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It is interesting that several of the studies in this issue of the journal focus on heat- and drought-tolerant plants. Two of them are highlighted in these application briefs: sorghum and okra.

Sorghum is a member of the grasses and is raised for grain and fodder in warm climates. In Africa, sorghum is prepared into a porridge or made into a flatbread. In other countries it is boiled like rice or made into cous-cous. Both alcoholic and nonalcoholic beverages are made from sorghum. It can also be substituted for wheat flour to make baked goods.

Okra is a member of the same plant family as cotton and cacao, and its edible immature green seed pods are consumed in the cuisines of many countries, including India, Thailand, and the Philippines. With more than 5 million tons produced each year, it is cultivated in regions with warm climates around the world. Okra is consumed fresh, frozen or as a canned vegetable. It is also used to thicken soups and stews.

Why is this noteworthy? Although food scientists and technologists have always explored alternatives to our major commodities, with increasing threats to plant production such as soil erosion, climate change, and plant disease, the need for alternatives becomes greater. More heat- and drought -tolerant plants that can be grown in many regions gain importance.

In addition to the highlights on sorghum and okra, other studies in this issue review the use of oligosaccharides, shed more understanding on the process of staling in bread, teach a machine to recognize a good cheese pizza, and explore how to ensure food safety of peanuts.

Oligosaccharides on the Go

  1. Top of page
  2. Oligosaccharides on the Go
  3. Shedding Light on the Mystery of Bread Staling
  4. Okra Ice Cream?
  5. Capturing the Best Cheese Pizza Topping with Machine Vision
  6. Roasting Peanuts to Ensure Safety
  7. Seeking the “Typical” South American Red Wine
  8. Using Sorghum Flour to Make Pasta

Oligosaccharides are low molecular weight carbohydrates, which are resistant to human digestive enzymes, pass through the upper digestive system intact and get fermented in the lower colon, producing short-chain fatty acids (SCFAs), which, in turn, nourish the resident beneficial microbiota. Starting in the 1980s, functional oligosaccharides emerged as components of food and dietary supplements. Their resistance to digestion and fermentation by colonic microbes allowed them to be useful as dietary fibers, sweeteners, humectants, and prebiotics. The market for prebiotics is expected to reach $4.5 billion by 2018.

The functional oligosaccharides include lactulose, fructo-oligosaccharides, galactooligosaccharides, soybean oligosaccharides, lactosucrose, isomalto-oligosaccharides, glucooligosaccharides, xylo-oligosaccharides, gentio-oligosaccharides, arabinoxylan oligosaccharide, mannan oligosaccharides, and pectin-derived acidic oligosaccharides.

This article by of a group of researchers in India and the U.S. reviews recent key findings on the role of the functional oligosaccharides in gut health restoration and probiotics induction; immunomodulation; cancer prevention; antihypertensive effects; hepatic protection; allergic inflammation mitigation; and oxidative stress lowering and neuroprotection. R1491–R1498

Shedding Light on the Mystery of Bread Staling

  1. Top of page
  2. Oligosaccharides on the Go
  3. Shedding Light on the Mystery of Bread Staling
  4. Okra Ice Cream?
  5. Capturing the Best Cheese Pizza Topping with Machine Vision
  6. Roasting Peanuts to Ensure Safety
  7. Seeking the “Typical” South American Red Wine
  8. Using Sorghum Flour to Make Pasta

Staling in bread is still not completely understood. Retrogradation of wheat starch occurs when gelatinized amylose–amylose or amylose–amylopectin forms a less soluble, crystalline state over time. Some studies have indicated that gluten had no effect on retrogradation of wheat starch, but others found that the staling rate of bread was decreased by increasing the amount of gluten. It has been proposed that interactions could exist between starch and gluten through hydrogen bonding, preventing the staling of starch.

The aim of this study was to investigate the relation between wheat proteins and the retrogradation of wheat starch, and to offer a theoretical foundation for the further study of interactions of wheat protein and starch during retrogradation. The researchers found that different wheat flour proteins have different effects on retrogradation of wheat starch. Glutenins retard retrogradation of wheat starch, while albumins, globulins, and gliadins promote retrogradation. The researchers pointed out that glycosidic bonds formed between wheat starch and gliadins might greatly resist hydrolysis of wheat starch by amylase. Such retrograded wheat starch would possibly become a new kind of resistant starch. C1505–C1511

Okra Ice Cream?

