Showing papers in "Food Reviews International in 2001"

Transglutaminase: its utilization in the food industry

Abstract: Transglutaminase is an enzyme that forms crosslinks between protein molecules. This crosslinkage has unique effects on protein properties, gelation capability, thermal stability, water-holding capacity, etc. A transglutaminase has been isolated from Streptoverticillium sp., and its practical use in the food industry realized. Transglutaminase is now widely used in seafood, surimi products, meat products, noodles/pasta, dairy products, baked goods, and so on. It has great potential to improve the firmness, elasticity, viscosity, heat stability, and water-holding capacity of prepared foods through the mild enzyme reaction. The overall applications of transglutaminase in the food industry are reviewed.

Determination of stable isotope ratios in food analysis.

Abstract: Within the last few years, stable isotope analysis has gained increasing importance in authenticity control of food and food ingredients. The development of the methodology from its start in the geological sciences is reviewed, the requirements and the specific features of the technique in the area of food quality assessment are outlined, and the progress in instrumentation during the last few decades is described. Scope and limits of the analysis of stable isotope ratios to assess the quality and to determine the origin are demonstrated for foods, such as fruit juice, wine, spirits, or beer. The classical approaches investigating hydrogen, carbon and oxygen isotopes as well as strategies including elements, such as nitrogen and sulfur, are reviewed. The present state of the art and future possibilities of the methodology are discussed.

Analytical chemistry: unlocking the secrets of wine flavor

Abstract: Knowledge of wine flavor has paralleled developments in analytical chemistry. In the 19th century, analytical methods focused on the determination of major wine components such as ethanol, organic acids, and sugars. The development of chromatographic techniques in the early 1900s and particularly development of gas chromatography in the early 1950s ushered in a new era of discovery for analytical chemists. Currently, more than 1300 volatile compounds have been identified in alcoholic beverages and new compounds continue to be discovered. At the beginning of the 21st century, the focus is beginning to shift away from identification and quantification of new flavor compounds and toward developing dynamic analytical techniques that can model the complex relationships between volatile composition and sensory properties. In addition, rapid, readily automated techniques that can be used to optimize agricultural (viticultural) practices and processing or aging conditions are being evaluated and developed. Primar...

Fish sauce products and manufacturing: a review

Abstract: Fish sauce, due to its characteristic flavor and taste, is a popular condiment for cooking and dipping. Biochemically, fish sauce is salt-soluble protein in the form of amino acids and peptides. It is developed microbiologically with halophilic bacteria, which are principally responsible for flavor and aroma. This review article covers the manufacturing methods of fish sauce, factors affecting the quality of fish sauce, nutritional values of fish sauce, microorganisms involved with fermentation, and flavor. In addition, rapid fermentation to reduce time and new parameters to estimate the quality of fish sauce are reviewed. Along with a new approach for estimating the quality of fish sauce, the quantitative analysis of degradation compounds from ATP and other specific protein compounds in fish sauce are discussed.

Vanilla production: technological, chemical, and biosynthetic aspects

Abstract: This review covers the most recent literature on vanilla research. Besides the curing process, chemistry in green and cured beans, as well as studies on the biosynthetic pathways of the most important aroma compounds are discussed. Despite intensive research on the curing process, the traditional curing procedures are still widely used. The role of enzymes involved in the curing process is not fully understood. The biosynthesis of vanilla aroma compounds is still under investigation. Data obtained from plant cell cultures are not always in accordance with those from the plant. The glycosylation of the compounds in vivo is still a point of study. Alternative routes to vanillin involving microbial biotransformations are outlined.

Diterpenes and diterpene esters in coffee

Abstract: Coffee oil contains pentacyclic diterpenes as typical lipid constituents which have not been detected in any other foods. Major representatives are 16-O-methylcafestol, cafestol, and kahweol. Cafestol is contained in Arabica as well as in Robusta coffee. 16-O-Methylcafestol is found only in Robusta coffee. Larger quantities of kahweol were detected in Arabica coffee, but only trace amounts are present in Robusta. In coffee oil, the diterpenes are hardly present in free form. They are largely esterified with fatty acids. Up to 14 fatty acid esters of 16-O-methylcafestol and cafestol have been identified. Palmitate followed by linoleate, oleate, stearate, arachidate, and behenate comprise almost 98% of the acid moieties. In Robusta coffee, the total amount of these six 16-O-methylcafestol esters are between 1.0 and 3.0 g/kg d.m. The contents of the corresponding cafestol esters vary between 2.0 and 8.0 g/kg d.m. in Robusta coffee and 9.0 and 22.0 g/kg d.m. in Arabica coffee. Roasting has little influence on...

Authenticity assessment of fats and oils

Abstract: Authenticity is an important issue for the food industry due to legal compliance, economic reasons (right goods for the right price), guarantee of a constant well-defined quality, use of safe ingredients (no hazardous substitutes), and religious reasons (halal, kosher). This report gives an extensive overview on the authenticity assessment of oils and fats for food products and summarizes the principal techniques useful for this assessment. Scope and limits of different analytical tools are discussed.

