Abstract: The use of a target protein against which the quality of other dietary proteins could be compared has been examined in rats. Milk, the natural food during the early life of mammals, was proposed as the target standard. The milk standard diet was compared with proteins of different origins, amino acid pattern, or lacking an essential amino acid. A chemical score based on rat's milk (CSM-R) was developed to evaluate the quality of the protein diets; it combined determination of a protein's most limiting amino acid with a capacity for ranking proteins by nutritional values. Diets were evaluated for protein efficiency ration, body weight gain, levels of amino acids and protein complementation. Results indicated that rat milk contains a proportion of amino acids which provides maximum protein utilization in growing rats, and may also protect the lactating mother. Other diets were usually inferior. The CSM-R score appeared to be a useful analytic tool in evaluating the quality of dietary proteins.

Historical aspects of biological evaluation of protein quality are reported. A new method for such evaluation is proposed. Protein efficiency ratio (PER) is compared to Net Protein Ratio (NPR). NPR is further compared to Relative Protein Value (RPV). The implications of these comparisons for regulation of protein quality are discussed. It is proposed that PER be dropped as the regulatory method. A food serving should be expressed in terms of utilizable protein obtained by multiplying the weight of protein by the relative NPR.

A definition of terms in this research area is presented. A general approach for applying nondestructive quality evaluation (NDQE) to horticultural crops, for both fresh and processing purposes is discussed. The approach includes consideration of the importance of biochemical, morphological and physical parameters of quality. The objective and subjective determination of single and multiple parameter judgements of quality at different stages of physiological development is a critical part of this approach. The concept of “Optimum Quality Range” is presented in relation to the development of nondestructive quality evaluation techniques and applications.

The backbone for continued corporate financial success rests with the quality of the products developed and "maintained" by food technologists. Sensory evaluation takes the guesswork out of new product development and also contributes to marketing in the areas of reformulations and quality monitoring. Several ways to prevent being misled in early sensory evaluation work are listed. When used as a system of information feedback, with proper experimental design procedures and established data bases, the benefits of sensory evaluation are boundless.

Use of nondestructive quality evaluation techniques for agricultural products is steadily increasing. Reasons for increased application and refinements of techniques in processing of agricultural products are discussed, especially with regard to more automation and less labor in processing, increased processing rates, and demand for more quality and uniformity of product. Information is presented on a number of nondestructive techniques presently being used, and the need for additional development is covered. Special emphasis is given to the efficiency, practicality, and economic feasibility of various techniques. Agricultural products covered include peanuts, pecans, poultry, eggs, pork, and seeds. Nondestructive techniques discussed that are used for processing these commodities into uniform, high-quality products include visual examination, weighing, screening, gravity sorting, air classification, electronic sorting, and estimation of chemical composition. A more detailed discussion of electronic color sorting of peanuts, pecans and almonds is presented, particularly in relation to aflatoxin sampling and reduction, preparing for further processing, and evaluation of commercial sorters for speed and accuracy.