Capsicum--production, technology, chemistry, and quality. Part III. Chemistry of the color, aroma, and pungency stimuli

The spice capsicum, the fruits of the genus Capsicum (Family Solanaceae), is a very popular food additive in many parts of the world, valued for the important sensory attributes of color, pungency, and aroma. A large number of varieties are widely cultivated and traded. The characteristic carotenoids of the bright red paprika and cayenne-type chillies, the high character impact aroma stimuli, the methoxy pyrazine of green bell capsicum, the esters of ripe tabasco and the highly potent pungency stimuli, and the capsaicinoids of African and other Asian varieties of chillies, have been of great interest to chemists and biochemists. Research workers in other disciplines such as genetics and breeding, agriculture, and technology have been interested in this spice to develop new varieties with combinations of different optimal levels of the stimuli for the sensory attributes and to maximize production of storable products for specific end uses. Physiologists have been intensely studying the action of the highly potent pungency stimuli and social psychologists the curious aspect of growing acceptance and preference for the initially unacceptable pungency sensation. In the sequential review of all these aspects of the fruit spice Capsicum, the earlier two parts covered history, botany, cultivation and primary processing, and processed products, standards, world production, and trade. In Part III, the chemistry, the compositional variations, synthesis and biosynthesis of the functional components, the carotenoids, the volatiles, and the capsaicinoids are comprehensively reviewed.     

Capsicum--production, technology, chemistry, and quality. Part IV. Evaluation of quality

Capsicum fruits are popular worldwide and are used in the cuisines of both the developing and the developed countries. With its different varieties, forms, and uses, the spice capsicum contributes to the entire gamut of sensory experience--color as finely ground paprika powder or extract in sausages, goulash, cheese, and snacks; both pungency and color as the many varieties of chillies used in Mexican, African, Indian, and southeast Asian cuisines; color, aroma, and mild pungency as the fresh green chillies used in many of the growing countries; and appearance, color, aroma, and texture as fresh fruit in salads and as a pickled and canned product. In three earlier parts in this series, the varieties, cultivation, and primary processing; the processed products, world production, and trade; and the chemistry of the color, aroma, and pungency stimuli have been reviewed. In this part, the evaluation of quality through instrumental determination of the causal components and the sensory evaluation of color, aroma, and pungency are discussed. Several methods for quantitative determination of the stimuli and the sensory evaluation of the responses to the stimuli are reviewed. The problems of sensory evaluation of color, aroma, and pungency, the dominant attributes for validation of the instrumentally determined values for carotenoids, volatiles, or particular fractions, and total and individual capsaicinoids are specifically discussed. Summarized details of selected instrumental methods for evaluating the stimuli, which are either validated by correlation to sensorily perceived responses or to adopted standards, are given along with representative data obtained for discussing the adequacy and reliability of the methods. Pungency as a specific gustatory perception and the many methods proposed to evaluate this quality are discussed. A recommended objective procedure for obtaining reproducible values is discussed, and a method for relating different panel results is shown. With such a method, highly significant correlations have been shown between estimated total capsaicinoids and the determined pungency. The estimation of total capsaicinoids by any simple, reliable method is shown to be adequate for quality control of pungency of Capsicum fruits.     

Citrus fruits--varieties, chemistry, technology, and quality evaluation. Part II. Chemistry, technology, and quality evaluation. A. Chemistry

In Part 2 of this review on citrus fruits, the literature on chemistry, technology, and quality evaluation are critically considered. Sweet oranges, mandarin, grapefruit, lemon, and lime are generally used for processing. The literature on chemical components of citrus fruit which include sugars, polysaccharides, oraganic acids, nitrogenous constituents and lipids; carotenoids which contribute to color; vitamins and minerals, and flavonoids; limonoids, some of which impart bitterness to the juice; and the volatile components which contribute to aroma have been reviewed. Chilled and pasteurized juices, juice concentrates, and beverages are the important products manufactured commercially, and to a limited extent powdered citrus juices, canned segments, and marmalades. The literature on the manufacture of these products also as new types of juice and oil extractors; TASTE and other types of evaporators; tank farms to store juice and concentrate in bulk; aseptic filling in bulk containers and retail packs; alternate flexible and rigid containers other than glass and tin; and recovery of volatile flavoring constituents during juice processing are some of the important technological developments in the recent past and have been discussed. Bitterness in citrus juices and its control, composition of cloud, and its stability and changes during storage have been reviewed. Essential oils, pectin, frozen and dried juice sacs, dried pulp and molasses, flavonoids, seed oil, and meal are the important byproducts, the manufacture of which is given in essential details. Generally, consumers judge the product on the basis of its sensory attributes. The quality of finished product is dependent upon the raw materials used and control of processes. The U.S. Department of Agriculture (USDA) standards for different products, physicochemical and microbiological parameters prescribed as indices of quality of fruit, juice, concentrate, and other products; composition of essential oils; and aroma concentrates are discussed in relation to sensory quality. Analytical methods for compounds affecting quality, and methods for detection of adulteration in different citrus products are briefly reviewed. The importance of sensorily evaluating quality of citrus products to select and develop quality control indices is emphasized. Areas where further research are required are indicated. A comprehensive bibliography is provided to aid further study and research.     