  1. Top of page
  2. Oligosaccharides on the Go
  3. Shedding Light on the Mystery of Bread Staling
  4. Okra Ice Cream?
  5. Capturing the Best Cheese Pizza Topping with Machine Vision
  6. Roasting Peanuts to Ensure Safety
  7. Seeking the “Typical” South American Red Wine
  8. Using Sorghum Flour to Make Pasta

Adding okra to ice cream might seem like an odd thing to do. But, there are several reasons to explore the use of okra cell wall materials as food ingredients. Okra is a prolific and fast growing plant for warm climates. Popular in India, Malaysia, the Philippines, and Thailand, world production of okra pods is more than 5 million tons a year. Okra can be used as a fresh, frozen, or canned vegetable. It is also used to thicken soups and stews. The polysaccharide found in okra could be an alternative to hydrocolloid food ingredients and add value to the crop for okra farmers.

Stabilizers are used in ice cream to increase mix viscosity, promote smooth texture, and improve frozen stability. This study shows that okra cell wall material and okra polysaccharide could be used as ice cream stabilizer to retard ice recrystallization and melt down of ice cream. Okra cell wall material and okra polysaccharide at 0.15% did not affect sensory perception scores for ice cream flavor, texture, and overall acceptance. Both ingredients (at 0.15%) reduced ice crystal growth to 107% and 87%, respectively, as compared to 132% for the control (0.00%). The researchers suggest that okra cell wall material and polysaccharide have a potential use as a stabilizer to control ice cream quality and retard ice recrystallization. E1522–E1527

Capturing the Best Cheese Pizza Topping with Machine Vision

  1. Top of page
  2. Oligosaccharides on the Go
  3. Shedding Light on the Mystery of Bread Staling
  4. Okra Ice Cream?
  5. Capturing the Best Cheese Pizza Topping with Machine Vision
  6. Roasting Peanuts to Ensure Safety
  7. Seeking the “Typical” South American Red Wine
  8. Using Sorghum Flour to Make Pasta

Image analysis techniques based on machine vision have been used in a variety of food processing applications and offers rapid, objective, and consistent assessment. In pizza processing, various techniques have been used to evaluate the shape and size of the pizza base, the sauce spread, and the pizza toppings. However, the appearance of pizzas baked with cheese is commonly evaluated by sensory method and colorimeter, and only Mozzarella cheese (which browns and blisters) has been investigated using machine vision.

A group of researchers from New Zealand and the UK aimed to develop improved methods for quantifying and differentiating the appearances of different pizzas after baking (by quantifying browning and blistering behavior). To achieve this aim, cheeses including Mozzarella, Cheddar, Colby, Edam, Emmental, Gruyere, and Provolone were baked on pizzas and their images were captured using machine vision; and the color, color uniformity, and browning areas of cheeses were evaluated. Then, to further understand the pizza baking performance of cheeses, some cheese attributes such as moisture, free oil, and others were evaluated.

Although the majority of pizza cheese is Mozzarella, alternative cheeses were used to exacerbate differences in browning and blistering behavior to optimize the quantification tool. This study helped to identify and characterize the unique attributes of Mozzarella that make it an excellent cheese pizza topping. The study leads to the development of a more sophisticated evaluation technique of pizza baking. The researchers recommend that comparisons of this technique and the evaluation of experienced graders be studied in more detail. E1528–E1534

Roasting Peanuts to Ensure Safety

  1. Top of page
  2. Oligosaccharides on the Go
  3. Shedding Light on the Mystery of Bread Staling
  4. Okra Ice Cream?
  5. Capturing the Best Cheese Pizza Topping with Machine Vision
  6. Roasting Peanuts to Ensure Safety
  7. Seeking the “Typical” South American Red Wine
  8. Using Sorghum Flour to Make Pasta

Widespread outbreaks attributed to contaminated peanut products and other nuts have spurred investigation of the prevalence of Salmonella in raw nuts. However, little information exists on the prevalence or level of Salmonella commonly found on raw nut kernels.