Antimicrobial activities of sulfur compounds derived from s-alk (en) yl-l-cysteine sulfoxides in allium and brassica

Abstract: Allium and Brassica vegetables have long been known for their antimicrobial activity against various microorganisms, including Gram-positive and Gram-negative bacteria and fungi. Most microorganisms tested were sensitive to extracts of the Allium and Brassica vegetables and the degree of sensitivity varied depending on the strain under study and test conditions. Among the vegetables, garlic showed the most potent activity, followed by onion. Brassica, including cabbage, showed the least potent activity. The principal antimicrobial compounds of Allium and Brassica have been elucidated as allicin (S-allyl-L-propenethiosulfinate) and methyl methanethiosulfinate, respectively. Both compounds belong to the same chemical group, thiosulfinate, generated from S-allyl and S-methyl derivatives of L-cysteine sulfoxide, respectively, existing in Allium and Brassica as major non-protein sulfur-containing amino acids. There have been only few applications of garlic as a natural food preservative, in spite of numerous s...

Recycling of polymeric materials used for food packaging: current status and perspectives

Abstract: Packaging materials are currently considered an important source of environmental waste because of their great volume. Although for materials like glass, aluminum, and paperboard recycling has been rather extensively practiced, it proved to be a much more arduous task for polymeric materials because of their great variety and the coexistence/mixing of various polymers either as blends or as copolymers. Therefore, constructive approach to recycling would consist of reviewing its current status worldwide to make a comprehensive presentation of the current trends and the state of art techniques for plastic disposal, sorting, and recycling. Although mechanical, feedstock, and chemical recycling of polymers are thoroughly analyzed within the frame of this review, other alternatives such as landfill, incineration, pyrolysis, reuse and recovery, and composting are also presented and commented.

Enantioselective fate of chiral chlorinated hydrocarbons and their metabolites in environmental samples

Abstract: Gas chromatographic enantioseparation of chiral organochlorines (α-HCH, cis- and trans-chlordane, heptachlor, heptachlor epoxide, oxychlordane, o,p′-DDT, compounds of technical toxaphene, stable atropisomeric PCBs and methylsulfonyl-PCBs) has been achieved during the last decade. For this purpose chiral stationary phases based on cyclodextrin derivatives have been applied in combination with GC/ECD, GC/MS, MDGC, and MS/MS. With these techniques methods have been developed which have been used to study the enantioselective fate of the chiral organochlorines. Changes in the enantioratios and conclusions drawn are reviewed.

Implementation of hazard analysis critical control point (haccp) system to the non-alcoholic beverage industry

Abstract: Non-alcoholic beverages, particularly, bottled water and fruit juices (carbonated and non-carbonated) are the most widespread food industries worldwide. The industry objective is to process at the lowest possible cost while maintaining the organoleptic stability and quality of the final product. The latter can be achieved through strict adherence to quality (ISO 9001/2) and safety (HACCP) management systems. The flow diagrams for the production of bottled water, several juices (orange, lemon, apple), carbonated drinks, coffee and tea are shown accompanied with a synoptical implementation of the HACCP system (critical control points, critical limits, preventive and corrective actions).

Technology choice and technical capacity in gari production

Abstract: This study was undertaken to assess the capacity and technology needs of women in Osun and Ondo States for gari production. The field survey was carried out by means of a structured questionnaire, administered through a participatory learning technique. At least two processing centers were visited in each Local Government Area in the two States. Altogether a total of 63 gari processing centers were visited. Mechanical grating of (manually) peeled cassava tubers has been fully adopted, while over 88% of processors have also embraced mechanical dewatering of the grated mash. Manual sieving is still predominant as mechanical sieving devices so far introduced still present problems; Frying also remains a manual operation, though some improved frying devices are being adopted. Women involvement in the operation and management of mechanical devices is not encouraging. Processing centers utilising diesel engine as prime movers predominate (84.7%), but they mostly employ male operators. This study however reveals...

The use of chemical markers and model studies to assess the in vitro pro- and antioxidative properties of methylxanthine-rich beverages

Abstract: Chemical markers and model studies are useful in predicting the stability and shelf life of foods and beverages in food technology and chemistry. Chemical modification induced by food processing has an impact on the reactivity and chemical properties of the food constituents, frequently giving rise to new molecules with enhanced antioxidative activity and potential health benefit. In the case of coffee, tea, and cocoa, these positive characteristics are often associated with dietary polyphenols. In particular, the often referred to “paradox” behavior of endogenous polyphenols to act as anti- and/or prooxidants is demonstrated with the aid of in vitro model studies. Furthermore, in-situ chemical markers such as 8-oxocaffeine are described in methylxanthine-rich beverages that reflect oxidative reactions. Such chemicals can be employed to help assess the impact of processing conditions on food quality as well as to predict the stability of the final product.