Capsicum--production, technology, chemistry, and quality--Part II. Processed products, standards, world production and trade

Capsicums, as a spice, have been known since the beginning of civilization and historically associated with the discovery of the New World. The genus Capsicum (Fam. Solanaceae) provides many varieties and adds color, pungency, and aroma to the cuisines of most of the world. From the pungent chilli, of interest also to pharmaceuticals, to the colorful paprika and the bell capsicums with its remarkable aroma, the genus has been of great interest for its chemistry and physiological action. Pungency as a sensory attribute, its evaluation, structure-activity relationship, and its increasing acceptance and preference by diverse populations of the world are of great interest to many research disciplines. In a comprehensive review of all aspects in four sequential parts, Part I deals with History, Botany, Cultivation, and Primary Processing (CRC Critical Review, Food Science and Nutrition). The Capsicums among the spices are second only to black pepper in trades both in volume and value. The production of the different forms of this spice as ground, specialty seasonings, and as the concentrated oleoresins through technologically advanced processes, proposed newer products, the standard to control quality of the different products, world production, trade, and prospects are reviewed in detail in this, Part II.     

Ginger — chemistry,technology, and quality evaluation: Part 2

Ginger is used in more ways than any other spice. This monograph, published in two parts, comprehensively reviews production, trade, processing, chemistry, and evaluation of quality. Botany, world varieties, agronomy, crop improvement, and potential are reviewed briefly with emphasis on the yield of functional components. Processing for the market, international trade patterns and factors influencing them are discussed. Derived products such as ginger powder, syruped ginger, volatile oil, and oleoresin are discussed in greater detail. The increasing world demand for quality products of added value such as the oleoresin and volatile oil show the prospects for their production in the growing countries. The chemistry of the components which contribute aroma and pungency that characterize ginger is critically reviewed. The second part deals with evaluation of quality. The physicochemical parameters prescribed as a measure of quality for ginger and its products in the existing standards, can assure only hygienic quality and purity, and possibly the source, when new parameters such as GC‐finger prints are included. The importance of sensorily evaluating flavor quality is emphasized to understand the variation in flavor quality required by the industrial and retail markets. Related areas, such as problems in sensory evaluation of intense flavored substances, objective flavor profile analysis, correlation of instrumental and sensory data are discussed, and our recent work in this area is summarized. Areas where more research is needed are indicated. Other areas briefly discussed are functional, physiological, and toxicological properties in use of ginger; biosynthetic aspects of the components stimulating flavor, structure and pungency and chemistry of spices from allied species and genera. A comprehensive bibliography is provided to aid in further study and research.     

Capsicum production, technology, chemistry, and quality. Part 1: History, botany, cultivation, and primary processing

The genus Capsicum (Fam. Solanaceae) was known to ancient cultures and was more recently historically associated with the discovery of the New World. This genus provides many species and varieties used in flavoring foods popular in the cuisines of many parts of the world. From the pungent chilli to the colorful paprika and the bell pepper, with its remarkable aroma, the genus is of great interest for its chemistry, sensory attributes, and physiological action. The Capsicums, among the spices, are second only to black pepper in trade both in volume and value. The production of the different pungency forms, the processed seasonings, and the concentrated oleoresins, through technologically advanced processes and in specified standard grades, are critically reviewed. The pungency of Capsicum fruits, its evaluation, chemical structure relationship, its increasing acceptance and preference by a variety of populations are of great research interest. The wide traditional use in the growing regions and its intense physiological effects have attracted the attention of researchers of many different disciplines. These aspects are reviewed in four sequential parts. Part I deals with history, botany, cultivation, and primary processing.     

