Effect of Fractionation and Processing Conditions on the Digestibility of Plant Proteins as Food Ingredients

Plant protein concentrates and isolates are used to produce alternatives to meat, dairy and eggs. Fractionation of ingredients and subsequent processing into food products modify the techno-functional and nutritional properties of proteins. The differences in composition and structure of plant proteins, in addition to the wide range of processing steps and conditions, can have ambivalent effects on protein digestibility. The objective of this review is to assess the current knowledge on the effect of processing of plant protein-rich ingredients on their digestibility. We obtained data on various fractionation conditions and processing after fractionation, including enzymatic hydrolysis, alkaline treatment, heating, high pressure, fermentation, complexation, extrusion, gelation, as well as oxidation and interactions with starch or fibre. We provide an overview of the effect of some processing steps for protein-rich ingredients from different crops, such as soybean, yellow pea, and lentil, among others. Some studies explored the effect of processing on the presence of antinutritional factors. A certain degree, and type, of processing can improve protein digestibility, while more extensive processing can be detrimental. We argue that processing, protein bioavailability and the digestibility of plant-based foods must be addressed in combination to truly improve the sustainability of the current food system.

Formulation and Evaluation of Functional Cookies for Improving Health of Primary School Children

BACKGROUND AND OBJECTIVE

School children especially in Egypt need a safe meal which is able to meet their daily nutrient needs and ameliorate cognition. So, the current study aimed to evaluate formula prepared as cookies to be served as a meal for primary school children.

MATERIALS AND METHODS

Wheat, roasted chickpea, milk protein concentrate, cinnamon and brewer's yeast were used to prepare cookies which have been exposed to sensory, chemical and biological evaluation. Peroxide number, amino acids, vitamins (D, B12, folic acid and E) and minerals (calcium, zinc, iron and selenium) were determined. Twenty four rats of weaning age were used, 12 rats to estimate the true protein digestibility and 12 rats to estimate the protein efficiency ratio and the effect of feeding on cookies (28 days) on hemoglobin, glucose, total protein, liver and kidney functions and antioxidant status.

RESULTS

Palatability and acceptability of cookies were insured via the sensory evaluation results. The value of peroxide number indicated that there is no possibility of rancidity during the storage. The cookies showed high contents of protein (14.88%), fat (16.83%) and carbohydrate (55.1%). Also cookies showed acceptable levels of amino acids, minerals and vitamins that meet a large amount of daily requirements of children. Results of the animal experiment declared the complete safety of the cookies and high nutritional and biological quality.

CONCLUSION

Cookies can serve as a meal for the governmental school children to provide them with their needs from nutrients that reducing hunger and improving health benefits and scholastic achievement.

Susceptibility of phaseolin to in vitro proteolysis is highly variable across common bean varieties (Phaseolus vulgaris)

A study was conducted to investigate the amino acid (AA) composition and the susceptibility to in vitro proteolysis (pepsin, 120 min and pancreatin, 240 min) of a collection of purified phaseolins ( n = 43) in unheated or heat-treated form. The AA composition of phaseolin varied little across bean varieties. At 360 min of in vitro proteolysis, the degree of hydrolysis varied from 11 to 27% for unheated and from 57 to 96% for heated phaseolins ( P < 0.001). Heat treatment markedly increased the susceptibility of phaseolin to proteolysis ( P < 0.001). The AA scores (AAS) and the protein digestibility corrected for AAS indicated S-containing AA as the limiting AA (39 +/- 3 and 30 +/- 5%, respectively). In conclusion, susceptibility to proteolysis of heat-treated phaseolin rather than its AA composition affects the nutritional value of phaseolin estimated in vitro. Therefore, it should be the criterion of choice in breeding programs aimed at improving the nutritional value of common beans for humans.

Proteínas do feijão preto sem casca: digestibilidade em animais convencionais e isentos de germes (germ-free)

O feijão (Phaseolus vulgaris, L. ) é uma leguminosa de grande importância para a dieta da população brasileira. No entanto, um de seus maiores problemas é representado pelo baixo valor nutricional de suas proteínas, decorrente, por um lado, da sua baixa digestibilidade e, de outro, do teor e biodisponibilidade reduzidos de aminoácidos sulfurados. Com o objetivo de avaliar a digestibilidade das proteínas albumina e globulina do feijão preto sem casca, foram realizados ensaios biológicos com camundongos isentos de germes e convencionais e com ratos (Wistar), recém-desmamados, com idade de 21 a 25 dias. Avaliou-se ainda o Escore Químico Corrigido pela Digestibilidade da Proteína. A digestibilidade verdadeira no experimento com camundongos isentos de germes foi de 90,21 e 90,00%, no teste com camundongos convencionais foi de 85,53 e 86,73%, e no experimento com ratos foi de 82,62 e 68,53%, para albumina e globulina, respectivamente. O Escore Químico Corrigido pela Digestibilidade da Proteína foi de 61,00% para a albumina e 51,00% para a globulina. A digestibilidade determinada em animais isentos de germes foi superior aos valores encontrados em animais convencionais, sugerindo que a flora intestinal esteja contribuindo para elevar o teor de nitrogênio nas fezes dos animais convencionais, e, portanto, esteja sendo subestimada a digestibilidade verdadeira do feijão.