The researchers in this study compared the ability of different roasting techniques: oven, microwaving, and oven/microwave combinations to inactivate a Salmonella surrogate. Roasted peanut color, odor activity values, descriptive sensory panel analysis, free fatty acid, and peroxide values were also determined. All the treatments resulted in a minimum of 3 log reduction of inoculated bacterial population. Measured quality attributes and descriptive sensory analysis were similar for roasting treatments as compared to a commercial product. Lipid oxidation was not significantly different between the roasting methods, displaying no evidence that roasting time or temperature affected lipid oxidation, when an ideal color was produced.

Based on the evaluated safety and quality parameters, microwave or microwave and oven combination roasting technologies may be used as alternative roasting methods to produce peanut butter potentially decreasing the production costs. However, the researchers add that these lethal treatments will do nothing to protect finished nut products from downstream and postprocess contamination events. Investigation of several recent outbreaks has suggested that sanitary inadequacies including facility defects and unsatisfactory segregation of raw and finished product have been responsible for causing illness. S1584–S1594

Seeking the “Typical” South American Red Wine

  1. Top of page
  2. Oligosaccharides on the Go
  3. Shedding Light on the Mystery of Bread Staling
  4. Okra Ice Cream?
  5. Capturing the Best Cheese Pizza Topping with Machine Vision
  6. Roasting Peanuts to Ensure Safety
  7. Seeking the “Typical” South American Red Wine
  8. Using Sorghum Flour to Make Pasta

“Typicality” is a concept used in the wine industry to describe when consumers choose a wine bottle based on its varietal and country of origin and they believe that there is a combination of sensory attributes that differentiates this varietal or region from the others. A wine is typical when some of its characteristics, which reflect both its origin and varietal purity, can be identified and make it recognizable as belonging to a distinctive type. In a classic scenario the concept applies to so-called Old World wines from Europe, where many better wines are composed of a mixture of grape varieties produced in a specific region. France, for example, has more than 300 such wines. So-called New World wines are still predominantly monovarietals, for example, Cabernet Sauvignon.

A group of researchers from Brazil hypothesized that young wines could be sensorially characterized by varietal and country of origin, but this classification could change according to the vintage. To test this hypothesis, 138 young monovarietal red wines from Vitis vinifera grapes produced in 2009 and 2010 vintages were submitted to a sensory evaluation by a panel of wine experts.

Their data showed that wine experts were able to identify wines according to their varietal, origin, and price range, suggesting that there is typicality in young South American red wines. In addition, no effect of the vintage was observed on the sensory characterization of the wines. This result could be associated with the new viticulture or oenological practices used by the winemakers to compensate for environmental variation. S1595–S1603

Using Sorghum Flour to Make Pasta

  1. Top of page
  2. Oligosaccharides on the Go
  3. Shedding Light on the Mystery of Bread Staling
  4. Okra Ice Cream?
  5. Capturing the Best Cheese Pizza Topping with Machine Vision
  6. Roasting Peanuts to Ensure Safety
  7. Seeking the “Typical” South American Red Wine
  8. Using Sorghum Flour to Make Pasta

Sorghum is a drought- and heat-tolerant grain crop grown in many arid regions of the world. Whole grain sorghum is a source of resistant starch and polyphenolic antioxidants and its addition into staple food like pasta may reduce the starch digestibility. However, incorporating non-durum wheat materials into pasta provides a challenge in terms of maintaining cooking quality and consumer acceptability. This study looked at replacing durum wheat semolina with either red sorghum flour or white sorghum flour at 20%, 30%, and 40% incorporation levels.

The researchers found that the rapidly digestible starch decreased in all the sorghum-containing pastas compared to the control pasta. Sorghum flour did not affect the quality attributes (water absorption, swelling index, dry matter, adhesiveness, cohesiveness, and springiness), except color and hardness which were negatively affected. Consumer sensory results indicated that pasta samples containing 20% and 30% sorghum flour had acceptable palatability based on meeting one or both of the preset acceptability criteria. The researchers concluded that the addition of sorghum flour to pasta at 30% is possible to reduce starch digestibility, without affecting the cooking quality and consumer acceptability. S1560–S1567