Citrus fruits — varieties,chemistry, technology,and quality evaluation. Part I: Varieties,production, handling,and storage

In part I of this comprehensive critical review on citrus fruits, the origin, botany, and classification are briefly discussed. The present status of citrus breeding with the objectives of overcoming the serious problems of die‐back and other disastrous diseases, and of producing varieties having a long harvesting period and giving a higher yield of high quality fruits, have been critically reviewed. Factors affecting the fruit quality such as rootstock, climate, and nutrition are reviewed generally with reference to established types of citrus fruits. World citrus production data has been carefully collected and presented both country‐wise and fruit‐wise to show the enormous growth and potential. Changes in composition during growth and maturation are presented with the view to fixing maturity and quality parameters and standards. Harvesting, handling, transportation, and storage aspects have been reviewed from the standpoint of optimal maintenance of quality of fruits intended for processing as well as for sale as fresh table fruit. The current problems that demand early solution have been highlighted. The succeeding parts will review chemistry, processing, and evaluation of quality.     

Citrus fruits. Part II. Chemistry,technology, and quality evaluation. C. quality evaluation

In Part II of this review on citrus fruits, the literature on chemistry, technology, and quality evaluation are critically considered. Sweet oranges, mandarin, grapefruit, lemon and lime are generally used for processing. The literature on chemical components of citrus fruits reviewed and discussed in Section A includes the following: sugars, polysaccharides, organic acids, nitrogenous constituents, and lipids; carotenoids which contribute to color; vitamins and minerals, and flavonoids; limonoids, some of which impart bitterness to the juice, and the volatile components which contribute to aroma. Chilled and pasteurized juices, juice concentrates, and beverages are the important products manufactured commercially, and to a limited extent powdered citrus juices, canned segments, and marmalades. The literature on the manufacture of these products as well as new types of juice and oil extractors, TASTE, and other types of evaporators, tank farms to store juice and concentrate in bulk, aseptic filling in bulk containers and retail packs, alternate flexible and rigid containers other than glass and tin and recovery of volatile flavoring constituents during juice processing are some of the important technological developments in the recent past which were discussed in Section B. Bitterness in citrus juices and its control, composition of cloud and its stability, and changes during storage have been reviewed. Essential oils, pectin, frozen and dried juice sacs, dried pulp and molasses, flavonoids, seed oil, and meal are the important by‐products, the manufacture of which is given in essential details. Generally, consumers judge the product on the basis of its sensory attributes. The quality of the finished products is dependent upon the raw materials used and control of processes. In this section, the USDA standards for different products, physico‐chemical and microbiological parameters prescribed as indices of quality of fruit, juice, concentrate, and other products, composition of essential oils, and aroma concentrates are discussed in relation to sensory quality. Analytical methods for compounds affecting quality and methods for detection of adulteration in different citrus products are briefly reviewed. The importance of sensorily evaluating quality of citrus products to select and develop quality control indices is emphasized. Areas where further research is required are indicated. A comprehensive bibliography is provided to aid further study and research.     

Citrus fruits. Part II. Chemistry, technology, and quality evaluation. B. Technology

In Part II of this review on citrus fruits, the literature on chemistry, technology, and quality evaluation are critically considered. Sweet oranges, mandarin, grapefruit, lemon, and lime are generally used for processing. The literature on chemical components of citrus fruit which include sugars, polysaccharides, organic acids, nitrogenous constituents and lipids; carotenoids which contribute to color; vitamins and minerals and flavonoids; limonoids, some of which impart bitterness to the juice; and the volatile components which contribute to aroma were reviewed in section A. Chilled and pasteurized juices, juice concentrates, and beverages are the important products manufactured commercially, and to a limited extent powdered citrus juices, canned segments, and marmalades. The literature on the manufacture of these products also as new types of juice and oil extractors; TASTE and other types of evaporators; tank farms to store juice and concentrate in bulk; aseptic filling in bulk containers and retail packs; alternate flexible and rigid containers other than glass and tin; and recovery of volatile flavoring constituents during juice processing are some of the important technological developments in the recent past and have been discussed in this section. Bitterness in citrus juices and its control, composition of cloud, and its stability and changes during storage have been reviewed. Essential oils, pectin, frozen and dried juice sacs, dried pulp and molasses, flavonoids, seed oil, and meal are the important byproducts, the manufacture of which is given in essential details. Generally, consumers judge the product on the basis of its sensory attributes. The quality of finished product is dependent upon the raw materials used and control of processes. In section C, the U.S. Department of Agriculture (USDA) standards for different products, physicochemical and microbiological parameters prescribed as indices of quality of fruit, juice, concentrate, and other products; composition of essential oils; and aroma concentrates are discussed in relation to sensory quality. Analytical methods for compounds affecting quality, and methods for detection of adulteration in different citrus products are briefly reviewed. The importance of sensorily evaluating quality of citrus products to select and develop quality control indices is emphasized. Areas where further research are required are indicated. A comprehensive bibliography is provided to aid further study and research.     