Hard-to-cook phenomenon in common beans--a review

Legumes are one of the world's most important sources of food supply, especially in developing countries, in terms of food energy as well as nutrients. Common beans are a good source of proteins, vitamins (thiamine, riboflavin, niacin, vitamin B6) and certain minerals (Ca, Fe, Cu, Zn, P, K, and Mg). They are an excellent source of complex carbohydrates and polyunsaturated free fatty acids (linoleic, linolenic). However, common beans have several undesirable attributes, such as long cooking times, being enzyme inhibitors, phytates, flatus factors, and phenolic compounds, having a "beany" flavor, and being lectins and allergens, which should be removed or eliminated for effective utilization. Grain quality of common beans is determined by factors such as acceptability by the consumer, soaking characteristics, cooking quality, and nutritive value. Acceptability characteristics include a wide variety of attributes, such as grain size, shape, color, appearance, stability under storage conditions, cooking properties, quality of the product obtained, and flavor. Storage of common beans under adverse conditions of high temperature and high humidity renders them susceptible to a hardening phenomenon, also known as the hard-to-cook (HTC) defect. Beans with this defect are characterized by extended cooking times for cotyledon softening, are less acceptable to the consumer, and are of lower nutritive value. Mechanisms involved in the HTC defect have not been elucidated satisfactorily. Attempts to provide a definitive explanation of this phenomenon have not been successful. The most important hypotheses that have been proposed to explain the cause of bean hardening are (1) lipid oxidation and/or polymerization, (2) formation of insoluble pectates, (3) lignification of middle lamella, and (4) multiple mechanisms. Most researchers have reported that the defect develops in the cotyledons. Recently, some authors have suggested that the seed coat plays a significant role in the process of common bean hardening. A better knowledge of cotyledon and seed coat microstructure may lead to a better understanding of the causes of seed hardness. In order to prevent the development of the HTC defect several procedures have been proposed: (1) appropriate storage, (2) controlled atmospheres, and (3) pretreatments. Probably, the most workable solution to the hardening phenomenon may be the development of materials less prone to HTC phenomenon. Decreasing cooking time, increasing nutritive value, and improving sensory properties of seeds with HTC defect would have great nutritional and economical impact.(ABSTRACT TRUNCATED AT 400 WORDS)

Biochemistry and technology of chickpea (Cicer arietinum L.) seeds

Chickpea is an important source of proteins, carbohydrates, B-group vitamins, and certain minerals, particularly to the populations of developing nations. India contributes over 75% of the chickpea production in the world where it is mostly consumed as dhal, whole seeds, and several types of traditional, fermented, deep fried, sweetened, and puffed products. In this review, the world production and distribution, genetic background, biochemical and nutritional quality, and developments in storage and processing technology of chickpea are discussed. Future research needs, to improve the utilization of chickpea as human food, are addressed.

Chemistry and technology of green gram (Vigna radiata [L.] Wilczek)

Green gram or mung bean (Vigna radiata [L.] Wilczek) is an important food legume grown under tropical and subtropical conditions. It is an excellent source of protein and is almost free from flatulence-causing factors. Because of this, green gram seeds are preferred for feeding babies and those convalescing. The seeds contain a higher proportion of lysine than any other legume seeds. The seeds are processed and consumed as cooked whole beans or splits (dhals), sprouts, immature seeds, and flour and are used in various recipes. The proposed work will incorporate available information on nutritional composition, processing, and utilization of green gram. The results reported in the literature on the above aspects of green gram will be analyzed critically, and future research needs will be defined to improve the utilization of green gram as human food.

Pigeonpea as an important food source

Pigeonpea is an important source of proteins, carbohydrates, B-group vitamins, and certain minerals. India contributes over 90% of the pigeonpea production in the world where it is mostly consumed as dehusked splits or dhal. In African countries and Latin America, it is mainly consumed as canned peas. In this review, world production and distribution, genetic background, and biochemical and nutritional properties, storage and processing of pigeonpea are discussed. Future research needs to improve the utilization of pigeonpea as human food are also addressed.

Dry beans of Phaseolus. A review. Part 2. Chemical composition: carbohydrates, fiber, minerals, vitamins, and lipids

Beans of Phaseolus are an important food crop both economically and nutritionally, and are cultivated and consumed worldwide. With ever rising costs of meats and fresh fruits and vegetables, dry beans are expected to contribute more to the human nutrition in coming years. Traditionally, they have been referred to as "poor man's meat" and have contributed significantly to the diets of many people of several countries in Asia, Africa, Middle East, and South America. In recent years, a renewed interest in bean research in Western European countries and the U.S. is evident. In this review, certain biochemical, technological, nutritional, and toxicological aspects are discussed and the limitations and problems associated with dry beans of Phaseolus as human food are addressed.

Dry beans of Phaseolus: a review. Part 3

Beans of Phaseolus are important food crops both economically and nutritionally, and are cultivated and consumed world wide. With ever rising costs of meats, fresh fruits, and vegetables, dry beans are expected to contribute more to the human nutrition in coming years. Traditionally, they have been referred to as "poor man's meat" and have contributed significantly to the diets of many people of several countries in Asia, Africa, the Middle East, and South America. In recent years, a renewed interest in bean research in Western European countries and the U.S. is evident. In this review, certain biochemical, technological, nutritional, and toxicological aspects are discussed and the limitations and problems associated with dry beans of Phaseolus as human food are addressed.