concentrated sources of protein with some interesting and varied functional properties. Each class of products is mild to bland in flavor and light in color. The concentrates contain at least 70% protein and the isolates 90%. The nutritional quality of the proteins is fair to good and can be excellent either by supplementation with 1.5% methionine or by appropriate blending with other sources of proteins. The concentrates provide the food manufacturer with products where a high protein content for unit of volume or wt is needed. The isolates are available for uses where the functional properties reside solely in the protein and the nonprotein components may interfere. The adaptability of the proteins to modification by controlled processing conditions has made it possible for the manufacturers to produce a diversity of products that should be of interest to practically all food formulators.

Aqueous processing of coconuts: Economic analysis

Abstract and SummaryUpward trending world population and increasing costs for traditional food proteins provide many incentives for utilization of oilseed proteins directly in human diets. Cotton, as one of the worlds major oilseed crops, represents a potential source of food protein. Acceptability of oilseed protein products in terms of functional properties in food systems and nutritional value will largely determine the extent of their utilization by the food industry. Liquid cyclone process cottonseed flour, defatted glandless cottonseed flour, storage protein isolates, and cottonseed whey proteins have been evaluated by various functionality tests and in a number of food systems. The cottonseed flours have been subjected to processing by extrusion texturization. Human feeding studies have also been conducted. Results indicate a good potential for use of cottonseed protein products in a variety of food systems.