Blanching effects on chemistry, quality and structure of green beans (cv. Moncayo)

Green beans (cv. Moncayo) were blanched at 65, 70, 75, 80, 85, 90 and 97 °C for 2.5, 5, 10, 20 and 40 min. Pectinesterase (PE) activity was highest in cell-wall-bound extracts of beans blanched at 70 °C/10 min. The lowest water-soluble pectin fraction, the highest EDTA-soluble pectin fraction and the lowest degree of esterification of the EDTA-soluble fraction were all recorded for the same temperature/time combination; these effects can therefore be attributed to PE activity. Chemical changes did not affect initial firmness of the beans, which was practically constant after blanching at 65, 70, 75 and 80 °C. Simple first-order models were adequate to establish softening kinetics for beans blanched at 85, 90 and 97 °C. In this temperature range, Kramer maximum force was the mechanical parameter that best characterised bean softening by blanching. For all temperatures, short-time blanching increased the coloration and total chlorophyll content of the samples with respect to fresh control, thus precluding the use of simple models. In the treated beans, the ascorbic acid content was consistently lower than in the control and decreased continuously with increasing time. Microphotographs showed no appreciable differences in morphology between fresh and blanched beans at 65, 70 and 75 °C, which would explain the similarity of mechanical behaviour in these samples. Blanching at 85, 90 and 97 °C caused loosening and swelling of the cell walls owing to breakdown of the pectic material, which again helps to explain the observed loss of firmness.     

Effects of halothane genotype and pre-slaughter treatment on pig meat quality. Part 1. Post mortem metabolism, meat quality indicators and sensory traits of m. Longissimus lumborum

Forty-eight castrated F₂ offspring of Piétrain and Large White pigs were allocated to a 3 × 2 factorial design in order to study the interactive effect of halothane genotype (NN, Nn and nn) and pre-slaughter treatment [referred to as ‘Experimental’ (EXP) and ‘Commercial-like’ (COL) conditions; the latter combining short transportation, mixing unfamiliar pigs and slaughtering shortly after transport] on muscle post mortem changes and meat quality. The pigs were slaughtered over 4 days. Pre-slaughter glycogen depletion in M. longissimus lumborum (LL) was greater in the nn pigs, compared with the two other genotypes. Lactate accumulation post mortem in LL muscle was greater and the pH value at 40 min post mortem was lower in nn compared with NN pigs. Nn pigs were close to nn pigs for lactate accumulation and showed intermediate pH values in the LL muscle. In the M. semimembranosus (SM), NN and Nn pigs showed the same rate of post mortem changes, as evidenced by similar glycogen, lactate, creatine phosphate and ATP levels, and pH values at 40 min post mortem. Pre-slaughter treatment did not affect the rate of post mortem changes in both muscles and no interactive effect with halothane genotype was found. The pigs slaughtered under the ‘COL’ conditions had a significantly higher ultimate pH in the LL and SM muscles than those slaughtered under the ‘EXP’ conditions. The LL muscle from nn pigs was paler (higher L*) than that of NN and Nn pigs. In SM muscle, Nn pigs showed a significantly higher L* value than NN pigs. Drip loss of the LL muscle was significantly higher in nn compared with NN pigs, the heterozygous pigs being intermediate. Sensory evaluation of the LL muscle showed that nn pigs had a lower colour intensity and colour homogeneity of raw meat than NN and Nn pigs. Tenderness was significantly lower in nn compared with NN pigs, the Nn pigs being intermediate. Pre-slaughter treatment significantly increased ultimate pH in both muscles (LL and SM) but did not affect significantly the rate of pH fall (pH₄₀). It did not affect any of the meat quality traits and no interactive effect with halothane genotype was found. These results confirmed the influence of the halothane gene on the kinetics of muscle post mortem changes and related meat quality traits. They also confirmed the intermediate position of heterozygous pigs in terms of meat quality.     

