Lactic acid was discovered in 1780 by C.W. Scheele in sour milk, and in 1881 Fermi obtained lactic acid by fermentation, resulting in its industrial production. The yearly world lactic acid production is expected to reach 259,000 metric tons by the year 2012. The interest in lactic acid is related to many aspects, among which is its relatively high added-value. In addition, such a chemical is GRAS (Generally Recognized As Safe), being recognized as harmless by the United States Food and Drug Administration, has a market with great growth potential, can be alternatively produced by fermentation or chemical synthesis and can employ a large variety of different waste materials as substrates. Lactic acid has many applications. Its existence in the form of two stereoisomers does in fact make the application of one of them or of the racemic mixture of great concern in different fields. In particular, the food and pharmaceutical industries have a preference for the isomer l (+), the only one that can be metabolized by the human body; however, the chemical industry requires one of the pure isomers or a mixture of both, according to the application. This review describes biotechnological processes to obtain lactic acid from polymeric substrates such as starchy and lignocellulosic materials. Open challenges are related to the technological optimization of the fermentation process and product purification and recovery. In addition, the opportunities and difficulties associated with using raw materials for lactic acid production are discussed.

https://maaz.ihmc.us/rid=1N4KLGGDB-C7FZZY-93H/Castillo%20Martinez%20et%20al.%20-%202013%20-%20Lactic%20acid%20properties,%20applications%20and%20productio.pdf

Lactic acid properties, applications and production: a review.

In the past, the beneficial effects of fermented foods on health were unknown, and so people primarily used fermentation to preserve foods, enhance shelf life, and improve flavour Fermented foods became an important part of the diet in many cultures, and over time fermentation has been associated with many health benefits Because of this, the fermentation process and the resulting fermented products have recently attracted scientific interest In addition, microorganisms contributing to the fermentation process have recently been associated with many health benefits, and so these microorganisms have become another focus of attention Lactic acid bacteria (LAB) have been some of the most studied microorganisms During fermentation, these bacteria synthesize vitamins and minerals, produce biologically active peptides with enzymes such as proteinase and peptidase, and remove some non-nutrients Compounds known as biologically active peptides, which are produced by the bacteria responsible for fermentation, are also well known for their health benefits Among these peptides, conjugated linoleic acids (CLA) have a blood pressure lowering effect, exopolysaccharides exhibit prebiotic properties, bacteriocins show anti-microbial effects, sphingolipids have anti-carcinogenic and anti-microbial properties, and bioactive peptides exhibit anti-oxidant, anti-microbial, opioid antagonist, anti-allergenic, and blood pressure lowering effects As a result, fermented foods provide many health benefits such as anti-oxidant, anti-microbial, anti-fungal, anti-inflammatory, anti-diabetic and anti-atherosclerotic activity However, some studies have shown no relationship between fermented foods and health benefits Therefore, this paper aims to investigate the health effects of fermented foods

Health Benefits of Fermented Foods

Fermentation is an ancient form of food preservation, which also improves the nutritional content of foods In many regions of the world, fermented beverages have become known for their health-promoting attributes In addition to harnessing traditional beverages for commercial use, there have recently been innovative efforts to develop non-dairy probiotic fermented beverages from a variety of substrates, including soy milk, whey, cereals and vegetable and fruit juices On the basis of recent developments, it is anticipated that fermented beverages will continue to be a significant component within the functional food market

/pdf/fermented-beverages-with-health-promoting-potential-past-and-y336kayqtp.pdf

Fermented beverages with health-promoting potential: Past and future perspectives

Soluble dietary fibers (SDFs) are present in small quantities in almost each and every commodity and in combination with insoluble dietary fiber contribute towards total dietary fiber. The beneficial properties of SDFs have been associated with their significant role in human physiological function. Reductions in cholesterol level and blood pressure, prevention of gastrointestinal problems, protection against onset of several cancers, which include colorectal, prostate, and breast cancer, increased mineral bioavailability, and many more are the salient features of their potential. Some of the new unexplored soluble fibers are still under investigation for their use in a variety of commercial foodstuffs. This review outlines the various SDFs available, their major sources, and their potential functional role in human health.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1541-4337.2009.00099.x