Studies on the composition,quality and processing of triticale Part I. Physico-chemical characteristics

Studies on the physicochemical characteristics of 14 promising strains of triticale and two check wheat varieties (Kalyansona and WL 711) grown under similar agronomic conditions were conducted. Significant differences were obtained for 1000 kernel weight ranging from 34.9 to 51.8 g, hectolitre weight ranging from 64.7 to 73.5 kg and pearling index depicting grain hardness varying significantly from 22.3 to 39.9 %. Higher contents of protein (13.1 %), ash (1.83 %), lipids (2.65%), crude fibre (2.37%), energy value (1486 KJ/100 g), diastatic activity (283 mg maltose/iog flour), reducing sugars (65.6 mg maltose/10 g) and non-reducing sugars (244 mg maltose/10 g) were observed in triticale than those in wheat. Low values of PELSHENKE and sedimentation tests indicated poor gluten quality in triticale.     

Comparing equivalent thermal, high pressure and pulsed electric field processes for mild pasteurization of orange juice. Part I: Impact on overall quality attributes

Mild heat pasteurization, high pressure processing (HP) and pulsed electric field (PEF) processing of freshly squeezed orange juice were comparatively evaluated examining their impact on microbial load and quality parameters immediately after processing and during two months of storage. Microbial counts for treated juices were reduced beyond detectable levels immediately after processing and up to 2 months of refrigerated storage. Quality parameters such as pH, dry matter content and brix were not significantly different when comparing juices immediately after treatment and were, for all treatments, constant during storage time. Quality parameters related to pectinmethylesterase (PME) inactivation, like cloud stability and viscosity, were dependent on the specific treatments that were applied. Mild heat pasteurization was found to result in the most stable orange juice. Results for HP are nearly comparable to PEF except on cloud degradation, where a lower degradation rate was found for HP. For PEF, residual enzyme activity was clearly responsible for changes in viscosity and cloud stability during storage.

Industrial relevance

Development of mild processing technologies with a minimal impact on fruit juice can be considered as a true alternative of fresh fruit. The present work presents a fair comparison of mild heat treated, high pressure (HP) and pulsed electric field (PEF) processed orange juice as an alternative for thermal pasteurization. Orange juices were monitored during two months of storage.     

The application of multivariat mathematical-statistical methods to the solution of problems in nutrition theory,nutritional economics and food technology Part 4. Optimization with n ≥ 2 effect variables

The milling industry faces the task of saving energy without impairing the quantity and quality of the products. By applying experimental plans for the optimization of several effect variables, approximations (compromise solutions) between the cause variables (conditioning parameters) and the effect variables (quantity and quality parameters) are sought, which satisfy the aims laid down.     

Studies on the composition,quality and processing of triticale Part 3. Rheological and baking properties

Studies on rheological and baking properties of 14 promising strains of triticale and two check wheat varieties from India are reported. The farinograms obtained from triticale flours, in general, revealed poor dough development time and lower stability than those from wheat flours. The mean water absorption capacity of triticale flours was 54.3 percent compared to 64.4 percent of wheat flour. The triticale flour produced poor loaf volumes with mean value of 399 cm³ compared to 475 cm³ of wheat flour. Cookie baking tests showed that triticale flours were eminently suited for this purpose because of their soft flour and weaker gluten. Triticale whole meal required much less water for preparation of dough for chapatis and produced red coloured chapatis which tended to stale faster.     

The application of multivariat mathematical-statistical methods to the solution of problems in nutrition science,food economics and foodstuff technology Part 3. Statistical second order designs

The application of second order designs is dealt with in the case of the optimization of waffle production. A second order design with 3 explanatory variables (protease supply, reaction time, water addition) is worked out. The results are evaluated under four aspects:

• – the computation of statistical data
• – the crest-line analysis according to Hoerl (optimization)
• – the graphical presentation of results and
• – the computation of further combinations.

Control experiments using the second order designs give 3% deviation, compared to 17% using the first order design. Hence it follows that the second order design describes the relationship between effect variable and explanatory variable exactly.     

Studies on the composition,quality and processing of triticale. Part II. Mineral composition of grain and flour

Mineral composition of grain and flour in 14 promising triticale strains from India are reported. The mean values for whole grain, i.e. Ca (0.47 mg/g), P (2.70 mg/g), K 4.60 mg/g, Na (352 μg/g), Zn (41.6 μg/g), Cu (7.0 μg/g), Fe (73.4 μg/g) and Mn (33.6 μg/g) were obtained as compared to those of flour, i.e. Ca (0.27 mg/g), P (0.97 mg/g), K (1.64 mg/g), Na (231 μg/g), Zn (26 μg/g), Cu (4.0 μg/g), Fe (42 μg/g) and Mn (10.5 μg/g), respectively. These values were found to be considerably higher than those of wheat. Highly significant positive correlations of ash with sodium and zinc in whole grain were observed. In the case of triticale flour, highly significant positive correlations of ash with manganese, phosphorus and potassium were obtained.