Soluble Dietary Fiber

Lactobacillus plantarum (widespread member of the genus Lactobacillus) is one of the most studied species extensively used in food industry as probiotic microorganism and/or microbial starter. The exploitation of Lb. plantarum strains with their long history in food fermentation forms an emerging field and design of added-value foods. Lb. plantarum strains were also used to produce new functional (traditional/novel) foods and beverages with improved nutritional and technological features. Lb. plantarum strains were identified from many traditional foods and characterized for their systematics and molecular taxonomy, enzyme systems (α-amylase, esterase, lipase, α-glucosidase, β-glucosidase, enolase, phosphoketolase, lactase dehydrogenase, etc.), and bioactive compounds (bacteriocin, dipeptides, and other preservative compounds). This review emphasizes that the Lb. plantarum strains with their probiotic properties can have great effects against harmful microflora (foodborne pathogens) to increase safety and shelf-life of fermented foods.

/pdf/lactobacillus-plantarum-with-functional-properties-an-4l68m4m229.pdf

Lactobacillus plantarum with Functional Properties: An Approach to Increase Safety and Shelf-Life of Fermented Foods.

The use of starter cultures in the fermentation of boza, a traditional Turkish beverage

Determination of rheological properties of boza by using physical and sensory analysis

Tahin helva is one of Turkish traditional confectionary foods. Sesame paste, sugar syrup and soapwort extract were used for tahin helva’s production. The purpose of this study was to solve the oil separation problem occurred in tahin helva by using food additives permitted as an emulsifier for tahin helva in the Turkish and EU Codex. Sorbitan tristearate (STS), sorbitan monopalmitate (SMP) and their combinations (STS:SMP, 1:1) were added to tahin helva, then helva samples were stored at the storage temperatures of 20 °C, 30 °C, and 40 °C. The emulsifiers did not have any effect on physical, chemical and sensory properties of tahin helva except on its oil content, whereas storage temperature and storage time had effects on those properties of helva. STS:SMP combination was found to be statistically more effective than SMP and STS formulations in preventing oil separation. Penetration force of tahin helva has increased by increasing the storage temperature and storage time. It was found that there was a decrease in −a colour value of helva through the storage time at 20 °C and 30 °C, while there was an increase in that value at 40 °C. The highest change in the moisture content of all helva samples through storage was observed at the storage temperature of 20 °C. Sensory scores for appearance, texture and flavour characteristics of helva have decreased significantly during the storage period.

Effect of emulsifiers on oil separation problem and quality characteristics of Tahin Helva during storage

An improved method for the quantitative determination of carboxymethyl cellulose in food products

Subye, a traditional beverage of Turkey, is produced from melon seeds, sugar, and water. The standard production protocol for Subye beverage includes mixing minced rehydrated melon seed mass with sugar to obtain Subye paste in the ratio of 1:1.125 (w/w), respectively, and mixing 25% of the paste with water. The total moisture, sugar, fat, protein, and ash contents of the standardized beverage were found to be 84.24%, 11.65%, 1.52%, 1.35%, and 0.21%, respectively. A 99% suspension stability of the beverage was achieved after one day of storage by addition of a xanthan gum:guar gum combination (0.04%:0.5% and 0.05%:0.4%). No significant differences (p>0.05) were found between the gum-containing samples and control samples for the Hunter color values and for the sensory characteristics, such as mouthfeel, taste, and overall acceptability (except for appearance). Nisin:natamycin (2 ppb:30 ppm) was statistically found to be the most effective antimicrobial combination for aerobic mesophilic bacteria after storage for 6 days. Nisin:natamycin (2 ppb:30 ppm) and nisin:potassium sorbate (2 ppb:250 ppm) combinations were found the most effective antimicrobial combinations for mold and yeast count after storage for 3 days and 6 days, respectively.

/pdf/improvement-of-quality-and-shelf-life-of-subye-a-traditional-4amucy1yj1.pdf

Murat Zorba

Papers

The use of starter cultures in the fermentation of boza, a traditional Turkish beverage

Determination of rheological properties of boza by using physical and sensory analysis

Effect of emulsifiers on oil separation problem and quality characteristics of Tahin Helva during storage

An improved method for the quantitative determination of carboxymethyl cellulose in food products

Improvement of quality and shelf-life of Sübye, a traditional beverage of Turkey